Articles | Volume 3, issue 2
https://doi.org/10.5194/wcd-3-645-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-3-645-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Jun 2022
Research article |
| 15 Jun 2022
| 15 Jun 2022
Relationship between southern hemispheric jet variability and forced response: the role of the stratosphere
Philipp Breul
CORRESPONDING AUTHOR
Department of Physics, Imperial College London, London, United Kingdom
Paulo Ceppi
Department of Physics, Imperial College London, London, United Kingdom
Grantham Institute, Imperial College London, London, United Kingdom
Theodore G. Shepherd
Department of Meteorology, University of Reading, Reading, United Kingdom
Related authors
Philipp Breul, Paulo Ceppi, and Theodore G. Shepherd
Weather Clim. Dynam., 4, 39–47, https://doi.org/10.5194/wcd-4-39-2023, https://doi.org/10.5194/wcd-4-39-2023, 2023
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Accurately predicting the response of the midlatitude jet stream to climate change is very important, but models show a variety of possible scenarios. Previous work identified a relationship between climatological jet latitude and future jet shift in the southern hemispheric winter. We show that the relationship does not hold in separate sectors and propose that zonal asymmetries are the ultimate cause in the zonal mean. This questions the usefulness of the relationship.
Henrik Auestad, Clemens Spensberger, Andrea Marcheggiani, Paulo Ceppi, Thomas Spengler, and Tim Woollings
Weather Clim. Dynam., 5, 1269–1286, https://doi.org/10.5194/wcd-5-1269-2024, https://doi.org/10.5194/wcd-5-1269-2024, 2024
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Latent heating due to condensation can influence atmospheric circulation by strengthening or weakening horizontal temperature contrasts. Strong temperature contrasts intensify storms and imply the existence of strong upper tropospheric winds called jets. It remains unclear whether latent heating preferentially reinforces or abates the existing jet. We show that this disagreement is attributable to how the jet is defined, confirming that latent heating reinforces the jet.
Sebastian Sippel, Clair Barnes, Camille Cadiou, Erich Fischer, Sarah Kew, Marlene Kretschmer, Sjoukje Philip, Theodore G. Shepherd, Jitendra Singh, Robert Vautard, and Pascal Yiou
Weather Clim. Dynam., 5, 943–957, https://doi.org/10.5194/wcd-5-943-2024, https://doi.org/10.5194/wcd-5-943-2024, 2024
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Winter temperatures in central Europe have increased. But cold winters can still cause problems for energy systems, infrastructure, or human health. Here we tested whether a record-cold winter, such as the one observed in 1963 over central Europe, could still occur despite climate change. The answer is yes: it is possible, but it is very unlikely. Our results rely on climate model simulations and statistical rare event analysis. In conclusion, society must be prepared for such cold winters.
Sarah Wilson Kemsley, Paulo Ceppi, Hendrik Andersen, Jan Cermak, Philip Stier, and Peer Nowack
Atmos. Chem. Phys., 24, 8295–8316, https://doi.org/10.5194/acp-24-8295-2024, https://doi.org/10.5194/acp-24-8295-2024, 2024
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Aiming to inform parameter selection for future observational constraint analyses, we incorporate five candidate meteorological drivers specifically targeting high clouds into a cloud controlling factor framework within a range of spatial domain sizes. We find a discrepancy between optimal domain size for predicting locally and globally aggregated cloud radiative anomalies and identify upper-tropospheric static stability as an important high-cloud controlling factor.
Wilson C. H. Chan, Nigel W. Arnell, Geoff Darch, Katie Facer-Childs, Theodore G. Shepherd, and Maliko Tanguy
Nat. Hazards Earth Syst. Sci., 24, 1065–1078, https://doi.org/10.5194/nhess-24-1065-2024, https://doi.org/10.5194/nhess-24-1065-2024, 2024
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The most recent drought in the UK was declared in summer 2022. We pooled a large sample of plausible winters from seasonal hindcasts and grouped them into four clusters based on their atmospheric circulation configurations. Drought storylines representative of what the drought could have looked like if winter 2022/23 resembled each winter circulation storyline were created to explore counterfactuals of how bad the 2022 drought could have been over winter 2022/23 and beyond.
Philip Goodwin, Richard Williams, Paulo Ceppi, and B. B. Cael
EGUsphere, https://doi.org/10.5194/egusphere-2023-2307, https://doi.org/10.5194/egusphere-2023-2307, 2023
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Climate feedbacks are normally evaluated by considering the change over time for Earth's energy balance and surface temperatures in the climate system. However, we only have around 1 degree Celsius of temperature change to utilise. Here, climate feedbacks are instead evaluated from the change in latitude of Earth's energy balance and surface temperatures, where we have around 70 degrees Celsius of temperature change to utilise.
Philipp Breul, Paulo Ceppi, and Theodore G. Shepherd
Weather Clim. Dynam., 4, 39–47, https://doi.org/10.5194/wcd-4-39-2023, https://doi.org/10.5194/wcd-4-39-2023, 2023
Short summary
Short summary
Accurately predicting the response of the midlatitude jet stream to climate change is very important, but models show a variety of possible scenarios. Previous work identified a relationship between climatological jet latitude and future jet shift in the southern hemispheric winter. We show that the relationship does not hold in separate sectors and propose that zonal asymmetries are the ultimate cause in the zonal mean. This questions the usefulness of the relationship.
Wilson C. H. Chan, Theodore G. Shepherd, Katie Facer-Childs, Geoff Darch, and Nigel W. Arnell
Hydrol. Earth Syst. Sci., 26, 1755–1777, https://doi.org/10.5194/hess-26-1755-2022, https://doi.org/10.5194/hess-26-1755-2022, 2022
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We select the 2010–2012 UK drought and investigate an alternative unfolding of the drought from changes to its attributes. We created storylines of drier preconditions, alternative seasonal contributions, a third dry winter, and climate change. Storylines of the 2010–2012 drought show alternative situations that could have resulted in worse conditions than observed. Event-based storylines exploring plausible situations are used that may lead to high impacts and help stress test existing systems.
Beatriz M. Monge-Sanz, Alessio Bozzo, Nicholas Byrne, Martyn P. Chipperfield, Michail Diamantakis, Johannes Flemming, Lesley J. Gray, Robin J. Hogan, Luke Jones, Linus Magnusson, Inna Polichtchouk, Theodore G. Shepherd, Nils Wedi, and Antje Weisheimer
Atmos. Chem. Phys., 22, 4277–4302, https://doi.org/10.5194/acp-22-4277-2022, https://doi.org/10.5194/acp-22-4277-2022, 2022
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The stratosphere is emerging as one of the keys to improve tropospheric weather and climate predictions. This study provides evidence of the role the stratospheric ozone layer plays in improving weather predictions at different timescales. Using a new ozone modelling approach suitable for high-resolution global models that provide operational forecasts from days to seasons, we find significant improvements in stratospheric meteorological fields and stratosphere–troposphere coupling.
Adam A. Scaife, Mark P. Baldwin, Amy H. Butler, Andrew J. Charlton-Perez, Daniela I. V. Domeisen, Chaim I. Garfinkel, Steven C. Hardiman, Peter Haynes, Alexey Yu Karpechko, Eun-Pa Lim, Shunsuke Noguchi, Judith Perlwitz, Lorenzo Polvani, Jadwiga H. Richter, John Scinocca, Michael Sigmond, Theodore G. Shepherd, Seok-Woo Son, and David W. J. Thompson
Atmos. Chem. Phys., 22, 2601–2623, https://doi.org/10.5194/acp-22-2601-2022, https://doi.org/10.5194/acp-22-2601-2022, 2022
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Great progress has been made in computer modelling and simulation of the whole climate system, including the stratosphere. Since the late 20th century we also gained a much clearer understanding of how the stratosphere interacts with the lower atmosphere. The latest generation of numerical prediction systems now explicitly represents the stratosphere and its interaction with surface climate, and here we review its role in long-range predictions and projections from weeks to decades ahead.
Linda van Garderen, Frauke Feser, and Theodore G. Shepherd
Nat. Hazards Earth Syst. Sci., 21, 171–186, https://doi.org/10.5194/nhess-21-171-2021, https://doi.org/10.5194/nhess-21-171-2021, 2021
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The storyline method is used to quantify the effect of climate change on a particular extreme weather event using a global atmospheric model by simulating the event with and without climate change. We present the method and its successful application for the climate change signals of the European 2003 and the Russian 2010 heatwaves.
Marlene Kretschmer, Giuseppe Zappa, and Theodore G. Shepherd
Weather Clim. Dynam., 1, 715–730, https://doi.org/10.5194/wcd-1-715-2020, https://doi.org/10.5194/wcd-1-715-2020, 2020
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The winds in the polar stratosphere affect the weather in the mid-latitudes, making it important to understand potential changes in response to global warming. However, climate model projections disagree on how this so-called polar vortex will change in the future. Here we show that sea ice loss in the Barents and Kara (BK) seas plays a central role in this. The time when the BK seas become ice-free differs between models, which explains some of the disagreement regarding vortex projections.
Emanuele Bevacqua, Michalis I. Vousdoukas, Theodore G. Shepherd, and Mathieu Vrac
Nat. Hazards Earth Syst. Sci., 20, 1765–1782, https://doi.org/10.5194/nhess-20-1765-2020, https://doi.org/10.5194/nhess-20-1765-2020, 2020
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Coastal compound flooding (CF), caused by interacting storm surges and high water runoff, is typically studied based on concurring storm surge extremes with either precipitation or river discharge extremes. Globally, these two approaches show similar CF spatial patterns, especially where the CF potential is the highest. Deviations between the two approaches increase with the catchment size. The precipitation-based analysis allows for considering
local-rainfall-driven CF and CF in small rivers.
C. McLandress, T. G. Shepherd, A. I. Jonsson, T. von Clarmann, and B. Funke
Atmos. Chem. Phys., 15, 9271–9284, https://doi.org/10.5194/acp-15-9271-2015, https://doi.org/10.5194/acp-15-9271-2015, 2015
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This is the first paper of its kind describing a method for merging the long-term satellite records of global stratospheric temperature from SSU and AMSU to yield a continuous data set from 1979 to present (and beyond). Since global-mean stratospheric temperature is close to radiative equilibrium, our "extended" SSU data set is an important climate record for the detection and attribution of anthropogenic influence.
V. Matthias, T. G. Shepherd, P. Hoffmann, and M. Rapp
Ann. Geophys., 33, 199–206, https://doi.org/10.5194/angeo-33-199-2015, https://doi.org/10.5194/angeo-33-199-2015, 2015
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A vertical coupling process in the northern high-latitude middle atmosphere has been identified during the equinox transitions, which we call the “hiccup” and which acts like a “mini sudden stratospheric warming (SSW)”. We study the average characteristics of the hiccup based on a composite analysis using a nudged model. A comparison of the average characteristics of hiccups and SSWs shows both similarities and differences between the two vertical coupling processes.
C. McLandress, D. A. Plummer, and T. G. Shepherd
Atmos. Chem. Phys., 14, 1547–1555, https://doi.org/10.5194/acp-14-1547-2014, https://doi.org/10.5194/acp-14-1547-2014, 2014
Related subject area
Role of atmospheric dynamics in climate change projections
Could an extremely cold central European winter such as 1963 happen again despite climate change?
Impact of climate change on persistent cold-air pools in an alpine valley during the 21st century
Future changes in North Atlantic winter cyclones in CESM-LE – Part 2: A Lagrangian analysis
Atmospheric bias teleconnections in boreal winter associated with systematic sea surface temperature errors in the tropical Indian Ocean
The relationship between extra-tropical cyclone intensity and precipitation in idealised current and future climates
Future changes in the mean and variability of extreme rainfall indices over the Guinea coast and role of the Atlantic equatorial mode
Warm conveyor belts in present-day and future climate simulations – Part 1: Climatology and impacts
Warm conveyor belts in present-day and future climate simulations – Part 2: Role of potential vorticity production for cyclone intensification
A climate-change attribution retrospective of some impactful weather extremes of 2021
The response of tropical cyclone intensity to changes in environmental temperature
Storm track response to uniform global warming downstream of an idealized sea surface temperature front
Future changes in North Atlantic winter cyclones in CESM-LE – Part 1: Cyclone intensity, potential vorticity anomalies, and horizontal wind speed
Impact of climate change on wintertime European atmospheric blocking
Twenty-first-century Southern Hemisphere impacts of ozone recovery and climate change from the stratosphere to the ocean
Future summer warming pattern under climate change is affected by lapse-rate changes
The importance of horizontal model resolution on simulated precipitation in Europe – from global to regional models
Future wintertime meridional wind trends through the lens of subseasonal teleconnections
Decomposing the response of the stratospheric Brewer–Dobson circulation to an abrupt quadrupling in CO2
The substructure of extremely hot summers in the Northern Hemisphere
Sebastian Sippel, Clair Barnes, Camille Cadiou, Erich Fischer, Sarah Kew, Marlene Kretschmer, Sjoukje Philip, Theodore G. Shepherd, Jitendra Singh, Robert Vautard, and Pascal Yiou
Weather Clim. Dynam., 5, 943–957, https://doi.org/10.5194/wcd-5-943-2024, https://doi.org/10.5194/wcd-5-943-2024, 2024
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Short summary
Winter temperatures in central Europe have increased. But cold winters can still cause problems for energy systems, infrastructure, or human health. Here we tested whether a record-cold winter, such as the one observed in 1963 over central Europe, could still occur despite climate change. The answer is yes: it is possible, but it is very unlikely. Our results rely on climate model simulations and statistical rare event analysis. In conclusion, society must be prepared for such cold winters.
Sara Bacer, Julien Beaumet, Martin Ménégoz, Hubert Gallée, Enzo Le Bouëdec, and Chantal Staquet
Weather Clim. Dynam., 5, 211–229, https://doi.org/10.5194/wcd-5-211-2024, https://doi.org/10.5194/wcd-5-211-2024, 2024
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A model chain is used to downscale outputs from a climate model to the Grenoble valley atmosphere over the 21st century in order to study the impact of climate change on persistent cold-air pool episodes. We find that the atmosphere in the Grenoble valleys during these episodes tends to be slightly less stable in the future under the SSP5–8.5 scenario, and statistically unchanged under the SSP2–4.5 scenario but that very stable persistent cold-air pool episodes can still form.
Edgar Dolores-Tesillos and Stephan Pfahl
Weather Clim. Dynam., 5, 163–179, https://doi.org/10.5194/wcd-5-163-2024, https://doi.org/10.5194/wcd-5-163-2024, 2024
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In a warmer climate, the winter extratropical cyclones over the North Atlantic basin are expected to have a larger footprint of strong winds. Dynamical changes at different altitudes are responsible for these wind changes. Based on backward trajectories using the CESM-LE simulations, we show that the diabatic processes gain relevance as the planet warms. For instance, changes in the radiative processes will play an important role in the upper-level cyclone dynamics.
Yuan-Bing Zhao, Nedjeljka Žagar, Frank Lunkeit, and Richard Blender
Weather Clim. Dynam., 4, 833–852, https://doi.org/10.5194/wcd-4-833-2023, https://doi.org/10.5194/wcd-4-833-2023, 2023
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Coupled climate models have significant biases in the tropical Indian Ocean (TIO) sea surface temperature (SST). Our study shows that the TIO SST biases can affect the simulated global atmospheric circulation and its spatio-temporal variability on large scales. The response of the spatial variability is related to the amplitude or phase of the circulation bias, depending on the flow regime and spatial scale, while the response of the interannual variability depends on the sign of the SST bias.
Victoria A. Sinclair and Jennifer L. Catto
Weather Clim. Dynam., 4, 567–589, https://doi.org/10.5194/wcd-4-567-2023, https://doi.org/10.5194/wcd-4-567-2023, 2023
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We studied the relationship between the strength of mid-latitude cyclones and their precipitation, how this may change in the future, and whether it depends of the type of cyclone. The relationship between cyclone strength and precipitation increases in warmer climates and depends strongly on the type of cyclone. For some cyclone types there is no relation between cyclone strength and precipitation. For all cyclone types, precipitation increases with uniform warming and polar amplification.
Koffi Worou, Thierry Fichefet, and Hugues Goosse
Weather Clim. Dynam., 4, 511–530, https://doi.org/10.5194/wcd-4-511-2023, https://doi.org/10.5194/wcd-4-511-2023, 2023
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The Atlantic equatorial mode (AEM) of variability is partly responsible for the year-to-year rainfall variability over the Guinea coast. We used the current climate models to explore the present-day and future links between the AEM and the extreme rainfall indices over the Guinea coast. Under future global warming, the total variability of the extreme rainfall indices increases over the Guinea coast. However, the future impact of the AEM on extreme rainfall events decreases over the region.
Hanna Joos, Michael Sprenger, Hanin Binder, Urs Beyerle, and Heini Wernli
Weather Clim. Dynam., 4, 133–155, https://doi.org/10.5194/wcd-4-133-2023, https://doi.org/10.5194/wcd-4-133-2023, 2023
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Warm conveyor belts (WCBs) are strongly ascending, cloud- and precipitation-forming airstreams in extratropical cyclones. In this study we assess their representation in a climate simulation and their changes under global warming. They become moister, become more intense, and reach higher altitudes in a future climate, implying that they potentially have an increased impact on the mid-latitude flow.
Hanin Binder, Hanna Joos, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 4, 19–37, https://doi.org/10.5194/wcd-4-19-2023, https://doi.org/10.5194/wcd-4-19-2023, 2023
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Warm conveyor belts (WCBs) are the main cloud- and precipitation-producing airstreams in extratropical cyclones. The latent heat release that occurs during cloud formation often contributes to the intensification of the associated cyclone. Based on the Community Earth System Model Large Ensemble coupled climate simulations, we show that WCBs and associated latent heating will become stronger in a future climate and be even more important for explosive cyclone intensification than in the present.
Davide Faranda, Stella Bourdin, Mireia Ginesta, Meriem Krouma, Robin Noyelle, Flavio Pons, Pascal Yiou, and Gabriele Messori
Weather Clim. Dynam., 3, 1311–1340, https://doi.org/10.5194/wcd-3-1311-2022, https://doi.org/10.5194/wcd-3-1311-2022, 2022
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We analyze the atmospheric circulation leading to impactful extreme events for the calendar year 2021 such as the Storm Filomena, Westphalia floods, Hurricane Ida and Medicane Apollo. For some of the events, we find that climate change has contributed to their occurrence or enhanced their intensity; for other events, we find that they are unprecedented. Our approach underscores the importance of considering changes in the atmospheric circulation when performing attribution studies.
James M. Done, Gary M. Lackmann, and Andreas F. Prein
Weather Clim. Dynam., 3, 693–711, https://doi.org/10.5194/wcd-3-693-2022, https://doi.org/10.5194/wcd-3-693-2022, 2022
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We know that warm oceans generally favour tropical cyclones (TCs). Less is known about the role of air temperature above the oceans extending into the lower stratosphere. Our global analysis of historical records and computer simulations suggests that TCs strengthen in response to historical temperature change while also being influenced by other environmental factors. Ocean warming drives much of the strengthening, with relatively small contributions from temperature changes aloft.
Sebastian Schemm, Lukas Papritz, and Gwendal Rivière
Weather Clim. Dynam., 3, 601–623, https://doi.org/10.5194/wcd-3-601-2022, https://doi.org/10.5194/wcd-3-601-2022, 2022
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Much of the change in our daily weather patterns is due to the development and intensification of extratropical cyclones. The response of these systems to climate change is an important topic of ongoing research. This study is the first to reproduce the changes in the North Atlantic circulation and extratropical cyclone characteristics found in fully coupled Earth system models under high-CO2 scenarios, but in an idealized, reduced-complexity simulation with uniform warming.
Edgar Dolores-Tesillos, Franziska Teubler, and Stephan Pfahl
Weather Clim. Dynam., 3, 429–448, https://doi.org/10.5194/wcd-3-429-2022, https://doi.org/10.5194/wcd-3-429-2022, 2022
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Strong winds caused by extratropical cyclones represent a costly hazard for European countries. Here, based on CESM-LENS coupled climate simulations, we show that future changes of such strong winds are characterized by an increased magnitude and extended footprint southeast of the cyclone center. This intensification is related to a combination of increased diabatic heating and changes in upper-level wave dynamics.
Sara Bacer, Fatima Jomaa, Julien Beaumet, Hubert Gallée, Enzo Le Bouëdec, Martin Ménégoz, and Chantal Staquet
Weather Clim. Dynam., 3, 377–389, https://doi.org/10.5194/wcd-3-377-2022, https://doi.org/10.5194/wcd-3-377-2022, 2022
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We study the impact of climate change on wintertime atmospheric blocking over Europe. We focus on the frequency, duration, and size of blocking events. The blocking events are identified via the weather type decomposition methodology. We find that blocking frequency, duration, and size are mostly stationary over the 21st century. Additionally, we compare the blocking size results with the size of the blocking events identified via a different approach using a blocking index.
Ioana Ivanciu, Katja Matthes, Arne Biastoch, Sebastian Wahl, and Jan Harlaß
Weather Clim. Dynam., 3, 139–171, https://doi.org/10.5194/wcd-3-139-2022, https://doi.org/10.5194/wcd-3-139-2022, 2022
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Greenhouse gas concentrations continue to increase, while the Antarctic ozone hole is expected to recover during the twenty-first century. We separate the effects of ozone recovery and of greenhouse gases on the Southern Hemisphere atmospheric and oceanic circulation, and we find that ozone recovery is generally reducing the impact of greenhouse gases, with the exception of certain regions of the stratosphere during spring, where the two effects reinforce each other.
Roman Brogli, Silje Lund Sørland, Nico Kröner, and Christoph Schär
Weather Clim. Dynam., 2, 1093–1110, https://doi.org/10.5194/wcd-2-1093-2021, https://doi.org/10.5194/wcd-2-1093-2021, 2021
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In a warmer future climate, climate simulations predict that some land areas will experience excessive warming during summer. We show that the excessive summer warming is related to the vertical distribution of warming within the atmosphere. In regions characterized by excessive warming, much of the warming occurs close to the surface. In other regions, most of the warming is redistributed to higher levels in the atmosphere, which weakens the surface warming.
Gustav Strandberg and Petter Lind
Weather Clim. Dynam., 2, 181–204, https://doi.org/10.5194/wcd-2-181-2021, https://doi.org/10.5194/wcd-2-181-2021, 2021
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Precipitation is a key climate variable with a large impact on society but also difficult to simulate as it depends largely on temporal and spatial scales. We look here at the effect of model resolution on precipitation in Europe, from coarse-scale global model to small-scale regional models. Higher resolution improves simulated precipitation generally, but individual models may over- or underestimate precipitation even at higher resolution.
Dor Sandler and Nili Harnik
Weather Clim. Dynam., 1, 427–443, https://doi.org/10.5194/wcd-1-427-2020, https://doi.org/10.5194/wcd-1-427-2020, 2020
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The circumglobal teleconnection pattern (CTP) is a wavy pattern of wintertime midlatitude subseasonal flow. It is also linked to various extreme weather events. The CTP is predicted to play a prominent role in future climate. We find that for future projections, most CMIP5 models predict that the CTP will develop a
preferredphase. Our work establishes that the CTP-like climate change signature is in fact comprised of several regional effects, partly due to shifts in CTP phase distributions.
Andreas Chrysanthou, Amanda C. Maycock, and Martyn P. Chipperfield
Weather Clim. Dynam., 1, 155–174, https://doi.org/10.5194/wcd-1-155-2020, https://doi.org/10.5194/wcd-1-155-2020, 2020
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We perform 50-year-long time-slice experiments using the Met Office HadGEM3 global climate model in order to decompose the Brewer–Dobson circulation (BDC) response to an abrupt quadrupling of CO2 in three distinct components, (a) the rapid adjustment, associated with CO2 radiative effects; (b) a global uniform sea surface temperature warming; and (c) sea surface temperature patterns. This demonstrates a potential for fast and slow timescales of the response of the BDC to greenhouse gas forcing.
Matthias Röthlisberger, Michael Sprenger, Emmanouil Flaounas, Urs Beyerle, and Heini Wernli
Weather Clim. Dynam., 1, 45–62, https://doi.org/10.5194/wcd-1-45-2020, https://doi.org/10.5194/wcd-1-45-2020, 2020
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In this study we quantify how much the coldest, middle and hottest third of all days during extremely hot summers contribute to their respective seasonal mean anomaly. This
extreme-summer substructurevaries substantially across the Northern Hemisphere and is directly related to the local physical drivers of extreme summers. Furthermore, comparing re-analysis (i.e. measurement-based) and climate model extreme-summer substructures reveals a remarkable level of agreement.
Cited articles
Barnes, E. A. and Hartmann, D. L.: Testing a Theory for the Effect of Latitude on the Persistence of Eddy-Driven Jets Using CMIP3 Simulations, Geophys. Res. Lett., 37, L15801, https://doi.org/10.1029/2010GL044144, 2010. a, b, c
Barnes, E. A. and Polvani, L.: Response of the Midlatitude Jets, and of
Their Variability, to Increased Greenhouse Gases in the CMIP5
Models, J. Climate, 26, 7117–7135, https://doi.org/10.1175/JCLI-D-12-00536.1, 2013. a
Barnes, E. A. and Thompson, D. W. J.: Comparing the Roles of Barotropic versus Baroclinic Feedbacks in the Atmosphere's Response to Mechanical Forcing, J. Atmos. Sci., 71, 177–194,
https://doi.org/10.1175/JAS-D-13-070.1, 2014. a, b, c
Barsugli, J. J. and Battisti, D. S.: The Basic Effects of Atmosphere – Ocean Thermal Coupling on Midlatitude Variability, J. Atmos. Sci., 55, 477–493, https://doi.org/10.1175/1520-0469(1998)055<0477:TBEOAO>2.0.CO;2, 1998. a
Breul, P.: WCD_2021-78_Code, figshare [code], https://doi.org/10.6084/m9.figshare.20051258.v1, 2022a. a
Breul, P.: Data, figshare [data set], https://doi.org/10.6084/m9.figshare.20055467.v1, 2022b. a
Byrne, N. J., Shepherd, T. G., and Polichtchouk, I.: Subseasonal-to-Seasonal Predictability of the Southern Hemisphere Eddy-Driven Jet During Austral Spring and Early Summer, J. Geophys. Res.-Atmos., 124, 6841–6855, https://doi.org/10.1029/2018JD030173, 2019. a
Ceppi, P. and Shepherd, T. G.: The Role of the Stratospheric Polar Vortex for the Austral Jet Response to Greenhouse Gas Forcing, Geophys. Res. Lett., 46, 6972–6979, https://doi.org/10.1029/2019GL082883, 2019. a, b, c
Ceppi, P., Zelinka, M. D., and Hartmann, D. L.: The Response of the Southern Hemispheric Eddy-Driven Jet to Future Changes in Shortwave Radiation in CMIP5, Geophys. Res. Lett., 41, 3244–3250,
https://doi.org/10.1002/2014GL060043, 2014. a
Cooper, F. C. and Haynes, P. H.: Climate Sensitivity via a Nonparametric
Fluctuation–Dissipation Theorem, J. Atmos. Sci., 68, 937–953, https://doi.org/10.1175/2010JAS3633.1, 2011. a, b
Cooper, F. C., Esler, J. G., and Haynes, P. H.: Estimation of the local response to a forcing in a high dimensional system using the fluctuation-dissipation theorem, Nonlin. Processes Geophys., 20, 239–248, https://doi.org/10.5194/npg-20-239-2013, 2013. a
Curtis, P. E., Ceppi, P., and Zappa, G.: Role of the Mean State for the Southern Hemispheric Jet Stream Response to CO2 Forcing in CMIP6 Models, Environ. Res. Lett., 15, 064011, https://doi.org/10.1088/1748-9326/ab8331, 2020. a
Fuchs, D., Sherwood, S., and Hernandez, D.: An Exploration of Multivariate Fluctuation Dissipation Operators and Their Response to Sea Surface Temperature Perturbations, J. Atmos. Sci., 72, 472–486, https://doi.org/10.1175/JAS-D-14-0077.1, 2015. a, b, c
Gerber, E. P., Polvani, L. M., and Ancukiewicz, D.: Annular Mode Time Scales in the Intergovernmental Panel on Climate Change Fourth Assessment Report Models, Geophys. Res. Lett., 35, L22707, https://doi.org/10.1029/2008GL035712, 2008a. a, b
Gerber, E. P., Voronin, S., and Polvani, L. M.: Testing the Annular Mode Autocorrelation Time Scale in Simple Atmospheric General Circulation Models, Mon. Weather Rev., 136, 1523–1536, https://doi.org/10.1175/2007MWR2211.1, 2008b. a
Gerber, E. P., Baldwin, M. P., Akiyoshi, H., Austin, J., Bekki, S., Braesicke, P., Butchart, N., Chipperfield, M., Dameris, M., Dhomse, S., Frith, S. M., Garcia, R. R., Garny, H., Gettelman, A., Hardiman, S. C., Karpechko, A., Marchand, M., Morgenstern, O., Nielsen, J. E., Pawson, S., Peter, T., Plummer, D. A., Pyle, J. A., Rozanov, E., Scinocca, J. F., Shepherd, T. G., and Smale, D.: Stratosphere-Troposphere Coupling and Annular Mode Variability in Chemistry-Climate Models, J. Geophys. Res.-Atmos., 115, D00M06, https://doi.org/10.1029/2009JD013770, 2010. a, b
Gritsun, A. and Branstator, G.: Numerical aspects of applying the fluctuation dissipation theorem to study climate system sensitivity to external forcings, Russ. J. Numer. Anal. M., 31, 339–354, https://doi.org/10.1515/rnam-2016-0032, 2016. a, b
Harvey, B. J., Shaffrey, L. C., and Woollings, T. J.: Equator-to-Pole
Temperature Differences and the Extra-Tropical Storm Track Responses of the
CMIP5 Climate Models, Clim. Dynam., 43, 1171–1182,
https://doi.org/10.1007/s00382-013-1883-9, 2014. a
Hassanzadeh, P. and Kuang, Z.: The Linear Response Function of an Idealized Atmosphere. Part II: Implications for the Practical Use of the Fluctuation–Dissipation Theorem and the Role of Operator’s Nonnormality, J. Atmos. Sci., 73, 3441–3452, https://doi.org/10.1175/JAS-D-16-0099.1, 2016. a, b, c, d
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., Chiara, G. D., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 Global Reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020. a
Kretschmer, M., Adams, S. V., Arribas, A., Prudden, R., Robinson, N., Saggioro, E., and Shepherd, T. G.: Quantifying Causal Pathways of
Teleconnections, B. Am. Meteorol. Soc., 102,
E2247–E2263, https://doi.org/10.1175/BAMS-D-20-0117.1, 2021. a
Leith, C. E.: Climate Response and Fluctuation Dissipation, J. Atmos. Sci., 32, 2022–2026, https://doi.org/10.1175/1520-0469(1975)032<2022:CRAFD>2.0.CO;2, 1975. a, b
Lutsko, N. J., Held, I. M., and Zurita-Gotor, P.: Applying the Fluctuation–Dissipation Theorem to a Two-Layer Model of Quasigeostrophic Turbulence, J. Atmos. Sci., 72, 3161–3177, https://doi.org/10.1175/JAS-D-14-0356.1, 2015. a
Majda, A. J., Gershgorin, B., and Yuan, Y.: Low-Frequency Climate Response and Fluctuation–Dissipation Theorems: Theory and Practice, J. Atmos. Sci., 67, 1186–1201, https://doi.org/10.1175/2009JAS3264.1, 2010. a, b, c
Ring, M. J. and Plumb, R. A.: The Response of a Simplified GCM to Axisymmetric Forcings: Applicability of the Fluctuation–Dissipation Theorem, J. Atmos. Sci., 65, 3880–3898, https://doi.org/10.1175/2008JAS2773.1, 2008. a, b, c, d
Shepherd, T. G.: Atmospheric Circulation as a Source of Uncertainty in Climate Change Projections, Nat. Geosci., 7, 703–708, https://doi.org/10.1038/ngeo2253, 2014. a
Sheshadri, A., Plumb, R. A., Lindgren, E. A., and Domeisen, D. I. V.: The Vertical Structure of Annular Modes, J. Atmos. Sci., 75, 3507–3519, https://doi.org/10.1175/JAS-D-17-0399.1, 2018. a
Simpson, I. R. and Polvani, L. M.: Revisiting the Relationship between Jet Position, Forced Response, and Annular Mode Variability in the Southern Midlatitudes: SH Jet Latitudes, Jet Shifts and the SAM, Geophys. Res. Lett., 43, 2896–2903, https://doi.org/10.1002/2016GL067989, 2016. a, b, c, d, e, f, g, h
Simpson, I. R., Shepherd, T. G., Hitchcock, P., and Scinocca, J. F.: Southern Annular Mode Dynamics in Observations and Models. Part II: Eddy Feedbacks, J. Climate, 26, 5220–5241, https://doi.org/10.1175/JCLI-D-12-00495.1, 2013. a
Vallis, G. K., Gerber, E. P., Kushner, P. J., and Cash, B. A.: A Mechanism and Simple Dynamical Model of the North Atlantic Oscillation and Annular Modes, J. Atmos. Sci., 61, 264–280,
https://doi.org/10.1175/1520-0469(2004)061<0264:AMASDM>2.0.CO;2, 2004. a
Wilcox, L. J. and Charlton-Perez, A. J.: Final Warming of the Southern Hemisphere Polar Vortex in High- and Low-Top CMIP5 Models, J. Geophys. Res.-Atmos., 118, 2535–2546, https://doi.org/10.1002/jgrd.50254, 2013. a
Short summary
Understanding how the mid-latitude jet stream will respond to a changing climate is highly important. Unfortunately, climate models predict a wide variety of possible responses. Theoretical frameworks can link an internal jet variability timescale to its response. However, we show that stratospheric influence approximately doubles the internal timescale, inflating predicted responses. We demonstrate an approach to account for the stratospheric influence and recover correct response predictions.
Understanding how the mid-latitude jet stream will respond to a changing climate is highly...
