WCD - recent papers

WCD Ideas: hydrologically driven throughflow in the coupled ocean–atmosphere system

2026-07-08T19:09:42+02:00

WCD Ideas: hydrologically driven throughflow in the coupled ocean–atmosphere system
Andrew S. Kowalski
Weather Clim. Dynam., 7, 1211–1217, https://doi.org/10.5194/wcd-7-1211-2026, 2026
Textbooks describe the atmosphere’s north–south motion as closed circulation cells. This study shows that the water cycle also drives a subtle one-way flow of air, moving it from the humidified subtropics toward regions dried by rain and condensation. This hidden transport helps explain gradients of inert gases and suggests that large-scale atmospheric circulation may be more open than commonly assumed.

A regime-based diagnosis of transition probabilities and changes in frequency and intensity of Indian Summer Monsoon rainfall

2026-07-07T19:09:42+02:00

A regime-based diagnosis of transition probabilities and changes in frequency and intensity of Indian Summer Monsoon rainfall
Bhupendra A. Raut, Aditi Deshpande, Devyani Kamble, Sandip Ingle, Parmeshwar Naik, Shwetal Walde, P. Pradeep Kumar, and Purnendranath Sen
Weather Clim. Dynam., 7, 1173–1188, https://doi.org/10.5194/wcd-7-1173-2026, 2026
We present an unsupervised clustering methodology and post-clustering analysis framework that identifies recurring monsoon rainfall patterns and quantifies their transitions. Analysis reveals breaks are prolonged while monsoon depression are transient. The decomposition of frequency and intensity changes quantifies their contributions in long-term rainfall changes.

The October 2024 extreme precipitation event over Valencia: storyline attribution of the synoptic-scale thermodynamic drivers

2026-07-07T19:09:42+02:00

The October 2024 extreme precipitation event over Valencia: storyline attribution of the synoptic-scale thermodynamic drivers
Diego A. Campos, Katherine Grayson, Ramiro I. Saurral, Sebastian Beyer, Amal John, Matías Olmo, and Francisco Doblas-Reyes
Weather Clim. Dynam., 7, 1153–1171, https://doi.org/10.5194/wcd-7-1153-2026, 2026
Human-caused warming intensified the late October 2024 Valencia extreme precipitation event. Using storyline simulations, we compared today’s climate with a cooler past climate while keeping the synoptic weather pattern the same. Warmer air and sea temperatures increased moisture, instability, and rainfall, showing that climate change amplified an already extreme storm.

Curved atmospheric rivers and their moisture remnants: a new detection tool for Antarctica

2026-07-07T19:09:42+02:00

Curved atmospheric rivers and their moisture remnants: a new detection tool for Antarctica
Victoire Buffet, Vincent Favier, Benjamin Pohl, and Jonathan D. Wille
Weather Clim. Dynam., 7, 1189–1210, https://doi.org/10.5194/wcd-7-1189-2026, 2026
We improve the detection of long corridors of intense moisture transport, known as atmospheric rivers, that affect Antarctica. Our new method can track these rivers even when they curve, cross the South Pole, or break into smaller parts. We show that they cause even more heavy snowfall and warm weather on the continent than previously thought, clarifying their role in shaping Antarctic climate and ice loss.

Distinct bias structures for extratropical cyclones with strong or weak diabatic heating

2026-07-06T19:09:42+02:00

Distinct bias structures for extratropical cyclones with strong or weak diabatic heating
Qidi Yu, Clemens Spensberger, Linus Magnusson, and Thomas Spengler
Weather Clim. Dynam., 7, 1117–1131, https://doi.org/10.5194/wcd-7-1117-2026, 2026
Forecast biases of winter extratropical cyclones are quantified by varying diabatic heating intensity. A southwest shift and underestimated intensity are found in the strong heating group. The weaker heating group mainly shows an intensity bias. Specific biases are identified for wind, moisture, temperature, and upper-level circulation fields. Findings highlight that representing moist processes and their interaction with atmospheric dynamics is a key area for future model developments.

Revisiting the surface impacts of the QBO in the Large Ensemble Single Forcing MIP simulations: are teleconnections still too weak?

2026-07-06T19:09:42+02:00

Revisiting the surface impacts of the QBO in the Large Ensemble Single Forcing MIP simulations: are teleconnections still too weak?
Chaim I. Garfinkel, David Avisar, Scott M. Osprey, Doug Smith, Jian Rao, and Jonathon S. Wright
Weather Clim. Dynam., 7, 1133–1152, https://doi.org/10.5194/wcd-7-1133-2026, 2026
The Quasi-biennial Oscillation (QBO) dominates variability in the tropical stratosphere, & it impacts surface climate in several parts of the world. However, climate models have been shown to systematically under-estimate the influence of the QBO. Here, we re-evaluate this finding using much larger ensemble sizes than have been previously available based on four separate models. We find that the models are comparatively more successful in capturing QBO influences than reported by previous work.

Atmospheric blocking representation in storm-resolving climate models under historical and future forcing

2026-07-03T19:09:42+02:00

Atmospheric blocking representation in storm-resolving climate models under historical and future forcing
Edgar Dolores-Tesillos, Olivia Martius, and Stephan Pfahl
Weather Clim. Dynam., 7, 1089–1116, https://doi.org/10.5194/wcd-7-1089-2026, 2026
Storm-resolving climate models are gaining attention for their improved simulation of mesoscale processes. Yet, how finer resolution benefits synoptic-scale phenomena remains unclear. We assess atmospheric blocking in the Next Generation Earth Modelling Systems, European Eddy-Rich Earth System Models, and Destination Earth projects, identifying key bias drivers and their response under a high-emissions climate change scenario.

Revisiting barotropic instability from the perspective of wave evolution theory

2026-07-01T19:09:42+02:00

Revisiting barotropic instability from the perspective of wave evolution theory
Yaokun Li
Weather Clim. Dynam., 7, 1073–1088, https://doi.org/10.5194/wcd-7-1073-2026, 2026
This work offers a novel theoretical perspective on classical barotropic instability by integrating modal and nonmodal instabilities within a unified diagnostic framework that emphasizes energy and amplitude variations along propagating wave packets.

Impact, drivers and pathways of two Arctic atmospheric rivers in April 2020

2026-06-25T19:09:42+02:00

Impact, drivers and pathways of two Arctic atmospheric rivers in April 2020
Luisa E. Avilés-Podgurski, Patrick Martineau, Hua Lu, Ayako Yamamoto, Amanda C. Maycock, Andrew Orr, Tony Phillips, Thomas J. Bracegirdle, Anna E. Hogg, Grzegorz Muszynski, and Andrew Fleming
Weather Clim. Dynam., 7, 1051–1071, https://doi.org/10.5194/wcd-7-1051-2026, 2026
Atmospheric rivers (ARs) are narrow filaments of intense poleward water vapour transport. On rare occasions, they reach the Arctic, driving strong warming and melt. In April 2020, two ARs intruded into the central Arctic within one week, raising near-surface temperatures by up to 30°C and leading to extreme precipitation. Their distinct paths and thermodynamic evolution reveal diverse AR impacts on Arctic sea ice and precipitation extremes.

Glacier thinning causes warmer and drier regional climate at the Jostedalsbreen ice cap in western Norway

2026-06-25T19:09:42+02:00

Glacier thinning causes warmer and drier regional climate at the Jostedalsbreen ice cap in western Norway
Kristine Flacké Haualand, Marie Pontoppidan, Henning Åkesson, and Tobias Sauter
Weather Clim. Dynam., 7, 1033–1050, https://doi.org/10.5194/wcd-7-1033-2026, 2026
Melting glaciers worldwide cause changes in land surface type and elevation that may impact regional climate. In a weather and climate model, we find that these changes result in warming and less precipitation, particularly less snow, over Jostedalsbreen ice cap in western Norway. Most of these impacts are related to thinning of the ice cap and the associated lowering of the surface and reduction in orographic lifting of moist air masses. The findings suggest accelerated melting of the ice cap.

Physical processes leading to extreme day-to-day temperature change – Part 2: Future climate change

2026-06-17T19:09:42+02:00

Physical processes leading to extreme day-to-day temperature change – Part 2: Future climate change
Kalpana Hamal and Stephan Pfahl
Weather Clim. Dynam., 7, 1009–1032, https://doi.org/10.5194/wcd-7-1009-2026, 2026
In a warmer climate, extreme day-to-day temperature changes weaken in extratropical regions but intensify in the tropics during December-February. Whereas, during June–August, they show widespread intensification across most regions. Such changes are driven not only by variations in advection but also by adiabatic and diabatic processes. Together, these findings underscore the need for region-specific adaptation strategies to mitigate the risks associated with rapid temperature fluctuations.

A climatological perspective on cyclones and surface impacts in the Eastern Mediterranean using potential vorticity-based classification

2026-06-16T19:09:42+02:00

A climatological perspective on cyclones and surface impacts in the Eastern Mediterranean using potential vorticity-based classification
Tali Sarit Gens, Leehi Magaritz-Ronen, and Shira Raveh-Rubin
Weather Clim. Dynam., 7, 959–977, https://doi.org/10.5194/wcd-7-959-2026, 2026
Cyclones significantly impact daily life in the Eastern Mediterranean. We classify these cyclones using a novel machine learning tool based on their upper-level state of the atmosphere, which identifies six distinct patterns. The patterns directly link to cyclone development and surface impacts, including rainfall and temperature variability and extremes. The findings reveal emerging opposing trends that may indicate future changes in the region's climate towards warmer and drier cyclones.

Global monsoon in ICON: the scale-dependent response of Northern Hemisphere monsoons

2026-06-16T19:09:42+02:00

Global monsoon in ICON: the scale-dependent response of Northern Hemisphere monsoons
Praveen K. Pothapakula, Andreas F. Prein, Anusha Sunkisala, and Anurag Dipankar
Weather Clim. Dynam., 7, 979–1007, https://doi.org/10.5194/wcd-7-979-2026, 2026
Monsoons provide vital rainfall for billions but are hard to forecast. Using a next-generation climate model, we simulated monsoons at different grid spacings. The model captures key seasonal patterns, but finer grids do not always improve accuracy. They can worsen predictions by overproducing intense rain, as they artificially strengthen weather systems like monsoon lows and waves. Our work shows that smarter model physics is needed for reliable future forecasts and climate projections.

A quasi-Lagrangian perspective on the role of dry and moist processes in the formation of blocked North Atlantic–European weather regimes

2026-06-15T19:09:42+02:00

A quasi-Lagrangian perspective on the role of dry and moist processes in the formation of blocked North Atlantic–European weather regimes
Seraphine Hauser, Franziska Teubler, Michael Riemer, and Christian M. Grams
Weather Clim. Dynam., 7, 937–958, https://doi.org/10.5194/wcd-7-937-2026, 2026
The relative roles of dry and moist processes in blocking formation are still not well understood, especially across different blocking types and regions. Using a potential vorticity framework, we study the evolution of large-scale anticyclonic circulation anomalies that are linked to four distinct blocking patterns. We find that the development of anomaly amplitude is shaped mainly by their pathway, which determines the balance between dry and moist contributions, rather than the blocking type.

Predictability of cyclones associated with heavy precipitation events in the Sahara

2026-06-12T19:09:42+02:00

Predictability of cyclones associated with heavy precipitation events in the Sahara
Guorong Ling, Hilla Afargan-Gerstman, and Moshe Armon
Weather Clim. Dynam., 7, 915–935, https://doi.org/10.5194/wcd-7-915-2026, 2026
This research examines how well storms that bring heavy rain to the Sahara can be predicted. Using satellite observations and ensemble weather forecasts, we show that predictability varies by season, location, and circulation pattern, with an upper limit of about ten days. These insights can improve early flood warnings and support better planning for scarce water resources in desert regions.

Quantifying the tropospheric response to individual sudden stratospheric warmings revealed by an ensemble simulation strategy

2026-06-03T19:09:42+02:00

Quantifying the tropospheric response to individual sudden stratospheric warmings revealed by an ensemble simulation strategy
Sheena Loeffel, Philip Rupp, Selina Kiefer, Joaquim G. Pinto, Thomas Birner, and Hella Garny
Weather Clim. Dynam., 7, 895–913, https://doi.org/10.5194/wcd-7-895-2026, 2026
We use a dedicated simulation setup to shed light on the question whether, and why, some sudden stratospheric warming events are more likely than others to develop a surface response. We find that the propensity for downward coupling is unique to each event, and that from day one, the chance of a lower-stratospheric response can be predicted – a key step toward anticipating the surface response, moving beyond 'random' surface outcomes to quantified likelihoods of the ensuing surface response.

Identifying controls of extratropical cyclone intensity at genesis time and during intensification in the North Atlantic and Europe

2026-06-02T19:09:42+02:00

Identifying controls of extratropical cyclone intensity at genesis time and during intensification in the North Atlantic and Europe
Joona Cornér, Clément Bouvier, and Victoria A. Sinclair
Weather Clim. Dynam., 7, 873–893, https://doi.org/10.5194/wcd-7-873-2026, 2026
Understanding the intensification of extratropical cyclones (ETCs) is important from weather forecasting and climate perspectives due to their societal impacts and major role in mid-latitude weather. Here we show that precursors to ETC intensification at genesis time show physically meaningful controls on the final maximum ETC intensity. However, to understand in detail the processes leading to differences in intensity between ETCs, one should study the evolution of multiple ETC precursors.

The role of Rossby wave breaking in the formation and maintenance of tropical-extratropical cloud bands over the South Pacific

2026-05-29T19:09:42+02:00

The role of Rossby wave breaking in the formation and maintenance of tropical-extratropical cloud bands over the South Pacific
Romain Pilon, Andries Jan De Vries, and Daniela I. V. Domeisen
Weather Clim. Dynam., 7, 857–872, https://doi.org/10.5194/wcd-7-857-2026, 2026
South Pacific cloud bands are vital rain sources. Using historical weather data, we investigated how atmospheric waves from the midlatitudes shape these cloud bands. We found that long-lasting cloud bands require sustained high-altitude waves to continuously steer tropical moisture southward. These persistent events occur strictly during the summer. Understanding this dynamic link is essential for improving climate models and predicting how regional rainfall patterns may change in the future.

Dry and moist convective upper bounds for near-surface temperatures

2026-05-27T19:09:42+02:00

Dry and moist convective upper bounds for near-surface temperatures
Quentin Nicolas and Belinda Hotz
Weather Clim. Dynam., 7, 843–856, https://doi.org/10.5194/wcd-7-843-2026, 2026
Heatwaves are intensifying at a fast pace, and how much further they can strengthen is unknown. Our study seeks to estimate a physical upper limit to surface air temperature. We show that, unlike what recent work suggested, the intensity of the most extreme heatwaves may not be constrained by the onset of thunderstorms. Instead, the limit is set by the development of a several-kilometer-deep layer of well-mixed air above the ground, and modulated by a very hot and unstable near-surface layer.

Cold spells induced by slow-moving and amplified large-scale ridge and trough

2026-05-20T19:09:42+02:00

Cold spells induced by slow-moving and amplified large-scale ridge and trough
Morteza Babaei, Rune Grand Graversen, Johannes Patrick Stoll, and Jakub Petříček
Weather Clim. Dynam., 7, 825–841, https://doi.org/10.5194/wcd-7-825-2026, 2026
Extreme weather events have historically caused major challenges for humanity. Yet, our understanding of the mechanisms that contribute to their formation remains unclear. Our study provides evidence that locally amplified and slow-moving Rossby waves are responsible for the formation of extreme cold spells. These findings are obtained based on two novel metrics assessing the amplitude and speed of ridges and troughs separately at all longitudes around latitude circles.