Articles | Volume 11, issue 2
https://doi.org/10.5194/cp-11-203-2015
© Author(s) 2015. 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-11-203-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
10 Feb 2015
Research article |
| 10 Feb 2015
Using simulations of the last millennium to understand climate variability seen in palaeo-observations: similar variation of Iceland–Scotland overflow strength and Atlantic Multidecadal Oscillation
K. Lohmann
CORRESPONDING AUTHOR
Max Planck Institute for Meteorology, Hamburg, Germany
J. Mignot
Climate and Environmental Physics and Oeschger Centre of Climate Change Research, University of Bern, Bern, Switzerland
Sorbonne Universités (UPMC, Univ Paris 06)-CNRS-IRD-MNHN, LOCEAN Laboratory, 4 place Jussieu, 75005 Paris, France
H. R. Langehaug
Bjerknes Centre for Climate Research, Bergen, Norway
Nansen Environmental and Remote Sensing Center, Bergen, Norway
J. H. Jungclaus
Max Planck Institute for Meteorology, Hamburg, Germany
D. Matei
Max Planck Institute for Meteorology, Hamburg, Germany
O. H. Otterå
Bjerknes Centre for Climate Research, Bergen, Norway
Uni Research, Bergen, Norway
Y. Q. Gao
Bjerknes Centre for Climate Research, Bergen, Norway
Nansen Environmental and Remote Sensing Center, Bergen, Norway
T. L. Mjell
Department of Earth Science, University of Bergen, Bergen, Norway
Bjerknes Centre for Climate Research, Bergen, Norway
U. S. Ninnemann
Department of Earth Science, University of Bergen, Bergen, Norway
Bjerknes Centre for Climate Research, Bergen, Norway
H. F. Kleiven
Department of Earth Science, University of Bergen, Bergen, Norway
Bjerknes Centre for Climate Research, Bergen, Norway
Related authors
Oliver Gutjahr, Nils Brüggemann, Helmuth Haak, Johann H. Jungclaus, Dian A. Putrasahan, Katja Lohmann, and Jin-Song von Storch
Geosci. Model Dev., 14, 2317–2349, https://doi.org/10.5194/gmd-14-2317-2021, https://doi.org/10.5194/gmd-14-2317-2021, 2021
Short summary
Short summary
We compare four ocean vertical mixing schemes in 100-year coupled simulations with the Max Planck Institute Earth System Model (MPI-ESM1.2) and analyse their model biases. Overall, the mixing schemes modify biases in the ocean interior that vary with region and variable but produce a similar global bias pattern. We therefore cannot classify any scheme as superior but conclude that the chosen mixing scheme may be important for regional biases.
Reinhard Schiemann, Panos Athanasiadis, David Barriopedro, Francisco Doblas-Reyes, Katja Lohmann, Malcolm J. Roberts, Dmitry V. Sein, Christopher D. Roberts, Laurent Terray, and Pier Luigi Vidale
Weather Clim. Dynam., 1, 277–292, https://doi.org/10.5194/wcd-1-277-2020, https://doi.org/10.5194/wcd-1-277-2020, 2020
Short summary
Short summary
In blocking situations the westerly atmospheric flow in the midlatitudes is blocked by near-stationary high-pressure systems. Blocking can be associated with extremes such as cold spells and heat waves. Climate models are known to underestimate blocking occurrence. Here, we assess the latest generation of models and find improvements in simulated blocking, partly due to increases in model resolution. These new models are therefore more suitable for studying climate extremes related to blocking.
Oliver Gutjahr, Dian Putrasahan, Katja Lohmann, Johann H. Jungclaus, Jin-Song von Storch, Nils Brüggemann, Helmuth Haak, and Achim Stössel
Geosci. Model Dev., 12, 3241–3281, https://doi.org/10.5194/gmd-12-3241-2019, https://doi.org/10.5194/gmd-12-3241-2019, 2019
Short summary
Short summary
We analyse how climatic mean states of the atmosphere and ocean change with increasing the horizontal model resolution of the Max Planck Institute Earth System Model (MPI-ESM1.2) and how they are affected by the representation of vertical mixing in the ocean. It is in particular a high-resolution ocean that reduces biases not only in the ocean but also in the atmosphere. The vertical mixing scheme affects the strength and stability of the Atlantic meridional overturning circulation (AMOC).
Manu Anna Thomas, Abhay Devasthale, Torben Koenigk, Klaus Wyser, Malcolm Roberts, Christopher Roberts, and Katja Lohmann
Geosci. Model Dev., 12, 1679–1702, https://doi.org/10.5194/gmd-12-1679-2019, https://doi.org/10.5194/gmd-12-1679-2019, 2019
Short summary
Short summary
Cloud processes occur at scales ranging from few micrometres to hundreds of kilometres. Their representation in global climate models and their fidelity are thus sensitive to the choice of spatial resolution. Here, cloud radiative effects simulated by models are evaluated using a satellite dataset, with a focus on investigating the sensitivity to spatial resolution. The evaluations are carried out using two approaches: the traditional statistical comparisons and the process-oriented evaluation.
J. H. Jungclaus, K. Lohmann, and D. Zanchettin
Clim. Past, 10, 2201–2213, https://doi.org/10.5194/cp-10-2201-2014, https://doi.org/10.5194/cp-10-2201-2014, 2014
Short summary
Short summary
Temperature reconstructions for the Atlantic Water layer in Fram Strait have previously revealed a dramatic warming during the 20th century that is unprecedented in the last 2000 years. Our study presents results from climate model simulations over the last millennium that are able to reproduce such changes and relate them to increased oceanic heat transports to the Arctic and to a re-organization of the North Atlantic ocean circulation caused by global warming.
K. Lohmann, J. H. Jungclaus, D. Matei, J. Mignot, M. Menary, H. R. Langehaug, J. Ba, Y. Gao, O. H. Otterå, W. Park, and S. Lorenz
Ocean Sci., 10, 227–241, https://doi.org/10.5194/os-10-227-2014, https://doi.org/10.5194/os-10-227-2014, 2014
Evelien J. C. van Dijk, Christoph C. Raible, Michael Sigl, Johann Jungclaus, and Heinz Wanner
Clim. Past Discuss., https://doi.org/10.5194/cp-2024-79, https://doi.org/10.5194/cp-2024-79, 2024
Preprint under review for CP
Short summary
Short summary
The temperature in the past 4000 years consisted of warm and cold periods, initiated by external forcing. But, these periods are not consistent through time and space. We use climate models and reconstructions to study to which extent the periods are reflected in the European climate. We find that on local scales, the chaotic nature of the climate system is larger than the external forcing. This study shows that these periods have to be used very carefully when studying a local site.
Swantje Bastin, Aleksei Koldunov, Florian Schütte, Oliver Gutjahr, Marta Agnieszka Mrozowska, Tim Fischer, Radomyra Shevchenko, Arjun Kumar, Nikolay Koldunov, Helmuth Haak, Nils Brüggemann, Rebecca Hummels, Mia Sophie Specht, Johann Jungclaus, Sergey Danilov, Marcus Dengler, and Markus Jochum
EGUsphere, https://doi.org/10.5194/egusphere-2024-2281, https://doi.org/10.5194/egusphere-2024-2281, 2024
Short summary
Short summary
Vertical mixing is an important process e.g. for tropical sea surface temperature, but cannot be resolved by ocean models. Comparisons of mixing schemes and settings have usually been done with a single model, sometimes yielding conflicting results. We systematically compare two widely used schemes, TKE and KPP, with different parameter settings, in two different ocean models, and show that most effects from mixing scheme parameter changes are model dependent.
Félix García-Pereira, Jesús Fidel González-Rouco, Camilo Melo-Aguilar, Norman Julius Steinert, Elena García-Bustamante, Philip de Vrese, Johann Jungclaus, Stephan Lorenz, Stefan Hagemann, Francisco José Cuesta-Valero, Almudena García-García, and Hugo Beltrami
Earth Syst. Dynam., 15, 547–564, https://doi.org/10.5194/esd-15-547-2024, https://doi.org/10.5194/esd-15-547-2024, 2024
Short summary
Short summary
According to climate model estimates, the land stored 2 % of the system's heat excess in the last decades, while observational studies show it was around 6 %. This difference stems from these models using land components that are too shallow to constrain land heat uptake. Deepening the land component does not affect the surface temperature. This result can be used to derive land heat uptake estimates from different sources, which are much closer to previous observational reports.
Roberto Bilbao, Pablo Ortega, Didier Swingedouw, Leon Hermanson, Panos Athanasiadis, Rosie Eade, Marion Devilliers, Francisco Doblas-Reyes, Nick Dunstone, An-Chi Ho, William Merryfield, Juliette Mignot, Dario Nicolì, Margarida Samsó, Reinel Sospedra-Alfonso, Xian Wu, and Stephen Yeager
Earth Syst. Dynam., 15, 501–525, https://doi.org/10.5194/esd-15-501-2024, https://doi.org/10.5194/esd-15-501-2024, 2024
Short summary
Short summary
In recent decades three major volcanic eruptions have occurred: Mount Agung in 1963, El Chichón in 1982 and Mount Pinatubo in 1991. In this article we explore the climatic impacts of these volcanic eruptions with a purposefully designed set of simulations from six CMIP6 decadal prediction systems. We analyse the radiative and dynamical responses and show that including the volcanic forcing in these predictions is important to reproduce the observed surface temperature variations.
Lara Wallberg, Laura Suarez-Gutierrez, Daniela Matei, and Wolfgang A. Müller
Earth Syst. Dynam., 15, 1–14, https://doi.org/10.5194/esd-15-1-2024, https://doi.org/10.5194/esd-15-1-2024, 2024
Short summary
Short summary
European summer temperatures are influenced by mechanisms on different timescales. We find that timescales of 5 to 10 years dominate the changes in summer temperature over large parts of the continent. Further, we find that specific processes within the North Atlantic, affecting the storage and transport of heat, cause changes in the atmosphere and extremely warm European summers. Our findings could be used for better forecasts of extremely warm European summers several years ahead.
Bjørg Risebrobakken, Mari F. Jensen, Helene R. Langehaug, Tor Eldevik, Anne Britt Sandø, Camille Li, Andreas Born, Erin Louise McClymont, Ulrich Salzmann, and Stijn De Schepper
Clim. Past, 19, 1101–1123, https://doi.org/10.5194/cp-19-1101-2023, https://doi.org/10.5194/cp-19-1101-2023, 2023
Short summary
Short summary
In the observational period, spatially coherent sea surface temperatures characterize the northern North Atlantic at multidecadal timescales. We show that spatially non-coherent temperature patterns are seen both in further projections and a past warm climate period with a CO2 level comparable to the future low-emission scenario. Buoyancy forcing is shown to be important for northern North Atlantic temperature patterns.
Guillaume Gastineau, Claude Frankignoul, Yongqi Gao, Yu-Chiao Liang, Young-Oh Kwon, Annalisa Cherchi, Rohit Ghosh, Elisa Manzini, Daniela Matei, Jennifer Mecking, Lingling Suo, Tian Tian, Shuting Yang, and Ying Zhang
The Cryosphere, 17, 2157–2184, https://doi.org/10.5194/tc-17-2157-2023, https://doi.org/10.5194/tc-17-2157-2023, 2023
Short summary
Short summary
Snow cover variability is important for many human activities. This study aims to understand the main drivers of snow cover in observations and models in order to better understand it and guide the improvement of climate models and forecasting systems. Analyses reveal a dominant role for sea surface temperature in the Pacific. Winter snow cover is also found to have important two-way interactions with the troposphere and stratosphere. No robust influence of the sea ice concentration is found.
Laura C. Jackson, Eduardo Alastrué de Asenjo, Katinka Bellomo, Gokhan Danabasoglu, Helmuth Haak, Aixue Hu, Johann Jungclaus, Warren Lee, Virna L. Meccia, Oleg Saenko, Andrew Shao, and Didier Swingedouw
Geosci. Model Dev., 16, 1975–1995, https://doi.org/10.5194/gmd-16-1975-2023, https://doi.org/10.5194/gmd-16-1975-2023, 2023
Short summary
Short summary
The Atlantic meridional overturning circulation (AMOC) has an important impact on the climate. There are theories that freshening of the ocean might cause the AMOC to cross a tipping point (TP) beyond which recovery is difficult; however, it is unclear whether TPs exist in global climate models. Here, we outline a set of experiments designed to explore AMOC tipping points and sensitivity to additional freshwater input as part of the North Atlantic Hosing Model Intercomparison Project (NAHosMIP).
Evelien van Dijk, Ingar Mørkestøl Gundersen, Anna de Bode, Helge Høeg, Kjetil Loftsgarden, Frode Iversen, Claudia Timmreck, Johann Jungclaus, and Kirstin Krüger
Clim. Past, 19, 357–398, https://doi.org/10.5194/cp-19-357-2023, https://doi.org/10.5194/cp-19-357-2023, 2023
Short summary
Short summary
The mid-6th century was one of the coldest periods of the last 2000 years as characterized by great societal changes. Here, we study the effect of the volcanic double event in 536 CE and 540 CE on climate and society in southern Norway. The combined climate and growing degree day models and high-resolution pollen and archaeological records reveal that the northern and western sites are vulnerable to crop failure with possible abandonment of farms, whereas the southeastern site is more resilient.
Cathy Hohenegger, Peter Korn, Leonidas Linardakis, René Redler, Reiner Schnur, Panagiotis Adamidis, Jiawei Bao, Swantje Bastin, Milad Behravesh, Martin Bergemann, Joachim Biercamp, Hendryk Bockelmann, Renate Brokopf, Nils Brüggemann, Lucas Casaroli, Fatemeh Chegini, George Datseris, Monika Esch, Geet George, Marco Giorgetta, Oliver Gutjahr, Helmuth Haak, Moritz Hanke, Tatiana Ilyina, Thomas Jahns, Johann Jungclaus, Marcel Kern, Daniel Klocke, Lukas Kluft, Tobias Kölling, Luis Kornblueh, Sergey Kosukhin, Clarissa Kroll, Junhong Lee, Thorsten Mauritsen, Carolin Mehlmann, Theresa Mieslinger, Ann Kristin Naumann, Laura Paccini, Angel Peinado, Divya Sri Praturi, Dian Putrasahan, Sebastian Rast, Thomas Riddick, Niklas Roeber, Hauke Schmidt, Uwe Schulzweida, Florian Schütte, Hans Segura, Radomyra Shevchenko, Vikram Singh, Mia Specht, Claudia Christine Stephan, Jin-Song von Storch, Raphaela Vogel, Christian Wengel, Marius Winkler, Florian Ziemen, Jochem Marotzke, and Bjorn Stevens
Geosci. Model Dev., 16, 779–811, https://doi.org/10.5194/gmd-16-779-2023, https://doi.org/10.5194/gmd-16-779-2023, 2023
Short summary
Short summary
Models of the Earth system used to understand climate and predict its change typically employ a grid spacing of about 100 km. Yet, many atmospheric and oceanic processes occur on much smaller scales. In this study, we present a new model configuration designed for the simulation of the components of the Earth system and their interactions at kilometer and smaller scales, allowing an explicit representation of the main drivers of the flow of energy and matter by solving the underlying equations.
Shih-Wei Fang, Claudia Timmreck, Johann Jungclaus, Kirstin Krüger, and Hauke Schmidt
Earth Syst. Dynam., 13, 1535–1555, https://doi.org/10.5194/esd-13-1535-2022, https://doi.org/10.5194/esd-13-1535-2022, 2022
Short summary
Short summary
The early 19th century was the coldest period over the past 500 years, when strong tropical volcanic events and a solar minimum coincided. This study quantifies potential surface cooling from the solar and volcanic forcing in the early 19th century with large ensemble simulations, and identifies the regions that their impacts cannot be simply additive. The cooling perspective of Arctic amplification exists in both solar and post-volcano period with the albedo feedback as the main contribution.
Evelien van Dijk, Johann Jungclaus, Stephan Lorenz, Claudia Timmreck, and Kirstin Krüger
Clim. Past, 18, 1601–1623, https://doi.org/10.5194/cp-18-1601-2022, https://doi.org/10.5194/cp-18-1601-2022, 2022
Short summary
Short summary
A double volcanic eruption in 536 and 540 CE caused one of the coldest decades during the last 2000 years. We analyzed new climate model simulations from that period and found a cooling of up to 2°C and a sea-ice extent up to 200 km further south. Complex interactions between sea ice and ocean circulation lead to a reduction in the northward ocean heat transport, which makes the sea ice extend further south; this in turn leads to a surface cooling up to 20 years after the eruptions.
Xiaoxu Shi, Martin Werner, Carolin Krug, Chris M. Brierley, Anni Zhao, Endurance Igbinosa, Pascale Braconnot, Esther Brady, Jian Cao, Roberta D'Agostino, Johann Jungclaus, Xingxing Liu, Bette Otto-Bliesner, Dmitry Sidorenko, Robert Tomas, Evgeny M. Volodin, Hu Yang, Qiong Zhang, Weipeng Zheng, and Gerrit Lohmann
Clim. Past, 18, 1047–1070, https://doi.org/10.5194/cp-18-1047-2022, https://doi.org/10.5194/cp-18-1047-2022, 2022
Short summary
Short summary
Since the orbital parameters of the past are different from today, applying the modern calendar to the past climate can lead to an artificial bias in seasonal cycles. With the use of multiple model outputs, we found that such a bias is non-ignorable and should be corrected to ensure an accurate comparison between modeled results and observational records, as well as between simulated past and modern climates, especially for the Last Interglacial.
Ingo Bethke, Yiguo Wang, François Counillon, Noel Keenlyside, Madlen Kimmritz, Filippa Fransner, Annette Samuelsen, Helene Langehaug, Lea Svendsen, Ping-Gin Chiu, Leilane Passos, Mats Bentsen, Chuncheng Guo, Alok Gupta, Jerry Tjiputra, Alf Kirkevåg, Dirk Olivié, Øyvind Seland, Julie Solsvik Vågane, Yuanchao Fan, and Tor Eldevik
Geosci. Model Dev., 14, 7073–7116, https://doi.org/10.5194/gmd-14-7073-2021, https://doi.org/10.5194/gmd-14-7073-2021, 2021
Short summary
Short summary
The Norwegian Climate Prediction Model version 1 (NorCPM1) is a new research tool for performing climate reanalyses and seasonal-to-decadal climate predictions. It adds data assimilation capability to the Norwegian Earth System Model version 1 (NorESM1) and has contributed output to the Decadal Climate Prediction Project (DCPP) as part of the sixth Coupled Model Intercomparison Project (CMIP6). We describe the system and evaluate its baseline, reanalysis and prediction performance.
Oliver Gutjahr, Nils Brüggemann, Helmuth Haak, Johann H. Jungclaus, Dian A. Putrasahan, Katja Lohmann, and Jin-Song von Storch
Geosci. Model Dev., 14, 2317–2349, https://doi.org/10.5194/gmd-14-2317-2021, https://doi.org/10.5194/gmd-14-2317-2021, 2021
Short summary
Short summary
We compare four ocean vertical mixing schemes in 100-year coupled simulations with the Max Planck Institute Earth System Model (MPI-ESM1.2) and analyse their model biases. Overall, the mixing schemes modify biases in the ocean interior that vary with region and variable but produce a similar global bias pattern. We therefore cannot classify any scheme as superior but conclude that the chosen mixing scheme may be important for regional biases.
Huiling Zou, Yongqi Gao, Helene R. Langehaug, Lei Yu, and Dong Guo
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-16, https://doi.org/10.5194/os-2021-16, 2021
Publication in OS not foreseen
Short summary
Short summary
This work focuses on the the relationships between winter sea ice variability and thermodynamic processes in sea ice in the Bering Sea. It has been found that in the Norwegian Earth System Model, thermodynamics in sea ice plays an important role in winter sea ice variability and they can contribute over 70 % of winter sea ice mass incresea in the Bering Sea. The results can be very helpful to give a better understanding of sea ice changes in an Earth System Model.
Renate Anna Irma Wilcke, Erik Kjellström, Changgui Lin, Daniela Matei, Anders Moberg, and Evangelos Tyrlis
Earth Syst. Dynam., 11, 1107–1121, https://doi.org/10.5194/esd-11-1107-2020, https://doi.org/10.5194/esd-11-1107-2020, 2020
Short summary
Short summary
Two long-lasting high-pressure systems in summer 2018 led to heat waves over Scandinavia and an extended summer period with devastating impacts on both agriculture and human life. Using five climate model ensembles, the unique 263-year Stockholm temperature time series and a composite 150-year time series for the whole of Sweden, we found that anthropogenic climate change has strongly increased the probability of a warm summer, such as the one observed in 2018, occurring in Sweden.
George C. Hurtt, Louise Chini, Ritvik Sahajpal, Steve Frolking, Benjamin L. Bodirsky, Katherine Calvin, Jonathan C. Doelman, Justin Fisk, Shinichiro Fujimori, Kees Klein Goldewijk, Tomoko Hasegawa, Peter Havlik, Andreas Heinimann, Florian Humpenöder, Johan Jungclaus, Jed O. Kaplan, Jennifer Kennedy, Tamás Krisztin, David Lawrence, Peter Lawrence, Lei Ma, Ole Mertz, Julia Pongratz, Alexander Popp, Benjamin Poulter, Keywan Riahi, Elena Shevliakova, Elke Stehfest, Peter Thornton, Francesco N. Tubiello, Detlef P. van Vuuren, and Xin Zhang
Geosci. Model Dev., 13, 5425–5464, https://doi.org/10.5194/gmd-13-5425-2020, https://doi.org/10.5194/gmd-13-5425-2020, 2020
Short summary
Short summary
To estimate the effects of human land use activities on the carbon–climate system, a new set of global gridded land use forcing datasets was developed to link historical land use data to eight future scenarios in a standard format required by climate models. This new generation of land use harmonization (LUH2) includes updated inputs, higher spatial resolution, more detailed land use transitions, and the addition of important agricultural management layers; it will be used for CMIP6 simulations.
Pierre Sepulchre, Arnaud Caubel, Jean-Baptiste Ladant, Laurent Bopp, Olivier Boucher, Pascale Braconnot, Patrick Brockmann, Anne Cozic, Yannick Donnadieu, Jean-Louis Dufresne, Victor Estella-Perez, Christian Ethé, Frédéric Fluteau, Marie-Alice Foujols, Guillaume Gastineau, Josefine Ghattas, Didier Hauglustaine, Frédéric Hourdin, Masa Kageyama, Myriam Khodri, Olivier Marti, Yann Meurdesoif, Juliette Mignot, Anta-Clarisse Sarr, Jérôme Servonnat, Didier Swingedouw, Sophie Szopa, and Delphine Tardif
Geosci. Model Dev., 13, 3011–3053, https://doi.org/10.5194/gmd-13-3011-2020, https://doi.org/10.5194/gmd-13-3011-2020, 2020
Short summary
Short summary
Our paper describes IPSL-CM5A2, an Earth system model that can be integrated for long (several thousands of years) climate simulations. We describe the technical aspects, assess the model computing performance and evaluate the strengths and weaknesses of the model, by comparing pre-industrial and historical runs to the previous-generation model simulations and to observations. We also present a Cretaceous simulation as a case study to show how the model simulates deep-time paleoclimates.
Juliette Mignot, Carlos Mejia, Charles Sorror, Adama Sylla, Michel Crépon, and Sylvie Thiria
Geosci. Model Dev., 13, 2723–2742, https://doi.org/10.5194/gmd-13-2723-2020, https://doi.org/10.5194/gmd-13-2723-2020, 2020
Short summary
Short summary
The most robust representation of climate is usually obtained by averaging a large number of simulations, thereby cancelling individual model errors. Here, we work towards an objective way of selecting the least biased models over a certain region, based on physical parameters. This statistical method based on a neural classifier and multi-correspondence analysis is illustrated here for the Senegalo-Mauritanian region, but it could potentially be developed for any other region or process.
Reinhard Schiemann, Panos Athanasiadis, David Barriopedro, Francisco Doblas-Reyes, Katja Lohmann, Malcolm J. Roberts, Dmitry V. Sein, Christopher D. Roberts, Laurent Terray, and Pier Luigi Vidale
Weather Clim. Dynam., 1, 277–292, https://doi.org/10.5194/wcd-1-277-2020, https://doi.org/10.5194/wcd-1-277-2020, 2020
Short summary
Short summary
In blocking situations the westerly atmospheric flow in the midlatitudes is blocked by near-stationary high-pressure systems. Blocking can be associated with extremes such as cold spells and heat waves. Climate models are known to underestimate blocking occurrence. Here, we assess the latest generation of models and find improvements in simulated blocking, partly due to increases in model resolution. These new models are therefore more suitable for studying climate extremes related to blocking.
Angélique Hameau, Thomas L. Frölicher, Juliette Mignot, and Fortunat Joos
Biogeosciences, 17, 1877–1895, https://doi.org/10.5194/bg-17-1877-2020, https://doi.org/10.5194/bg-17-1877-2020, 2020
Short summary
Short summary
Ocean deoxygenation and warming are observed and projected to intensify under continued greenhouse gas emissions. Whereas temperature is considered the main climate change indicator, we show that in certain regions, thermocline doxygenation may be detectable before warming.
Camilo Melo-Aguilar, J. Fidel González-Rouco, Elena García-Bustamante, Norman Steinert, Johann H. Jungclaus, Jorge Navarro, and Pedro J. Roldán-Gómez
Clim. Past, 16, 453–474, https://doi.org/10.5194/cp-16-453-2020, https://doi.org/10.5194/cp-16-453-2020, 2020
Short summary
Short summary
This study explores potential sources of bias on borehole-based temperature reconstruction from both methodological and physical factors using pseudo-proxy experiments that consider ensembles of simulations from the Community Earth System Model. The results indicate that both methodological and physical factors may have an impact on the estimation of the recent temperature trends at different spatial scales. Internal variability arises also as an important issue influencing pseudo-proxy results.
Simon Michel, Didier Swingedouw, Marie Chavent, Pablo Ortega, Juliette Mignot, and Myriam Khodri
Geosci. Model Dev., 13, 841–858, https://doi.org/10.5194/gmd-13-841-2020, https://doi.org/10.5194/gmd-13-841-2020, 2020
Short summary
Short summary
Natural archives such as sediments, ice, tree rings or speleothems provide indirect observations of past climate at local and regional scales. In this paper, we provide a computational device to properly make evaluated reconstructions of climate indices using these paleo-data. It provides optimizing cross-validation algorithms and four regression methods that are applied to the reconstruction of the North Atlantic Oscillation index and compared in this study.
Jérôme Sirven, Juliette Mignot, and Michel Crépon
Ocean Sci., 15, 1667–1690, https://doi.org/10.5194/os-15-1667-2019, https://doi.org/10.5194/os-15-1667-2019, 2019
Short summary
Short summary
In December 2002 and January 2003 satellite observations of chlorophyll showed a wavelike pattern with a wavelength of about 750 km south-west of the Cape Verde Peninsula. Such a pattern suggests the existence of a locally generated Rossby wave which slowly propagated westward. To verify this hypothesis a numerical study based on a simple model has been conducted. The numerical results are completed by an analytical study which evaluates the potential impact of the coastline shape.
Tine Nilsen, Dmitry V. Divine, Annika Hofgaard, Andreas Born, Johann Jungclaus, and Igor Drobyshev
Clim. Past Discuss., https://doi.org/10.5194/cp-2019-123, https://doi.org/10.5194/cp-2019-123, 2019
Revised manuscript not accepted
Short summary
Short summary
Using a set of three climate model simulations we cannot find a consistent relationship between atmospheric conditions favorable for forest fire activity in northern Scandinavia and weaker ocean circulation in the North Atlantic subpolar gyre on seasonal timescales. In the literature there is support of such a relationship for longer timescales. With the motivation to improve seasonal prediction systems, we conclude that the gyre circulation alone does not indicate forthcoming model drought.
Oliver Gutjahr, Dian Putrasahan, Katja Lohmann, Johann H. Jungclaus, Jin-Song von Storch, Nils Brüggemann, Helmuth Haak, and Achim Stössel
Geosci. Model Dev., 12, 3241–3281, https://doi.org/10.5194/gmd-12-3241-2019, https://doi.org/10.5194/gmd-12-3241-2019, 2019
Short summary
Short summary
We analyse how climatic mean states of the atmosphere and ocean change with increasing the horizontal model resolution of the Max Planck Institute Earth System Model (MPI-ESM1.2) and how they are affected by the representation of vertical mixing in the ocean. It is in particular a high-resolution ocean that reduces biases not only in the ocean but also in the atmosphere. The vertical mixing scheme affects the strength and stability of the Atlantic meridional overturning circulation (AMOC).
Manu Anna Thomas, Abhay Devasthale, Torben Koenigk, Klaus Wyser, Malcolm Roberts, Christopher Roberts, and Katja Lohmann
Geosci. Model Dev., 12, 1679–1702, https://doi.org/10.5194/gmd-12-1679-2019, https://doi.org/10.5194/gmd-12-1679-2019, 2019
Short summary
Short summary
Cloud processes occur at scales ranging from few micrometres to hundreds of kilometres. Their representation in global climate models and their fidelity are thus sensitive to the choice of spatial resolution. Here, cloud radiative effects simulated by models are evaluated using a satellite dataset, with a focus on investigating the sensitivity to spatial resolution. The evaluations are carried out using two approaches: the traditional statistical comparisons and the process-oriented evaluation.
Angélique Hameau, Juliette Mignot, and Fortunat Joos
Biogeosciences, 16, 1755–1780, https://doi.org/10.5194/bg-16-1755-2019, https://doi.org/10.5194/bg-16-1755-2019, 2019
Short summary
Short summary
The observed decrease of oxygen and warming in the ocean may adversely affect marine ecosystems and their services. We analyse results from an Earth system model for the last millennium and the 21st century. We find changes in temperature and oxygen due to fossil fuel burning and other human activities to exceed natural variations in many ocean regions already today. Natural variability is biased low in earlier studies neglecting forcing from past volcanic eruptions and solar change.
Doug M. Smith, James A. Screen, Clara Deser, Judah Cohen, John C. Fyfe, Javier García-Serrano, Thomas Jung, Vladimir Kattsov, Daniela Matei, Rym Msadek, Yannick Peings, Michael Sigmond, Jinro Ukita, Jin-Ho Yoon, and Xiangdong Zhang
Geosci. Model Dev., 12, 1139–1164, https://doi.org/10.5194/gmd-12-1139-2019, https://doi.org/10.5194/gmd-12-1139-2019, 2019
Short summary
Short summary
The Polar Amplification Model Intercomparison Project (PAMIP) is an endorsed contribution to the sixth Coupled Model Intercomparison Project (CMIP6). It will investigate the causes and global consequences of polar amplification through coordinated multi-model numerical experiments. This paper documents the experimental protocol.
Chuncheng Guo, Mats Bentsen, Ingo Bethke, Mehmet Ilicak, Jerry Tjiputra, Thomas Toniazzo, Jörg Schwinger, and Odd Helge Otterå
Geosci. Model Dev., 12, 343–362, https://doi.org/10.5194/gmd-12-343-2019, https://doi.org/10.5194/gmd-12-343-2019, 2019
Short summary
Short summary
In this paper, we describe and evaluate a new variant of the Norwegian Earth System Model (NorESM). It is a computationally efficient model that is designed for experiments such as paleoclimate, carbon cycle, and large ensemble simulations. The model, with various recent code updates, shows improved climate performance compared to the CMIP5 version of NorESM, while the model resolution remains similar.
Hanna Paulsen, Tatiana Ilyina, Johann H. Jungclaus, Katharina D. Six, and Irene Stemmler
Earth Syst. Dynam., 9, 1283–1300, https://doi.org/10.5194/esd-9-1283-2018, https://doi.org/10.5194/esd-9-1283-2018, 2018
Short summary
Short summary
We use an Earth system model to study the effects of light absorption by marine cyanobacteria on climate. We find that cyanobacteria have a considerable cooling effect on tropical SST with implications for ocean and atmosphere circulation patterns as well as for climate variability. The results indicate the importance of considering phytoplankton light absorption in climate models, and specifically highlight the role of cyanobacteria due to their regulative effect on tropical SST and climate.
Masa Kageyama, Pascale Braconnot, Sandy P. Harrison, Alan M. Haywood, Johann H. Jungclaus, Bette L. Otto-Bliesner, Jean-Yves Peterschmitt, Ayako Abe-Ouchi, Samuel Albani, Patrick J. Bartlein, Chris Brierley, Michel Crucifix, Aisling Dolan, Laura Fernandez-Donado, Hubertus Fischer, Peter O. Hopcroft, Ruza F. Ivanovic, Fabrice Lambert, Daniel J. Lunt, Natalie M. Mahowald, W. Richard Peltier, Steven J. Phipps, Didier M. Roche, Gavin A. Schmidt, Lev Tarasov, Paul J. Valdes, Qiong Zhang, and Tianjun Zhou
Geosci. Model Dev., 11, 1033–1057, https://doi.org/10.5194/gmd-11-1033-2018, https://doi.org/10.5194/gmd-11-1033-2018, 2018
Short summary
Short summary
The Paleoclimate Modelling Intercomparison Project (PMIP) takes advantage of the existence of past climate states radically different from the recent past to test climate models used for climate projections and to better understand these climates. This paper describes the PMIP contribution to CMIP6 (Coupled Model Intercomparison Project, 6th phase) and possible analyses based on PMIP results, as well as on other CMIP6 projects.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Montserrat Alonso-Garcia, Helga (Kikki) F. Kleiven, Jerry F. McManus, Paola Moffa-Sanchez, Wallace S. Broecker, and Benjamin P. Flower
Clim. Past, 13, 317–331, https://doi.org/10.5194/cp-13-317-2017, https://doi.org/10.5194/cp-13-317-2017, 2017
Short summary
Short summary
This study focuses on understanding climatic and oceanographic variations that took place during the last 1000 years. We studied sediment samples from the Labrador Sea, looking for evidence of events of freshwater and iceberg discharges to this region. The importance of this study is to evaluate when these events happened and their consequences. The freshening of the Labrador Sea region may have played a major role in promoting cooling during the 15th to 19th centuries.
Jonathan M. Gregory, Nathaelle Bouttes, Stephen M. Griffies, Helmuth Haak, William J. Hurlin, Johann Jungclaus, Maxwell Kelley, Warren G. Lee, John Marshall, Anastasia Romanou, Oleg A. Saenko, Detlef Stammer, and Michael Winton
Geosci. Model Dev., 9, 3993–4017, https://doi.org/10.5194/gmd-9-3993-2016, https://doi.org/10.5194/gmd-9-3993-2016, 2016
Short summary
Short summary
As a consequence of greenhouse gas emissions, changes in ocean temperature, salinity, circulation and sea level are expected in coming decades. Among the models used for climate projections for the 21st century, there is a large spread in projections of these effects. The Flux-Anomaly-Forced Model Intercomparison Project (FAFMIP) aims to investigate and explain this spread by prescribing a common set of changes in the input of heat, water and wind stress to the ocean in the participating models.
Stephen M. Griffies, Gokhan Danabasoglu, Paul J. Durack, Alistair J. Adcroft, V. Balaji, Claus W. Böning, Eric P. Chassignet, Enrique Curchitser, Julie Deshayes, Helge Drange, Baylor Fox-Kemper, Peter J. Gleckler, Jonathan M. Gregory, Helmuth Haak, Robert W. Hallberg, Patrick Heimbach, Helene T. Hewitt, David M. Holland, Tatiana Ilyina, Johann H. Jungclaus, Yoshiki Komuro, John P. Krasting, William G. Large, Simon J. Marsland, Simona Masina, Trevor J. McDougall, A. J. George Nurser, James C. Orr, Anna Pirani, Fangli Qiao, Ronald J. Stouffer, Karl E. Taylor, Anne Marie Treguier, Hiroyuki Tsujino, Petteri Uotila, Maria Valdivieso, Qiang Wang, Michael Winton, and Stephen G. Yeager
Geosci. Model Dev., 9, 3231–3296, https://doi.org/10.5194/gmd-9-3231-2016, https://doi.org/10.5194/gmd-9-3231-2016, 2016
Short summary
Short summary
The Ocean Model Intercomparison Project (OMIP) aims to provide a framework for evaluating, understanding, and improving the ocean and sea-ice components of global climate and earth system models contributing to the Coupled Model Intercomparison Project Phase 6 (CMIP6). This document defines OMIP and details a protocol both for simulating global ocean/sea-ice models and for analysing their output.
Anastasios Matsikaris, Martin Widmann, and Johann Jungclaus
Clim. Past, 12, 1555–1563, https://doi.org/10.5194/cp-12-1555-2016, https://doi.org/10.5194/cp-12-1555-2016, 2016
Short summary
Short summary
We have assimilated proxy-based (PAGES 2K) and instrumental (HadCRUT3v) observations into a General Circulation Model (MPI-ESM-CR). Assimilating instrumental data improves the performance of Data Assimilation. No skill on small spatial scales is however found for either of the two schemes. Errors in the assimilated data are therefore not the main reason for this lack of skill; continental mean temperatures cannot provide skill on small spatial scales in palaeoclimate reconstructions.
Jonathan J. Day, Steffen Tietsche, Mat Collins, Helge F. Goessling, Virginie Guemas, Anabelle Guillory, William J. Hurlin, Masayoshi Ishii, Sarah P. E. Keeley, Daniela Matei, Rym Msadek, Michael Sigmond, Hiroaki Tatebe, and Ed Hawkins
Geosci. Model Dev., 9, 2255–2270, https://doi.org/10.5194/gmd-9-2255-2016, https://doi.org/10.5194/gmd-9-2255-2016, 2016
Short summary
Short summary
Recent decades have seen significant developments in seasonal-to-interannual timescale climate prediction. However, until recently the potential of such systems to predict Arctic climate had not been assessed. This paper describes a multi-model predictability experiment which was run as part of the Arctic Predictability and Prediction On Seasonal to Interannual Timescales (APPOSITE) project. The main goal of APPOSITE was to quantify the timescales on which Arctic climate is predictable.
A. Matsikaris, M. Widmann, and J. Jungclaus
Clim. Past, 11, 81–93, https://doi.org/10.5194/cp-11-81-2015, https://doi.org/10.5194/cp-11-81-2015, 2015
Short summary
Short summary
We compare an off-line and an on-line ensemble-based data assimilation method, for the climate of the 17th century. Both schemes perform better than the simulations without DA, and similar skill on the continental and hemispheric scales is found. This indicates either a lack of control of the slow components in our setup or a lack of skill in the information propagation on decadal timescales. The temporal consistency of the analysis in the on-line method makes it generally more preferable.
J. H. Jungclaus, K. Lohmann, and D. Zanchettin
Clim. Past, 10, 2201–2213, https://doi.org/10.5194/cp-10-2201-2014, https://doi.org/10.5194/cp-10-2201-2014, 2014
Short summary
Short summary
Temperature reconstructions for the Atlantic Water layer in Fram Strait have previously revealed a dramatic warming during the 20th century that is unprecedented in the last 2000 years. Our study presents results from climate model simulations over the last millennium that are able to reproduce such changes and relate them to increased oceanic heat transports to the Arctic and to a re-organization of the North Atlantic ocean circulation caused by global warming.
K. Lohmann, J. H. Jungclaus, D. Matei, J. Mignot, M. Menary, H. R. Langehaug, J. Ba, Y. Gao, O. H. Otterå, W. Park, and S. Lorenz
Ocean Sci., 10, 227–241, https://doi.org/10.5194/os-10-227-2014, https://doi.org/10.5194/os-10-227-2014, 2014
T. Wang, H. J. Wang, O. H. Otterå, Y. Q. Gao, L. L. Suo, T. Furevik, and L. Yu
Atmos. Chem. Phys., 13, 12433–12450, https://doi.org/10.5194/acp-13-12433-2013, https://doi.org/10.5194/acp-13-12433-2013, 2013
O. Bothe, J. H. Jungclaus, and D. Zanchettin
Clim. Past, 9, 2471–2487, https://doi.org/10.5194/cp-9-2471-2013, https://doi.org/10.5194/cp-9-2471-2013, 2013
D. J. R. Thornalley, M. Blaschek, F. J. Davies, S. Praetorius, D. W. Oppo, J. F. McManus, I. R. Hall, H. Kleiven, H. Renssen, and I. N. McCave
Clim. Past, 9, 2073–2084, https://doi.org/10.5194/cp-9-2073-2013, https://doi.org/10.5194/cp-9-2073-2013, 2013
O. Bothe, J. H. Jungclaus, D. Zanchettin, and E. Zorita
Clim. Past, 9, 1089–1110, https://doi.org/10.5194/cp-9-1089-2013, https://doi.org/10.5194/cp-9-1089-2013, 2013
J. Segschneider, A. Beitsch, C. Timmreck, V. Brovkin, T. Ilyina, J. Jungclaus, S. J. Lorenz, K. D. Six, and D. Zanchettin
Biogeosciences, 10, 669–687, https://doi.org/10.5194/bg-10-669-2013, https://doi.org/10.5194/bg-10-669-2013, 2013
S. Tietsche, D. Notz, J. H. Jungclaus, and J. Marotzke
Ocean Sci., 9, 19–36, https://doi.org/10.5194/os-9-19-2013, https://doi.org/10.5194/os-9-19-2013, 2013
Related subject area
Subject: Climate Modelling | Archive: Modelling only | Timescale: Centennial-Decadal
Last Millennium Volcanic Forcing and Climate Response using SO2 Emissions
Utilising a multi-proxy to model comparison to constrain the season and regionally heterogeneous impacts of the Mt Samalas 1257 eruption
A multi-model assessment of the early last deglaciation (PMIP4 LDv1): a meltwater perspective
The unidentified eruption of 1809: a climatic cold case
South Pacific Subtropical High from the late Holocene to the end of the 21st century: insights from climate proxies and general circulation models
Oceanic response to changes in the WAIS and astronomical forcing during the MIS31 superinterglacial
Assimilation of pseudo-tree-ring-width observations into an atmospheric general circulation model
Continental-scale temperature variability in PMIP3 simulations and PAGES 2k regional temperature reconstructions over the past millennium
Impact of solar versus volcanic activity variations on tropospheric temperatures and precipitation during the Dalton Minimum
Changing correlation structures of the Northern Hemisphere atmospheric circulation from 1000 to 2100 AD
Using palaeo-climate comparisons to constrain future projections in CMIP5
Consistency of the multi-model CMIP5/PMIP3-past1000 ensemble
Climate of the last millennium: ensemble consistency of simulations and reconstructions
Variability of the ocean heat content during the last millennium – an assessment with the ECHO-g Model
Climate variability of the mid- and high-latitudes of the Southern Hemisphere in ensemble simulations from 1500 to 2000 AD
Evaluating climate model performance with various parameter sets using observations over the recent past
Using data assimilation to study extratropical Northern Hemisphere climate over the last millennium
Lauren R. Marshall, Anja Schmidt, Andrew P. Schurer, Nathan Luke Abraham, Lucie J. Lücke, Rob Wilson, Kevin Anchukaitis, Gabriele Hegerl, Ben Johnson, Bette L. Otto-Bliesner, Esther C. Brady, Myriam Khodri, and Kohei Yoshida
EGUsphere, https://doi.org/10.5194/egusphere-2024-1322, https://doi.org/10.5194/egusphere-2024-1322, 2024
Short summary
Short summary
Large volcanic eruptions have caused temperature deviations over the past 1000 years, however climate model results and reconstructions of surface cooling using tree-rings do not match. We explore this mismatch using the latest models and find a better match to tree-ring reconstructions for some eruptions. Our results show that the way in which eruptions are simulated in models matters for the comparison to tree-rings, particularly regarding the spatial spread of volcanic aerosol.
Laura Wainman, Lauren R. Marshall, and Anja Schmidt
Clim. Past, 20, 951–968, https://doi.org/10.5194/cp-20-951-2024, https://doi.org/10.5194/cp-20-951-2024, 2024
Short summary
Short summary
The Mt Samalas eruption had global-scale impacts on climate and has been linked to historical events throughout latter half of the 13th century. Using model simulations and multi-proxy data, we constrain the year and season of the eruption to summer 1257 and investigate the regional-scale variability in surface cooling following the eruption. We also evaluate our model-to-proxy comparison framework and discuss current limitations of the approach.
Brooke Snoll, Ruza Ivanovic, Lauren Gregoire, Sam Sherriff-Tadano, Laurie Menviel, Takashi Obase, Ayako Abe-Ouchi, Nathaelle Bouttes, Chengfei He, Feng He, Marie Kapsch, Uwe Mikolajewicz, Juan Muglia, and Paul Valdes
Clim. Past, 20, 789–815, https://doi.org/10.5194/cp-20-789-2024, https://doi.org/10.5194/cp-20-789-2024, 2024
Short summary
Short summary
Geological records show rapid climate change throughout the recent deglaciation. The drivers of these changes are still misunderstood but are often attributed to shifts in the Atlantic Ocean circulation from meltwater input. A cumulative effort to understand these processes prompted numerous simulations of this period. We use these to explain the chain of events and our collective ability to simulate them. The results demonstrate the importance of the meltwater amount used in the simulation.
Claudia Timmreck, Matthew Toohey, Davide Zanchettin, Stefan Brönnimann, Elin Lundstad, and Rob Wilson
Clim. Past, 17, 1455–1482, https://doi.org/10.5194/cp-17-1455-2021, https://doi.org/10.5194/cp-17-1455-2021, 2021
Short summary
Short summary
The 1809 eruption is one of the most recent unidentified volcanic eruptions with a global climate impact. We demonstrate that climate model simulations of the 1809 eruption show generally good agreement with many large-scale temperature reconstructions and early instrumental records for a range of radiative forcing estimates. In terms of explaining the spatially heterogeneous and temporally delayed Northern Hemisphere cooling suggested by tree-ring networks, the investigation remains open.
Valentina Flores-Aqueveque, Maisa Rojas, Catalina Aguirre, Paola A. Arias, and Charles González
Clim. Past, 16, 79–99, https://doi.org/10.5194/cp-16-79-2020, https://doi.org/10.5194/cp-16-79-2020, 2020
Short summary
Short summary
The South Pacific Subtropical High (SPSH) is a main feature of the South American (SA) climate. We analyzed its behavior during two extreme temperature events based on paleoclimate records and climate models. The SPSH expands (contracts) in warm (cold) periods. The changes affect other elements of the SA climate like the strength of the southerly winds and the position of the westerly wind belt. Projections indicate that this expansion and its consequences will continue during the 21st century.
Flavio Justino, Douglas Lindemann, Fred Kucharski, Aaron Wilson, David Bromwich, and Frode Stordal
Clim. Past, 13, 1081–1095, https://doi.org/10.5194/cp-13-1081-2017, https://doi.org/10.5194/cp-13-1081-2017, 2017
Short summary
Short summary
These modeling results have enormous implications for paleoreconstructions of the MIS31 climate that assume overall ice-free conditions in the vicinity of the Antarctic continent. Since these reconstructions may depict dominant signals in a particular time interval and locale, they cannot be assumed to geographically represent large-scale domains, and their ability to reproduce long-term environmental conditions should be considered with care.
Walter Acevedo, Bijan Fallah, Sebastian Reich, and Ulrich Cubasch
Clim. Past, 13, 545–557, https://doi.org/10.5194/cp-13-545-2017, https://doi.org/10.5194/cp-13-545-2017, 2017
Short summary
Short summary
The purpose of this study is to contribute to the present knowledge of paleo data assimilation techniques by addressing the following two questions: (i) Does the off-line regime naturally appear for the assimilation of tree-ring-width records into an AGCM? (ii) Is the fuzzy logic (FL)-based extension of a forward model still useful to improve the performance of a time-averaged ensemble Kalman filter technique when a climate model is used?
PAGES 2k-PMIP3 group
Clim. Past, 11, 1673–1699, https://doi.org/10.5194/cp-11-1673-2015, https://doi.org/10.5194/cp-11-1673-2015, 2015
Short summary
Short summary
A comparison of model simulations and reconstructions at the continental scale over the past millennium indicates that models are in relatively good agreement with temperature reconstructions for Northern Hemisphere regions, particularly in the Arctic. This is likely due to the relatively large amplitude of the externally forced response across northern and high-latitudes regions. Conversely, models disagree strongly with the reconstructions in the Southern Hemisphere.
J. G. Anet, S. Muthers, E. V. Rozanov, C. C. Raible, A. Stenke, A. I. Shapiro, S. Brönnimann, F. Arfeuille, Y. Brugnara, J. Beer, F. Steinhilber, W. Schmutz, and T. Peter
Clim. Past, 10, 921–938, https://doi.org/10.5194/cp-10-921-2014, https://doi.org/10.5194/cp-10-921-2014, 2014
C. C. Raible, F. Lehner, J. F. González-Rouco, and L. Fernández-Donado
Clim. Past, 10, 537–550, https://doi.org/10.5194/cp-10-537-2014, https://doi.org/10.5194/cp-10-537-2014, 2014
G. A. Schmidt, J. D. Annan, P. J. Bartlein, B. I. Cook, E. Guilyardi, J. C. Hargreaves, S. P. Harrison, M. Kageyama, A. N. LeGrande, B. Konecky, S. Lovejoy, M. E. Mann, V. Masson-Delmotte, C. Risi, D. Thompson, A. Timmermann, L.-B. Tremblay, and P. Yiou
Clim. Past, 10, 221–250, https://doi.org/10.5194/cp-10-221-2014, https://doi.org/10.5194/cp-10-221-2014, 2014
O. Bothe, J. H. Jungclaus, and D. Zanchettin
Clim. Past, 9, 2471–2487, https://doi.org/10.5194/cp-9-2471-2013, https://doi.org/10.5194/cp-9-2471-2013, 2013
O. Bothe, J. H. Jungclaus, D. Zanchettin, and E. Zorita
Clim. Past, 9, 1089–1110, https://doi.org/10.5194/cp-9-1089-2013, https://doi.org/10.5194/cp-9-1089-2013, 2013
P. Ortega, M. Montoya, F. González-Rouco, H. Beltrami, and D. Swingedouw
Clim. Past, 9, 547–565, https://doi.org/10.5194/cp-9-547-2013, https://doi.org/10.5194/cp-9-547-2013, 2013
S. B. Wilmes, C. C. Raible, and T. F. Stocker
Clim. Past, 8, 373–390, https://doi.org/10.5194/cp-8-373-2012, https://doi.org/10.5194/cp-8-373-2012, 2012
M. F. Loutre, A. Mouchet, T. Fichefet, H. Goosse, H. Goelzer, and P. Huybrechts
Clim. Past, 7, 511–526, https://doi.org/10.5194/cp-7-511-2011, https://doi.org/10.5194/cp-7-511-2011, 2011
M. Widmann, H. Goosse, G. van der Schrier, R. Schnur, and J. Barkmeijer
Clim. Past, 6, 627–644, https://doi.org/10.5194/cp-6-627-2010, https://doi.org/10.5194/cp-6-627-2010, 2010
Cited articles
Ammann, C., Meehl, G., Washington, W., and Zender, C.: A monthly and latitudinally varying volcanic forcing dataset in simulations of 20th century climate, Geophys. Res. Lett., 30, 1657, https://doi.org/10.1029/2003GL016875, 2003.
Ba, J., Keenlyside, N., Latif, M., Park, W., Ding, H., Lohmann, K., Mignot, J., Menary, M., Otterå, O. H., Wouters, B., Salas-Melia, D., Oka, A., Belluci, A., and Volodin, E.: Multi-model comparison for North Atlantic multi-decadal variability, Clim. Dynam., 43, 2333–2348, 2014.
Bleck, R. and Smith, L.: A wind-driven isopycnic coordinate model of the north and equatorial Atlantic Ocean, 1. Model development and supporting experiments, J. Geophys. Res., 95, 3273–3285, 1990.
Bleck, R., Rooth, C., Hu, D., and Smith, L.: Salinity-driven thermocline transients in a wind- and thermohaline-forced isopycnic coordinate model of the North Atlantic, J. Phys. Oceanogr., 22, 1486–1505, 1992.
Boessenkool, K., Hall, I. R., Elderfield, H., and Yashayaev, I.: North Atlantic climate and deep-ocean flow speed changes during the last 230 years, Geophys. Res. Lett., 34, L13614, https://doi.org/10.1029/2007GL030285, 2007.
Crowley, T. J., Baum, S. K., Kim, K. Y., Hegerl, G. C., and Hyde, W. T.: Modeling ocean heat content changes during the last millennium, Geophys. Res. Lett., 30, 1932, https://doi.org/10.1029/2003GL017801, 2003.
Crowley, T. J., Zielinski, G., Vinther, B., Udisti, R., Kreutz, K., Cole-Dai, J., and Castellano, J.: Volcanism and the Little Ice Age, PAGES Newsletter, 16, 22–23, 2008.
Delworth, T. and Mann, M. E.: Observed and simulated multi-decadal variability in the Northern Hemisphere, Clim. Dynam., 16, 661–676, 2000.
Déqué, M., Dreveton, C., Braun, A., and Cariolle, D.: The ARPEGE/IFS atmosphere model: A contribution to the French community climate modelling, Clim. Dynam., 10, 249–266, 1994.
Fichefet, T., and Maqueda, M. A. M.: Sensitivity of a global sea ice model to the treatment of ice thermodynamics and dynamics, J. Geophys. Res., 102, 12609–12646, 1997.
Furevik, T., Bentsen, M., Drange, H., Kindem, I., Kvamstø N. G., and Sorteberg, A.: Description and evaluation of the Bergen climate model: ARPEGE coupled with MICOM, Clim. Dynam., 21, 27–51, 2003.
Gao, C., Robock, A., and Ammann, C.: Volcanic forcing of climate over the last 1500 years: An improved ice-core based index for climate models, J. Geophys. Res., 113, D2311, https://doi.org/10.1029/2008JD010239, 2008.
Gastineau, G. and Frankignoul, C.: Cold-season atmospheric response to the natural variability of the Atlantic meridional overturning circulation, Clim. Dynam., 39, 37–57, 2012.
Goosse, H. and Renssen, H.: Regional response of the climate system to solar forcing: the role of the ocean, Space Sci. Rev., 125, 227–235, 2006.
Gray, S., Graumlich, L., Betancourt, J., and Pederson, G.: A tree-ring based reconstruction of the Atlantic multidecadal oscillation since 1567 AD, Geophys. Res. Lett., 31, L12205, https://doi.org/10.1029/2004GL019932, 2004.
Hansen, B. and Østerhus, S.: Faroe Bank Channel overflow 1995–2005, Prog. Oceanogr., 75, 817–856, 2007.
Hansen, B., Turrell, W., and Østerhus, S.: Decreasing overflow from the Nordic seas into the Atlantic Ocean through the Faroe Bank channel since 1950, Nature, 411, 927–930, 2001.
Hansen, B., Østerhus, S., Turrell, B., Jónsson, S., Valdimarsson, H., Hátún H., and Olsen, S. M.: The inflow of Atlantic water, heat, and salt to the Nordic Seas across the Greenland-Scotland Ridge, in: Arctic–Subarctic Ocean Fluxes: Defining the role of the Northern Seas in Climate, edited by: Dickson, D., Meincke, J., and Rhines, P., Springer Verlag, 15–43, 2008.
Hourdin, F., Musat, I., Bony, S., Braconnot, P., Codron, F., Dufresne, J., Fairhead, L., Filiberti, M. A., Friedlingstein, P., Grandpeix, J. Y., Krinner, G., Levan, P., Li, Z., and Lott, F.: The LMDZ4 general circulation model: climate performance and sensitivity to parametrized physics with emphasis on tropical convection, Clim. Dynam., 27, 787–813, 2006.
Jungclaus, J. H., Haak, H., Latif, M., and Mikolajewicz, U.: Arctic–North Atlantic interactions and multidecadal variability of the meridional overturning circulation, J. Clim., 18, 4013–4031, 2005.
Jungclaus, J. H., Macrander, A., and Käse, R.: Modelling the overflows across the Greenland-Scotland Ridge, in: Arctic–Subarctic Ocean Fluxes: Defining the role of the Northern Seas in Climate, edited by: Dickson, D., Meincke, J., and Rhines, P., Springer Verlag, 527–549, 2008.
Jungclaus, J. H., Fischer, N., Haak, H., Lohmann, K., Marotzke, J., Matei, D., Mikolajewicz, U., Notz, D., and von Storch, J. S.: Characteristics of the ocean simulations in Max Planck Institute Ocean Model (MPIOM), the ocean component of the MPI-Earth System Model, J. Adv. Model. Earth Syst., 5, 422–446, 2013.
Jungclaus, J. H., Lohmann, K., and Zanchettin, D.: Enhanced 20th-century heat transfer to the Arctic simulated in the context of climate variations over the last millennium, Clim. Past, 10, 2201–2213, https://doi.org/10.5194/cp-10-2201-2014, 2015.
Kavvada, A., Ruiz-Barradas, A., and Nigam, S.: AMO's structure and climate footprint in observations and IPCC AR5 climate simulations, Clim. Dynam., 41, 1345–1364, 2013.
Knight, J., Allan, R., Folland, C., Vellinga, M., and Mann, M. E.: A signature of persistent natural thermohaline circulation cycles in observed climate, Geophys. Res. Lett., 32, L20708, https://doi.org/10.1029/2005GL024233, 2005.
Köhl, A. and Stammer, D.: Variability of the meridional overturning in the North Atlantic from the 50-year GECCO state estimate, J. Phys. Oceanogr., 38, 1913–1930, 2008.
Langehaug, H. R., Medhaug, I., Eldevik, T., and Otterå, O. H.: Arctic/Atlantic exchanges via the subpolar gyre, J. Clim., 25, 2421–2439, 2012a.
Langehaug, H. R., Rhines, P. B., Eldevik, T., Mignot, J., and Lohmann, K.: Water mass transformation and the North Atlantic Current in three multicentury climate model simulations, J. Geophys. Res., 117, C11001, https://doi.org/10.1029/2012JC008021, 2012b.
Latif, M., Roeckner, E., Botzet, M., Esch, M., Haak, H., Hagemann, S., Jungclaus, J. H., Legutke, S., Marsland, S., Mikolajewicz, U., and Mitchell, J.: Reconstructing, monitoring and predicting decadal-scale changes in the North Atlantic thermohaline circulation with sea surface temperature, J. Clim., 17, 1605–1614, 2004.
Lehner, F., Born, A., Raible, C. C., and Stocker, T. S.: Amplified inception of European Little Ice Age by sea ice – ocean – atmosphere feedbacks, J. Clim., 26, 7586–7602, 2013.
Lohmann, K., Jungclaus, J. H., Matei, D., Mignot, J., Menary, M., Langehaug, H. R., Ba, J., Gao, Y. Q., Otterå, O. H., Park, W., and Lorenz, S.: The role of subpolar deep water formation and Nordic Seas overflows in simulated multidecadal variability of the Atlantic meridional overturning circulation, Ocean Sci., 10, 227–241, 2014.
Madec, G., Delecluse, P., Imbard, M., and Levy, M.: OPA 8.1, ocean general circulation model reference manual, Notes du pole de modélisation, 11, Institut Pierre-Simon Laplace (IPSL), Paris, France, 91 pp., 1998.
Mann, M. E., Zhang, Z., Rutherford, S., Bradley, R. S., Hughes, M. K., Shindell, D., Ammann, C., Faluvegi, G., and Ni, F.: Global signatures and dynamical origins of the Little Ice Age and Medieval Climate Anomaly, Science, 326, 1256–1260, 2009.
Marsland, S., Haak, H., Jungclaus, J. H., Latif, M., and Röske, F.: The Max Planck Institute global ocean/sea ice model with orthogonal curvilinear coordinates, Ocean Modell., 5, 91–127, 2003.
Marti, O., Braconnot, P., Dufresne, J. L., Bellier, J., Benshila, R., Bony, S., Brockmann, P., Cadule, P., Caubel, A., Codron, F., de Noblet, N., Denvil, S., Fairhead, L., Fichefet, T., Foujols, M. A., Friedlingstein, P., Goosse, H., Grandpeix, J. Y., Guilyardi, E., Hourdin, F., Idelkadi, A., Kageyama, M., Krinner, G., Lévy, C., Madec, G., Mignot, J., Musat, I., Swingedouw, D., and Talandier, C.: Key features of the IPSL ocean atmosphere model and its sensitivity to atmospheric resolution, Clim. Dynam., 34, 1–26, 2010.
Menary, M., Park, W., Lohmann, K., Vellinga, M., Palmer, M., Latif, M., and Jungclaus, J. H.: A multimodel comparison of centennial Atlantic meridional overturning circulation variability, Clim. Dynam., 38, 2377–2388, 2012.
Mignot, J., Khodri, M., Frankignoul, C., and Servonnat, J.: Volcanic impact on the Atlantic Ocean over the last millennium, Clim. Past, 7, 1439–1455, 2011.
Mjell, T. L., Ninnemann, U. S., Kleiven, H. F., and Hall, I. R.: Multidecadal changes in Iceland Scotland Overflow Water vigor over the last 600 years and its relationship to climate, Geophys. Res. Lett., submitted, 2015.
Moreno-Chamarro, E., Zanchettin, D., Lohmann, K., and Jungclaus, J. H.: Internally generated decadal cold events in the northern North Atlantic and their possible implications for the demise of the Norse settlements in Greenland, Geophys. Res. Lett., https://doi.org/10.1002/2014GL062741, online first, 2015.
Msadek, R. and Frankignoul, C.: Atlantic multidecadal oceanic variability and its influence on the atmosphere in a climate model, Clim. Dynam., 33, 45–62, 2009.
Myneni, R. B., Nemani, R. R., and Running, S. W.: Estimation of global leaf area index and absorbed par using radiative transfer models, Ieee T. Geosci. Remote., 35, 1380–1393, 1997.
Notz, D., Haumann, A., Haak, H., Jungclaus, J. H., and Marotzke, J.: Sea-ice evolution in the Arctic as modeled by Max Planck Institute for Meteorology's Earth System Model, J. Adv. Model. Earth Syst., 5, 173–194, 2013.
Olsen, S. M., Hansen, B., Quadfasel, D., and Østerhus, S.: Observed and modeled stability of overflow across the Greenland–Scotland ridge, Nature, 455, 519–523, 2008.
Ortega, P., Montoya, M., González-Rouco, F., Mignot, J., and Legutke, S.: Variability of the Atlantic meridional overturning circulation in the last millennium and two IPCC scenarios, Clim. Dynam., 38, 1925–1947, 2012.
Otterå, O. H., Bentsen, M., Bethke, I., and Kvamstø, N. G.: Simulated pre-industrial climate in Bergen Climate Model (version 2): model description and large-scale circulation features, Geosci. Model Dev., 2, 197–212, 2009.
Otterå, O. H., Bentsen, M., Drange, H., and Suo, L.: External forcing as a metronome for Atlantic multidecadal variability, Nat. Geosci., 3, 688–694, 2010.
Park, W. and Latif, M.: Atlantic meridional overturning circulation response to idealized external forcing, Clim. Dynam., 39, 1709–1726, 2012.
Pongratz, J., Reick, C. H., Raddatz, T., and Claussen, M.: A reconstruction of global agricultural areas and land cover for the last millennium, Global Biogeochem. Cy., 22, GB3018, https://doi.org/10.1029/2007GB003153, 2008.
Salas-Melia, D.: A global coupled sea ice-ocean model, Ocean Modell., 4, 137–172, 2002.
Sandø, A. B., Nilsen, J. E. Ø., Eldevik, T., and Bentsen, M.: Mechanisms for variable North Atlantic – Nordic Seas exchanges, J. Geophys. Res., 117, C12006, https://doi.org/10.1029/2012JC008177, 2012.
Schlesinger, M. E. and Ramankutty, N.: An oscillation in the global climate system of period 65-70 years, Nature, 367, 723–726, 1994.
Schmidt, G., Jungclaus, J. H., Ammann, C., Bard, E., Braconnot, P., Crowley, T. J., Delaygue, G., Joos, F., Krivova, N. A., Muscheler, R., Otto-Bliesner, B. L., Pongratz, J., Shindell, D. T., Solanki, S. K., Steinhilber F., and Vieira, L. E. A.: Climate forcing reconstructions for use in PMIP simulations of the last millennium (v1.0), Geosci. Model Dev., 4, 33–45, 2011.
Servonnat, J., Yiou, P., Khodri, M., Swingedouw, D., and Denvil, S.: Influence of solar variability, CO2 and orbital forcing between 1000 and 1850 AD in the IPSLCM4 model, Clim. Past, 6, 445–460, 2010.
Stenchikov, G., Delworth, T. L., Ramswamy, V., Stouffer, R. J., Wittenberg, A., and Zeng, F.: Volcanic signals in oceans, J. Geophys. Res., 114, D16104, https://doi.org/10.1029/2008JD011673, 2009.
Stevens, B., Giorgetta, M., Esch, M., Mauritsen, T., Crueger, T., Rast, S., Salzmann, M., Schmidt, H., Bader, J., Block, K., Brokopf, R., Fast, I., Kinne, S., Kornblueh, L., Lohmann, U., Pincus, R., Reichler, T., and Roeckner, E.: Atmospheric component of the MPI-M Earth System Model: ECHAM6, J. Adv. Model. Earth Syst., 5, 146–172, 2013.
Svendsen, L., Hetzinger, S., Keenlyside, N., and Gao, Y. Q.: Marine-based multiproxy reconstruction of Atlantic multidecadal variability, Geophys. Res. Lett., 41, 2013GL059076, https://doi.org/10.1002/2013GL059076, 2014.
Swingedouw, D., Terray, L., Cassou, C., Voldoire, A., Salas-Melia, D., and Servonnat, J.: Natural forcing of climate during the last millennium: Fingerprint of solar variability and NAO, Clim. Dynam., 36, 1349–1364, 2011.
Swingedouw, D., Mignot, J., Labetoule, S., Guilyardi, E., and Madec, G.: Initialisation and predictability of the AMOC over the last 50 years in a climate model, Clim. Dynam., 40, 2381–2399, 2013.
Terray, L.: Evidence for multiple drivers of North Atlantic multi-decadal climate variability, Geophys. Res. Lett., 39, L19712, https://doi.org/10.1029/2012GL053046, 2012.
Terray, L. and Thual, O.: Oasis: le couplage océan-atmosphére, La Météorologie, 10, 50–61, 1995.
Trenberth, K. and Shea, D.: Atlantic hurricanes and natural variability in 2005, Geophys. Res. Lett., 33, L12704, https://doi.org/10.1029/2006GL026894, 2006.
Valcke, S., Terray, L., and Piacentini, A.: Oasis 2.4, Ocean atmosphere sea ice soil: user's guide, Tech. Rep. TR/CMGC/00/10, CERFACS, Toulouse, France, 2000.
Valcke, S., Claubel, A., Declat, D., and Terray, L.: OASIS Ocean Atmosphere Sea Ice Soil user's guide, Tech. Rep. TR/CMGC/03/69, CERFACS, Toulouse, France, 2003.
Vieira, L. and Solanki, S. K.: Evolution of the solar magnetic flux on time scales of years to millennia, Annu. Rev. Astron. Astr., 509, arXiv/0911.4396, https://doi.org/10.1051/00046361/200913276, 2009.
Vieira, L., Solanki, S. K., Krivova, N. A., and Usoskin, I.: Evolution of the solar irradiance during the Holocene, Astron. Astroph., 531, A6, https://doi.org/10.1051/0004-6361/201015843, 2011.
Wold, C.: Cenozoic sediment accumulation on drifts in the northern North Atlantic, Paleoceanography, 9, 917–941, 1994.
Zanchettin, D., Timmreck, C., Graf, H. F., Rubino, A., Lorenz, S., Lohmann, K., Krüger, K., and Jungclaus, J. H.: Bi-decadal variability excited in the coupled ocean–atmosphere system by strong tropical volcanic eruptions, Clim. Dynam., 39, 419–444, 2012.
Zanchettin, D., Rubino, A., Matei, D., Bothe, O., and Jungclaus, J. H.: Multidecadal-to-centennial SST variability in the MPI-ESM simulation ensemble for the last millennium, Clim. Dynam., 40, 1301–1318, 2013.
Zanchettin, D., Bothe, O., Müller, W. A., Bader, J., and Jungclaus, J. H.: Different flavors of the Atlantic Multidecadal Variability, Clim. Dynam., 42, 381–399, 2014.
Zhang, L. and Wang, C.: Multidecadal North Atlantic sea surface temperature and Atlantic meridional overturning circulation variability in CMIP5 historical simulations, J. Geophys. Res., 118, 5772–5791, 2013.
Zhong, Y., Miller, G. H., Otto-Bliesner, B. L., Holland, M. M., Bailey, D. A., Schneider, D. P., and Geirsdottir, A.: Centennialscale climate change from decadally-paced explosive volcanism: a couled sea ice-ocean mechanism, Clim. Dynam., 37, 2373–2387, 2011.
Short summary
We use model simulations to investigate mechanisms of similar Iceland--Scotland overflow (outflow from the Nordic seas) and North Atlantic sea surface temperature variability, suggested from palaeo-reconstructions (Mjell et al., 2015). Our results indicate the influence of Nordic Seas surface temperature on the pressure gradient across the Iceland--Scotland ridge, not a large-scale link through the meridional overturning circulation, is responsible for the (simulated) co-variability.
We use model simulations to investigate mechanisms of similar Iceland--Scotland overflow...
