Article
Meteorology & Atmospheric Sciences
Hyo-Jeong Kim, Soon-Il An, Soong-Ki Kim, Jae-Heung Park
Summary: This study aims to improve the understanding of transient thermohaline circulation responses under rapidly varying forcing and their dependence on forcing time scales. The results suggest that the Atlantic meridional overturning circulation collapse and recovery occur at higher and lower freshwater forcing values, respectively, when the forcing time scale is shorter.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Fabio Boeira Dias, Catia M. Domingues, Simon J. Marsland, Stephen R. Rintoul, Petteri Uotila, Russell Fiedler, Mauricio M. Mata, Nathaniel L. Bindoff, Abhishek Savita
Summary: The study highlights the influence of surface wind perturbations on the response of the Antarctic subpolar Southern Ocean, leading to enhanced Antarctic Bottom Water formation and accelerated global Meridional Overturning Circulation. Open Water Polynya (OWP) events are triggered by upwelling warm waters and inhibition of sea ice growth, with their availability linked to deep ocean heat reservoirs.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
David B. Bonan, Andrew F. Thompson, Emily R. Newsom, Shantong Sun, Maria Rugenstein
Summary: This study examines the response of the Atlantic meridional overturning circulation (AMOC) to an abrupt quadrupling of atmospheric carbon dioxide using a collection of GCM simulations. The simulations show consistent weakening of the AMOC during the first century, but diverse behaviors over longer time scales. The study attributes the AMOC behavior to changes in temperature and salinity in different regions, highlighting the importance of considering high-latitude freshwater changes and salinity anomalies for understanding the long-term evolution of the AMOC.
JOURNAL OF CLIMATE
(2022)
Article
Meteorology & Atmospheric Sciences
Anastasia Romanou, David Rind, Jeff Jonas, Ron Miller, Maxwell Kelley, Gary Russell, Clara Orbe, Larissa Nazarenko, Rebecca Latto, Gavin a. Schmidt
Summary: A 10-member ensemble simulation with the NASA GISS-E2-1-G climate model shows a clear bifurcation in the Atlantic meridional overturning circulation (AMOC) strength under the SSP2-4.5 extended scenario. This response is a manifestation of noise-induced bifurcation, enhanced by feedbacks, revealing the role stochastic variability may play in AMOC stability. Rating: 7/10.
JOURNAL OF CLIMATE
(2023)
Article
Meteorology & Atmospheric Sciences
Dafydd Stephenson, F. Sevellec
Summary: This study introduces an optimization framework and computational method to investigate sources of ocean uncertainty, revealing that high-frequency variations in meridional transports are mainly wind-driven, while surface buoyancy forcing is the dominant source of uncertainty at lower frequencies. Mesoscale eddies contribute the most to year-averaged quantities in the subtropical region, but their impact is significantly reduced in the subpolar region.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Anne-Sophie Fortin, Carolina O. Dufour, Timothy M. Merlis, Rym Msadek
Summary: This study investigates the response of the Atlantic meridional overturning circulation (AMOC) to increased atmospheric carbon dioxide (CO2) concentration and identifies the drivers of this response. The research finds that different representations of oceanic processes lead to significant differences in the AMOC response across climate models. The AMOC shows a reduction of similar magnitude in low and high resolutions, while a muted response is found in medium resolution. Changes in the geostrophic and eddy streamfunctions contribute differently to the AMOC decline and there is a weak connection between the deep water formation regions and the Deep Western Boundary Current in the medium resolution.
JOURNAL OF CLIMATE
(2023)
Article
Meteorology & Atmospheric Sciences
Clara Orbe, David Rind, Ron l. Miller, Larissa S. Nazarenko, Anastasia Romanou, Jeffrey Jonas, Gary l. Russell, Maxwell Kelley, Gavin A. Schmidt
Summary: Climate models project a future weakening of the AMOC, but the impacts of this on climate are uncertain. By using a unique ensemble of CMIP6 GISS ModelE (E2.1) SSP 2-4.5 integrations, we isolate the climate impacts of a weakened AMOC and find that it results in a northward shift and strengthening of the NH Hadley cell and intensification of the northern midlatitude eddy-driven jet.
JOURNAL OF CLIMATE
(2023)
Review
Multidisciplinary Sciences
Thomas W. N. Haine, Ali H. Siddiqui, Wenrui Jiang
Summary: This article reviews and synthesizes the state of knowledge on Arctic Ocean and sub-polar North Atlantic salinity variations and their causes. It also discusses the prospects to detect the emergence of Arctic anthropogenic freshening and the likely impacts on the Atlantic Meridional Overturning Circulation.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Meteorology & Atmospheric Sciences
Rui Jiang, Haijun Yang
Summary: The study found that the Rocky Mountains have a significant impact on atmospheric moisture transport between the Atlantic and Pacific Oceans, but play a trivial role in Northern Hemisphere deep-water formation.
JOURNAL OF CLIMATE
(2021)
Article
Multidisciplinary Sciences
William E. Johns, Shane Elipot, David A. Smeed, Ben Moat, Brian King, Denis L. Volkov, Ryan H. Smith
Summary: Continuous measurements of the Atlantic meridional overturning circulation (AMOC) and meridional ocean heat transport at 26.5 degrees N have been conducted since 2004. This review examines the interannual changes in AMOC and heat transport observed over nearly two decades and discusses their impacts on North Atlantic heat content.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Meteorology & Atmospheric Sciences
Oliver J. Tooth, Helen L. Johnson, Chris Wilson
Summary: The strength of the AMOC at subpolar latitudes is dominated by water mass transformation in the eastern SPNA. However, the distribution of this overturning across the individual circulation pathways of both the SPG and the Nordic seas overflows is poorly understood. Water mass transformation along the pathways of the eastern SPG accounts for 55% of the mean strength of the eastern subpolar AMOC.
JOURNAL OF CLIMATE
(2023)
Article
Meteorology & Atmospheric Sciences
D. S. Dukhovskoy, I. Yashayaev, E. P. Chassignet, P. G. Myers, G. Platov, A. Proshutinsky
Summary: The impact of increasing Greenland freshwater discharge on the subpolar North Atlantic requires decades to adjust, with long-lasting freshwater discharge leading to a non-steady-state response in the region.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Bryam Orihuela-Pinto, Agus Santoso, Matthew H. England, Andrea S. Taschetto
Summary: This study investigates the effect of an AMOC collapse on ENSO by adding freshwater in the North Atlantic in a global climate model. The results show that an AMOC collapse leads to weaker ENSO variability, with a reduction in extreme El Nino events and a shift of the ENSO pattern toward the central Pacific.
JOURNAL OF CLIMATE
(2022)
Article
Meteorology & Atmospheric Sciences
Yang Li, Haijun Yang
Summary: This study uses a single-hemisphere 4-box model to investigate the low-frequency variability of the Atlantic meridional overturning circulation (AMOC). It suggests that the AMOC exhibits a self-sustained multicentennial oscillation when an enhanced mixing mechanism is introduced in the subpolar ocean. The study also shows that stochastic freshwater forcing can excite the multicentennial oscillation. These findings suggest the presence of an intrinsic multicentennial mode in the Atlantic Ocean.
JOURNAL OF CLIMATE
(2022)
Article
Meteorology & Atmospheric Sciences
Shantong Sun, Andrew F. Thompson, Shang-Ping Xie, Shang-Min Long
Summary: The reorganization of the Atlantic meridional overturning circulation (AMOC) leads to interbasin heat transport, which redistributes heat between the Atlantic and Indo-Pacific basins. This transient response plays a key role in the global ocean heat budget, especially in a changing climate.
JOURNAL OF CLIMATE
(2022)
Article
Meteorology & Atmospheric Sciences
Leon Hermanson, Doug Smith, Melissa Seabrook, Roberto Bilbao, Francisco Doblas-Reyes, Etienne Tourigny, Vladimir Lapin, Viatcheslav V. Kharin, William J. Merryfield, Reinel Sospedra-Alfonso, Panos Athanasiadis, Dario Nicoli, Silvio Gualdi, Nick Dunstone, Rosie Eade, Adam Scaife, Mark Collier, Terence O'Kane, Vassili Kitsios, Paul Sandery, Klaus Pankatz, Barbara Frueh, Holger Pohlmann, Wolfgang Mueller, Takahito Kataoka, Hiroaki Tatebe, Masayoshi Ishii, Yukiko Imada, Tim Kruschke, Torben Koenigk, Mehdi Pasha Karami, Shuting Yang, Tian Tian, Liping Zhang, Tom Delworth, Xiaosong Yang, Fanrong Zeng, Yiguo Wang, Francois Counillon, Noel Keenlyside, Ingo Bethke, Judith Lean, Juerg Luterbacher, Rupa Kumar Kolli, Arun Kumar
Summary: As climate change accelerates, societies and climate-sensitive socioeconomic sectors need new methods to guide future adaptation efforts. Operational decadal predictions, like the ones provided by the WMO Lead Centre for Annual to Decadal Climate Predictions, can fill the gap between seasonal forecasts and climate projections. The collaboration produces skillful predictions that inform policy-makers about global climate trends and the probability of exceeding the Paris Agreement's temperature targets.
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
(2022)
Article
Meteorology & Atmospheric Sciences
J. H. Jungclaus, S. J. Lorenz, H. Schmidt, V Brovkin, N. Brueggemann, F. Chegini, T. Crueger, P. De-Vrese, V Gayler, M. A. Giorgetta, O. Gutjahr, H. Haak, S. Hagemann, M. Hanke, T. Ilyina, P. Korn, J. Kroeger, L. Linardakis, C. Mehlmann, U. Mikolajewicz, W. A. Mueller, J. E. M. S. Nabel, D. Notz, H. Pohlmann, D. A. Putrasahan, T. Raddatz, L. Ramme, R. Redler, C. H. Reick, T. Riddick, T. Sam, R. Schneck, R. Schnur, M. Schupfner, J-S Storch, F. Wachsmann, K-H Wieners, F. Ziemen, B. Stevens, J. Marotzke, M. Claussen
Summary: This work introduces the first coupled model based on the ICON framework, called ICON-ESM V1.0, and describes its tuning and performance evaluation in CMIP. The model shows good performance in atmosphere and ocean simulations, but has overall biases and problematic biases.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2022)
Article
Geosciences, Multidisciplinary
Ed Hawkins, Stephen Burt, Mark McCarthy, Conor Murphy, Catherine Ross, Mike Baldock, John Brazier, Gill Hersee, Jacqui Huntley, Richard Meats, John O'Grady, Ian Scrimgeour, Tim Silk
Summary: Recovering additional historical weather observations from known archival sources provides insights into climate change and unusual events. The UK National Meteorological Archive recently digitized over 66,000 paper sheets, containing 5.28 million hand-written monthly rainfall observations. More than 16,000 volunteer citizen scientists transcribed and quality controlled over 3.34 million observations from over 6000 locations. This data enables longer and improved reconstructions of past variations in rainfall and the study of flooding and drought.
GEOSCIENCE DATA JOURNAL
(2023)
Article
Meteorology & Atmospheric Sciences
Matthew P. Couldrey, Jonathan M. Gregory, Xiao Dong, Oluwayemi Garuba, Helmuth Haak, Aixue Hu, William J. Hurlin, Jiangbo Jin, Johann Jungclaus, Armin Koehl, Hailong Liu, Sayantani Ojha, Oleg A. Saenko, Abhishek Savita, Tatsuo Suzuki, Zipeng Yu, Laure Zanna
Summary: The effect of anthropogenic climate change in the ocean is challenging to project due to the different responses of atmosphere-ocean general circulation models (AOGCMs). This study focuses on the changes in the Atlantic Meridional Overturning Circulation (AMOC), ocean heat content (Delta OHC), and the spatial pattern of ocean dynamic sea level (Delta zeta). The results show that the weakening of AMOC is mainly caused by the North Atlantic heat flux perturbation, and further weakened by a positive coupled heat flux feedback. The AMOC decline has significant impacts on the warming of the South Atlantic-Southern Ocean interface.
Article
Geosciences, Multidisciplinary
Ed Hawkins, Lisa V. Alexander, Rob J. Allan
Summary: Millions of sub-daily sea-level pressure observations taken between 1919 and 1960 over the British and Irish Isles have been rediscovered and provide valuable data for studying long-term weather variations in the region. The data will be essential in constraining future reanalyses.
GEOSCIENCE DATA JOURNAL
(2023)
Article
Meteorology & Atmospheric Sciences
Holger Pohlmann, Sebastian Brune, Kristina Froehlich, Johann H. Jungclaus, Christine Sgoff, Johanna Baehr
Summary: We have developed a data assimilation scheme using the ICON-ESM model for operational climate predictions. The scheme includes an Ensemble Kalman Filter for the ocean component and has been applied to a retrospective prediction experiment. The assimilation successfully initializes the ocean component and shows predictability in sea surface temperature, salinity, and oceanic heat and salt contents.
Article
Environmental Sciences
Hunter C. Douglas, Luke J. Harrington, Manoj Joshi, Ed Hawkins, Laura E. Revell, David J. Frame
Summary: The CMIP6 model ensemble predicts that climate change will emerge soonest and most strongly at low latitudes, regardless of the emissions pathway taken. The models project earlier and stronger emergence under the Shared Socio-economic Pathways than the previous generation did under corresponding Representative Concentration Pathways. These changes are caused by a combination of higher effective climate sensitivity, changes to emissions pathways, and region-scale climate responses between model generations.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Meteorology & Atmospheric Sciences
Ben Harvey, Ed Hawkins, Rowan Sutton
Summary: Climate projections for the UK exhibit substantial uncertainty due to the dynamical changes of the regional atmospheric circulation. The extent of change in the North Atlantic jet and its impact on UK weather and climate are of particular importance. This article proposes the use of jet-based storylines to assess and communicate uncertainty in UK climate projections, providing a framework for evaluating a range of plausible future climate outcomes and their potential impacts. By constructing future jet storylines and evaluating their impact on UK precipitation, this approach increases confidence in projecting changes in UK precipitation associated with each storyline.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2023)
Article
Multidisciplinary Sciences
B. B. Cael, Jonah Bloch-Johnson, Paulo Ceppi, Hege-Beate Fredriksen, Philip Goodwin, Jonathan M. Gregory, Christopher J. Smith, Richard G. Williams
Summary: The climate feedback, influenced by sea surface temperature patterns, has become more negative in recent decades, resulting in concentration of warming in the western tropical Pacific. However, this phenomenon has mainly been studied in climate models. By analyzing historical records, we observed a decrease in climate feedback over the past 50 years, leading to a reduction in climate sensitivity. These findings highlight the importance of understanding and simulating this trend for reliable climate projections.
Article
Geosciences, Multidisciplinary
Praveen Teleti, Ed Hawkins, Kevin R. Wood
Summary: The number and coverage of weather observations over the oceans were greatly reduced during World War II due to trade disruptions. However, a dataset of over 630,000 records has been created by rescuing detailed hourly weather observations from the US Navy Pacific Fleet's logbook images. This dataset fills gaps in existing reconstructions and provides valuable instrumental weather observations during WW2.
GEOSCIENCE DATA JOURNAL
(2023)
Article
Meteorology & Atmospheric Sciences
Pietro Salvi, Jonathan M. Gregory, Paulo Ceppi
Summary: We investigated the time-dependence of radiative feedback by analyzing experiments using climate models with historical forcings. We found that radiative feedback is influenced by different forcing agents, primarily through cloud impact on shortwave radiation. The historical feedback driven by observed sea surface temperature change alone differs from the feedback simulated with all forcing agents. Volcanic forcing plays an important role in understanding the time-variation.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Editorial Material
Geosciences, Multidisciplinary
Flavio Lehner, Ed Hawkins, Rowan Sutton, Angeline G. Pendergrass, Frances C. Moore
Summary: Combining new constraints on socio-economic trajectories and climate system's response to emissions can significantly reduce projection uncertainties, providing more accurate information for regional climate adaptation decisions.
Article
Geosciences, Multidisciplinary
Manoj Joshi, Robert A. Hall, David P. Stevens, Ed Hawkins
Summary: The 18.6-year lunar nodal cycle has a global effect on climate, with cyclic signals observed in surface air temperature, ocean heat uptake, and mean sea level pressure. The timing of anomalies in surface air temperature and heat uptake is consistent with the global warming slowdown in the early 21st century. The lunar nodal cycle is expected to contribute negatively to global temperature in the mid-2020s, reducing uncertainty in the projected time to reach 1.5 degrees C above pre-industrial levels.
EARTH SYSTEM DYNAMICS
(2023)
Article
Geosciences, Multidisciplinary
Ed Hawkins, Philip Brohan, Samantha N. Burgess, Stephen Burt, Gilbert P. Compo, Suzanne L. Gray, Ivan D. Haigh, Hans Hersbach, Kiki Kuijjer, Oscar Martinez-Alvarado, Chesley McColl, Andrew P. Schurer, Laura Slivinski, Joanne Williams
Summary: Billions of historical climatological observations stored in archives can transform our understanding of historical climate variations, including extreme weather events, if converted from paper to digital. By rescuing and assimilating atmospheric pressure observations from February 1903, the severity of a windstorm during that time was accurately represented, with winds stronger than modern events. The combination of historical observations and modern techniques enables the reconstruction of a windstorm and storm surge over 100 years ago, improving risk assessments for extreme weather.
NATURAL HAZARDS AND EARTH SYSTEM SCIENCES
(2023)
Article
Meteorology & Atmospheric Sciences
Oleg A. Saenko, Jonathan M. Gregory, Neil F. Tandon
Summary: This study evaluates the contribution of different ocean processes to Arctic Ocean warming using an ensemble of AOGCMs in an idealized climate change experiment. The findings show that the Arctic Ocean warming is greater than the global ocean warming, but the uncertainty of Arctic Ocean warming is much larger. The import of extra heat and the large-scale barotropic ocean circulation play dominant roles in Arctic Ocean warming. The weakening of the AMOC opposes and mitigates the Arctic Ocean warming, but the magnitude of this effect varies across different models.
