Articles | Volume 10, issue 1
https://doi.org/10.5194/cp-10-1-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/cp-10-1-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Evaluating climate field reconstruction techniques using improved emulations of real-world conditions
J. Wang
University of Southern California, Los Angeles, California, USA
J. Emile-Geay
University of Southern California, Los Angeles, California, USA
D. Guillot
Stanford University, Stanford, California, USA
J. E. Smerdon
Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
B. Rajaratnam
Stanford University, Stanford, California, USA
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Feng Zhu, Julien Emile-Geay, Gregory J. Hakim, Dominique Guillot, Deborah Khider, Robert Tardif, and Walter A. Perkins
Geosci. Model Dev., 17, 3409–3431, https://doi.org/10.5194/gmd-17-3409-2024, https://doi.org/10.5194/gmd-17-3409-2024, 2024
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Climate field reconstruction encompasses methods that estimate the evolution of climate in space and time based on natural archives. It is useful to investigate climate variations and validate climate models, but its implementation and use can be difficult for non-experts. This paper introduces a user-friendly Python package called cfr to make these methods more accessible, thanks to the computational and visualization tools that facilitate efficient and reproducible research on past climates.
Pedro José Roldán-Gómez, Jesús Fidel González-Rouco, Jason E. Smerdon, and Félix García-Pereira
Clim. Past, 19, 2361–2387, https://doi.org/10.5194/cp-19-2361-2023, https://doi.org/10.5194/cp-19-2361-2023, 2023
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Analyses of reconstructed data suggest that the precipitation and availability of water have evolved in a similar way during the Last Millennium in different regions of the world, including areas of North America, Europe, the Middle East, southern Asia, northern South America, East Africa and the Indo-Pacific. To confirm this link between distant regions and to understand the reasons behind it, the information from different reconstructed and simulated products has been compiled and analyzed.
Rachel M. Walter, Hussein R. Sayani, Thomas Felis, Kim M. Cobb, Nerilie J. Abram, Ariella K. Arzey, Alyssa R. Atwood, Logan D. Brenner, Émilie P. Dassié, Kristine L. DeLong, Bethany Ellis, Julien Emile-Geay, Matthew J. Fischer, Nathalie F. Goodkin, Jessica A. Hargreaves, K. Halimeda Kilbourne, Hedwig Krawczyk, Nicholas P. McKay, Andrea L. Moore, Sujata A. Murty, Maria Rosabelle Ong, Riovie D. Ramos, Emma V. Reed, Dhrubajyoti Samanta, Sara C. Sanchez, Jens Zinke, and the PAGES CoralHydro2k Project Members
Earth Syst. Sci. Data, 15, 2081–2116, https://doi.org/10.5194/essd-15-2081-2023, https://doi.org/10.5194/essd-15-2081-2023, 2023
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Accurately quantifying how the global hydrological cycle will change in the future remains challenging due to the limited availability of historical climate data from the tropics. Here we present the CoralHydro2k database – a new compilation of peer-reviewed coral-based climate records from the last 2000 years. This paper details the records included in the database and where the database can be accessed and demonstrates how the database can investigate past tropical climate variability.
Rebecca Orrison, Mathias Vuille, Jason E. Smerdon, James Apaéstegui, Vitor Azevedo, Jose Leandro P. S. Campos, Francisco W. Cruz, Marcela Eduarda Della Libera, and Nicolás M. Stríkis
Clim. Past, 18, 2045–2062, https://doi.org/10.5194/cp-18-2045-2022, https://doi.org/10.5194/cp-18-2045-2022, 2022
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We evaluated the South American Summer Monsoon over the last millennium and dynamically interpreted the principal modes of variability. We find the spatial patterns of the monsoon are an intrinsic feature of the climate modulated by external forcings. Multi-centennial mean state departures during the Medieval Climate Anomaly and Little Ice Age show regionally coherent patterns of hydroclimatic change in both a multi-archive network of oxygen isotope records and isotope-enabled climate models.
Sooin Yun, Jason E. Smerdon, Bo Li, and Xianyang Zhang
Clim. Past, 17, 2583–2605, https://doi.org/10.5194/cp-17-2583-2021, https://doi.org/10.5194/cp-17-2583-2021, 2021
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Climate field reconstructions (CFRs) estimate spatiotemporal climate conditions hundreds to thousands of years into the past. Assessing CFR skills is critical for improving their interpretation and ultimately for deriving better CFR estimates. We apply new methods for assessing spatiotemporal skill using formalized null hypotheses to derive a detailed assessment of why CFR skill varies across multiple methods, with implications for improving future CFR estimates.
Nicholas P. McKay, Julien Emile-Geay, and Deborah Khider
Geochronology, 3, 149–169, https://doi.org/10.5194/gchron-3-149-2021, https://doi.org/10.5194/gchron-3-149-2021, 2021
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This paper describes geoChronR, an R package that streamlines the process of quantifying age uncertainties, propagating uncertainties through several common analyses, and visualizing the results. In addition to describing the structure and underlying theory of the package, we present five real-world use cases that illustrate common workflows in geoChronR. geoChronR is built on the Linked PaleoData framework, is open and extensible, and we welcome feedback and contributions from the community.
Chris M. Brierley, Anni Zhao, Sandy P. Harrison, Pascale Braconnot, Charles J. R. Williams, David J. R. Thornalley, Xiaoxu Shi, Jean-Yves Peterschmitt, Rumi Ohgaito, Darrell S. Kaufman, Masa Kageyama, Julia C. Hargreaves, Michael P. Erb, Julien Emile-Geay, Roberta D'Agostino, Deepak Chandan, Matthieu Carré, Partrick J. Bartlein, Weipeng Zheng, Zhongshi Zhang, Qiong Zhang, Hu Yang, Evgeny M. Volodin, Robert A. Tomas, Cody Routson, W. Richard Peltier, Bette Otto-Bliesner, Polina A. Morozova, Nicholas P. McKay, Gerrit Lohmann, Allegra N. Legrande, Chuncheng Guo, Jian Cao, Esther Brady, James D. Annan, and Ayako Abe-Ouchi
Clim. Past, 16, 1847–1872, https://doi.org/10.5194/cp-16-1847-2020, https://doi.org/10.5194/cp-16-1847-2020, 2020
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This paper provides an initial exploration and comparison to climate reconstructions of the new climate model simulations of the mid-Holocene (6000 years ago). These use state-of-the-art models developed for CMIP6 and apply the same experimental set-up. The models capture several key aspects of the climate, but some persistent issues remain.
Pedro José Roldán-Gómez, Jesús Fidel González-Rouco, Camilo Melo-Aguilar, and Jason E. Smerdon
Clim. Past, 16, 1285–1307, https://doi.org/10.5194/cp-16-1285-2020, https://doi.org/10.5194/cp-16-1285-2020, 2020
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This work analyses the behavior of atmospheric dynamics and hydroclimate in climate simulations of the last millennium. In particular, how external forcing factors, like solar and volcanic activity and greenhouse gas emissions, impact variables like temperature, pressure, wind, precipitation, and soil moisture is assessed. The results of these analyses show that changes in the forcing could alter the zonal circulation and the intensity and distribution of monsoons and convergence zones.
Robert Tardif, Gregory J. Hakim, Walter A. Perkins, Kaleb A. Horlick, Michael P. Erb, Julien Emile-Geay, David M. Anderson, Eric J. Steig, and David Noone
Clim. Past, 15, 1251–1273, https://doi.org/10.5194/cp-15-1251-2019, https://doi.org/10.5194/cp-15-1251-2019, 2019
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An updated Last Millennium Reanalysis is presented, using an expanded multi-proxy database, and proxy models representing the seasonal characteristics of proxy records, in addition to the dual sensitivity to temperature and moisture of tree-ring-width chronologies. We show enhanced skill in spatial reconstructions of key climate variables in the updated reanalysis, compared to an earlier version, resulting from the combined influences of the enhanced proxy network and improved proxy modeling.
Hansi K. A. Singh, Gregory J. Hakim, Robert Tardif, Julien Emile-Geay, and David C. Noone
Clim. Past, 14, 157–174, https://doi.org/10.5194/cp-14-157-2018, https://doi.org/10.5194/cp-14-157-2018, 2018
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The Atlantic Multidecadal Oscillation (AMO) is prominent in the climate system. We study the AMO over the last 2000 years using a novel proxy framework, the Last Millennium Reanalysis. We find that the AMO is linked to continental warming, Arctic sea ice retreat, and an Atlantic precipitation shift. Low clouds decrease globally. We find no distinct multidecadal spectral peak in the AMO over the last 2 millennia, suggesting that human activities may have enhanced the AMO in the modern era.
PAGES Hydro2k Consortium
Clim. Past, 13, 1851–1900, https://doi.org/10.5194/cp-13-1851-2017, https://doi.org/10.5194/cp-13-1851-2017, 2017
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Water availability is fundamental to societies and ecosystems, but our understanding of variations in hydroclimate (including extreme events, flooding, and decadal periods of drought) is limited due to a paucity of modern instrumental observations. We review how proxy records of past climate and climate model simulations can be used in tandem to understand hydroclimate variability over the last 2000 years and how these tools can also inform risk assessments of future hydroclimatic extremes.
Johann H. Jungclaus, Edouard Bard, Mélanie Baroni, Pascale Braconnot, Jian Cao, Louise P. Chini, Tania Egorova, Michael Evans, J. Fidel González-Rouco, Hugues Goosse, George C. Hurtt, Fortunat Joos, Jed O. Kaplan, Myriam Khodri, Kees Klein Goldewijk, Natalie Krivova, Allegra N. LeGrande, Stephan J. Lorenz, Jürg Luterbacher, Wenmin Man, Amanda C. Maycock, Malte Meinshausen, Anders Moberg, Raimund Muscheler, Christoph Nehrbass-Ahles, Bette I. Otto-Bliesner, Steven J. Phipps, Julia Pongratz, Eugene Rozanov, Gavin A. Schmidt, Hauke Schmidt, Werner Schmutz, Andrew Schurer, Alexander I. Shapiro, Michael Sigl, Jason E. Smerdon, Sami K. Solanki, Claudia Timmreck, Matthew Toohey, Ilya G. Usoskin, Sebastian Wagner, Chi-Ju Wu, Kok Leng Yeo, Davide Zanchettin, Qiong Zhang, and Eduardo Zorita
Geosci. Model Dev., 10, 4005–4033, https://doi.org/10.5194/gmd-10-4005-2017, https://doi.org/10.5194/gmd-10-4005-2017, 2017
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Climate model simulations covering the last millennium provide context for the evolution of the modern climate and for the expected changes during the coming centuries. They can help identify plausible mechanisms underlying palaeoclimatic reconstructions. Here, we describe the forcing boundary conditions and the experimental protocol for simulations covering the pre-industrial millennium. We describe the PMIP4 past1000 simulations as contributions to CMIP6 and additional sensitivity experiments.
Nathan J. Steiger and Jason E. Smerdon
Clim. Past, 13, 1435–1449, https://doi.org/10.5194/cp-13-1435-2017, https://doi.org/10.5194/cp-13-1435-2017, 2017
Nicholas P. McKay and Julien Emile-Geay
Clim. Past, 12, 1093–1100, https://doi.org/10.5194/cp-12-1093-2016, https://doi.org/10.5194/cp-12-1093-2016, 2016
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The lack of accepted data formats and data standards in paleoclimatology is a growing problem that slows progress in the field. Here, we propose a preliminary data standard for paleoclimate data, general enough to accommodate all the proxy and measurement types encountered in a large international collaboration (PAGES 2k). We also introduce a data format for such structured data (Linked Paleo Data, or LiPD), leveraging recent advances in knowledge representation (Linked Open Data).
J. Emile-Geay and M. Tingley
Clim. Past, 12, 31–50, https://doi.org/10.5194/cp-12-31-2016, https://doi.org/10.5194/cp-12-31-2016, 2016
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Ignoring nonlinearity in palaeoclimate records (e.g. continental run-off proxies) runs the risk of severely overstating changes in climate variability. Even with the correct model and parameters, some information is irretrievably lost by such proxies. However, we find that a simple empirical transform can do much to improve the situation, and makes them amenable to classical analyses. Doing so on two palaeo-ENSO records markedly changes some of the quantitative inferences made from such records.
H. Beltrami, G. S. Matharoo, L. Tarasov, V. Rath, and J. E. Smerdon
Clim. Past, 10, 1693–1706, https://doi.org/10.5194/cp-10-1693-2014, https://doi.org/10.5194/cp-10-1693-2014, 2014
M. Comboul, J. Emile-Geay, M. N. Evans, N. Mirnateghi, K. M. Cobb, and D. M. Thompson
Clim. Past, 10, 825–841, https://doi.org/10.5194/cp-10-825-2014, https://doi.org/10.5194/cp-10-825-2014, 2014
Related subject area
Subject: Atmospheric Dynamics | Archive: Terrestrial Archives | Timescale: Centennial-Decadal
South American Summer Monsoon variability over the last millennium in paleoclimate records and isotope-enabled climate models
Long-term global ground heat flux and continental heat storage from geothermal data
Past African dust inputs in the western Mediterranean area controlled by the complex interaction between the Intertropical Convergence Zone, the North Atlantic Oscillation, and total solar irradiance
Two types of North American droughts related to different atmospheric circulation patterns
Centennial-scale precipitation anomalies in the southern Altiplano (18° S) suggest an extratropical driver for the South American summer monsoon during the late Holocene
Early summer hydroclimatic signals are captured well by tree-ring earlywood width in the eastern Qinling Mountains, central China
A millennial summer temperature reconstruction for northeastern Canada using oxygen isotopes in subfossil trees
Variability of summer humidity during the past 800 years on the eastern Tibetan Plateau inferred from δ18O of tree-ring cellulose
The global monsoon across timescales: coherent variability of regional monsoons
Persistent decadal-scale rainfall variability in the tropical South Pacific Convergence Zone through the past six centuries
Climate patterns in north central China during the last 1800 yr and their possible driving force
The reconstruction of easterly wind directions for the Eifel region (Central Europe) during the period 40.3–12.9 ka BP
Rebecca Orrison, Mathias Vuille, Jason E. Smerdon, James Apaéstegui, Vitor Azevedo, Jose Leandro P. S. Campos, Francisco W. Cruz, Marcela Eduarda Della Libera, and Nicolás M. Stríkis
Clim. Past, 18, 2045–2062, https://doi.org/10.5194/cp-18-2045-2022, https://doi.org/10.5194/cp-18-2045-2022, 2022
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We evaluated the South American Summer Monsoon over the last millennium and dynamically interpreted the principal modes of variability. We find the spatial patterns of the monsoon are an intrinsic feature of the climate modulated by external forcings. Multi-centennial mean state departures during the Medieval Climate Anomaly and Little Ice Age show regionally coherent patterns of hydroclimatic change in both a multi-archive network of oxygen isotope records and isotope-enabled climate models.
Francisco José Cuesta-Valero, Almudena García-García, Hugo Beltrami, J. Fidel González-Rouco, and Elena García-Bustamante
Clim. Past, 17, 451–468, https://doi.org/10.5194/cp-17-451-2021, https://doi.org/10.5194/cp-17-451-2021, 2021
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We provide new global estimates of changes in surface temperature, surface heat flux, and continental heat storage since preindustrial times from geothermal data. Our analysis includes new measurements and a more comprehensive description of uncertainties than previous studies. Results show higher continental heat storage than previously reported, with global land mean temperature changes of 1 K and subsurface heat gains of 12 ZJ during the last half of the 20th century.
Pierre Sabatier, Marie Nicolle, Christine Piot, Christophe Colin, Maxime Debret, Didier Swingedouw, Yves Perrette, Marie-Charlotte Bellingery, Benjamin Chazeau, Anne-Lise Develle, Maxime Leblanc, Charlotte Skonieczny, Yoann Copard, Jean-Louis Reyss, Emmanuel Malet, Isabelle Jouffroy-Bapicot, Maëlle Kelner, Jérôme Poulenard, Julien Didier, Fabien Arnaud, and Boris Vannière
Clim. Past, 16, 283–298, https://doi.org/10.5194/cp-16-283-2020, https://doi.org/10.5194/cp-16-283-2020, 2020
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High-resolution multiproxy analysis of sediment core from a high-elevation lake on Corsica allows us to reconstruct past African dust inputs to the western Mediterranean area over the last 3 millennia. Millennial variations of Saharan dust input have been correlated with the long-term southward migration of the Intertropical Convergence Zone, while short-term variations were associated with the North Atlantic Oscillation and total solar irradiance after and before 1070 cal BP, respectively.
Angela-Maria Burgdorf, Stefan Brönnimann, and Jörg Franke
Clim. Past, 15, 2053–2065, https://doi.org/10.5194/cp-15-2053-2019, https://doi.org/10.5194/cp-15-2053-2019, 2019
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The western USA is frequently affected by multiannual summer droughts. They can be separated into two groups with distinct spatial patterns. This study analyzes the atmospheric circulation during multiannual droughts in a new 3-D climate reconstruction. We confirm two distinct drought types differing with respect to atmospheric circulation as well as sea surface temperatures. Our results suggest that both the Pacific and the extratropical North Atlantic region affect North American droughts.
Ignacio A. Jara, Antonio Maldonado, Leticia González, Armand Hernández, Alberto Sáez, Santiago Giralt, Roberto Bao, and Blas Valero-Garcés
Clim. Past, 15, 1845–1859, https://doi.org/10.5194/cp-15-1845-2019, https://doi.org/10.5194/cp-15-1845-2019, 2019
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The South American summer monsoon (SASM) is the most important climate system of South America. However, little is known about its long-term variability. Here we present a new SASM reconstruction from Lago Chungará in the southern Altiplano (18°S). We show important changes in SASM precipitation at timescales of centuries. Our results suggest that SASM variability was controlled not only by tropical climates but was also influenced by precipitation outside the tropics.
Yesi Zhao, Jiangfeng Shi, Shiyuan Shi, Xiaoqi Ma, Weijie Zhang, Bowen Wang, Xuguang Sun, Huayu Lu, and Achim Bräuning
Clim. Past, 15, 1113–1131, https://doi.org/10.5194/cp-15-1113-2019, https://doi.org/10.5194/cp-15-1113-2019, 2019
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We found that the tree-ring earlywood width (EWW) of Pinus tabuliformis from the eastern Qinling Mountains (central China) showed stronger response to May–July scPDSI than the tree-ring total width and latewood width. Therefore, variations in May–July scPDSI were reconstructed back to 1868 CE using the EWW chronology. The reconstruction exhibited a strong in-phase relationship with the East Asian summer monsoon intensity before the 1940s, which was different from that found in recent decades.
M. Naulier, M. M. Savard, C. Bégin, F. Gennaretti, D. Arseneault, J. Marion, A. Nicault, and Y. Bégin
Clim. Past, 11, 1153–1164, https://doi.org/10.5194/cp-11-1153-2015, https://doi.org/10.5194/cp-11-1153-2015, 2015
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This paper presents a millennial δ18O series and the reconstruction of the maximal temperature. The maximal replication and annual resolution have been obtained by using cohort sampling method. Three contrasted climatic periods have been identified: the medieval warm period (~997-1250; the warmest), the little ice age (~1450-1880) and the modern period (1970-2000) that is one of the fastest warming over the last millennium.
J. Wernicke, J. Grießinger, P. Hochreuther, and A. Bräuning
Clim. Past, 11, 327–337, https://doi.org/10.5194/cp-11-327-2015, https://doi.org/10.5194/cp-11-327-2015, 2015
P. X. Wang, B. Wang, H. Cheng, J. Fasullo, Z. T. Guo, T. Kiefer, and Z. Y. Liu
Clim. Past, 10, 2007–2052, https://doi.org/10.5194/cp-10-2007-2014, https://doi.org/10.5194/cp-10-2007-2014, 2014
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All regional monsoons belong to a cohesive global monsoon circulation system, albeit thateach regional subsystem has its own indigenous features. A comprehensive review of global monsoon variability reveals that regional monsoons can vary coherently across a range of timescales, from interannual up to orbital and tectonic. Study of monsoon variability from both global and regional perspectives is imperative and advantageous for integrated understanding of the modern and paleo-monsoon dynamics.
C. R. Maupin, J. W. Partin, C.-C. Shen, T. M. Quinn, K. Lin, F. W. Taylor, J. L. Banner, K. Thirumalai, and D. J. Sinclair
Clim. Past, 10, 1319–1332, https://doi.org/10.5194/cp-10-1319-2014, https://doi.org/10.5194/cp-10-1319-2014, 2014
L. Tan, Y. Cai, Z. An, L. Yi, H. Zhang, and S. Qin
Clim. Past, 7, 685–692, https://doi.org/10.5194/cp-7-685-2011, https://doi.org/10.5194/cp-7-685-2011, 2011
S. Dietrich and K. Seelos
Clim. Past, 6, 145–154, https://doi.org/10.5194/cp-6-145-2010, https://doi.org/10.5194/cp-6-145-2010, 2010
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