Articles | Volume 18, issue 10
https://doi.org/10.5194/cp-18-2345-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-18-2345-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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24 Oct 2022
Research article | Highlight paper |
| 24 Oct 2022
| 24 Oct 2022
Is it possible to estimate aerosol optical depth from historic colour paintings?
Christian von Savigny
CORRESPONDING AUTHOR
Institute of Physics, University of Greifswald, Felix-Hausdorff-Str. 6, 17489 Greifswald, Germany
Anna Lange
Institute of Physics, University of Greifswald, Felix-Hausdorff-Str. 6, 17489 Greifswald, Germany
Anne Hemkendreis
Institute of Art History, University of Freiburg, Platz der Universität 3, 79085 Freiburg, Germany
Christoph G. Hoffmann
Institute of Physics, University of Greifswald, Felix-Hausdorff-Str. 6, 17489 Greifswald, Germany
Alexei Rozanov
Institute of Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany
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Sandra Wallis, Matthew DeLand, and Christian von Savigny
EGUsphere, https://doi.org/10.5194/egusphere-2024-2165, https://doi.org/10.5194/egusphere-2024-2165, 2024
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The 2022 Hunga eruption emitted about 150 Tg H2O that partly reached the upper polar SH mesosphere in the beginning of 2024. Noctilucent clouds (NLC) did not show a clear perturbation in their occurrence frequency, but the slight increase from mid-January to February could potentially be caused by the additional H2O. It needs 2 years to reach the summer polar mesopause region, analogous to the 1883 Krakatau eruption that is argued to have caused the first sightings of NCLs.
Felix Wrana, Terry Deshler, Christian Löns, Larry W. Thomason, and Christian von Savigny
EGUsphere, https://doi.org/10.5194/egusphere-2024-2942, https://doi.org/10.5194/egusphere-2024-2942, 2024
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There is a natural and globally occurring layer of small droplets (aerosols) in roughly 20 km altitude in the atmosphere. In this work, the size of these aerosols is calculated from satellite measurements for the years 2002 to 2005, which is important for the aerosols cooling effect on Earth's climate. These years are interesting, because there were no large volcanic eruptions that would change the background state of the aerosols. The results are compared to reliable balloon-borne measurements.
Christine Pohl, Felix Wrana, Alexei Rozanov, Terry Deshler, Elizaveta Malinina, Christian von Savigny, Landon A. Rieger, Adam E. Bourassa, and John P. Burrows
Atmos. Meas. Tech., 17, 4153–4181, https://doi.org/10.5194/amt-17-4153-2024, https://doi.org/10.5194/amt-17-4153-2024, 2024
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Knowledge of stratospheric aerosol characteristics is important for understanding chemical and climate aerosol feedbacks. Two particle size distribution parameters, the aerosol extinction coefficient and the effective radius, are obtained from SCIAMACHY limb observations. The aerosol characteristics show good agreement with independent data sets from balloon-borne and satellite observations. This data set expands the limited knowledge of stratospheric aerosol characteristics.
Christian von Savigny, Anna Lange, Christoph G. Hoffmann, and Alexei Rozanov
Atmos. Chem. Phys., 24, 2415–2422, https://doi.org/10.5194/acp-24-2415-2024, https://doi.org/10.5194/acp-24-2415-2024, 2024
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It is well known that volcanic eruptions strongly affect the colours of the twilight sky. Typically, volcanic eruptions lead to enhanced reddish and violet twilight colours. In rare cases, however, volcanic eruptions can also lead to green sunsets. This study provides an explanation for the occurrence of these unusual green sunsets based on simulations with a radiative transfer model. Green volcanic sunsets require a sufficient stratospheric aerosol optical depth and specific aerosol sizes.
Anna Lange, Alexei Rozanov, and Christian von Savigny
Atmos. Chem. Phys., 23, 14829–14839, https://doi.org/10.5194/acp-23-14829-2023, https://doi.org/10.5194/acp-23-14829-2023, 2023
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We were able to demonstrate quantitatively that the blue colour of the sky cannot be solely attributed to Rayleigh scattering. The influence of ozone on the blue colour of the sky is calculated for different viewing geometries, total ozone columns and an enhanced stratospheric aerosol scenario. Furthermore, the effects of polarisation, surface albedo and observer height are investigated.
John M. C. Plane, Jörg Gumbel, Konstantinos S. Kalogerakis, Daniel R. Marsh, and Christian von Savigny
Atmos. Chem. Phys., 23, 13255–13282, https://doi.org/10.5194/acp-23-13255-2023, https://doi.org/10.5194/acp-23-13255-2023, 2023
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The mesosphere or lower thermosphere region of the atmosphere borders the edge of space. It is subject to extreme ultraviolet photons and charged particles from the Sun and atmospheric gravity waves from below, which tend to break in this region. The pressure is very low, which facilitates chemistry involving species in excited states, and this is also the region where cosmic dust ablates and injects various metals. The result is a unique and exotic chemistry.
Christoph G. Hoffmann, Lena G. Buth, and Christian von Savigny
Atmos. Chem. Phys., 23, 12781–12799, https://doi.org/10.5194/acp-23-12781-2023, https://doi.org/10.5194/acp-23-12781-2023, 2023
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The Madden–Julian oscillation is an important feature of weather in the tropics. Although it is mainly active in the troposphere, we show that it systematically influences the air temperature in the layers above, up to about 100 km altitude and from pole to pole. We have linked this to another known far-reaching process, interhemispheric coupling. This is basic research on atmospheric couplings and variability but might also be of interest for intraseasonal weather forecasting models.
Felix Wrana, Ulrike Niemeier, Larry W. Thomason, Sandra Wallis, and Christian von Savigny
Atmos. Chem. Phys., 23, 9725–9743, https://doi.org/10.5194/acp-23-9725-2023, https://doi.org/10.5194/acp-23-9725-2023, 2023
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The stratospheric aerosol layer is a naturally occurring and permanent layer of aerosol, in this case very small droplets of mostly sulfuric acid and water, that has a cooling effect on our climate. To quantify this effect and for our general understanding of stratospheric microphysical processes, knowledge of the size of those aerosol particles is needed. Using satellite measurements and atmospheric models we show that some volcanic eruptions can lead to on average smaller aerosol sizes.
Sandra Wallis, Hauke Schmidt, and Christian von Savigny
Atmos. Chem. Phys., 23, 7001–7014, https://doi.org/10.5194/acp-23-7001-2023, https://doi.org/10.5194/acp-23-7001-2023, 2023
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Strong volcanic eruptions are able to alter the temperature and the circulation of the middle atmosphere. This study simulates the atmospheric response to an idealized strong tropical eruption and focuses on the impact on the mesosphere. The simulations show a warming of the polar summer mesopause in the first November after the eruption. Our study indicates that this is mainly due to dynamical coupling in the summer hemisphere with a potential contribution from interhemispheric coupling.
Sandra Wallis, Christoph Gregor Hoffmann, and Christian von Savigny
Ann. Geophys., 40, 421–431, https://doi.org/10.5194/angeo-40-421-2022, https://doi.org/10.5194/angeo-40-421-2022, 2022
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Although the 1991 eruption of Mt Pinatubo had a severe impact on Earth's climate, the effect of this event on the mesosphere is not well understood. We investigated satellite-borne temperature measurements from the HALOE instrument and found indications that a positive temperature anomaly is present in the tropical upper mesosphere at the beginning of the HALOE time series, which may be related to the eruption of Mt. Pinatubo.
Anna Lange, Gerd Baumgarten, Alexei Rozanov, and Christian von Savigny
Ann. Geophys., 40, 407–419, https://doi.org/10.5194/angeo-40-407-2022, https://doi.org/10.5194/angeo-40-407-2022, 2022
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We investigate the influence of different parameters on the colour of noctilucent clouds (highest clouds in the atmosphere), using radiative transfer calculations. We determined the effect of the particle size, optical depth, single scattering/multiple scattering and ozone. For sufficiently large optical depth and for specific viewing geometries, ozone plays only a minor role in the blueish colour of noctilucent clouds (new result).
Mireia Papke Chica, Valerian Hahn, Tiziana Braeuer, Elena de la Torre Castro, Florian Ewald, Mathias Gergely, Simon Kirschler, Luca Bugliaro Goggia, Stefanie Knobloch, Martina Kraemer, Johannes Lucke, Johanna Mayer, Raphael Maerkl, Manuel Moser, Laura Tomsche, Tina Jurkat-Witschas, Martin Zoeger, Christian von Savigny, and Christiane Voigt
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-255, https://doi.org/10.5194/acp-2022-255, 2022
Preprint withdrawn
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The mixed-phase temperature regime in convective clouds challenges our understanding of microphysical and radiative cloud properties. We provide a rare and unique dataset of aircraft in situ measurements in a strong mid-latitude convective system. We find that mechanisms initiating ice nucleation and growth strongly depend on temperature, relative humidity, and vertical velocity and variate within the measured system, resulting in altitude dependent changes of the cloud liquid and ice fraction.
Julia Koch, Adam Bourassa, Nick Lloyd, Chris Roth, and Christian von Savigny
Atmos. Chem. Phys., 22, 3191–3202, https://doi.org/10.5194/acp-22-3191-2022, https://doi.org/10.5194/acp-22-3191-2022, 2022
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The mesopause, the region of the earth's atmosphere between 85 and 100 km, is hard to access by direct measurements. Therefore we look for parameters that can be measured using satellite or ground-based measurements. In this study we researched sodium airglow, a phenomenon that occurs when sodium atoms are excited by chemical reactions. We compared satellite measurements of the airglow and resulting sodium concentration profiles to gain a better understanding of the sodium in that region.
Elizaveta Malinina, Alexei Rozanov, Ulrike Niemeier, Sandra Wallis, Carlo Arosio, Felix Wrana, Claudia Timmreck, Christian von Savigny, and John P. Burrows
Atmos. Chem. Phys., 21, 14871–14891, https://doi.org/10.5194/acp-21-14871-2021, https://doi.org/10.5194/acp-21-14871-2021, 2021
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In the paper, changes in the stratospheric aerosol loading after the 2018 Ambae eruption were analyzed using OMPS-LP observations. The eruption was also simulated with the MAECHAM5-HAM global climate model. Generally, the model and observations agree very well. We attribute the good consistency of the results to a precisely determined altitude and mass of the volcanic injection, as well as nudging of the meteorological data. The radiative forcing from the eruption was estimated to be −0.13 W m−2.
Nellie Wullenweber, Anna Lange, Alexei Rozanov, and Christian von Savigny
Clim. Past, 17, 969–983, https://doi.org/10.5194/cp-17-969-2021, https://doi.org/10.5194/cp-17-969-2021, 2021
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This study investigates the physical processes leading to the rare phenomenon of the sun appearing blue or green. The phenomenon is caused by anomalous scattering by, e.g., volcanic or forest fire aerosols. Unlike most other studies, our study includes a full treatment of the effect of Rayleigh scattering on the colour of the sun. We investigate different factors and revisit a historic example, i.e. the Canadian forest fires in 1950, that led to blue sun events in different European countries.
Felix Wrana, Christian von Savigny, Jacob Zalach, and Larry W. Thomason
Atmos. Meas. Tech., 14, 2345–2357, https://doi.org/10.5194/amt-14-2345-2021, https://doi.org/10.5194/amt-14-2345-2021, 2021
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In this paper, we describe a new method for calculating the size of naturally occurring droplets (aerosols) made mostly of sulfuric acid and water that can be found roughly at 20 km altitude in the atmosphere. We use data from the instrument SAGE III/ISS that is mounted on the International Space Station. We show that our method works well, and that the size parameters we calculate are reasonable and can be a valuable addition for a better understanding of aerosols and their effect on climate.
Larry W. Thomason, Mahesh Kovilakam, Anja Schmidt, Christian von Savigny, Travis Knepp, and Landon Rieger
Atmos. Chem. Phys., 21, 1143–1158, https://doi.org/10.5194/acp-21-1143-2021, https://doi.org/10.5194/acp-21-1143-2021, 2021
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Measurements of the impact of volcanic eruptions on stratospheric aerosol loading by space-based instruments show show a fairly well-behaved relationship between the magnitude and the apparent changes to aerosol size over several orders of magnitude. This directly measured relationship provides a unique opportunity to verify the performance of interactive aerosol models used in climate models.
Lukas O. Muser, Gholam Ali Hoshyaripour, Julia Bruckert, Ákos Horváth, Elizaveta Malinina, Sandra Wallis, Fred J. Prata, Alexei Rozanov, Christian von Savigny, Heike Vogel, and Bernhard Vogel
Atmos. Chem. Phys., 20, 15015–15036, https://doi.org/10.5194/acp-20-15015-2020, https://doi.org/10.5194/acp-20-15015-2020, 2020
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Volcanic aerosols endanger aircraft and thus disrupt air travel globally. For aviation safety, it is vital to know the location and lifetime of such aerosols in the atmosphere. Here we show that the interaction of volcanic particles with each other eventually reduces their atmospheric lifetime. Moreover, we demonstrate that sunlight heats these particles, which lifts them several kilometers in the atmosphere. These findings support a more reliable forecast of volcanic aerosol dispersion.
Thomas von Clarmann, Douglas A. Degenstein, Nathaniel J. Livesey, Stefan Bender, Amy Braverman, André Butz, Steven Compernolle, Robert Damadeo, Seth Dueck, Patrick Eriksson, Bernd Funke, Margaret C. Johnson, Yasuko Kasai, Arno Keppens, Anne Kleinert, Natalya A. Kramarova, Alexandra Laeng, Bavo Langerock, Vivienne H. Payne, Alexei Rozanov, Tomohiro O. Sato, Matthias Schneider, Patrick Sheese, Viktoria Sofieva, Gabriele P. Stiller, Christian von Savigny, and Daniel Zawada
Atmos. Meas. Tech., 13, 4393–4436, https://doi.org/10.5194/amt-13-4393-2020, https://doi.org/10.5194/amt-13-4393-2020, 2020
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Remote sensing of atmospheric state variables typically relies on the inverse solution of the radiative transfer equation. An adequately characterized retrieval provides information on the uncertainties of the estimated state variables as well as on how any constraint or a priori assumption affects the estimate. This paper summarizes related techniques and provides recommendations for unified error reporting.
Christian von Savigny and Christoph G. Hoffmann
Atmos. Meas. Tech., 13, 1909–1920, https://doi.org/10.5194/amt-13-1909-2020, https://doi.org/10.5194/amt-13-1909-2020, 2020
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Stratospheric sulfate aerosols increase the Earth's planetary albedo and can lead to significant surface cooling, for example in the aftermath of volcanic eruptions. Their particle size distribution, important for physical and chemical effects of these aerosols, is still not fully understood. The present paper proposes an explanation for systematic differences in aerosol particle size retrieved from measurements made in different measurement geometries and reported in earlier studies.
Olexandr Lednyts'kyy and Christian von Savigny
Atmos. Chem. Phys., 20, 2221–2261, https://doi.org/10.5194/acp-20-2221-2020, https://doi.org/10.5194/acp-20-2221-2020, 2020
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Atomic oxygen is a chemically active trace gas and a critical component of the energy balance of the mesosphere and lower thermosphere (MLT). By sequentially applying continuity equations of low degree, a new model representing the airglow and photochemistry of oxygen in the MLT is implemented, enabling comparisons with airglow observations at each step. The most effective data sets required to derive the abundance of atomic oxygen are the O2 atmospheric band emission, temperature, N2 and O2.
Piao Rong, Christian von Savigny, Chunmin Zhang, Christoph G. Hoffmann, and Michael J. Schwartz
Atmos. Chem. Phys., 20, 1737–1755, https://doi.org/10.5194/acp-20-1737-2020, https://doi.org/10.5194/acp-20-1737-2020, 2020
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We study the presence and characteristics of 27 d solar signatures in middle atmospheric temperature observed by the microwave limb sounder on NASA's Aura spacecraft. This is a highly interesting and significant subject because the physical and chemical mechanisms leading to these 27 d solar-driven signatures are, in many cases, not well understood. The analysis shows that highly significant 27 d solar signatures in middle atmospheric temperature are present at many altitudes and latitudes.
Jacob Zalach, Christian von Savigny, Arvid Langenbach, Gerd Baumgarten, Franz-Josef Lübken, and Adam Bourassa
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-267, https://doi.org/10.5194/amt-2019-267, 2019
Revised manuscript not accepted
Arvid Langenbach, Gerd Baumgarten, Jens Fiedler, Franz-Josef Lübken, Christian von Savigny, and Jacob Zalach
Atmos. Meas. Tech., 12, 4065–4076, https://doi.org/10.5194/amt-12-4065-2019, https://doi.org/10.5194/amt-12-4065-2019, 2019
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Stratospheric aerosol backscatter ratios in the Arctic using Rayleigh, Mie and Raman backscattered signals were calculated. A backscatter ratio calculation during daytime was performed for the first time. Sharp aerosol layers thinner than 1 km over several days were observed. The seasonal cycle of stratospheric background aerosol in high latitudes including the summer months was calculated for the first time. Top altitude of the aerosol layer was found to reach up to 34 km, especially in summer.
Christoph G. Hoffmann and Christian von Savigny
Atmos. Chem. Phys., 19, 4235–4256, https://doi.org/10.5194/acp-19-4235-2019, https://doi.org/10.5194/acp-19-4235-2019, 2019
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We examine a possible statistical linkage between atmospheric variability in the tropical troposphere on the intraseasonal timescale, which is known as Madden–Julian oscillation, and known variability of the solar radiation with a period of 27 days. This helps to understand tropospheric variability in more detail, which is generally of interest, e.g., for weather forecasting. We find indications for such a linkage; however, more research has to be conducted for an unambiguous attribution.
Christian von Savigny, Dieter H. W. Peters, and Günter Entzian
Atmos. Chem. Phys., 19, 2079–2093, https://doi.org/10.5194/acp-19-2079-2019, https://doi.org/10.5194/acp-19-2079-2019, 2019
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This study investigates solar effects in radio reflection height observations in the ionospheric D region at an altitude of about 80 km at northern midlatitudes. The analyzed time series covers almost six solar cycles. Statistically significant solar 27-day and 11-year signatures are identified. However, the driving mechanisms are not fully understood. We also provide evidence for dynamical effects on the radio reflection heights with periods close to the solar rotational cycle.
Tilo Fytterer, Christian von Savigny, Martin Mlynczak, and Miriam Sinnhuber
Atmos. Chem. Phys., 19, 1835–1851, https://doi.org/10.5194/acp-19-1835-2019, https://doi.org/10.5194/acp-19-1835-2019, 2019
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A model was developed to derive night-time atomic oxygen (O(3P)) and atomic hydrogen (H) from satellite observations in the altitude region between 75 km and 100 km. Comparisons between the
best-fit modeland the measurements suggest that chemical reactions involving O2 and O(3P) might occur differently than is usually assumed in literature. This considerably affects the derived abundances of O(3P) and H, which in turn might influence air temperature and winds of the whole atmosphere.
Martin P. Langowski, Christian von Savigny, John P. Burrows, Didier Fussen, Erin C. M. Dawkins, Wuhu Feng, John M. C. Plane, and Daniel R. Marsh
Atmos. Meas. Tech., 10, 2989–3006, https://doi.org/10.5194/amt-10-2989-2017, https://doi.org/10.5194/amt-10-2989-2017, 2017
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Meteoric metals form metal layers in the upper atmosphere anandplay a role in the formation of middle-atmospheric clouds and aerosols. However, the total metal influx rate is not well known. Global Na datasets from measurements and a model are available, which had not been compared yet on a global scale until this paper. Overall the agreement is good, and many differences between measurements are also found in the model simulations. However, the modeled layer altitude is too low.
Kai-Uwe Eichmann, Luca Lelli, Christian von Savigny, Harjinder Sembhi, and John P. Burrows
Atmos. Meas. Tech., 9, 793–815, https://doi.org/10.5194/amt-9-793-2016, https://doi.org/10.5194/amt-9-793-2016, 2016
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Height-resolved limb radiance spectra of the satellite instrument SCIAMACHY are used to retrieve cloud top heights with a colour index method. Clouds are detectable from the lower to the uppermost troposphere. These cloud heights help to improve the trace gas retrieval for the upper troposphere and lower stratosphere. Comparisons with other data sets have shown good agreement. As clouds and aerosols are not distinguishable, lower stratospheric volcanic aerosol clouds are detected in some years.
M. P. Langowski, C. von Savigny, J. P. Burrows, V. V. Rozanov, T. Dunker, U.-P. Hoppe, M. Sinnhuber, and A. C. Aikin
Atmos. Meas. Tech., 9, 295–311, https://doi.org/10.5194/amt-9-295-2016, https://doi.org/10.5194/amt-9-295-2016, 2016
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An algorithm has been developed for the retrieval of sodium atom (Na) number density on a latitude and altitude grid from SCIAMACHY limb measurements of the Na resonance fluorescence (multiannual means 2008–2012). The Na layer peaks at 90 to 93 km altitude and has a FWHM of 5 to 15 km. A summer minimum in peak density and width is observed at high latitudes. At low latitudes, a semiannual oscillation is found. The results are compared with other measurements and models and agree well with these.
F. Ebojie, J. P. Burrows, C. Gebhardt, A. Ladstätter-Weißenmayer, C. von Savigny, A. Rozanov, M. Weber, and H. Bovensmann
Atmos. Chem. Phys., 16, 417–436, https://doi.org/10.5194/acp-16-417-2016, https://doi.org/10.5194/acp-16-417-2016, 2016
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The goal of this study is to determine the global and zonal changes in the tropospheric ozone data product derived from SCIAMACHY limb-nadir-matching (LNM) observations during the period 2003–2011.
Tropospheric O3 shows statistically significant increases over some regions of South Asia, the South American continent, Alaska, around Congo in Africa and over some continental outflows. Significant decrease in TOC is observed over some continents and oceans.
C. von Savigny, F. Ernst, A. Rozanov, R. Hommel, K.-U. Eichmann, V. Rozanov, J. P. Burrows, and L. W. Thomason
Atmos. Meas. Tech., 8, 5223–5235, https://doi.org/10.5194/amt-8-5223-2015, https://doi.org/10.5194/amt-8-5223-2015, 2015
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This article presents validation results for stratospheric aerosol extinction profiles retrieved from limb-scatter measurements with the SCIAMACHY instrument on the Envisat satellite. The SCIAMACHY retrievals are compared to co-located measurements with the SAGE II instrument. Very good agreement to within about 15% is found in a global average sense at altitudes above 15 km. The article also presents sample results on the global morphology of the stratospheric aerosol layer from 2003 to 2011.
O. Lednyts'kyy, C. von Savigny, K.-U. Eichmann, and M. G. Mlynczak
Atmos. Meas. Tech., 8, 1021–1041, https://doi.org/10.5194/amt-8-1021-2015, https://doi.org/10.5194/amt-8-1021-2015, 2015
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This paper deals with the retrieval of atomic oxygen concentration profiles in the Earth's upper mesosphere/lower thermosphere region from SCIAMACHY observations of oxygen green line airglow emissions. Atomic oxygen is one of the most important chemical constituents of this atmospheric region, and long-term satellite data sets are rare. The paper includes a detailed description of the retrieval algorithm, an error budget, validation results and some first scientific analyses.
M. P. Langowski, C. von Savigny, J. P. Burrows, W. Feng, J. M. C. Plane, D. R. Marsh, D. Janches, M. Sinnhuber, A. C. Aikin, and P. Liebing
Atmos. Chem. Phys., 15, 273–295, https://doi.org/10.5194/acp-15-273-2015, https://doi.org/10.5194/acp-15-273-2015, 2015
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Global concentration fields of Mg and Mg+ in the Earth's upper mesosphere and lower thermosphere (70-150km) are presented. These are retrieved from SCIAMACHY/Envisat satellite grating spectrometer measurements in limb viewing geometry between 2008 and 2012.
These were compared with WACCM-Mg model results and a large fraction of the available measurement results for these species, and an interpretation of the results is done. The variation of these species during NLC presence is discussed.
S. Kowalewski, C. von Savigny, M. Palm, I. C. McDade, and J. Notholt
Atmos. Chem. Phys., 14, 10193–10210, https://doi.org/10.5194/acp-14-10193-2014, https://doi.org/10.5194/acp-14-10193-2014, 2014
F. Ebojie, C. von Savigny, A. Ladstätter-Weißenmayer, A. Rozanov, M. Weber, K.-U. Eichmann, S. Bötel, N. Rahpoe, H. Bovensmann, and J. P. Burrows
Atmos. Meas. Tech., 7, 2073–2096, https://doi.org/10.5194/amt-7-2073-2014, https://doi.org/10.5194/amt-7-2073-2014, 2014
B. Hassler, I. Petropavlovskikh, J. Staehelin, T. August, P. K. Bhartia, C. Clerbaux, D. Degenstein, M. De Mazière, B. M. Dinelli, A. Dudhia, G. Dufour, S. M. Frith, L. Froidevaux, S. Godin-Beekmann, J. Granville, N. R. P. Harris, K. Hoppel, D. Hubert, Y. Kasai, M. J. Kurylo, E. Kyrölä, J.-C. Lambert, P. F. Levelt, C. T. McElroy, R. D. McPeters, R. Munro, H. Nakajima, A. Parrish, P. Raspollini, E. E. Remsberg, K. H. Rosenlof, A. Rozanov, T. Sano, Y. Sasano, M. Shiotani, H. G. J. Smit, G. Stiller, J. Tamminen, D. W. Tarasick, J. Urban, R. J. van der A, J. P. Veefkind, C. Vigouroux, T. von Clarmann, C. von Savigny, K. A. Walker, M. Weber, J. Wild, and J. M. Zawodny
Atmos. Meas. Tech., 7, 1395–1427, https://doi.org/10.5194/amt-7-1395-2014, https://doi.org/10.5194/amt-7-1395-2014, 2014
R. Hommel, K.-U. Eichmann, J. Aschmann, K. Bramstedt, M. Weber, C. von Savigny, A. Richter, A. Rozanov, F. Wittrock, F. Khosrawi, R. Bauer, and J. P. Burrows
Atmos. Chem. Phys., 14, 3247–3276, https://doi.org/10.5194/acp-14-3247-2014, https://doi.org/10.5194/acp-14-3247-2014, 2014
M. Langowski, M. Sinnhuber, A. C. Aikin, C. von Savigny, and J. P. Burrows
Atmos. Meas. Tech., 7, 29–48, https://doi.org/10.5194/amt-7-29-2014, https://doi.org/10.5194/amt-7-29-2014, 2014
N. Rahpoe, C. von Savigny, M. Weber, A.V. Rozanov, H. Bovensmann, and J. P. Burrows
Atmos. Meas. Tech., 6, 2825–2837, https://doi.org/10.5194/amt-6-2825-2013, https://doi.org/10.5194/amt-6-2825-2013, 2013
Carlo Arosio, Viktoria Sofieva, Andrea Orfanoz-Cheuquelaf, Alexei Rozanov, Klaus-Peter Heue, Edward Malina, Ryan M. Stauffer, David Tarasick, Roeland Van Malderen, Jerry R. Ziemke, and Mark Weber
EGUsphere, https://doi.org/10.5194/egusphere-2024-3737, https://doi.org/10.5194/egusphere-2024-3737, 2024
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Tropospheric ozone affects air quality and climate, being a pollutant and a greenhouse gas. We analysed satellite data of tropospheric ozone that combine two types of observations: one providing stratospheric ozone and another measuring total ozone. We compare common climatological features and study the influence of the tropopause (troposphere to stratosphere boundary) on the results. We also examine trends over the last 20 years and compare satellite data with ozonesondes to identify drifts.
Alexei Rozanov, Christine Pohl, Carlo Arosio, Adam Bourassa, Klaus Bramstedt, Elizaveta Malinina, Landon Rieger, and John P. Burrows
Atmos. Meas. Tech., 17, 6677–6695, https://doi.org/10.5194/amt-17-6677-2024, https://doi.org/10.5194/amt-17-6677-2024, 2024
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We developed a new algorithm to retrieve vertical distributions of aerosol extinction coefficients in the stratosphere. The algorithm is applied to measurements of scattered solar light from the spaceborne OMPS-LP (Ozone Mapper and Profiler Suite Limb Profiler) instrument. The retrieval results are compared to data from other spaceborne instruments and used to investigate the evolution of the aerosol plume following the eruption of the Hunga Tonga–Hunga Ha'apai volcano in January 2022.
Sandra Wallis, Matthew DeLand, and Christian von Savigny
EGUsphere, https://doi.org/10.5194/egusphere-2024-2165, https://doi.org/10.5194/egusphere-2024-2165, 2024
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The 2022 Hunga eruption emitted about 150 Tg H2O that partly reached the upper polar SH mesosphere in the beginning of 2024. Noctilucent clouds (NLC) did not show a clear perturbation in their occurrence frequency, but the slight increase from mid-January to February could potentially be caused by the additional H2O. It needs 2 years to reach the summer polar mesopause region, analogous to the 1883 Krakatau eruption that is argued to have caused the first sightings of NCLs.
Felix Wrana, Terry Deshler, Christian Löns, Larry W. Thomason, and Christian von Savigny
EGUsphere, https://doi.org/10.5194/egusphere-2024-2942, https://doi.org/10.5194/egusphere-2024-2942, 2024
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There is a natural and globally occurring layer of small droplets (aerosols) in roughly 20 km altitude in the atmosphere. In this work, the size of these aerosols is calculated from satellite measurements for the years 2002 to 2005, which is important for the aerosols cooling effect on Earth's climate. These years are interesting, because there were no large volcanic eruptions that would change the background state of the aerosols. The results are compared to reliable balloon-borne measurements.
Falco Monsees, Alexei Rozanov, John P. Burrows, Mark Weber, Annette Rinke, Ralf Jaiser, and Peter von der Gathen
Atmos. Chem. Phys., 24, 9085–9099, https://doi.org/10.5194/acp-24-9085-2024, https://doi.org/10.5194/acp-24-9085-2024, 2024
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Cyclones strongly influence weather predictability but still cannot be fully characterised in the Arctic because of the sparse coverage of meteorological measurements. A potential approach to compensate for this is the use of satellite measurements of ozone, because cyclones impact the tropopause and therefore also ozone. In this study we used this connection to investigate the correlation between ozone and the tropopause in the Arctic and to identify cyclones with satellite ozone observations.
Christine Pohl, Felix Wrana, Alexei Rozanov, Terry Deshler, Elizaveta Malinina, Christian von Savigny, Landon A. Rieger, Adam E. Bourassa, and John P. Burrows
Atmos. Meas. Tech., 17, 4153–4181, https://doi.org/10.5194/amt-17-4153-2024, https://doi.org/10.5194/amt-17-4153-2024, 2024
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Knowledge of stratospheric aerosol characteristics is important for understanding chemical and climate aerosol feedbacks. Two particle size distribution parameters, the aerosol extinction coefficient and the effective radius, are obtained from SCIAMACHY limb observations. The aerosol characteristics show good agreement with independent data sets from balloon-borne and satellite observations. This data set expands the limited knowledge of stratospheric aerosol characteristics.
Matthew S. Johnson, Alexei Rozanov, Mark Weber, Nora Mettig, John Sullivan, Michael J. Newchurch, Shi Kuang, Thierry Leblanc, Fernando Chouza, Timothy A. Berkoff, Guillaume Gronoff, Kevin B. Strawbridge, Raul J. Alvarez, Andrew O. Langford, Christoph J. Senff, Guillaume Kirgis, Brandi McCarty, and Larry Twigg
Atmos. Meas. Tech., 17, 2559–2582, https://doi.org/10.5194/amt-17-2559-2024, https://doi.org/10.5194/amt-17-2559-2024, 2024
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Monitoring tropospheric ozone (O3), a harmful pollutant negatively impacting human health, is primarily done using ground-based measurements and ozonesondes. However, these observation types lack the coverage to fully understand tropospheric O3. Satellites can retrieve tropospheric ozone with near-daily global coverage; however, they are known to have biases and errors. This study uses ground-based lidars to validate multiple satellites' ability to observe tropospheric O3.
Andrea Orfanoz-Cheuquelaf, Carlo Arosio, Alexei Rozanov, Mark Weber, Annette Ladstätter-Weißenmayer, John P. Burrows, Anne M. Thompson, Ryan M. Stauffer, and Debra E. Kollonige
Atmos. Meas. Tech., 17, 1791–1809, https://doi.org/10.5194/amt-17-1791-2024, https://doi.org/10.5194/amt-17-1791-2024, 2024
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Valuable information on the tropospheric ozone column (TrOC) can be obtained globally by combining space-borne limb and nadir measurements (limb–nadir matching, LNM). This study describes the retrieval of TrOC from the OMPS instrument (since 2012) using the LNM technique. The OMPS-LNM TrOC was compared with ozonesondes and other satellite measurements, showing a good agreement with a negative bias within 1 to 4 DU. This new dataset is suitable for pollution studies.
Christian von Savigny, Anna Lange, Christoph G. Hoffmann, and Alexei Rozanov
Atmos. Chem. Phys., 24, 2415–2422, https://doi.org/10.5194/acp-24-2415-2024, https://doi.org/10.5194/acp-24-2415-2024, 2024
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It is well known that volcanic eruptions strongly affect the colours of the twilight sky. Typically, volcanic eruptions lead to enhanced reddish and violet twilight colours. In rare cases, however, volcanic eruptions can also lead to green sunsets. This study provides an explanation for the occurrence of these unusual green sunsets based on simulations with a radiative transfer model. Green volcanic sunsets require a sufficient stratospheric aerosol optical depth and specific aerosol sizes.
Anna Lange, Alexei Rozanov, and Christian von Savigny
Atmos. Chem. Phys., 23, 14829–14839, https://doi.org/10.5194/acp-23-14829-2023, https://doi.org/10.5194/acp-23-14829-2023, 2023
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We were able to demonstrate quantitatively that the blue colour of the sky cannot be solely attributed to Rayleigh scattering. The influence of ozone on the blue colour of the sky is calculated for different viewing geometries, total ozone columns and an enhanced stratospheric aerosol scenario. Furthermore, the effects of polarisation, surface albedo and observer height are investigated.
John M. C. Plane, Jörg Gumbel, Konstantinos S. Kalogerakis, Daniel R. Marsh, and Christian von Savigny
Atmos. Chem. Phys., 23, 13255–13282, https://doi.org/10.5194/acp-23-13255-2023, https://doi.org/10.5194/acp-23-13255-2023, 2023
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The mesosphere or lower thermosphere region of the atmosphere borders the edge of space. It is subject to extreme ultraviolet photons and charged particles from the Sun and atmospheric gravity waves from below, which tend to break in this region. The pressure is very low, which facilitates chemistry involving species in excited states, and this is also the region where cosmic dust ablates and injects various metals. The result is a unique and exotic chemistry.
Christoph G. Hoffmann, Lena G. Buth, and Christian von Savigny
Atmos. Chem. Phys., 23, 12781–12799, https://doi.org/10.5194/acp-23-12781-2023, https://doi.org/10.5194/acp-23-12781-2023, 2023
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The Madden–Julian oscillation is an important feature of weather in the tropics. Although it is mainly active in the troposphere, we show that it systematically influences the air temperature in the layers above, up to about 100 km altitude and from pole to pole. We have linked this to another known far-reaching process, interhemispheric coupling. This is basic research on atmospheric couplings and variability but might also be of interest for intraseasonal weather forecasting models.
Michael Kiefer, Dale F. Hurst, Gabriele P. Stiller, Stefan Lossow, Holger Vömel, John Anderson, Faiza Azam, Jean-Loup Bertaux, Laurent Blanot, Klaus Bramstedt, John P. Burrows, Robert Damadeo, Bianca Maria Dinelli, Patrick Eriksson, Maya García-Comas, John C. Gille, Mark Hervig, Yasuko Kasai, Farahnaz Khosrawi, Donal Murtagh, Gerald E. Nedoluha, Stefan Noël, Piera Raspollini, William G. Read, Karen H. Rosenlof, Alexei Rozanov, Christopher E. Sioris, Takafumi Sugita, Thomas von Clarmann, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 16, 4589–4642, https://doi.org/10.5194/amt-16-4589-2023, https://doi.org/10.5194/amt-16-4589-2023, 2023
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We quantify biases and drifts (and their uncertainties) between the stratospheric water vapor measurement records of 15 satellite-based instruments (SATs, with 31 different retrievals) and balloon-borne frost point hygrometers (FPs) launched at 27 globally distributed stations. These comparisons of measurements during the period 2000–2016 are made using robust, consistent statistical methods. With some exceptions, the biases and drifts determined for most SAT–FP pairs are < 10 % and < 1 % yr−1.
Felix Wrana, Ulrike Niemeier, Larry W. Thomason, Sandra Wallis, and Christian von Savigny
Atmos. Chem. Phys., 23, 9725–9743, https://doi.org/10.5194/acp-23-9725-2023, https://doi.org/10.5194/acp-23-9725-2023, 2023
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The stratospheric aerosol layer is a naturally occurring and permanent layer of aerosol, in this case very small droplets of mostly sulfuric acid and water, that has a cooling effect on our climate. To quantify this effect and for our general understanding of stratospheric microphysical processes, knowledge of the size of those aerosol particles is needed. Using satellite measurements and atmospheric models we show that some volcanic eruptions can lead to on average smaller aerosol sizes.
Sandra Wallis, Hauke Schmidt, and Christian von Savigny
Atmos. Chem. Phys., 23, 7001–7014, https://doi.org/10.5194/acp-23-7001-2023, https://doi.org/10.5194/acp-23-7001-2023, 2023
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Strong volcanic eruptions are able to alter the temperature and the circulation of the middle atmosphere. This study simulates the atmospheric response to an idealized strong tropical eruption and focuses on the impact on the mesosphere. The simulations show a warming of the polar summer mesopause in the first November after the eruption. Our study indicates that this is mainly due to dynamical coupling in the summer hemisphere with a potential contribution from interhemispheric coupling.
Linlu Mei, Vladimir Rozanov, Alexei Rozanov, and John P. Burrows
Geosci. Model Dev., 16, 1511–1536, https://doi.org/10.5194/gmd-16-1511-2023, https://doi.org/10.5194/gmd-16-1511-2023, 2023
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This paper summarizes recent developments of aerosol, cloud and surface reflectance databases and models in the framework of the software package SCIATRAN. These updates and developments extend the capabilities of the radiative transfer modeling, especially by accounting for different kinds of vertical inhomogeneties. Vertically inhomogeneous clouds and different aerosol types can be easily accounted for within SCIATRAN (V4.6). The widely used surface models and databases are now available.
Carlo Arosio, Alexei Rozanov, Victor Gorshelev, Alexandra Laeng, and John P. Burrows
Atmos. Meas. Tech., 15, 5949–5967, https://doi.org/10.5194/amt-15-5949-2022, https://doi.org/10.5194/amt-15-5949-2022, 2022
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This paper characterizes the uncertainties affecting the ozone profiles retrieved at the University of Bremen through OMPS limb satellite observations. An accurate knowledge of the uncertainties is relevant for the validation of the product and to correctly interpret the retrieval results. We investigate several sources of uncertainties, estimate a total random and systematic component, and verify the consistency of the combined OMPS-MLS total uncertainty.
John T. Sullivan, Arnoud Apituley, Nora Mettig, Karin Kreher, K. Emma Knowland, Marc Allaart, Ankie Piters, Michel Van Roozendael, Pepijn Veefkind, Jerry R. Ziemke, Natalya Kramarova, Mark Weber, Alexei Rozanov, Laurence Twigg, Grant Sumnicht, and Thomas J. McGee
Atmos. Chem. Phys., 22, 11137–11153, https://doi.org/10.5194/acp-22-11137-2022, https://doi.org/10.5194/acp-22-11137-2022, 2022
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A TROPOspheric Monitoring Instrument (TROPOMI) validation campaign (TROLIX-19) was held in the Netherlands in September 2019. The research presented here focuses on using ozone lidars from NASA’s Goddard Space Flight Center to better evaluate the characterization of ozone throughout TROLIX-19 as compared to balloon-borne, space-borne and ground-based passive measurements, as well as a global coupled chemistry meteorology model.
Sandra Wallis, Christoph Gregor Hoffmann, and Christian von Savigny
Ann. Geophys., 40, 421–431, https://doi.org/10.5194/angeo-40-421-2022, https://doi.org/10.5194/angeo-40-421-2022, 2022
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Although the 1991 eruption of Mt Pinatubo had a severe impact on Earth's climate, the effect of this event on the mesosphere is not well understood. We investigated satellite-borne temperature measurements from the HALOE instrument and found indications that a positive temperature anomaly is present in the tropical upper mesosphere at the beginning of the HALOE time series, which may be related to the eruption of Mt. Pinatubo.
Anna Lange, Gerd Baumgarten, Alexei Rozanov, and Christian von Savigny
Ann. Geophys., 40, 407–419, https://doi.org/10.5194/angeo-40-407-2022, https://doi.org/10.5194/angeo-40-407-2022, 2022
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We investigate the influence of different parameters on the colour of noctilucent clouds (highest clouds in the atmosphere), using radiative transfer calculations. We determined the effect of the particle size, optical depth, single scattering/multiple scattering and ozone. For sufficiently large optical depth and for specific viewing geometries, ozone plays only a minor role in the blueish colour of noctilucent clouds (new result).
William G. Read, Gabriele Stiller, Stefan Lossow, Michael Kiefer, Farahnaz Khosrawi, Dale Hurst, Holger Vömel, Karen Rosenlof, Bianca M. Dinelli, Piera Raspollini, Gerald E. Nedoluha, John C. Gille, Yasuko Kasai, Patrick Eriksson, Christopher E. Sioris, Kaley A. Walker, Katja Weigel, John P. Burrows, and Alexei Rozanov
Atmos. Meas. Tech., 15, 3377–3400, https://doi.org/10.5194/amt-15-3377-2022, https://doi.org/10.5194/amt-15-3377-2022, 2022
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This paper attempts to provide an assessment of the accuracy of 21 satellite-based instruments that remotely measure atmospheric humidity in the upper troposphere of the Earth's atmosphere. The instruments made their measurements from 1984 to the present time; however, most of these instruments began operations after 2000, and only a few are still operational. The objective of this study is to quantify the accuracy of each satellite humidity data set.
Nora Mettig, Mark Weber, Alexei Rozanov, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Ryan M. Stauffer, Thierry Leblanc, Gerard Ancellet, Michael J. Newchurch, Shi Kuang, Rigel Kivi, Matthew B. Tully, Roeland Van Malderen, Ankie Piters, Bogumil Kois, René Stübi, and Pavla Skrivankova
Atmos. Meas. Tech., 15, 2955–2978, https://doi.org/10.5194/amt-15-2955-2022, https://doi.org/10.5194/amt-15-2955-2022, 2022
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Vertical ozone profiles from combined spectral measurements in the UV and IR spectral ranges were retrieved by using data from TROPOMI/S5P and CrIS/Suomi-NPP. The vertical resolution and accuracy of the ozone profiles are improved by combining both wavelength ranges compared to retrievals limited to UV or IR spectral data only. The advancement of our TOPAS algorithm for combined measurements is required because in the UV-only retrieval the vertical resolution in the troposphere is very limited.
Mireia Papke Chica, Valerian Hahn, Tiziana Braeuer, Elena de la Torre Castro, Florian Ewald, Mathias Gergely, Simon Kirschler, Luca Bugliaro Goggia, Stefanie Knobloch, Martina Kraemer, Johannes Lucke, Johanna Mayer, Raphael Maerkl, Manuel Moser, Laura Tomsche, Tina Jurkat-Witschas, Martin Zoeger, Christian von Savigny, and Christiane Voigt
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-255, https://doi.org/10.5194/acp-2022-255, 2022
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The mixed-phase temperature regime in convective clouds challenges our understanding of microphysical and radiative cloud properties. We provide a rare and unique dataset of aircraft in situ measurements in a strong mid-latitude convective system. We find that mechanisms initiating ice nucleation and growth strongly depend on temperature, relative humidity, and vertical velocity and variate within the measured system, resulting in altitude dependent changes of the cloud liquid and ice fraction.
Julia Koch, Adam Bourassa, Nick Lloyd, Chris Roth, and Christian von Savigny
Atmos. Chem. Phys., 22, 3191–3202, https://doi.org/10.5194/acp-22-3191-2022, https://doi.org/10.5194/acp-22-3191-2022, 2022
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The mesopause, the region of the earth's atmosphere between 85 and 100 km, is hard to access by direct measurements. Therefore we look for parameters that can be measured using satellite or ground-based measurements. In this study we researched sodium airglow, a phenomenon that occurs when sodium atoms are excited by chemical reactions. We compared satellite measurements of the airglow and resulting sodium concentration profiles to gain a better understanding of the sodium in that region.
Sandip S. Dhomse, Carlo Arosio, Wuhu Feng, Alexei Rozanov, Mark Weber, and Martyn P. Chipperfield
Earth Syst. Sci. Data, 13, 5711–5729, https://doi.org/10.5194/essd-13-5711-2021, https://doi.org/10.5194/essd-13-5711-2021, 2021
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High-quality long-term ozone profile data sets are key to estimating short- and long-term ozone variability. Almost all the satellite (and chemical model) data sets show some kind of bias with respect to each other. This is because of differences in measurement methodologies as well as simplified processes in the models. We use satellite data sets and chemical model output to generate 42 years of ozone profile data sets using a random-forest machine-learning algorithm that is named ML-TOMCAT.
Elizaveta Malinina, Alexei Rozanov, Ulrike Niemeier, Sandra Wallis, Carlo Arosio, Felix Wrana, Claudia Timmreck, Christian von Savigny, and John P. Burrows
Atmos. Chem. Phys., 21, 14871–14891, https://doi.org/10.5194/acp-21-14871-2021, https://doi.org/10.5194/acp-21-14871-2021, 2021
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In the paper, changes in the stratospheric aerosol loading after the 2018 Ambae eruption were analyzed using OMPS-LP observations. The eruption was also simulated with the MAECHAM5-HAM global climate model. Generally, the model and observations agree very well. We attribute the good consistency of the results to a precisely determined altitude and mass of the volcanic injection, as well as nudging of the meteorological data. The radiative forcing from the eruption was estimated to be −0.13 W m−2.
Nora Mettig, Mark Weber, Alexei Rozanov, Carlo Arosio, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Richard Querel, Thierry Leblanc, Sophie Godin-Beekmann, Rigel Kivi, and Matthew B. Tully
Atmos. Meas. Tech., 14, 6057–6082, https://doi.org/10.5194/amt-14-6057-2021, https://doi.org/10.5194/amt-14-6057-2021, 2021
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TROPOMI is a nadir-viewing satellite that has observed global atmospheric trace gases at unprecedented spatial resolution since 2017. The retrieval of ozone profiles with high accuracy has been demonstrated using the TOPAS (Tikhonov regularised Ozone Profile retrievAl with SCIATRAN) algorithm and applying appropriate spectral corrections to TROPOMI UV data. Ozone profiles from TROPOMI were compared to ozonesonde and lidar profiles, showing an agreement to within 5 % in the stratosphere.
Andrea Orfanoz-Cheuquelaf, Alexei Rozanov, Mark Weber, Carlo Arosio, Annette Ladstätter-Weißenmayer, and John P. Burrows
Atmos. Meas. Tech., 14, 5771–5789, https://doi.org/10.5194/amt-14-5771-2021, https://doi.org/10.5194/amt-14-5771-2021, 2021
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OMPS/NPP (2012–present) allows obtaining the tropospheric ozone column by combining ozone data from limb and nadir observations from the same instrument platform. In a first step, the retrieval of the total ozone column from the OMPS Nadir Mapper using the weighting function fitting approach (WFFA) is described here. The OMPS total ozone was compared with ground-based and other satellite measurements, showing agreement within 2.5 %.
Daniel Zawada, Ghislain Franssens, Robert Loughman, Antti Mikkonen, Alexei Rozanov, Claudia Emde, Adam Bourassa, Seth Dueck, Hannakaisa Lindqvist, Didier Ramon, Vladimir Rozanov, Emmanuel Dekemper, Erkki Kyrölä, John P. Burrows, Didier Fussen, and Doug Degenstein
Atmos. Meas. Tech., 14, 3953–3972, https://doi.org/10.5194/amt-14-3953-2021, https://doi.org/10.5194/amt-14-3953-2021, 2021
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Satellite measurements of atmospheric composition often rely on computer tools known as radiative transfer models to model the propagation of sunlight within the atmosphere. Here we have performed a detailed inter-comparison of seven different radiative transfer models in a variety of conditions. We have found that the models agree remarkably well, at a level better than previously reported. This result provides confidence in our understanding of atmospheric radiative transfer.
Michaela I. Hegglin, Susann Tegtmeier, John Anderson, Adam E. Bourassa, Samuel Brohede, Doug Degenstein, Lucien Froidevaux, Bernd Funke, John Gille, Yasuko Kasai, Erkki T. Kyrölä, Jerry Lumpe, Donal Murtagh, Jessica L. Neu, Kristell Pérot, Ellis E. Remsberg, Alexei Rozanov, Matthew Toohey, Joachim Urban, Thomas von Clarmann, Kaley A. Walker, Hsiang-Jui Wang, Carlo Arosio, Robert Damadeo, Ryan A. Fuller, Gretchen Lingenfelser, Christopher McLinden, Diane Pendlebury, Chris Roth, Niall J. Ryan, Christopher Sioris, Lesley Smith, and Katja Weigel
Earth Syst. Sci. Data, 13, 1855–1903, https://doi.org/10.5194/essd-13-1855-2021, https://doi.org/10.5194/essd-13-1855-2021, 2021
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An overview of the SPARC Data Initiative is presented, to date the most comprehensive assessment of stratospheric composition measurements spanning 1979–2018. Measurements of 26 chemical constituents obtained from an international suite of space-based limb sounders were compiled into vertically resolved, zonal monthly mean time series. The quality and consistency of these gridded datasets are then evaluated using a climatological validation approach and a range of diagnostics.
Nellie Wullenweber, Anna Lange, Alexei Rozanov, and Christian von Savigny
Clim. Past, 17, 969–983, https://doi.org/10.5194/cp-17-969-2021, https://doi.org/10.5194/cp-17-969-2021, 2021
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This study investigates the physical processes leading to the rare phenomenon of the sun appearing blue or green. The phenomenon is caused by anomalous scattering by, e.g., volcanic or forest fire aerosols. Unlike most other studies, our study includes a full treatment of the effect of Rayleigh scattering on the colour of the sun. We investigate different factors and revisit a historic example, i.e. the Canadian forest fires in 1950, that led to blue sun events in different European countries.
Felix Wrana, Christian von Savigny, Jacob Zalach, and Larry W. Thomason
Atmos. Meas. Tech., 14, 2345–2357, https://doi.org/10.5194/amt-14-2345-2021, https://doi.org/10.5194/amt-14-2345-2021, 2021
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In this paper, we describe a new method for calculating the size of naturally occurring droplets (aerosols) made mostly of sulfuric acid and water that can be found roughly at 20 km altitude in the atmosphere. We use data from the instrument SAGE III/ISS that is mounted on the International Space Station. We show that our method works well, and that the size parameters we calculate are reasonable and can be a valuable addition for a better understanding of aerosols and their effect on climate.
Larry W. Thomason, Mahesh Kovilakam, Anja Schmidt, Christian von Savigny, Travis Knepp, and Landon Rieger
Atmos. Chem. Phys., 21, 1143–1158, https://doi.org/10.5194/acp-21-1143-2021, https://doi.org/10.5194/acp-21-1143-2021, 2021
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Measurements of the impact of volcanic eruptions on stratospheric aerosol loading by space-based instruments show show a fairly well-behaved relationship between the magnitude and the apparent changes to aerosol size over several orders of magnitude. This directly measured relationship provides a unique opportunity to verify the performance of interactive aerosol models used in climate models.
Lukas O. Muser, Gholam Ali Hoshyaripour, Julia Bruckert, Ákos Horváth, Elizaveta Malinina, Sandra Wallis, Fred J. Prata, Alexei Rozanov, Christian von Savigny, Heike Vogel, and Bernhard Vogel
Atmos. Chem. Phys., 20, 15015–15036, https://doi.org/10.5194/acp-20-15015-2020, https://doi.org/10.5194/acp-20-15015-2020, 2020
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Volcanic aerosols endanger aircraft and thus disrupt air travel globally. For aviation safety, it is vital to know the location and lifetime of such aerosols in the atmosphere. Here we show that the interaction of volcanic particles with each other eventually reduces their atmospheric lifetime. Moreover, we demonstrate that sunlight heats these particles, which lifts them several kilometers in the atmosphere. These findings support a more reliable forecast of volcanic aerosol dispersion.
Stefan Noël, Klaus Bramstedt, Alexei Rozanov, Elizaveta Malinina, Heinrich Bovensmann, and John P. Burrows
Atmos. Meas. Tech., 13, 5643–5666, https://doi.org/10.5194/amt-13-5643-2020, https://doi.org/10.5194/amt-13-5643-2020, 2020
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A new approach to derive stratospheric aerosol extinction profiles from SCIAMACHY solar occultation measurements based on an onion-peeling method is presented. The resulting extinctions at 452, 525 and 750 nm compare well with other limb and occultation data from, e.g. SAGE and SCIAMACHY, but show small oscillating features which vanish in monthly anomalies. Major volcanic eruptions, polar stratospheric clouds and influences of the quasi-biennial oscillation can be identified in the time series.
Thomas von Clarmann, Douglas A. Degenstein, Nathaniel J. Livesey, Stefan Bender, Amy Braverman, André Butz, Steven Compernolle, Robert Damadeo, Seth Dueck, Patrick Eriksson, Bernd Funke, Margaret C. Johnson, Yasuko Kasai, Arno Keppens, Anne Kleinert, Natalya A. Kramarova, Alexandra Laeng, Bavo Langerock, Vivienne H. Payne, Alexei Rozanov, Tomohiro O. Sato, Matthias Schneider, Patrick Sheese, Viktoria Sofieva, Gabriele P. Stiller, Christian von Savigny, and Daniel Zawada
Atmos. Meas. Tech., 13, 4393–4436, https://doi.org/10.5194/amt-13-4393-2020, https://doi.org/10.5194/amt-13-4393-2020, 2020
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Remote sensing of atmospheric state variables typically relies on the inverse solution of the radiative transfer equation. An adequately characterized retrieval provides information on the uncertainties of the estimated state variables as well as on how any constraint or a priori assumption affects the estimate. This paper summarizes related techniques and provides recommendations for unified error reporting.
Christian von Savigny and Christoph G. Hoffmann
Atmos. Meas. Tech., 13, 1909–1920, https://doi.org/10.5194/amt-13-1909-2020, https://doi.org/10.5194/amt-13-1909-2020, 2020
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Stratospheric sulfate aerosols increase the Earth's planetary albedo and can lead to significant surface cooling, for example in the aftermath of volcanic eruptions. Their particle size distribution, important for physical and chemical effects of these aerosols, is still not fully understood. The present paper proposes an explanation for systematic differences in aerosol particle size retrieved from measurements made in different measurement geometries and reported in earlier studies.
Olexandr Lednyts'kyy and Christian von Savigny
Atmos. Chem. Phys., 20, 2221–2261, https://doi.org/10.5194/acp-20-2221-2020, https://doi.org/10.5194/acp-20-2221-2020, 2020
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Atomic oxygen is a chemically active trace gas and a critical component of the energy balance of the mesosphere and lower thermosphere (MLT). By sequentially applying continuity equations of low degree, a new model representing the airglow and photochemistry of oxygen in the MLT is implemented, enabling comparisons with airglow observations at each step. The most effective data sets required to derive the abundance of atomic oxygen are the O2 atmospheric band emission, temperature, N2 and O2.
Piao Rong, Christian von Savigny, Chunmin Zhang, Christoph G. Hoffmann, and Michael J. Schwartz
Atmos. Chem. Phys., 20, 1737–1755, https://doi.org/10.5194/acp-20-1737-2020, https://doi.org/10.5194/acp-20-1737-2020, 2020
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We study the presence and characteristics of 27 d solar signatures in middle atmospheric temperature observed by the microwave limb sounder on NASA's Aura spacecraft. This is a highly interesting and significant subject because the physical and chemical mechanisms leading to these 27 d solar-driven signatures are, in many cases, not well understood. The analysis shows that highly significant 27 d solar signatures in middle atmospheric temperature are present at many altitudes and latitudes.
Niall J. Ryan, Mathias Palm, Christoph G. Hoffmann, Jens Goliasch, and Justus Notholt
Atmos. Meas. Tech., 12, 4077–4089, https://doi.org/10.5194/amt-12-4077-2019, https://doi.org/10.5194/amt-12-4077-2019, 2019
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We present a new ground-based instrument (CORAM) that measures atmospheric carbon monoxide (CO) concentrations within approximately 47–87 km in altitude with a 1 h time resolution. The measurements are made at Ny-Ålesund (79° N), Svalbard, and add much-needed coverage to the high Arctic. The first measured CO profiles from winter 2017/2018 are compared to co-located measurements from the Aura MLS satellite instrument and show agreement on daily and monthly timescales.
Jacob Zalach, Christian von Savigny, Arvid Langenbach, Gerd Baumgarten, Franz-Josef Lübken, and Adam Bourassa
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-267, https://doi.org/10.5194/amt-2019-267, 2019
Revised manuscript not accepted
Arvid Langenbach, Gerd Baumgarten, Jens Fiedler, Franz-Josef Lübken, Christian von Savigny, and Jacob Zalach
Atmos. Meas. Tech., 12, 4065–4076, https://doi.org/10.5194/amt-12-4065-2019, https://doi.org/10.5194/amt-12-4065-2019, 2019
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Stratospheric aerosol backscatter ratios in the Arctic using Rayleigh, Mie and Raman backscattered signals were calculated. A backscatter ratio calculation during daytime was performed for the first time. Sharp aerosol layers thinner than 1 km over several days were observed. The seasonal cycle of stratospheric background aerosol in high latitudes including the summer months was calculated for the first time. Top altitude of the aerosol layer was found to reach up to 34 km, especially in summer.
Dan Weaver, Kimberly Strong, Kaley A. Walker, Chris Sioris, Matthias Schneider, C. Thomas McElroy, Holger Vömel, Michael Sommer, Katja Weigel, Alexei Rozanov, John P. Burrows, William G. Read, Evan Fishbein, and Gabriele Stiller
Atmos. Meas. Tech., 12, 4039–4063, https://doi.org/10.5194/amt-12-4039-2019, https://doi.org/10.5194/amt-12-4039-2019, 2019
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This work assesses water vapour profiles acquired by Atmospheric Chemistry Experiment (ACE) satellite instruments in the upper troposphere and lower stratosphere (UTLS) using comparisons to radiosondes and ground-based Fourier transform infrared spectrometer measurements acquired at a Canadian high Arctic measurement site in Eureka, Nunavut. Additional comparisons are made between these Eureka measurements and other water vapour satellite datasets for context, including AIRS, MLS, and others.
Elizaveta Malinina, Alexei Rozanov, Landon Rieger, Adam Bourassa, Heinrich Bovensmann, John P. Burrows, and Doug Degenstein
Atmos. Meas. Tech., 12, 3485–3502, https://doi.org/10.5194/amt-12-3485-2019, https://doi.org/10.5194/amt-12-3485-2019, 2019
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This paper covers the problems related to the derivation of aerosol extinction coefficients and Ångström exponents from space-borne instruments working in limb and occultation viewing geometries. Aerosol extinction coefficients and Ångström exponents were calculated from the SCIAMACHY aerosol particle size data set. The results were compared with the data from SAGE II and OSIRIS. The Ångström exponent in the tropical regions and its dependency on particle size parameters are discussed.
Stefan Lossow, Farahnaz Khosrawi, Michael Kiefer, Kaley A. Walker, Jean-Loup Bertaux, Laurent Blanot, James M. Russell, Ellis E. Remsberg, John C. Gille, Takafumi Sugita, Christopher E. Sioris, Bianca M. Dinelli, Enzo Papandrea, Piera Raspollini, Maya García-Comas, Gabriele P. Stiller, Thomas von Clarmann, Anu Dudhia, William G. Read, Gerald E. Nedoluha, Robert P. Damadeo, Joseph M. Zawodny, Katja Weigel, Alexei Rozanov, Faiza Azam, Klaus Bramstedt, Stefan Noël, John P. Burrows, Hideo Sagawa, Yasuko Kasai, Joachim Urban, Patrick Eriksson, Donal P. Murtagh, Mark E. Hervig, Charlotta Högberg, Dale F. Hurst, and Karen H. Rosenlof
Atmos. Meas. Tech., 12, 2693–2732, https://doi.org/10.5194/amt-12-2693-2019, https://doi.org/10.5194/amt-12-2693-2019, 2019
Carlo Arosio, Alexei Rozanov, Elizaveta Malinina, Mark Weber, and John P. Burrows
Atmos. Meas. Tech., 12, 2423–2444, https://doi.org/10.5194/amt-12-2423-2019, https://doi.org/10.5194/amt-12-2423-2019, 2019
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The aim of this study is the merging of stratospheric ozone profiles from three satellite data sets. The merged time series is used to compute long-term changes as a function of altitude, latitude and longitude to study the evolution of the ozone layer over 1985–2018. During the last 16 years we found positive trends in the upper stratosphere at mid latitudes, a large variability of the ozone changes as a function of longitude and a fluctuation in the tropical middle stratospheric trend.
Christoph G. Hoffmann and Christian von Savigny
Atmos. Chem. Phys., 19, 4235–4256, https://doi.org/10.5194/acp-19-4235-2019, https://doi.org/10.5194/acp-19-4235-2019, 2019
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We examine a possible statistical linkage between atmospheric variability in the tropical troposphere on the intraseasonal timescale, which is known as Madden–Julian oscillation, and known variability of the solar radiation with a period of 27 days. This helps to understand tropospheric variability in more detail, which is generally of interest, e.g., for weather forecasting. We find indications for such a linkage; however, more research has to be conducted for an unambiguous attribution.
Christian von Savigny, Dieter H. W. Peters, and Günter Entzian
Atmos. Chem. Phys., 19, 2079–2093, https://doi.org/10.5194/acp-19-2079-2019, https://doi.org/10.5194/acp-19-2079-2019, 2019
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This study investigates solar effects in radio reflection height observations in the ionospheric D region at an altitude of about 80 km at northern midlatitudes. The analyzed time series covers almost six solar cycles. Statistically significant solar 27-day and 11-year signatures are identified. However, the driving mechanisms are not fully understood. We also provide evidence for dynamical effects on the radio reflection heights with periods close to the solar rotational cycle.
Tilo Fytterer, Christian von Savigny, Martin Mlynczak, and Miriam Sinnhuber
Atmos. Chem. Phys., 19, 1835–1851, https://doi.org/10.5194/acp-19-1835-2019, https://doi.org/10.5194/acp-19-1835-2019, 2019
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A model was developed to derive night-time atomic oxygen (O(3P)) and atomic hydrogen (H) from satellite observations in the altitude region between 75 km and 100 km. Comparisons between the
best-fit modeland the measurements suggest that chemical reactions involving O2 and O(3P) might occur differently than is usually assumed in literature. This considerably affects the derived abundances of O(3P) and H, which in turn might influence air temperature and winds of the whole atmosphere.
Evgenia Galytska, Alexey Rozanov, Martyn P. Chipperfield, Sandip. S. Dhomse, Mark Weber, Carlo Arosio, Wuhu Feng, and John P. Burrows
Atmos. Chem. Phys., 19, 767–783, https://doi.org/10.5194/acp-19-767-2019, https://doi.org/10.5194/acp-19-767-2019, 2019
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In this study we analysed ozone changes in the tropical mid-stratosphere as observed by the SCIAMACHY instrument during 2004–2012. We used simulations from TOMCAT model with different chemical and dynamical forcings to reveal primary causes of ozone changes. We also considered measured NO2 and modelled NOx, NOx, and N2O data. With modelled AoA data we identified seasonal changes in the upwelling speed and explained how those changes affect N2O chemistry which leads to observed ozone changes.
Tim Bösch, Vladimir Rozanov, Andreas Richter, Enno Peters, Alexei Rozanov, Folkard Wittrock, Alexis Merlaud, Johannes Lampel, Stefan Schmitt, Marijn de Haij, Stijn Berkhout, Bas Henzing, Arnoud Apituley, Mirjam den Hoed, Jan Vonk, Martin Tiefengraber, Moritz Müller, and John Philip Burrows
Atmos. Meas. Tech., 11, 6833–6859, https://doi.org/10.5194/amt-11-6833-2018, https://doi.org/10.5194/amt-11-6833-2018, 2018
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A new MAX-DOAS profiling algorithm for aerosols and trace
gases was developed.
The performance of this novel algorithm was tested with the help of
synthetic data and measurements from the CINDI-2 campaign in Cabauw, the
Netherlands, in 2016.
Farahnaz Khosrawi, Stefan Lossow, Gabriele P. Stiller, Karen H. Rosenlof, Joachim Urban, John P. Burrows, Robert P. Damadeo, Patrick Eriksson, Maya García-Comas, John C. Gille, Yasuko Kasai, Michael Kiefer, Gerald E. Nedoluha, Stefan Noël, Piera Raspollini, William G. Read, Alexei Rozanov, Christopher E. Sioris, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 11, 4435–4463, https://doi.org/10.5194/amt-11-4435-2018, https://doi.org/10.5194/amt-11-4435-2018, 2018
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Time series of stratospheric and lower mesospheric water vapour using 33 data sets from 15 satellite instruments were compared in the framework of the second SPARC water vapour assessment. We find that most data sets can be considered in observational and modelling studies addressing, e.g. stratospheric and lower mesospheric water vapour variability and trends if data-set-specific characteristics (e.g. a drift) and restrictions (e.g. temporal and spatial coverage) are taken into account.
Landon A. Rieger, Elizaveta P. Malinina, Alexei V. Rozanov, John P. Burrows, Adam E. Bourassa, and Doug A. Degenstein
Atmos. Meas. Tech., 11, 3433–3445, https://doi.org/10.5194/amt-11-3433-2018, https://doi.org/10.5194/amt-11-3433-2018, 2018
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This paper compares aerosol extinction records from two limb scattering instruments, OSIRIS and SCIAMACHY, to that from the occultation instrument SAGE II. Differences are investigated through modelling and retrieval studies and important sources of systematic errors are quantified. It is found that the largest biases come from uncertainties in the aerosol size distribution and the aerosol particle concentration at altitudes above 30 km.
Carlo Arosio, Alexei Rozanov, Elizaveta Malinina, Kai-Uwe Eichmann, Thomas von Clarmann, and John P. Burrows
Atmos. Meas. Tech., 11, 2135–2149, https://doi.org/10.5194/amt-11-2135-2018, https://doi.org/10.5194/amt-11-2135-2018, 2018
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This paper describes the development of a retrieval algorithm at the University of Bremen which derives stratospheric ozone profiles from limb observations performed by the OMPS satellite instrument. Here we present the implementation of the algorithm and the validation of our results (1 year of data against independent satellite and ground-based measurements). Good agreement is generally found between 20 and 55 km, mostly within 10 % at all latitudes.
Elizaveta Malinina, Alexei Rozanov, Vladimir Rozanov, Patricia Liebing, Heinrich Bovensmann, and John P. Burrows
Atmos. Meas. Tech., 11, 2085–2100, https://doi.org/10.5194/amt-11-2085-2018, https://doi.org/10.5194/amt-11-2085-2018, 2018
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Stratospheric aerosols play an important role in climate change. This paper presents the retrieval algorithm of two aerosol particle size distribution parameters in the stratosphere from remote sensing instruments. A unique data set was created by implementing this algorithm on SCIAMACHY limb measurements. The general behaviour of the aerosol particle size parameters was revealed. Comparison of the retrieved parameters with another instrument showed good agreement.
Stefan Noël, Katja Weigel, Klaus Bramstedt, Alexei Rozanov, Mark Weber, Heinrich Bovensmann, and John P. Burrows
Atmos. Chem. Phys., 18, 4463–4476, https://doi.org/10.5194/acp-18-4463-2018, https://doi.org/10.5194/acp-18-4463-2018, 2018
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The combined analysis of stratospheric methane and water vapour data derived from SCIAMACHY solar occultation measurements shows the expected anti-correlation and a clear temporal variation related to waves in equatorial zonal winds. Above about 20 km most of the additional water vapour is attributed to the oxidation of methane. The SCIAMACHY data confirm that at lower altitudes water vapour and methane are transported from the tropics to higher latitudes.
Niall J. Ryan, Douglas E. Kinnison, Rolando R. Garcia, Christoph G. Hoffmann, Mathias Palm, Uwe Raffalski, and Justus Notholt
Atmos. Chem. Phys., 18, 1457–1474, https://doi.org/10.5194/acp-18-1457-2018, https://doi.org/10.5194/acp-18-1457-2018, 2018
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We used model output and instrument data to assess how well polar atmospheric descent rates can be derived using concentration measurements of long-lived gases in the atmosphere. The results indicate that the method incurs errors as large as the descent rates, and often leads to a misinterpretation of the direction of air motion. The rates derived using this method do not appear to represent the mean vertical wind in the middle atmosphere, and we suggest an alternate definition.
Wolfgang Steinbrecht, Lucien Froidevaux, Ryan Fuller, Ray Wang, John Anderson, Chris Roth, Adam Bourassa, Doug Degenstein, Robert Damadeo, Joe Zawodny, Stacey Frith, Richard McPeters, Pawan Bhartia, Jeannette Wild, Craig Long, Sean Davis, Karen Rosenlof, Viktoria Sofieva, Kaley Walker, Nabiz Rahpoe, Alexei Rozanov, Mark Weber, Alexandra Laeng, Thomas von Clarmann, Gabriele Stiller, Natalya Kramarova, Sophie Godin-Beekmann, Thierry Leblanc, Richard Querel, Daan Swart, Ian Boyd, Klemens Hocke, Niklaus Kämpfer, Eliane Maillard Barras, Lorena Moreira, Gerald Nedoluha, Corinne Vigouroux, Thomas Blumenstock, Matthias Schneider, Omaira García, Nicholas Jones, Emmanuel Mahieu, Dan Smale, Michael Kotkamp, John Robinson, Irina Petropavlovskikh, Neil Harris, Birgit Hassler, Daan Hubert, and Fiona Tummon
Atmos. Chem. Phys., 17, 10675–10690, https://doi.org/10.5194/acp-17-10675-2017, https://doi.org/10.5194/acp-17-10675-2017, 2017
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Thanks to the 1987 Montreal Protocol and its amendments, ozone-depleting chlorine (and bromine) in the stratosphere has declined slowly since the late 1990s. Improved and extended long-term ozone profile observations from satellites and ground-based stations confirm that ozone is responding as expected and has increased by about 2 % per decade since 2000 in the upper stratosphere, around 40 km altitude. At lower altitudes, however, ozone has not changed significantly since 2000.
Martin P. Langowski, Christian von Savigny, John P. Burrows, Didier Fussen, Erin C. M. Dawkins, Wuhu Feng, John M. C. Plane, and Daniel R. Marsh
Atmos. Meas. Tech., 10, 2989–3006, https://doi.org/10.5194/amt-10-2989-2017, https://doi.org/10.5194/amt-10-2989-2017, 2017
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Meteoric metals form metal layers in the upper atmosphere anandplay a role in the formation of middle-atmospheric clouds and aerosols. However, the total metal influx rate is not well known. Global Na datasets from measurements and a model are available, which had not been compared yet on a global scale until this paper. Overall the agreement is good, and many differences between measurements are also found in the model simulations. However, the modeled layer altitude is too low.
Jia Jia, Annette Ladstätter-Weißenmayer, Xuewei Hou, Alexei Rozanov, and John P. Burrows
Atmos. Chem. Phys., 17, 4915–4930, https://doi.org/10.5194/acp-17-4915-2017, https://doi.org/10.5194/acp-17-4915-2017, 2017
Stefan Lossow, Farahnaz Khosrawi, Gerald E. Nedoluha, Faiza Azam, Klaus Bramstedt, John. P. Burrows, Bianca M. Dinelli, Patrick Eriksson, Patrick J. Espy, Maya García-Comas, John C. Gille, Michael Kiefer, Stefan Noël, Piera Raspollini, William G. Read, Karen H. Rosenlof, Alexei Rozanov, Christopher E. Sioris, Gabriele P. Stiller, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 10, 1111–1137, https://doi.org/10.5194/amt-10-1111-2017, https://doi.org/10.5194/amt-10-1111-2017, 2017
Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, Chris A. McLinden, Peter F. Bernath, Adam E. Bourassa, John P. Burrows, Doug A. Degenstein, Bernd Funke, Didier Fussen, Gloria L. Manney, C. Thomas McElroy, Donal Murtagh, Cora E. Randall, Piera Raspollini, Alexei Rozanov, James M. Russell III, Makoto Suzuki, Masato Shiotani, Joachim Urban, Thomas von Clarmann, and Joseph M. Zawodny
Atmos. Meas. Tech., 9, 5781–5810, https://doi.org/10.5194/amt-9-5781-2016, https://doi.org/10.5194/amt-9-5781-2016, 2016
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This study validates version 3.5 of the ACE-FTS NOy species data sets by comparing diurnally scaled ACE-FTS data to correlative data from 11 other satellite limb sounders. For all five species examined (NO, NO2, HNO3, N2O5, and ClONO2), there is good agreement between ACE-FTS and the other data sets in various regions of the atmosphere. In these validated regions, these NOy data products can be used for further investigation into the composition, dynamics, and climate of the stratosphere.
Kai-Uwe Eichmann, Luca Lelli, Christian von Savigny, Harjinder Sembhi, and John P. Burrows
Atmos. Meas. Tech., 9, 793–815, https://doi.org/10.5194/amt-9-793-2016, https://doi.org/10.5194/amt-9-793-2016, 2016
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Height-resolved limb radiance spectra of the satellite instrument SCIAMACHY are used to retrieve cloud top heights with a colour index method. Clouds are detectable from the lower to the uppermost troposphere. These cloud heights help to improve the trace gas retrieval for the upper troposphere and lower stratosphere. Comparisons with other data sets have shown good agreement. As clouds and aerosols are not distinguishable, lower stratospheric volcanic aerosol clouds are detected in some years.
M. P. Langowski, C. von Savigny, J. P. Burrows, V. V. Rozanov, T. Dunker, U.-P. Hoppe, M. Sinnhuber, and A. C. Aikin
Atmos. Meas. Tech., 9, 295–311, https://doi.org/10.5194/amt-9-295-2016, https://doi.org/10.5194/amt-9-295-2016, 2016
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An algorithm has been developed for the retrieval of sodium atom (Na) number density on a latitude and altitude grid from SCIAMACHY limb measurements of the Na resonance fluorescence (multiannual means 2008–2012). The Na layer peaks at 90 to 93 km altitude and has a FWHM of 5 to 15 km. A summer minimum in peak density and width is observed at high latitudes. At low latitudes, a semiannual oscillation is found. The results are compared with other measurements and models and agree well with these.
F. Ebojie, J. P. Burrows, C. Gebhardt, A. Ladstätter-Weißenmayer, C. von Savigny, A. Rozanov, M. Weber, and H. Bovensmann
Atmos. Chem. Phys., 16, 417–436, https://doi.org/10.5194/acp-16-417-2016, https://doi.org/10.5194/acp-16-417-2016, 2016
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The goal of this study is to determine the global and zonal changes in the tropospheric ozone data product derived from SCIAMACHY limb-nadir-matching (LNM) observations during the period 2003–2011.
Tropospheric O3 shows statistically significant increases over some regions of South Asia, the South American continent, Alaska, around Congo in Africa and over some continental outflows. Significant decrease in TOC is observed over some continents and oceans.
K. Weigel, A. Rozanov, F. Azam, K. Bramstedt, R. Damadeo, K.-U. Eichmann, C. Gebhardt, D. Hurst, M. Kraemer, S. Lossow, W. Read, N. Spelten, G. P. Stiller, K. A. Walker, M. Weber, H. Bovensmann, and J. P. Burrows
Atmos. Meas. Tech., 9, 133–158, https://doi.org/10.5194/amt-9-133-2016, https://doi.org/10.5194/amt-9-133-2016, 2016
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The SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) aboard the Envisat satellite provided measurements between 2002 and 2012 with different viewing geometries. The limb viewing geometry allows the retrieval of water vapour profiles in the UTLS (upper troposphere and lower stratosphere) from the near-infrared spectral range (1353–1410 nm). Here, we present data version 3.01 and compare it to other water vapour data.
F. Khosrawi, J. Urban, S. Lossow, G. Stiller, K. Weigel, P. Braesicke, M. C. Pitts, A. Rozanov, J. P. Burrows, and D. Murtagh
Atmos. Chem. Phys., 16, 101–121, https://doi.org/10.5194/acp-16-101-2016, https://doi.org/10.5194/acp-16-101-2016, 2016
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Our sensitivity studies based on air parcel trajectories confirm that Polar stratospheric cloud (PSC) formation is quite sensitive to water vapour and temperature changes. Considering water vapour time series from satellite measurements we do not find a consistent, significant trend in water vapour in the lower stratosphere during the past 15 years (2000–2014). Thus, the severe dentrification observed in 2010/2011 cannot be directly related to increases in stratospheric water vapour.
C. von Savigny, F. Ernst, A. Rozanov, R. Hommel, K.-U. Eichmann, V. Rozanov, J. P. Burrows, and L. W. Thomason
Atmos. Meas. Tech., 8, 5223–5235, https://doi.org/10.5194/amt-8-5223-2015, https://doi.org/10.5194/amt-8-5223-2015, 2015
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This article presents validation results for stratospheric aerosol extinction profiles retrieved from limb-scatter measurements with the SCIAMACHY instrument on the Envisat satellite. The SCIAMACHY retrievals are compared to co-located measurements with the SAGE II instrument. Very good agreement to within about 15% is found in a global average sense at altitudes above 15 km. The article also presents sample results on the global morphology of the stratospheric aerosol layer from 2003 to 2011.
N. Rahpoe, M. Weber, A. V. Rozanov, K. Weigel, H. Bovensmann, J. P. Burrows, A. Laeng, G. Stiller, T. von Clarmann, E. Kyrölä, V. F. Sofieva, J. Tamminen, K. Walker, D. Degenstein, A. E. Bourassa, R. Hargreaves, P. Bernath, J. Urban, and D. P. Murtagh
Atmos. Meas. Tech., 8, 4369–4381, https://doi.org/10.5194/amt-8-4369-2015, https://doi.org/10.5194/amt-8-4369-2015, 2015
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The analyses among six satellite instruments measuring ozone reveals that the relative drift between the sensors is not significant in the stratosphere and we conclude that merging of data from these instruments is possible. The merged ozone profiles can then be ingested in global climate models for long-term forecasts of ozone and climate change in the atmosphere. The added drift uncertainty is estimated at about 3% per decade (1 sigma) and should be applied in the calculation of ozone trends.
T. Wagner, S. Beirle, S. Dörner, M. Penning de Vries, J. Remmers, A. Rozanov, and R. Shaiganfar
Atmos. Meas. Tech., 8, 4265–4280, https://doi.org/10.5194/amt-8-4265-2015, https://doi.org/10.5194/amt-8-4265-2015, 2015
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We present a new method for the absolute calibration of atmospheric radiance measurements. Existing methods are based on laboratory measurements, but our method uses the atmospheric radiance measurements themselves. For selected sky conditions these measurements are compared to radiative transfer simulations. The method is very accurate (better than 7%) and might be used for a variety of scientific applications, as well as for the determination of the energy yield of photovoltaic cells.
J. Jia, A. Rozanov, A. Ladstätter-Weißenmayer, and J. P. Burrows
Atmos. Meas. Tech., 8, 3369–3383, https://doi.org/10.5194/amt-8-3369-2015, https://doi.org/10.5194/amt-8-3369-2015, 2015
O. Lednyts'kyy, C. von Savigny, K.-U. Eichmann, and M. G. Mlynczak
Atmos. Meas. Tech., 8, 1021–1041, https://doi.org/10.5194/amt-8-1021-2015, https://doi.org/10.5194/amt-8-1021-2015, 2015
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This paper deals with the retrieval of atomic oxygen concentration profiles in the Earth's upper mesosphere/lower thermosphere region from SCIAMACHY observations of oxygen green line airglow emissions. Atomic oxygen is one of the most important chemical constituents of this atmospheric region, and long-term satellite data sets are rare. The paper includes a detailed description of the retrieval algorithm, an error budget, validation results and some first scientific analyses.
M. P. Langowski, C. von Savigny, J. P. Burrows, W. Feng, J. M. C. Plane, D. R. Marsh, D. Janches, M. Sinnhuber, A. C. Aikin, and P. Liebing
Atmos. Chem. Phys., 15, 273–295, https://doi.org/10.5194/acp-15-273-2015, https://doi.org/10.5194/acp-15-273-2015, 2015
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Global concentration fields of Mg and Mg+ in the Earth's upper mesosphere and lower thermosphere (70-150km) are presented. These are retrieved from SCIAMACHY/Envisat satellite grating spectrometer measurements in limb viewing geometry between 2008 and 2012.
These were compared with WACCM-Mg model results and a large fraction of the available measurement results for these species, and an interpretation of the results is done. The variation of these species during NLC presence is discussed.
J. Aschmann, J. P. Burrows, C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, and A. M. Thompson
Atmos. Chem. Phys., 14, 12803–12814, https://doi.org/10.5194/acp-14-12803-2014, https://doi.org/10.5194/acp-14-12803-2014, 2014
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This study compares observations and simulation results of ozone in the lower tropical stratosphere. It shows that ozone in this region decreased from 1985 up to about 2002, which is consistent with an increase in tropical upwelling predicted by climate models. However, the decrease effectively stops after 2002, indicating that significant changes in tropical upwelling have occurred. The most important factor appears to be that the vertical ascent in the tropics is no longer accelerating.
K. Noguchi, A. Richter, V. Rozanov, A. Rozanov, J. P. Burrows, H. Irie, and K. Kita
Atmos. Meas. Tech., 7, 3497–3508, https://doi.org/10.5194/amt-7-3497-2014, https://doi.org/10.5194/amt-7-3497-2014, 2014
S. Kowalewski, C. von Savigny, M. Palm, I. C. McDade, and J. Notholt
Atmos. Chem. Phys., 14, 10193–10210, https://doi.org/10.5194/acp-14-10193-2014, https://doi.org/10.5194/acp-14-10193-2014, 2014
F. Ebojie, C. von Savigny, A. Ladstätter-Weißenmayer, A. Rozanov, M. Weber, K.-U. Eichmann, S. Bötel, N. Rahpoe, H. Bovensmann, and J. P. Burrows
Atmos. Meas. Tech., 7, 2073–2096, https://doi.org/10.5194/amt-7-2073-2014, https://doi.org/10.5194/amt-7-2073-2014, 2014
B. Hassler, I. Petropavlovskikh, J. Staehelin, T. August, P. K. Bhartia, C. Clerbaux, D. Degenstein, M. De Mazière, B. M. Dinelli, A. Dudhia, G. Dufour, S. M. Frith, L. Froidevaux, S. Godin-Beekmann, J. Granville, N. R. P. Harris, K. Hoppel, D. Hubert, Y. Kasai, M. J. Kurylo, E. Kyrölä, J.-C. Lambert, P. F. Levelt, C. T. McElroy, R. D. McPeters, R. Munro, H. Nakajima, A. Parrish, P. Raspollini, E. E. Remsberg, K. H. Rosenlof, A. Rozanov, T. Sano, Y. Sasano, M. Shiotani, H. G. J. Smit, G. Stiller, J. Tamminen, D. W. Tarasick, J. Urban, R. J. van der A, J. P. Veefkind, C. Vigouroux, T. von Clarmann, C. von Savigny, K. A. Walker, M. Weber, J. Wild, and J. M. Zawodny
Atmos. Meas. Tech., 7, 1395–1427, https://doi.org/10.5194/amt-7-1395-2014, https://doi.org/10.5194/amt-7-1395-2014, 2014
R. Hommel, K.-U. Eichmann, J. Aschmann, K. Bramstedt, M. Weber, C. von Savigny, A. Richter, A. Rozanov, F. Wittrock, F. Khosrawi, R. Bauer, and J. P. Burrows
Atmos. Chem. Phys., 14, 3247–3276, https://doi.org/10.5194/acp-14-3247-2014, https://doi.org/10.5194/acp-14-3247-2014, 2014
C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, H. Bovensmann, J. P. Burrows, D. Degenstein, L. Froidevaux, and A. M. Thompson
Atmos. Chem. Phys., 14, 831–846, https://doi.org/10.5194/acp-14-831-2014, https://doi.org/10.5194/acp-14-831-2014, 2014
M. Langowski, M. Sinnhuber, A. C. Aikin, C. von Savigny, and J. P. Burrows
Atmos. Meas. Tech., 7, 29–48, https://doi.org/10.5194/amt-7-29-2014, https://doi.org/10.5194/amt-7-29-2014, 2014
N. Rahpoe, C. von Savigny, M. Weber, A.V. Rozanov, H. Bovensmann, and J. P. Burrows
Atmos. Meas. Tech., 6, 2825–2837, https://doi.org/10.5194/amt-6-2825-2013, https://doi.org/10.5194/amt-6-2825-2013, 2013
A. Hilboll, A. Richter, A. Rozanov, Ø. Hodnebrog, A. Heckel, S. Solberg, F. Stordal, and J. P. Burrows
Atmos. Meas. Tech., 6, 565–584, https://doi.org/10.5194/amt-6-565-2013, https://doi.org/10.5194/amt-6-565-2013, 2013
Related subject area
Subject: Proxy Use-Development-Validation | Archive: Historical Records | Timescale: Centennial-Decadal
The spatio-temporal evolution of the Chongzhen drought (1627–1644) in China and its impact on famine
Strong volcanic-induced climatic shocks on historical Moselle wine production
Multiproxy tree ring reconstruction of glacier mass balance: insights from Pinus cembra trees growing near Silvretta Glacier (Swiss Alps)
Effects of weather and climate on fluctuations of grain prices in southwestern Bohemia, 1725–1824 CE
Reconstruction of drought and long-rain chronologies since the 17th century in Central Japan using intra-annual tree-ring oxygen isotope ratios and documentary records
Climate and disease in historical urban space: evidence from 19th century Poznań, Poland
Climatic signatures in early modern European grain harvest yields
Pre-industrial temperature variability on the Swiss Plateau derived from the instrumental daily series of Bern and Zurich
Meteorological and climatological triggers of notable past and present bark beetle outbreaks in the Czech Republic
Quantifying and reducing researcher subjectivity in the generation of climate indices from documentary sources
Documentary-based climate reconstructions in the Czech Lands 1501–2020 CE and their European context
Controlling water infrastructure and codifying water knowledge: institutional responses to severe drought in Barcelona (1620–1650)
Reassessing long-term drought risk and societal impacts in Shenyang, Liaoning Province, north-east China (1200–2015)
Climate records in ancient Chinese diaries and their application in historical climate reconstruction – a case study of Yunshan Diary
Reconstructions of droughts in Germany since 1500 – combining hermeneutic information and instrumental records in historical and modern perspectives
A survey of the impact of summer droughts in southern and eastern England, 1200–1700
A 424-year tree-ring-based Palmer Drought Severity Index reconstruction of Cedrus deodara D. Don from the Hindu Kush range of Pakistan: linkages to ocean oscillations
Droughts in the area of Poland in recent centuries in the light of multi-proxy data
Rogation ceremonies: a key to understanding past drought variability in northeastern Spain since 1650
The longest homogeneous series of grape harvest dates, Beaune 1354–2018, and its significance for the understanding of past and present climate
The weather behind words – new methodologies for integrated hydrometeorological reconstruction through documentary sources
Extreme droughts and human responses to them: the Czech Lands in the pre-instrumental period
Documentary data and the study of past droughts: a global state of the art
A 414-year tree-ring-based April–July minimum temperature reconstruction and its implications for the extreme climate events, northeast China
Streamflow variability over the 1881–2011 period in northern Québec: comparison of hydrological reconstructions based on tree rings and geopotential height field reanalysis
Temperature changes derived from phenological and natural evidence in South Central China from 1850 to 2008
Droughts in the Czech Lands, 1090–2012 AD
Temperature changes over the past 2000 yr in China and comparison with the Northern Hemisphere
Multi-periodic climate dynamics: spectral analysis of long-term instrumental and proxy temperature records
An open-access database of grape harvest dates for climate research: data description and quality assessment
Winter temperature variations over the middle and lower reaches of the Yangtze River since 1736 AD
Assessing extreme droughts in Spain during 1750–1850 from rogation ceremonies
Continental atmospheric circulation over Europe during the Little Ice Age inferred from grape harvest dates
Hydrometeorological extremes derived from taxation records for south-eastern Moravia, Czech Republic, 1751–1900 AD
A shift in the spatial pattern of Iberian droughts during the 17th century
Siying Chen, Yun Su, Xudong Chen, and Liang Emlyn Yang
Clim. Past, 20, 2287–2307, https://doi.org/10.5194/cp-20-2287-2024, https://doi.org/10.5194/cp-20-2287-2024, 2024
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This study used 1802 drought and 1977 famine records from historical documents to reconstruct the spatial–temporal progression of the Chongzhen drought (1627–1644) in China and its impacts. We advance this research by reconstructing the annual spatial patterns and regional series of drought; demonstrating drought as the primary factor triggering famine; and identifying the transmission pathway of the drought's impacts and how social factors, especially human responses, regulated these impacts.
Fredrik Charpentier Ljungqvist, Bo Christiansen, Lea Schneider, and Peter Thejll
Clim. Past Discuss., https://doi.org/10.5194/cp-2024-41, https://doi.org/10.5194/cp-2024-41, 2024
Revised manuscript accepted for CP
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We study the climatic signal, with focus on volcanic-induced shocks, in two long annual records of wine production quantity (spanning 1444–1786) from present-day Luxembourg, close to the northern limit of viticulture in Europe. Highly significant wine production declines are found during years following major volcanic events. Furthermore, warmer and drier climate conditions favoured wine production, with spring and summer conditions being the most important ones.
Jérôme Lopez-Saez, Christophe Corona, Lenka Slamova, Matthias Huss, Valérie Daux, Kurt Nicolussi, and Markus Stoffel
Clim. Past, 20, 1251–1267, https://doi.org/10.5194/cp-20-1251-2024, https://doi.org/10.5194/cp-20-1251-2024, 2024
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Glaciers in the European Alps have been retreating since the 1850s. Monitoring glacier mass balance is vital for understanding global changes, but only a few glaciers have long-term data. This study aims to reconstruct the mass balance of the Silvretta Glacier in the Swiss Alps using stable isotopes and tree ring proxies. Results indicate increased glacier mass until the 19th century, followed by a sharp decline after the Little Ice Age with accelerated losses due to anthropogenic warming.
Rudolf Brázdil, Jan Lhoták, Kateřina Chromá, and Petr Dobrovolný
Clim. Past, 20, 1017–1037, https://doi.org/10.5194/cp-20-1017-2024, https://doi.org/10.5194/cp-20-1017-2024, 2024
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The newly developed series of wheat, rye, barley, and oats prices from Sušice (southwestern Bohemia) for the period 1725–1824 CE is used to demonstrate effects of weather, climate, socio-economic, and societal factors on their fluctuations, with particular attention paid to years with extremely high prices. Cold spring temperatures and wet conditions from winter to summer were reflected in very high grain prices.
Hiroto Iizuka, Kenjiro Sho, Zhen Li, Masaki Sano, Yoshikazu Kato, and Takeshi Nakatsuka
EGUsphere, https://doi.org/10.5194/egusphere-2024-627, https://doi.org/10.5194/egusphere-2024-627, 2024
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In general, it is not easy to examine unseasonable weather years that have affected human history using a single proxy. In this study, we propose a new method to quantitatively extract drought/long rainfall events over the past 400 years by integrating tree-ring cellulose oxygen isotope ratios and historical documentary records. The results can be utilized to investigate the relationship between climate and long human history.
Grażyna Liczbińska, Jörg Peter Vögele, and Marek Brabec
Clim. Past, 20, 137–150, https://doi.org/10.5194/cp-20-137-2024, https://doi.org/10.5194/cp-20-137-2024, 2024
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This study examines the relationship between temperature and precipitation as explanatory variables for the probability of death due to waterborne and airborne diseases in historical urban space. The lagged effects of temperature and precipitation on waterborne and airborne diseases were significant, except for the smooth lagged average monthly temperature effect for the latter. There was also significant spatial heterogeneity in the prevalence of deaths due to waterborne and airborne diseases.
Fredrik Charpentier Ljungqvist, Bo Christiansen, Jan Esper, Heli Huhtamaa, Lotta Leijonhufvud, Christian Pfister, Andrea Seim, Martin Karl Skoglund, and Peter Thejll
Clim. Past, 19, 2463–2491, https://doi.org/10.5194/cp-19-2463-2023, https://doi.org/10.5194/cp-19-2463-2023, 2023
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We study the climate signal in long harvest series from across Europe between the 16th and 18th centuries. The climate–harvest yield relationship is found to be relatively weak but regionally consistent and similar in strength and sign to modern climate–harvest yield relationships. The strongest climate–harvest yield patterns are a significant summer soil moisture signal in Sweden, a winter temperature and precipitation signal in Switzerland, and spring temperature signals in Spain.
Yuri Brugnara, Chantal Hari, Lucas Pfister, Veronika Valler, and Stefan Brönnimann
Clim. Past, 18, 2357–2379, https://doi.org/10.5194/cp-18-2357-2022, https://doi.org/10.5194/cp-18-2357-2022, 2022
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We digitized dozens of weather journals containing temperature measurements from in and around Bern and Zurich. They cover over a century before the creation of a national weather service in Switzerland. With these data we could create daily temperature series for the two cities that span the last 265 years. We found that the pre-industrial climate on the Swiss Plateau was colder than suggested by previously available instrumental data sets and about 2.5 °C colder than the present-day climate.
Rudolf Brázdil, Petr Zahradník, Péter Szabó, Kateřina Chromá, Petr Dobrovolný, Lukáš Dolák, Miroslav Trnka, Jan Řehoř, and Silvie Suchánková
Clim. Past, 18, 2155–2180, https://doi.org/10.5194/cp-18-2155-2022, https://doi.org/10.5194/cp-18-2155-2022, 2022
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Bark beetle outbreaks are important disturbances to Norway spruce forests. Their meteorological and climatological triggers are analysed for the main oubreaks over the territory of the Czech Republic based on newly created series of such outbreaks, covering the 1781–2021 CE period. The paper demonstrates the shift from windstorms as the main meteorological triggers of past outbreaks to effects of high temperatures and droughts together with windstorms in past decades.
George C. D. Adamson, David J. Nash, and Stefan W. Grab
Clim. Past, 18, 1071–1081, https://doi.org/10.5194/cp-18-1071-2022, https://doi.org/10.5194/cp-18-1071-2022, 2022
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Descriptions of climate held in archives are a valuable source of past climate variability, but there is a large potential for error in assigning quantitative indices (e.g. −2, v. dry to +2, v. wet) to descriptive data. This is the first study to examine this uncertainty. We gave the same dataset to 71 postgraduate students and 6 professional scientists, findings that error can be minimized by taking an average of indices developed by eight postgraduates and only two professional climatologists.
Rudolf Brázdil, Petr Dobrovolný, Jiří Mikšovský, Petr Pišoft, Miroslav Trnka, Martin Možný, and Jan Balek
Clim. Past, 18, 935–959, https://doi.org/10.5194/cp-18-935-2022, https://doi.org/10.5194/cp-18-935-2022, 2022
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The paper deals with 520-year series (1501–2020 CE) of temperature, precipitation, and four drought indices reconstructed from documentary evidence and instrumental observations for the Czech Lands. Basic features of their fluctuations, long-term trends, and periodicities as well as attribution to changes in external forcings and climate variability modes are analysed. Representativeness of Czech reconstructions at European scale is evaluated. The paper shows extreme character of past decades.
Santiago Gorostiza, Maria Antònia Martí Escayol, and Mariano Barriendos
Clim. Past, 17, 913–927, https://doi.org/10.5194/cp-17-913-2021, https://doi.org/10.5194/cp-17-913-2021, 2021
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How did cities respond to drought during the 17th century? This article studies the strategies followed by the city government of Barcelona during the severely dry period from 1620 to 1650. Beyond the efforts to expand urban water supply sources and to improve the maintenance of the system, the city government decided to compile knowledge about water infrastructure into a book and to restrict access to it. This management strategy aimed to increase the city's control over water.
LingYun Tang, Neil Macdonald, Heather Sangster, Richard Chiverrell, and Rachel Gaulton
Clim. Past, 16, 1917–1935, https://doi.org/10.5194/cp-16-1917-2020, https://doi.org/10.5194/cp-16-1917-2020, 2020
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A historical drought series (since 1200 CE) for Shenyang, NE China, shows 20th century droughts comparable in magnitude to recent severe droughts. Drought resilience driven by early 20th century societal/cultural changes reduced loss of life compared with the 1887 and 1891 droughts. A longer temporal analysis from integrated precipitation and historical records shows an earlier onset to droughts. Regional standardised precipitation indices could provide early warnings for drought development.
Siying Chen, Yun Su, Xiuqi Fang, and Jia He
Clim. Past, 16, 1873–1887, https://doi.org/10.5194/cp-16-1873-2020, https://doi.org/10.5194/cp-16-1873-2020, 2020
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Private diaries are important sources of historical data for research on climate change. Through a case study of Yunshan Diary, authored by Bi Guo of the Yuan dynasty of China, this article demonstrates how to delve into climate information in ancient diaries, mainly including species distribution records, phenological records and daily weather descriptions. This article considers how to use these records to reconstruct climate change and extreme climatic events on various timescales.
Rüdiger Glaser and Michael Kahle
Clim. Past, 16, 1207–1222, https://doi.org/10.5194/cp-16-1207-2020, https://doi.org/10.5194/cp-16-1207-2020, 2020
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A new study on droughts in Germany since 1500 reveals the long-term trend of single extreme events, as well as drier periods. Extreme droughts appeared in 1540, 1590, 1615, 1706, 1834, 1893, 1921, 1949 and 2018. Like today, droughts had manifold impacts such as harvest failures, water deficits, low water levels and forest fires. This had different societal consequences ranging from famine, disease, rising prices, migration and riots leading to subsidies and discussions on climate change.
Kathleen Pribyl
Clim. Past, 16, 1027–1041, https://doi.org/10.5194/cp-16-1027-2020, https://doi.org/10.5194/cp-16-1027-2020, 2020
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Droughts pose a climatic hazard that can have a profound impacts on past societies. Using documentary sources, this paper studies the occurrence and impacts of spring–summer droughts in pre-industrial England from 1200 to 1700. The impacts most relevant to human livelihood, including the agricultural and pastoral sectors of agrarian production, and public health are evaluated.
Sarir Ahmad, Liangjun Zhu, Sumaira Yasmeen, Yuandong Zhang, Zongshan Li, Sami Ullah, Shijie Han, and Xiaochun Wang
Clim. Past, 16, 783–798, https://doi.org/10.5194/cp-16-783-2020, https://doi.org/10.5194/cp-16-783-2020, 2020
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This study provides the opportunity to extend climatic records to preindustrial periods in northern Pakistan. The reconstructed March–August PDSIs for the past 424 years, going back to 1593 CE, enable scientists to know how these areas were prone to climatic extremes in the past. The instrumental data are limited in Pakistan; however, the Cedrus deodara tree that preserves physical characteristics of past climatic variabilities can provide insight into the trend of climatic changes.
Rajmund Przybylak, Piotr Oliński, Marcin Koprowski, Janusz Filipiak, Aleksandra Pospieszyńska, Waldemar Chorążyczewski, Radosław Puchałka, and Henryk Paweł Dąbrowski
Clim. Past, 16, 627–661, https://doi.org/10.5194/cp-16-627-2020, https://doi.org/10.5194/cp-16-627-2020, 2020
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The paper presents the main features of droughts in Poland in the period 996–2015 based on proxy data (documentary and dendrochronological) and instrumental measurements of precipitation. More than 100 droughts were found in documentary sources from the mid-15th century to the end of the 18th century with a maximum in the second halves of the 17th and, particularly, the 18th century. The long-term frequency of droughts in Poland has been stable for the last two or three centuries.
Ernesto Tejedor, Martín de Luis, Mariano Barriendos, José María Cuadrat, Jürg Luterbacher, and Miguel Ángel Saz
Clim. Past, 15, 1647–1664, https://doi.org/10.5194/cp-15-1647-2019, https://doi.org/10.5194/cp-15-1647-2019, 2019
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We developed a new dataset of historical documents by compiling records (rogation ceremonies) from 13 cities in the northeast of the Iberian Peninsula (IP). These records were transformed into quantitative continuous data to develop drought indices (DIs). We regionalized them by creating three DIs (Ebro Valle, Mediterranean, and Mountain), which cover the period from 1650 to 1899 CE. We identified extreme drought years and periods which help to understand climate variability in the IP.
Thomas Labbé, Christian Pfister, Stefan Brönnimann, Daniel Rousseau, Jörg Franke, and Benjamin Bois
Clim. Past, 15, 1485–1501, https://doi.org/10.5194/cp-15-1485-2019, https://doi.org/10.5194/cp-15-1485-2019, 2019
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In this paper we present the longest grape harvest date (GHD) record reconstructed to date, i.e. Beaune (France, Burgundy) 1354–2018. Drawing on unedited archive material, the series is validated using the long Paris temperature series that goes back to 1658 and was used to assess April-to-July temperatures from 1354 to 2018. The distribution of extremely early GHD is uneven over the 664-year-long period of the series and mirrors the rapid global warming from 1988 to 2018.
Salvador Gil-Guirado, Juan José Gómez-Navarro, and Juan Pedro Montávez
Clim. Past, 15, 1303–1325, https://doi.org/10.5194/cp-15-1303-2019, https://doi.org/10.5194/cp-15-1303-2019, 2019
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The historical climatology has remarkable research potentialities. However, historical climatology has some methodological limitations. This study presents a new methodology (COST) that allows us to perform climate reconstructions with monthly resolution. The variability of the climatic series obtained are coherent with previous studies. The new proposed method is objective and is not affected by social changes, which allows us to perform studies in regions with different languages and cultures.
Rudolf Brázdil, Petr Dobrovolný, Miroslav Trnka, Ladislava Řezníčková, Lukáš Dolák, and Oldřich Kotyza
Clim. Past, 15, 1–24, https://doi.org/10.5194/cp-15-1-2019, https://doi.org/10.5194/cp-15-1-2019, 2019
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The paper analyses extreme droughts of the pre-instrumental period (1501–1803) over the territory of the recent Czech Republic. In total, 16 droughts were selected for spring, summer and autumn each and 14 droughts for summer half-year (Apr–Sep). They are characterized by very low values of drought indices, high temperatures, low precipitation and by the influence of high-pressure situations. Selected extreme droughts are described in more detail. Effect of droughts on grain prices are studied.
Rudolf Brázdil, Andrea Kiss, Jürg Luterbacher, David J. Nash, and Ladislava Řezníčková
Clim. Past, 14, 1915–1960, https://doi.org/10.5194/cp-14-1915-2018, https://doi.org/10.5194/cp-14-1915-2018, 2018
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The paper presents a worldwide state of the art of droughts fluctuations based on documentary data. It gives an overview of achievements related to different kinds of documentary evidence with their examples and an overview of papers presenting long-term drought chronologies over the individual continents, analysis of the most outstanding drought events, the influence of external forcing and large-scale climate drivers, and human impacts and responses. It recommends future research directions.
Shanna Lyu, Zongshan Li, Yuandong Zhang, and Xiaochun Wang
Clim. Past, 12, 1879–1888, https://doi.org/10.5194/cp-12-1879-2016, https://doi.org/10.5194/cp-12-1879-2016, 2016
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This study presents a 414-year growing season minimum temperature reconstruction based on Korean pine tree-ring series at Laobai Mountain, northeast China. It developed a more than 400-year climate record in this area for the first time. This reconstruction showed six cold periods, seven warm periods, and natural disaster records of extreme climate events.
Pierre Brigode, François Brissette, Antoine Nicault, Luc Perreault, Anna Kuentz, Thibault Mathevet, and Joël Gailhard
Clim. Past, 12, 1785–1804, https://doi.org/10.5194/cp-12-1785-2016, https://doi.org/10.5194/cp-12-1785-2016, 2016
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In this paper, we apply a new hydro-climatic reconstruction method on the Caniapiscau Reservoir (Canada), compare the obtained streamflow time series against time series derived from dendrohydrology by other authors on the same catchment, and study the natural streamflow variability over the 1881–2011 period. This new reconstruction is based on a historical reanalysis of global geopotential height fields and aims to produce daily streamflow time series (using a rainfall–runoff model).
J. Zheng, Z. Hua, Y. Liu, and Z. Hao
Clim. Past, 11, 1553–1561, https://doi.org/10.5194/cp-11-1553-2015, https://doi.org/10.5194/cp-11-1553-2015, 2015
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In this paper we reconstruct the annual temperature anomalies in South Central China from 1850 to 2008, using phenodates of plants, snowfall days, and five tree-ring width chronologies. It is found that rapid warming has occurred since the 1990s, with an abrupt change around 1997, leading to unprecedented variability in warming; a cold interval dominated the 1860s, 1890s, and 1950s; warm decades occurred around 1850, 1870, and 1960; and the warmest decades were the 1990s–2000s.
R. Brázdil, P. Dobrovolný, M. Trnka, O. Kotyza, L. Řezníčková, H. Valášek, P. Zahradníček, and P. Štěpánek
Clim. Past, 9, 1985–2002, https://doi.org/10.5194/cp-9-1985-2013, https://doi.org/10.5194/cp-9-1985-2013, 2013
Q. Ge, Z. Hao, J. Zheng, and X. Shao
Clim. Past, 9, 1153–1160, https://doi.org/10.5194/cp-9-1153-2013, https://doi.org/10.5194/cp-9-1153-2013, 2013
H.-J. Lüdecke, A. Hempelmann, and C. O. Weiss
Clim. Past, 9, 447–452, https://doi.org/10.5194/cp-9-447-2013, https://doi.org/10.5194/cp-9-447-2013, 2013
V. Daux, I. Garcia de Cortazar-Atauri, P. Yiou, I. Chuine, E. Garnier, E. Le Roy Ladurie, O. Mestre, and J. Tardaguila
Clim. Past, 8, 1403–1418, https://doi.org/10.5194/cp-8-1403-2012, https://doi.org/10.5194/cp-8-1403-2012, 2012
Z.-X. Hao, J.-Y. Zheng, Q.-S. Ge, and W.-C. Wang
Clim. Past, 8, 1023–1030, https://doi.org/10.5194/cp-8-1023-2012, https://doi.org/10.5194/cp-8-1023-2012, 2012
F. Domínguez-Castro, P. Ribera, R. García-Herrera, J. M. Vaquero, M. Barriendos, J. M. Cuadrat, and J. M. Moreno
Clim. Past, 8, 705–722, https://doi.org/10.5194/cp-8-705-2012, https://doi.org/10.5194/cp-8-705-2012, 2012
P. Yiou, I. García de Cortázar-Atauri, I. Chuine, V. Daux, E. Garnier, N. Viovy, C. van Leeuwen, A. K. Parker, and J.-M. Boursiquot
Clim. Past, 8, 577–588, https://doi.org/10.5194/cp-8-577-2012, https://doi.org/10.5194/cp-8-577-2012, 2012
R. Brázdil, K. Chromá, H. Valášek, and L. Dolák
Clim. Past, 8, 467–481, https://doi.org/10.5194/cp-8-467-2012, https://doi.org/10.5194/cp-8-467-2012, 2012
F. Domínguez-Castro, R. García-Herrera, P. Ribera, and M. Barriendos
Clim. Past, 6, 553–563, https://doi.org/10.5194/cp-6-553-2010, https://doi.org/10.5194/cp-6-553-2010, 2010
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Co-editor-in-chief
Although previous studies addressed this original way of how deducing past climate conditions from color paintings, such as aerosol optical depth (AOD) the new results are critically reviewing these former publications and yield new critical elements in this original research. While concluding that reconstructions of AOD may be possible in some specific cases, the authors do warn about the strong uncertainties related to parameters not carefully considered, which restrains the field of possibilities. To assess the scientific soundness of the results, three reviewers from complementary fields of atmospheric sciences positively reviewed the original manuscript. They have contributed to improve the quality of this paper and all agreed upon the conclusions research, which is a fair guarantee that these results should broadly interest the geoscience community.
Although previous studies addressed this original way of how deducing past climate conditions...
Short summary
This study investigates the possibility of inferring information on aerosol optical depth from photographs of historic paintings. The idea – which has been applied in previous studies – is very interesting because it would provide an archive of the atmospheric aerosol loading covering many centuries. We show that twilight colours depend not only on the aerosol optical thickness, but also on several other parameters, making a quantitative estimate of aerosol optical depth very difficult.
This study investigates the possibility of inferring information on aerosol optical depth from...
