Union-wide
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Inter- and Transdisciplinary Sessions
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AS – Atmospheric Sciences

Programme Group Chair: Philip Stier

MAL11-AS
Vilhelm Bjerknes Medal Lecture by Lucy Carpenter and Arne Richter Award for Outstanding ECS Lecture by Nadia Bloemendaal
Convener: Philip Stier
Orals
| Tue, 16 Apr, 19:00–19:55 (CEST)
 
Room K2
Tue, 19:00
DM1
Division meeting for Atmospheric Sciences (AS)
Convener: Philip Stier
Thu, 18 Apr, 12:45–13:45 (CEST)
 
Room L3
Thu, 12:45

AS1 – Meteorology

AS1.1 EDI

This session welcomes papers on:

1) Forecasting and simulating high impact weather events - research on using advanced artificial intelligence and machine learning techniques to improve numerical weather model prediction of severe weather events (such as winter storms, tropical storms, and severe mesoscale convective storms);

2) Development and improvement of model numerics - basic research on advanced numerical techniques for weather and climate models (such as cloud resolving global model and high-resolution regional models specialized for extreme weather events on sub-synoptic scales);

3) Development and improvement of model physics - progress in research on advanced model physics parametrization schemes (such as stochastic physics, air-wave-oceans coupling physics, turbulent diffusion and interaction with the surface, sub-grid condensation and convection, grid-resolved cloud and precipitation, land-surface parametrization, and radiation);

4) Verification of model physics and forecast products against theories and observations;

5) Data assimilation systems - progress in the development of data assimilation systems for operational applications (such as reanalysis and climate services), research on advanced methods for data assimilation on various scales (such as treatment of model and observation errors in data assimilation, and observational network design and experiments);

6) Ensemble forecasts and predictability - strategies in ensemble construction, model resolution and forecast range-related issues, and applications to data assimilation;

7) Advances and challenges in applying data from various conventional and avant-garde observation platforms to evaluate and improve high-resolution simulations and forecasting.

8) Application of Artificial Intelligence / Machine Learning in weather forecasting in general

Convener: Haraldur Ólafsson | Co-conveners: Jian-Wen Bao, Lisa DegenhardtECSECS
Orals
| Mon, 15 Apr, 08:30–12:30 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Mon, 15 Apr, 16:15–18:00 (CEST) | Display Mon, 15 Apr, 14:00–18:00
 
Hall X5
Orals |
Mon, 08:30
Mon, 16:15
AS1.2 EDI

Forecasting the weather, in particular severe and extreme weather has always been the most important subject in meteorology. This session will focus on recent research and developments on forecasting techniques, in particular those designed for operations and impact oriented. Contributions related to nowcasting, meso-scale and convection permitting modelling, ensemble prediction techniques, and statistical post-processing are very welcome.
Topics may include:
 Nowcasting methods and systems, use of observations and weather analysis
 Mesoscale and convection permitting modelling
 Remote sensing and data assimilation
 Ensemble prediction techniques
 Ensemble-based products for severe/extreme weather forecasting
 Seamless deterministic and probabilistic forecast prediction
 Post-processing techniques, statistical methods in prediction
 Use of machine learning, data mining and other advanced analytical techniques
 Impact oriented weather forecasting
 Presentation of results from relevant international research projects of EU, WMO, and EUMETNET etc.

Key Words: Forecast technique, nowcasting, ensemble prediction, statistics, AI

Co-organized by NH1/NP5
Convener: Yong Wang | Co-conveners: Aitor Atencia, kan dai, Lesley De Cruz, Daniele NeriniECSECS
Orals
| Mon, 15 Apr, 14:00–15:45 (CEST), 16:15–18:00 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Tue, 16 Apr, 10:45–12:30 (CEST) | Display Tue, 16 Apr, 08:30–12:30
 
Hall X5
Orals |
Mon, 14:00
Tue, 10:45
AS1.3 EDI

This session invites contributions spanning all aspects of prediction, predictability and applications on the Subseasonal-to-Seasonal (S2S) (i.e., 2 weeks to 2 months) lead time range. The session welcomes contributions on the following:

(a) The Madden Julian Oscillation (MJO) and other modes of variability impacting the S2S timescale;
(b) Tropical/extratropical wave dynamics;
(c) Teleconnections and cross-timescale interference of climate modes of variability;
(d) Stratosphere-troposphere coupling, land-atmosphere coupling, ocean-atmosphere coupling;
(e) Studies of predictability and predictive skill of atmospheric or surface variables such as sea ice, snow cover, and land surface;
(f) Use of AI/ML methods for S2S prediction, post-processing and attribution;
(g) Case studies of extreme or high-impact event prediction on the S2S timescale; and
(h) User applications, impact studies and climate services on the S2S timescale including, including impact-focused modelling studies and examples of how S2S-derived information can be integrated into decision support systems at the local, regional or international level.

Convener: Christopher White | Co-conveners: Daniela Domeisen, Marisol OsmanECSECS, Joanne Robbins, Frederic Vitart
Orals
| Tue, 16 Apr, 08:30–12:30 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Tue, 16 Apr, 16:15–18:00 (CEST) | Display Tue, 16 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Tue, 16 Apr, 14:00–15:45 (CEST) | Display Tue, 16 Apr, 08:30–18:00
 
vHall X5
Orals |
Tue, 08:30
Tue, 16:15
Tue, 14:00
CL4.3 EDI

This session covers climate predictions from seasonal to multi-decadal timescales and their applications. Continuing to improve such predictions is of major importance to society. The session embraces advances in our understanding of the origins of seasonal to decadal predictability and of the limitations of such predictions, as well as advances in improving the forecast skill and reliability and making the most of this information by developing and evaluating new applications and climate services. The session welcomes contributions from dynamical as well as statistical predictions (including machine learning methods) and their combination. This includes predictions of climate phenomena, including extremes and natural hazards, from global to regional scales, and from seasonal to multi-decadal timescales ("seamless predictions"). The session also covers physical processes relevant to long-term predictability sources (e.g. ocean, cryosphere, or land) and predictions of large-scale atmospheric circulation anomalies associated to teleconnections as well as observational and emergent constraints on climate variability and predictability. Also relevant is the time-dependence of the predictive skill and windows of opportunity. Analysis of predictions in a multi-model framework and innovative ensemble-forecast initialization and generation strategies are another focus of the session. The session pays particular attention to innovative methods of quality assessment and verification of climate predictions, including extreme-weather frequencies, post-processing of climate hindcasts and forecasts, and quantification and interpretation of model uncertainty. We particularly invite contributions presenting the use of seasonal-to-decadal predictions for assessing risks from natural hazards, adaptation and further applications.

Co-organized by AS1/ESSI4/HS13/NH11/NP5/OS1
Convener: Panos J. Athanasiadis | Co-conveners: André Düsterhus, Julia Lockwood, Bianca Mezzina, Lisa DegenhardtECSECS, Leon Hermanson, Leonard Borchert
Orals
| Fri, 19 Apr, 08:30–12:25 (CEST), 14:00–15:35 (CEST)
 
Room 0.31/32
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X5
Orals |
Fri, 08:30
Thu, 16:15
Thu, 14:00
AS1.5 EDI

This session deals with atmospheric convection, being dry, shallow, or deep convection. Contributions on these aspects resulting from the use of large-eddy simulations, convection-permitting simulations, coarser-resolution simulations using parameterised convection and observations are welcome. Studies that investigate the organization of convection, being in idealized set-ups (radiative convective equilibrium and self-aggregation) or in observations, as well as studies that investigate the importance of organization for climate are welcome. Besides this, studies that investigate general aspects of convection such as processes controlling the lifecycle of convection, interactions of convection with other physical processes and representation of convection in numerical weather prediction and climate models, being for instance through the use of machine learning techniques, are also welcome.

Convener: Cathy Hohenegger | Co-conveners: Leo Donner, Holger Tost, Adrian Tompkins
Orals
| Tue, 16 Apr, 14:00–15:45 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Wed, 17 Apr, 16:15–18:00 (CEST) | Display Wed, 17 Apr, 14:00–18:00
 
Hall X5
Orals |
Tue, 14:00
Wed, 16:15
AS1.6 EDI

Understanding severe convection and associated hazardous weather is crucial to mitigate societal impacts now and in a warmer future. However, convective-scale data analysis and severe weather predictions still present significant challenges for atmospheric sciences. Addressing these challenges requires a synergy of high-resolution convection-permitting modelling, observations, and data assimilation advances. For this reason, our session connects recent advancements in convective-scale process modelling, process understanding, data assimilation, prediction, observing systems, and machine learning.

Session objectives:
• To improve the process understanding and modelling of mesoscale and severe convection in current and future climates.
• To improve convective-scale data assimilation, forecasting and observation methodologies.
• To provide a collaborative platform for enhancing the predictability, uncertainty quantification and understanding of severe weather events and their impacts.
• To bridge mesoscale convective studies with novel convective-scale data assimilation and modelling techniques.

Key Topics:
• Dynamics, thermodynamics and microphysics of mesoscale and severe convection on weather and climate timescales.
• Impact of land-convection interactions, considering environmental factors like complex topography, soil moisture feedbacks,or land use (change).
• Advances in convective-scale data assimilation, forecasting and observations.
• Advances in machine learning for improved modelling of convective-scale processes.

Public information:

Solicited authors:
•    Pieter Groenemeijer (European Severe Storms Laboratory) - “Severe Storms Research at ESSL”
•    Laure Raynaud (MeteoFrance) - “ML for weather prediction at Météo-France: current status and future plans”

Convener: Julia CurioECSECS | Co-conveners: Cornelia Klein, Kalli Furtado, Jian Li, Tijana Janjic, Tomislava Vukicevic, Tobias NeckerECSECS
Orals
| Mon, 15 Apr, 08:30–12:30 (CEST)
 
Room M2
Posters on site
| Attendance Mon, 15 Apr, 16:15–18:00 (CEST) | Display Mon, 15 Apr, 14:00–18:00
 
Hall X5
Orals |
Mon, 08:30
Mon, 16:15
AS1.7 EDI

The uncertain response of clouds to global warming is a major contributor to uncertainty in climate sensitivity. Cloud feedback uncertainty is related to a limited understanding of the coupling between clouds, convection and the large-scale circulation across various spatial and temporal scales. Today's wealth of advanced remote-sensing observations and high-resolution modelling data provides comprehensive and complementary information that enables detailed process and lifecycle-based analyses. This session focuses on (1) efforts to advance our understanding of the cloud-circulation coupling and its role in climate change, and (2) Lagrangian studies related to clouds and water vapour. We invite contributions from dedicated field campaigns, from ground-based and satellite remote sensing or in situ measurements, as well as modelling and theoretical studies. This year we particularly welcome early results from the various ongoing model intercomparisons, like EUREC4A-MIP, CP-MIP and Lagrangian LES MIP, but also from the NextGEMS project. We also invite abstracts focusing on the role of mesoscale convective organization, aerosol-cloud interactions, feature tracking and Langrangian cloud modelling.

Convener: Raphaela Vogel | Co-conveners: Matthias Tesche, Claudia Acquistapace, Leif Denby, Geet GeorgeECSECS, Julia KukuliesECSECS, Ann Kristin Naumann
Orals
| Tue, 16 Apr, 16:15–18:00 (CEST)
 
Room 0.11/12, Wed, 17 Apr, 08:30–10:15 (CEST)
 
Room 1.85/86
Posters on site
| Attendance Wed, 17 Apr, 10:45–12:30 (CEST) | Display Wed, 17 Apr, 08:30–12:30
 
Hall X5
Orals |
Tue, 16:15
Wed, 10:45
HS7.1 EDI

Rainfall is a “collective” phenomenon emerging from numerous drops. Understanding the relation between the physics of individual drops and that of a population of drops remains an open challenge, both scientifically and at the level of practical implications. This remains true also for solid precipitation. Hence, it is much needed to better understand small scale spatio-temporal precipitation variability, which is a key driving force of the hydrological response, especially in highly heterogeneous areas (mountains, cities). This hydrological response at the catchment scale is the result of the interplay between the space-time variability of precipitation, the catchment geomorphological / pedological / ecological characteristics and antecedent hydrological conditions. Therefore, (1) accurate measurement and prediction of the spatial and temporal distribution of precipitation over a catchment and (2) the efficient and appropriate description of the catchment properties are important issues in hydrology.

This session will bring together scientists and practitioners who aim to measure and understand precipitation variability from drop scale to catchment scale as well as its hydrological consequences. Contributions addressing one or several of the following topics are especially targeted:
- Novel techniques for measuring liquid and solid precipitation variability at hydrologically relevant space and time scales (from drop to catchment scale), from in situ measurements to remote sensing techniques, and from ground-based devices to spaceborne platforms. Innovative comparison metrics are welcomed;
- Precipitation drop (or particle) size distribution and its small scale variability, including its consequences for precipitation rate retrieval algorithms for radars, commercial microwave links and other remote sensors;
- Novel modelling or characterization tools of precipitation variability from drop scale to catchment scale from various approaches (e.g. scaling, (multi-)fractal, statistic, deterministic, numerical modelling);
- Novel approaches to better identify, understand and simulate the dominant microphysical processes at work in liquid and solid precipitation.
- Applications of measured and/or modelled precipitation fields in catchment hydrological models for the purpose of process understanding or predicting hydrological response.

Co-organized by AS1/NP3
Convener: Auguste Gires | Co-conveners: Katharina Lengfeld, Alexis Berne, Taha Ouarda, Marc Schleiss
Orals
| Wed, 17 Apr, 08:30–10:15 (CEST)
 
Room 2.31
Posters on site
| Attendance Wed, 17 Apr, 16:15–18:00 (CEST) | Display Wed, 17 Apr, 14:00–18:00
 
Hall A
Orals |
Wed, 08:30
Wed, 16:15
AS1.10 EDI

Precipitation, both liquid and solid, is a central element of the global water/energy cycle through its coupling with clouds, water vapor, atmospheric motions, ocean circulation, and land surface processes. Precipitation is also the primary source of freshwater, while it can have tremendous socio-economical impacts associated with extreme weather events such as hurricanes, floods, droughts, and landslides. Accurate and timely knowledge of precipitation characteristics at regional and global scales is essential for understanding how the Earth system operates under changing climatic conditions and for improved societal applications that range from numerical weather prediction to freshwater resource management. This session will host papers on all aspects of precipitation, especially contributions in the following four research areas: Precipitation Measurement: Precipitation measurements (amount, duration, intensity etc) by ground-based in situ sensors (e.g., rain gauges, disdrometers); estimation of accuracy of measurements, comparison of instrumentation. Precipitation Climatology: Regional and global climatology; areal distribution of measured precipitation; classification of precipitation patterns; spatial and temporal characteristics of precipitation; methodologies adopted and their uncertainties; comparative studies. Precipitation Remote Sensing: Remote sensing of precipitation (spaceborne, airborne, ground-based, underwater, or shipborne sensors); methodologies to estimate areal precipitation (interpolation, downscaling, combination of measurements and/or estimates of precipitation); methodologies used for the estimation (e.g., QPE), validation, and assessment of error and uncertainty of precipitation as estimated by remote sensors. A special focus will be on international contributions to the exploitation of the international Global Precipitation Measurement (GPM) mission and preparations for new missions, such as Atmospheric Observing System (AOS), EUMETSAT Polar System-Second Generation (EPS-SG), and Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS), as well as new space-borne instrumentation (AMSR-3).

Convener: Silas Michaelides | Co-conveners: Ehsan SharifiECSECS, Chris Kidd, Giulia Panegrossi, Takuji Kubota
Orals
| Wed, 17 Apr, 08:30–12:25 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Wed, 17 Apr, 16:15–18:00 (CEST) | Display Wed, 17 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Wed, 17 Apr, 14:00–15:45 (CEST) | Display Wed, 17 Apr, 08:30–18:00
 
vHall X5
Orals |
Wed, 08:30
Wed, 16:15
Wed, 14:00
AS1.11 EDI

Cold clouds (mixed-phase and ice) play an important role in the Earth’s radiation budget because of their high temporal and spatial coverage and their interaction with long wave and short wave radiation. Yet, the variability and complexity of their macro- and microphysical properties, a consequence of intricate ice particle nucleation, secondary ice production and growth processes, makes their study extremely challenging. As a result, large uncertainties still exist in our understanding of cold cloud processes, their radiative effects, and their interaction with their environment (in particular, aerosols).

This session aims to advance our comprehension of cold clouds by bringing observation- and modelling-based research together. A diversity of research topics shall be covered, highlighting recent advances in cloud observation techniques, modelling and subsequent process studies:

(1) Airborne, space borne, ground- or laboratory-based measurements and their derived products (e.g. retrievals), which are useful to characterise cloud properties like extent, emissivity, or crystal size distributions, to clarify formation mechanisms, and to provide climatologies.

(2) Process-based, regional and global model simulations that employ observations for better representation of cold cloud microphysical properties and radiative forcing under both current and future climate.

The synthesis of these approaches can uniquely answer questions regarding dynamical influence on cloud formation, life cycle, coverage, microphysical and radiative properties, crystal shapes, sizes and variability of ice particles in mixed-phase as well as ice clouds. Joint observation-modelling contributions are therefore particularly encouraged.

Please also note the session "Atmospheric surface-science and ice nucleating particles" for more experimental studies related to Ice Nucleating Particles (INPs). Abstracts related to ice formation on this more microphysical scale would better fit into this session.

Convener: Christian Rolf | Co-conveners: Luisa Ickes, Odran Sourdeval, Hinrich Grothe, Georgia SotiropoulouECSECS
Orals
| Wed, 17 Apr, 14:00–18:00 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Thu, 18 Apr, 10:45–12:30 (CEST) | Display Thu, 18 Apr, 08:30–12:30
 
Hall X5
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X5
Orals |
Wed, 14:00
Thu, 10:45
Thu, 14:00
CR6.2 EDI | PICO

Snow cover characteristics (e.g., spatial distribution, surface and internal physical properties) are continuously evolving over a wide range of scales due to meteorological conditions, such as precipitation, wind, and radiation.
Most processes occurring in the snow cover depend on the vertical and horizontal distribution of its physical properties, which are primarily controlled by the microstructure of snow (e.g., density and specific surface area). In turn, snow metamorphism changes the microstructure, leading to feedback loops that affect the snow cover on coarser scales. This can have far-reaching implications for a wide range of applications, including snow hydrology, weather forecasting, climate modelling, avalanche hazard forecasting, and the remote sensing of snow. The characterization of snow thus demands synergetic investigations of the hierarchy of processes across the scales, ranging from explicit microstructure-based studies to sub-grid parameterizations for unresolved processes in large-scale phenomena (e.g., albedo and drifting snow).

This session is therefore devoted to modelling and measuring snow processes across scales. The aim is to gather researchers from various disciplines to share their expertise on snow processes in seasonal and perennial snowpacks. We invite contributions ranging from “small” scales, as encountered in microstructure studies, over “intermediate” scales typically relevant for 1D snowpack models, up to “coarse” scales, that typically emerge for spatially distributed modelling over mountainous or polar snow- and ice-covered regions. Specifically, we welcome contributions reporting results from field, laboratory, and numerical studies of the physical and chemical evolution of snowpacks. We also welcome contributions reporting statistical or dynamic downscaling methods of atmospheric driving data, representation of sub-grid processes in coarse-scale models, and evaluation of model performance and associated uncertainties.

Co-organized by AS1/HS13
Convener: Nora Helbig | Co-conveners: Neige Calonne, Richard L.H. Essery, Benjamin Walter, Christopher MarshECSECS
PICO
| Tue, 16 Apr, 08:30–10:15 (CEST)
 
PICO spot 4
Tue, 08:30
AS1.13 EDI

Clouds play an important role in the Polar climate due to their interaction with radiation and their role in the hydrological cycle linking poleward water vapour transport with precipitation. Cloud and precipitation properties depend on the atmospheric dynamics and moisture sources and transport, as well as on aerosol particles, which can act as cloud condensation and ice nuclei. These processes are complex and are not well represented in the models. While measurements of cloud and precipitation microphysical properties in the Arctic and Antarctic regions are challenging, they are highly needed to evaluate and improve cloud processes representation in the models used for polar and global climate and cryosphere projections.

This session aims at bringing together researchers using observational and/or modeling approaches (at various scales) to improve our understanding of polar tropospheric clouds, precipitation, and related mechanisms and impacts. Contributions are invited on various relevant processes including (but not limited to):
- Drivers of cloud/precipitation microphysics at high latitudes,
- Sources of cloud nuclei both at local and long range,
- Linkages of polar clouds/precipitation to the moisture sources and transport, including including extreme transport events (e.g., atmospheric rivers, moisture intrusions),
- Relationship of moisture/cloud/precipitation processes to the atmospheric dynamics, ranging from synoptic and meso-scale processes to teleconnections and climate indices,
- Interactions between clouds and radiation, including impacts on the surface energy balance,
- Impacts that the clouds/precipitation in the Polar Regions have on the polar and global climate system, surface mass and energy balance, sea ice and ecosystems.

Papers including new methodologies specific to polar regions are encouraged, such as (i) improving polar cloud/precipitation parameterizations in atmospheric models, moisture transport events detection and attribution methods specifically in the high latitudes, and (ii) advancing observations of polar clouds and precipitation. We would like to emphasize collaborative observational and modeling activities, such as the Year of Polar Prediction (YOPP), Polar-CORDEX, the (AC)3 project on Arctic Amplification, MOSAiC and other measurement campaigns in the Arctic and Southern Ocean/Antarctica and encourage related contributions.

Co-organized by CL2/CR7
Convener: Irina V. Gorodetskaya | Co-conveners: Tom Lachlan-Cope, Susanne Crewell, Florian Sauerland, Maximilian Maahn
Orals
| Thu, 18 Apr, 08:30–10:15 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Fri, 19 Apr, 10:45–12:30 (CEST) | Display Fri, 19 Apr, 08:30–12:30
 
Hall X5
Posters virtual
| Fri, 19 Apr, 14:00–15:45 (CEST) | Display Fri, 19 Apr, 08:30–18:00
 
vHall X5
Orals |
Thu, 08:30
Fri, 10:45
Fri, 14:00
NH1.5 EDI

Lightning is the energetic manifestation of electrical breakdown in the atmosphere, occurring as a result of charge separation processes operating on micro and macro-scales, leading to strong electric fields within thunderstorms. Lightning is associated with tropical storms and severe weather, torrential rains and flash floods. It has significant effects on various atmospheric layers and drives the fair-weather electric field. It is a strong indicator of convective processes on regional and global scales, potentially associated with climate change. Lightning produces nitrogen oxides, which are a precursor to ozone production. Thunderstorms and lightning are essential parts of the Global Electrical Circuit (GEC) and control the fair weather electric field. They are also associated with the production of energetic radiation up to tens of MeV on time scales from sub-millisecond (Terrestrial Gamma-ray Flashes) to tens of seconds (gamma-ray glows).

This session seeks contributions from research in atmospheric electricity with emphasis on:

Atmospheric electricity in fair weather and the global electrical circuit
Effects of dust and volcanic ash on atmospheric electricity
Thunderstorm dynamics and microphysics
Middle atmospheric Transient Luminous Events
Energetic radiation from thunderstorms and lightning
Experimental investigations of lightning discharge physics processes
Remote sensing of lightning and related phenomena by space-based sensors
Thunderstorms, flash floods, tropical storms and severe weather
Connections between lightning, climate and atmospheric chemistry
Modeling of thunderstorms and lightning
Now-casting and forecasting of thunderstorms using machine learning and AI
Regional and global lightning detection networks
Lightning Safety and its societal effects

Co-organized by AS1, co-sponsored by AGU-ASE
Convener: Yoav Yair | Co-conveners: Sonja Behnke, Karen Aplin, David SarriaECSECS, Xiushu Qie
Orals
| Thu, 18 Apr, 08:30–12:25 (CEST), 14:00–17:55 (CEST)
 
Room 1.31/32
Posters on site
| Attendance Fri, 19 Apr, 10:45–12:30 (CEST) | Display Fri, 19 Apr, 08:30–12:30
 
Hall X4
Posters virtual
| Fri, 19 Apr, 14:00–15:45 (CEST) | Display Fri, 19 Apr, 08:30–18:00
 
vHall X4
Orals |
Thu, 08:30
Fri, 10:45
Fri, 14:00
AS1.15

The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) satellite mission aims to improve our understanding of cloud-aerosol-radiation interactions and Earth radiation budget, such they can be modelled with better reliability in climate and numerical weather prediction models. To achieve this objective, EarthCARE will measure the three-dimensional structure of clouds, precipitation and aerosols, together with collocated observations of solar and terrestrial radiation. EarthCARE will provide unique co-registered observations from a suite of four instruments located on a common platform: (1) ATmospheric LIDar (ATLID), Cloud Profiling Radar (CPR), Multi- Spectral Imager (MSI) and BroadBand Radiometer (BBR). EarthCARE global observations include vertical profiles of natural and anthropogenic aerosols, the vertical contribution of ice and liquid water content, the cloud mesoscale distribution, precipitation microphysics, estimates of particle size, convective vertical air motions, as well as of atmospheric radiative heating and cooling profiles.The launch of this joint European-Japanese mission is planned by mid-2024, providing unique data continuing the heritage measurements by CloudSat, CALIPSO and Aeolus, and bridging towards future missions such as NASA's Atmosphere Observing System mission (AOS) or Aeolus-2.

Convener: Thorsten Fehr | Co-conveners: Takuji Kubota, Robin Hogan, Hajime Okamoto
Orals
| Thu, 18 Apr, 10:45–12:30 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X5
Orals |
Thu, 10:45
Thu, 16:15
Thu, 14:00
AS1.16 EDI

Cloud feedbacks are the dominant uncertainty in assessing global and regional climate sensitivity. As such, improved understanding of the key processes involved in cloud formation, development and radiative effects will support better representations of these processes in climate models and a reduction in the uncertainty in future climate predictions.

Just as cloud formation could be said to begin at the on the surface of aerosol particles, we will begin this session exploring aerosol physics, aerosol generation, emission and properties, and the associated heterogeneous ice nucleation. There will be a particular focus on ice-nucleating particles, which play a fundamental role in clouds with high feedback uncertainty. Atmospheric aerosol-cloud-climate interactions (e.g. heterogeneous nucleation, particle oxidation, photosensitization and the consequent emission of volatile organic compounds (VOCs),...) are also fundamental processes in the atmosphere that regulate energy transfer, cloud dynamics and precipitation formation.

From this aerosol perspective of cloud formation and development, we then look to explore the atmospheric and cloud processes that can influence cloud radiative effect, such as secondary ice production, ocean or land surface variability, meteorology or large-scale atmospheric circulation. Finally, we welcome studies providing theory and quantification of cloud radiative effect and cloud feedback.

This session invites contributions towards reducing the uncertainty in climate sensitivity due to clouds and aerosol-cloud interactions using both observational (in-situ, remote sensing, laboratory) and modelling approaches (process-based or statistical and across the full range of spatial and temporal scales), as well as work leading to a better fundamental understanding of cloud processes, aerosol emissions and ice nucleation processes.

Topics covered in this session are:

- Atmospheric surface-science and the experimental and theoretical approaches investigating the emission and uptake of aerosols in the atmosphere and the relevant atmospheric interactions (e.g. ice nucleation processes and photochemistry at water/air interface) to fill the gap between the large-scale atmospheric processes and gas-, water-, and ice-aerosol interactions.
- Laboratory studies related to aerosol, cloud condensation nuclei, ice nucleating particles or secondary ice processes
- Ice nucleation processes and characterizing INP in the atmosphere
- Modelling and observations of Aerosol-cloud interactions
- Cloud processes and microphysics
- Improving parameterisations associated with cloud formation in models – deep convective clouds, mixed phase clouds, meso-scale convective systems
- Regional cloud drivers, including high latitudes and tropics
- Arctic Amplification and the effect of polar clouds on global climate system
- Cloud feedback and controlling factor analyses
- Effects of circulation on cloud radiative effects and feedbacks


Solicited Speaker: Ottmar Möhler, Institute of Meteorology and Climate Research, Atmospheric Aerosol Research Division (IMK-AAF), Karlsruhe Institute of Technology (KIT), Germany.
Solicited Presentation: "Sources and abundance of ice nucleating particles derived from long-term measurements at high time resolution".

Convener: Floortje van den HeuvelECSECS | Co-conveners: Hinrich Grothe, Declan FinneyECSECS, Ahmed Abdelmonem, Joanna DysonECSECS, Kwinten Van Weverberg
Orals
| Thu, 18 Apr, 16:15–18:00 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Fri, 19 Apr, 10:45–12:30 (CEST) | Display Fri, 19 Apr, 08:30–12:30
 
Hall X5
Orals |
Thu, 16:15
Fri, 10:45
AS1.17 EDI

The understanding of tropical phenomena and their representation in numerical models still raise important scientific and technical questions, particularly in the coupling between the dynamics and diabatic processes. Among these phenomena, tropical cyclones (TC) are of critical interest because of their societal impacts and because of uncertainties in how their characteristics (cyclogenesis processes, occurrence, intensity, latitudinal extension, translation speed) will change in the framework of global climate change. The monitoring of TCs, their forecasts at short to medium ranges, and the prediction of TC activity at extended range (15-30 days) and seasonal range are also of great societal interest.
The aim of the session is to promote discussions between scientists focusing on the physics and dynamics of tropical phenomena. This session is thus open to contributions on all aspects of tropical meteorology between the convective and planetary scale, such as:

- Tropical cyclones,
- Convective organisation,
- Diurnal variations,
- Local circulations (i.e. island, see-breeze, etc.),
- Monsoon depressions,
- Equatorial waves and other synoptic waves (African easterly waves, etc.),
- The Madden-Julian oscillation,
- etc.

We especially encourage contributions of observational analyses and modelling studies of tropical cyclones and other synoptic-scale tropical disturbances including the physics and dynamics of their formation, structure, and intensity, and mechanisms of variability of these disturbances on intraseasonal to interannual and climate time scales.

Findings from recent field campaigns are also encouraged.

Convener: Enrico Scoccimarro | Co-conveners: Allison Wing, Alyssa Stansfield, Leone Cavicchia, Eric Maloney
Orals
| Mon, 15 Apr, 08:30–12:30 (CEST)
 
Room 0.14
Posters on site
| Attendance Mon, 15 Apr, 16:15–18:00 (CEST) | Display Mon, 15 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Mon, 15 Apr, 14:00–15:45 (CEST) | Display Mon, 15 Apr, 08:30–18:00
 
vHall X5
Orals |
Mon, 08:30
Mon, 16:15
Mon, 14:00
AS1.18 EDI

Regional monsoons and the global monsoon circulation to which they belong have profound impacts on water, energy, and food security. Monsoons cause severe floods and droughts as well as undergoing variability on subseasonal, interannual and decadal-to-multi-decadal time scales. In addition to their profound local effects, monsoon variability also causes global-scale impacts via teleconnections.

Monsoons are complex phenomena involving coupled atmosphere-ocean-land interactions and remain notoriously difficult to forecast at leads times ranging from numerical weather prediction (NWP) to long-term climate projections. A better understanding of monsoon physics and dynamics, with more accurate simulation, prediction and projection of monsoon systems is therefore of great importance.

This session invites presentations on any aspects of monsoon research in present-day, future and palaeoclimate periods, involving observations, modelling, attribution, prediction and climate projection. Topics ranging from theoretical works based on idealized planets and ITCZ frameworks to the latest field campaign results are equally welcomed, as is work on impacts, extremes, NWP modelling, S2S and decadal forecasting, and the latest CMIP6 findings. Applications of AI/ML to monsoon studies are also encouraged.

Co-organized by CL4
Convener: Andrew Turner | Co-conveners: Roberta D'AgostinoECSECS, Kyung-Ja Ha, Jianping Li
Orals
| Mon, 15 Apr, 14:00–15:45 (CEST), 16:15–18:00 (CEST)
 
Room 0.14
Posters on site
| Attendance Tue, 16 Apr, 10:45–12:30 (CEST) | Display Tue, 16 Apr, 08:30–12:30
 
Hall X5
Posters virtual
| Tue, 16 Apr, 14:00–15:45 (CEST) | Display Tue, 16 Apr, 08:30–18:00
 
vHall X5
Orals |
Mon, 14:00
Tue, 10:45
Tue, 14:00
AS1.19 EDI

The atmospheric water cycle is a key component of the climate system, and links across many scientific disciplines. Processes interact with dynamics at different scales throughout the atmospheric life cycle of water vapour from evaporation to precipitation. This session sets the focus on understanding the interaction between processes, their dynamics and characteristics of the water cycle, covering the entire atmospheric life cycle from evaporation, atmospheric moisture transport, to cloud microphysics and precipitation processes as observed from in-situ and remote sensing instrumentation, recorded by paleo-/climate archives, and as simulated by models for past, present and future climates.

We invite studies

* focusing on the understanding and impacts of features of the atmospheric water cycle related to weather systems, with a special focus on the role of Atmospheric Rivers;

* investigating the large-scale drivers behind the past, ongoing and future variability and trends within the atmospheric water cycle, from field campaigns (YOPP, MOSAiC, (AC)3, ISLAS, EUREC4A etc.), long-term observations, reanalysis data, regional to global model simulations, or (isotopic) data assimilation;

* reconstructing past hydroclimates based on paleo-proxy records from archives such as ice cores, lake sediments, tree-rings or speleothems;

* applying methods such as tagged water tracers and Lagrangian moisture source diagnostics to identify source-sink relationships and to evaluate model simulations of the water cycle;

* using the isotopic fingerprint of atmospheric processes and weather systems to obtain new mechanistic insights into changes in the water cycle;

* describing the global and regional state of the atmospheric water cycle (e.g. monsoon systems) with characteristics such as the recycling ratio, life time of water vapour, and moisture transport properties.

We particularly encourage contributions linking across neighbouring disciplines, such as atmospheric science, climate, paleoclimate, glaciology, and hydrology.

Co-organized by CL4
Convener: Iris ThurnherrECSECS | Co-conveners: Seung Hun Baek, Camilla F. BrunelloECSECS, Bo DongECSECS, Marina Duetsch, Alexandre M. Ramos, Harald Sodemann
Orals
| Thu, 18 Apr, 14:00–15:45 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Fri, 19 Apr, 16:15–18:00 (CEST) | Display Fri, 19 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Fri, 19 Apr, 14:00–15:45 (CEST) | Display Fri, 19 Apr, 08:30–18:00
 
vHall X5
Orals |
Thu, 14:00
Fri, 16:15
Fri, 14:00
HS7.9 EDI | PICO

Traditionally, hydrologists focus on the partitioning of precipitation water on the surface, into evaporation and runoff, with these fluxes being the input to their hydrological models. However, more than half of the evaporation globally comes back as precipitation on land, ignoring an important feedback of the water cycle if the previous focus applied. Land-use and water-use changes, as well as climate variability and change alter, not only, the partitioning of water but also the atmospheric input of water as precipitation, related with this feedback, at both remote and local scales.

This session aims to:
i. investigate the remote and local atmospheric feedbacks from human interventions such as greenhouse gasses, irrigation, deforestation, and reservoirs on the water cycle, precipitation and climate, based on observations and coupled modelling approaches,
ii. investigate the use of hydroclimatic frameworks such as the Budyko framework to understand the human and climate effects on both atmospheric water input and partitioning,
iii. explore the implications of atmospheric feedbacks on the hydrological cycle for land and water management.

Typically, studies in this session are applied studies using fundamental characteristics of the atmospheric branch of the hydrological cycle on different scales. These fundamentals include, but are not limited to, atmospheric circulation, humidity, hydroclimate frameworks, residence times, recycling ratios, sources and sinks of atmospheric moisture, energy balance and climatic extremes. Studies may also evaluate different sources of data for atmospheric hydrology and implications for inter-comparison and meta-analysis. For example, observations networks, isotopic studies, conceptual models, Budyko-based hydro climatological assessments, back-trajectories, reanalysis and fully coupled Earth system model simulations.

Co-organized by AS1/CL2
Convener: Lan Wang-ErlandssonECSECS | Co-conveners: Ruud van der EntECSECS, Gonzalo Miguez Macho, Fernando Jaramillo, Christoforos Pappas
PICO
| Wed, 17 Apr, 16:15–18:00 (CEST)
 
PICO spot 3
Wed, 16:15
AS1.22

This session investigates mid-latitude cyclones and storms on both hemispheres. We invite studies considering cyclones in all different stages of their life cycles, from initial generation to the final development, including studies to large- and synoptic-scale conditions influencing cyclones’ growth to a severe storm, their dissipation, and related socioeconomic impacts.
Papers are welcome, which focus also on the diagnostic of observed past and recent trends, as well as on future storm development under changed climate conditions. This will include storm predictability studies on different scales. Finally, the session will also invite studies investigating impacts related to storms: Papers are welcome dealing with vulnerability, diagnostics of sensitive social and infrastructural categories and affected areas of risk for property damages. Which risk transfer mechanisms are currently used, depending on insured and economic losses? Which mechanisms (e.g., new reinsurance products) are already implemented or will be developed in order to adapt to future loss expectations?

Co-organized by CL5/NH1
Convener: Gregor C. Leckebusch | Co-conveners: Jennifer Catto, Joaquim G. Pinto, Uwe Ulbrich
Orals
| Fri, 19 Apr, 08:30–10:15 (CEST)
 
Room 0.11/12
Posters on site
| Attendance Fri, 19 Apr, 10:45–12:30 (CEST) | Display Fri, 19 Apr, 08:30–12:30
 
Hall X5
Posters virtual
| Fri, 19 Apr, 14:00–15:45 (CEST) | Display Fri, 19 Apr, 08:30–18:00
 
vHall X5
Orals |
Fri, 08:30
Fri, 10:45
Fri, 14:00
HS2.1.5 EDI

Water is a strategic issue in drylands, where ecosystems and their inhabitants strongly rely on the scarce and often intermittent water availability or its low quality. The characteristics of drylands increase their vulnerability to climate change and susceptibility to the impact of short- to long-term extreme events and processes, such as floods, droughts, and desertification. These events can reshape the landscape through the mobilisation of surface sediments, deposits of which preserve archives of past Earth system states, including changes in the extent of deserts. Over the last century, anthropogenic modifications of all kinds and intensities have affected surface conditions. In drylands and Mediterranean hydrosystems, agricultural water use is constantly increasing threatening the sustainability of the surface and groundwater reservoirs, and their hydrology is then continuously evolving. Nevertheless, the study of hydroclimatic processes in drylands remains at the periphery of many geoscientific fields. A proper understanding of the hydrological, hydrometeorological and (paleo)climatic processes in these regions is a cornerstone to achieving the proposed sustainable development goals we set for the end of this century.

This session welcomes contributions from scientific disciplines addressing any of the drylands' full range of environmental and water-related processes. The purpose is to foster interdisciplinary research and expand knowledge and methods established in individual subdisciplines. We will address hydrological issues across global drylands, and devote a section of our session to a geographical focus on the Mediterranean region to analyse the changes in hydrologic processes and fluxes unique to that region.

Co-organized by AS1/CL2/GM7/NH1
Convener: Moshe ArmonECSECS | Co-conveners: Lionel Jarlan, Andries Jan De VriesECSECS, María José PoloECSECS, Pedro AlencarECSECS, Said Khabba, Rodolfo NóbregaECSECS
Orals
| Wed, 17 Apr, 10:45–12:30 (CEST), 14:00–15:35 (CEST)
 
Room 3.16/17, Thu, 18 Apr, 08:30–10:05 (CEST)
 
Room 3.16/17
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
 
Hall A
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall A
Orals |
Wed, 10:45
Thu, 16:15
Thu, 14:00
HS7.5 EDI

Extreme hydro-meteorological events drive many hydrologic and geomorphic hazards, such as floods, landslides and debris flows, which pose a significant threat to modern societies on a global scale. The continuous increase of population and urban settlements in hazard-prone areas in combination with evidence of changes in extreme weather events lead to a continuous increase in the risk associated with weather-induced hazards. To improve resilience and to design more effective mitigation strategies, we need to better understand the triggers of these hazards and the related aspects of vulnerability, risk, mitigation and societal response.
This session aims at gathering contributions dealing with various hydro-meteorological hazards that address the aspects of vulnerability analysis, risk estimation, impact assessment, mitigation policies and communication strategies. Specifically, we aim to collect contributions from academia, industry (e.g. insurance) and government agencies (e.g. civil protection) that will help identify the latest developments and ways forward for increasing the resilience of communities at local, regional and national scales, and proposals for improving the interaction between different entities and sciences.
Contributions focusing on, but not limited to, novel developments and findings on the following topics are particularly encouraged:
- Physical and social vulnerability analysis and impact assessment of hydro-meteorological hazards
- Advances in the estimation of socioeconomic risk from hydro-meteorological hazards
- Characteristics of weather and precipitation patterns leading to high-impact events
- Relationship between weather and precipitation patterns and socio-economic impacts
- Socio-hydrological studies of the interplay between hydro-meteorological hazards and societies
- Hazard mitigation procedures
- Strategies for increasing public awareness, preparedness, and self-protective response
- Impact-based forecast, warning systems, and rapid damage assessment.
- Insurance and reinsurance applications

Co-organized by AS1/GM4/NH1/NP8
Convener: Francesco Marra | Co-conveners: Elena CristianoECSECS, Nadav Peleg, Efthymios Nikolopoulos, Giuliano Di Baldassarre
Orals
| Wed, 17 Apr, 10:45–12:30 (CEST), 14:00–15:45 (CEST)
 
Room B, Thu, 18 Apr, 16:15–18:00 (CEST)
 
Room B
Posters on site
| Attendance Thu, 18 Apr, 10:45–12:30 (CEST) | Display Thu, 18 Apr, 08:30–12:30
 
Hall A
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall A
Orals |
Wed, 10:45
Thu, 10:45
Thu, 14:00
NH1.2

With global climate change affecting the frequency and severity of extreme meteorological and hydrological events, it is particularly necessary to develop models and methodologies for a better understanding and forecasting of present-day weather induced hazards. Future changes in the event characteristics as well as changes in vulnerability and exposure are among the further factors for determining risks for infrastructure and society, and for the development of suitable adaptation measures. This session considers extreme events that lead to disastrous hazards induced by severe weather and climate change. These can, e.g., be tropical or extratropical rain- and wind-storms, hail, tornadoes or lightning events, but also (toxic) floods, long-lasting periods of drought, periods of extremely high or of extremely low temperatures, etc. Papers are sought which contribute to the understanding of their occurrence (conditions and meteorological development), to the augmentation of risks and impacts due to specific sequences of extremes, for example droughts, heavy rainfall and floods, to assessment of their risk (economic losses, infrastructural damages, human fatalities, pollution), and their future changes, to studies of recent extreme events occurring in 2023, to the ability of models to reproduce them and methods to forecast them or produce early warnings, to proactive planning focusing on damage prevention and damage reduction. In order to understand fundamental processes, papers are also encouraged that look at complex extreme events produced by combinations or sequences of factors that are not extreme by themselves. The session serves as a forum for the interdisciplinary exchange of research approaches and results, involving meteorology, hydrology, environmental effects, hazard management and applications like insurance issues.

Including Sergey Soloviev Medal Lecture
Co-organized by AS1/HS13
Convener: Athanasios Loukas | Co-conveners: Maria-Carmen Llasat, Uwe Ulbrich, Hadas Saaroni, Silvia Kohnová
Orals
| Wed, 17 Apr, 08:30–12:30 (CEST), 14:00–15:45 (CEST)
 
Room C
Posters on site
| Attendance Thu, 18 Apr, 10:45–12:30 (CEST) | Display Thu, 18 Apr, 08:30–12:30
 
Hall X4
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X4
Orals |
Wed, 08:30
Thu, 10:45
Thu, 14:00
AS1.26 EDI

The frequencies and intensities of extreme events such as floods, tropical cyclones, heat waves, droughts etc. are increased in many regions across the globe and now of serious concern due to their socio-economic Impact. Hence understanding of the mechanism, pattern and characteristics of such events have been the focus of many recent studies. This session invites abstracts on observational and numerical modeling studies aimed to enhance the understanding of the spatial and temporal characteristics and predictability of the extreme events. This session also welcomes the submissions on model simulations and evaluations aimed to advance the understanding of the physics and dynamics associated with the extreme events. In particular, abstracts are encouraged on regional-scale analysis of the historical extreme events and their projections which would assist the policy makers to build more resilient societies to face the extreme event related disasters.

Co-sponsored by AGU and AOGS
Convener: Sridhara Nayak | Co-conveners: NETRANANDA SAHU, Shiori Sugimoto, Yeonjoo Kim, Suman MaityECSECS
Orals
| Fri, 19 Apr, 08:30–12:30 (CEST)
 
Room M1
Posters on site
| Attendance Fri, 19 Apr, 16:15–18:00 (CEST) | Display Fri, 19 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Fri, 19 Apr, 14:00–15:45 (CEST) | Display Fri, 19 Apr, 08:30–18:00
 
vHall X5
Orals |
Fri, 08:30
Fri, 16:15
Fri, 14:00
CL2.3 EDI

Recent extreme events and climate conditions unprecedented in the observational record have had high-impact consequences globally. Some of these events would have arguably been nearly impossible without human-made climate change and broke records by large margins. Furthermore, compound behaviour and cascading effects and risks are becoming evident. Finally, continuing warming does not only increase the frequency and intensity of events like these, or other until yet unprecedented extremes, it also potentially increases the risk of crossing tipping points and triggering abrupt changes. In order to increase preparedness for high impact climate events, it is important to develop methods and models that are able to represent these events and their impacts, and to better understand how to reduce the risks.

To provide more actionable information for risk assessments, climate storylines have become a popular approach to complement probabilistic event attribution and climate projection. According to the latest IPCC-WG1 report, “the term storyline is used both in connection to scenarios or to describe plausible trajectories of weather and climate conditions or events”. Various types of storylines exist, such as event-based storylines, dynamical storylines of physically plausible climate change, or pseudo-global-warming experiments. This session aims to bring together the latest research on modelling, understanding, development of storylines and managing plausible past and future climate outcomes, extreme and low-probability events, and their impacts. Studies can range across spatial and temporal scales, and can cover compound, cascading, and connected extremes, worst-case scenarios, event-based and dynamical storylines, as well as the effect of tipping points and abrupt changes driven by climate change, societal response, adaptation limits, or other mechanisms (e.g., volcanic eruption).

We welcome a variety of methods aiming to quantify and understand high-impact climate events in present and future climates and, ultimately, provide actionable climate information. We invite work including but not limited to the variety of storyline approaches, model experiments and intercomparisons, insights from paleo archives, climate projections (including large ensembles, and unseen events), and attribution studies.

The session is further informed by the World Climate Research Programme lighthouse activities on Safe Landing Pathways and Understanding High-Risk Events.

Public information:

This session brings together the latest research on exceptional weather and high-impact climate events. It is a follow up from previous year’s successful sessions CL3.2.8 on low-likelihood high-impact events and CL4.8 on storyline approaches. The session is further informed by the World Climate Research Programme lighthouse activities on Safe Landing Pathways and Understanding High-Risk Events. Our aim is to make preparedness to exceptional weather extremes standard practice in the transition to a climate resilient society: https://unseennetwork.org/.

Co-organized by AS1/HS13/NH11
Convener: Timo KelderECSECS | Co-conveners: Marylou AthanaseECSECS, Erich Fischer, Patrick Ludwig, Henrique Moreno Dumont GoulartECSECS, Laura Suarez-GutierrezECSECS, Karin van der Wiel
Orals
| Wed, 17 Apr, 14:00–18:00 (CEST)
 
Room E2
Posters on site
| Attendance Tue, 16 Apr, 16:15–18:00 (CEST) | Display Tue, 16 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Tue, 16 Apr, 14:00–15:45 (CEST) | Display Tue, 16 Apr, 08:30–18:00
 
vHall X5
Orals |
Wed, 14:00
Tue, 16:15
Tue, 14:00
AS1.29 EDI

Dynamics, transport processes and chemical composition in the stratosphere and and the related feedbacks are inextricably linked. Changes in any of these aspects are in turn linked to changes in tropospheric circulation, climate, and weather events via two-way coupling. Such changes can be driven or triggered by a variety of natural (e.g., ENSO, QBO, SSWs, solar and volcanic activity, wildfires) and anthropogenic (emissions of radiatively or chemically active gases) processes. Better understanding of these processes and their consequences is important to improving understanding and prediction of changes in weather, climate, and air quality, including those related to extreme weather events. We welcome abstracts based on observational and modelling studies that explore dynamical, chemical, and transport processes in the stratosphere and their links to surface conditions on all time scales. Combined use of modelling and data analysis is particularly encouraged, including climate model and reanalysis comparisons with existing satellite and ground-based datasets, plans for new missions or model / data assimilation development, and studies highlighting new analytical approaches, e.g., based on machine learning, for evaluating and linking stratospheric processes with surface weather and climate.

Convener: Mohamadou DialloECSECS | Co-conveners: Thomas Reichler, Gloria Manney, Farahnaz Khosrawi, Masatomo Fujiwara, Bo Christiansen, Gabriel ChiodoECSECS
Orals
| Tue, 16 Apr, 08:30–12:25 (CEST)
 
Room M1
Posters on site
| Attendance Mon, 15 Apr, 10:45–12:30 (CEST) | Display Mon, 15 Apr, 08:30–12:30
 
Hall X5
Orals |
Tue, 08:30
Mon, 10:45
AS1.30

The composition of the upper troposphere and the lower stratosphere (UTLS) plays a key role in the climate system. Our understanding of the interactions between dynamics, chemistry, and climate in (and around) this region is rapidly advancing thanks to both observational and modelling studies. In this session, we invite presentations on dynamical, transport and chemical processes determining the variability and long-term trends in the composition of the UTLS, and related effects on radiation and dynamics. We particularly encourage contributions introducing recent observations (both in situ and remote sensing-based) as well as models of various complexity ranging from comprehensive chemistry climate models to idealized and conceptual models.
This year, special focus topics will include recent field and modelling experiments investigating the impact of extreme events, summer monsoons and convective transport on the UTLS (e.g., volcanic eruptions, wildfires, and the ACCLIP, DCOTTS, and PHILEAS projects).

Convener: Johannes Laube | Co-conveners: Aurélien Podglajen, Xinyue Wang, Markus JessweinECSECS, Daniel Kunkel
Orals
| Mon, 15 Apr, 14:00–15:45 (CEST), 16:15–18:00 (CEST)
 
Room M2
Posters on site
| Attendance Tue, 16 Apr, 10:45–12:30 (CEST) | Display Tue, 16 Apr, 08:30–12:30
 
Hall X5
Orals |
Mon, 14:00
Tue, 10:45
AS1.31 EDI

Internal gravity waves (IGWs) still pose major questions in the study of both atmospheric and ocean sciences, and stellar physics. Important issues include IGW radiation from their various relevant sources, IGW reflection at boundaries, their propagation through and interaction with a larger-scale flow, wave-induced mean flow, wave-wave interactions in general, wave breaking and its implications for mixing, and the parameterization of these processes in models not explicitly resolving IGWs. The observational record, both on a global scale and with respect to local small-scale processes, is not yet sufficiently able to yield appropriate constraints. The session is intended to bring together experts from all fields of geophysical and astrophysical fluid dynamics working on related problems. Presentations on theoretical, modelling, experimental, and observational work with regard to all aspects of IGWs are most welcome, including those on major collaborative projects, which seek to accurately parameterize the role of IGWs in numerical models.

Co-organized by NP7/OS4
Convener: Claudia Stephan | Co-conveners: Katherine GraysonECSECS, Chantal Staquet, Ulrich Achatz
Orals
| Tue, 16 Apr, 08:30–10:10 (CEST)
 
Room M2
Posters on site
| Attendance Tue, 16 Apr, 16:15–18:00 (CEST) | Display Tue, 16 Apr, 14:00–18:00
 
Hall X5
Orals |
Tue, 08:30
Tue, 16:15
AS1.32 EDI

Recent extreme weather and climate episodes, like the recurrent and concurrent summer heatwaves, summer flooding (e.g. in Germany in 2021 or in Spain in September 2023), or winter cold waves (e.g. in the US in February 2021), highlight the need to further our understanding of the jets and the associated linear and non-linear (quasi-stationary) planetary and synoptic-scale Rossby wave dynamics in the atmosphere, and their impacts on weather and climate events.

Abstracts are solicited that are dedicated to:
(1) The dynamics of linear wave propagation or quasi-stationarity, of wave breaking, atmospheric blocking, or jets as atmospheric Rossby waveguides. This includes the role of local and remote drivers (e.g., the tropics, Arctic, or stratosphere).
(2) Exploring the links between extreme weather/climate events and the jets and associated linear and non-linear Rossby waves, including wave breaking and/or blocking.
(3) Quantifying model representation of Rossby waves in climate and numerical weather prediction models, including wave propagation and breaking.
(4) Exploring the role of Rossby wave packets on predictability at lead times from medium range (~2 weeks) to seasonal time-scales. This includes blocking and wave propagation.
(5) Analyzing projected future changes in planetary or synoptic-scale Rossby waves, or in their future impacts on weather and climate events.

Convener: Marie Drouard | Co-conveners: Jacopo RiboldiECSECS, Ruth Geen, Volkmar Wirth, Rachel White
Orals
| Wed, 17 Apr, 08:30–12:25 (CEST)
 
Room M2
Posters on site
| Attendance Wed, 17 Apr, 16:15–18:00 (CEST) | Display Wed, 17 Apr, 14:00–18:00
 
Hall X5
Orals |
Wed, 08:30
Wed, 16:15
AS1.33

The field of infrasonic research, the science of low-frequency acoustic waves, has expanded to include acoustic-gravity waves and developed into a broad interdisciplinary field encompassing several academic disciplines of geophysics as well as recent technical and basic scientific developments. The International Monitoring System (IMS) infrasound network for nuclear-test-ban verification and regional infrasound arrays deployed around the globe have demonstrated their capacity for detecting and locating various natural and anthropogenic disturbances. Infrasound and acoustic-gravity waves are capable of traveling up to thermospheric altitudes and over enormous ranges, where the wind and temperature structure controls their propagation. Recent studies have offered new insights on quantitative relationships between infrasonic observations and atmospheric dynamics, opening a new field for atmospheric remote sensing.

New studies using lidar, radar, microwave spectrometer, and mesospheric airglow observations complemented by satellite measurements help better determine the interaction between atmospheric layers and the influence of atmospheric waves on the mean flow. It is expected that further developing multi-instrument platforms will improve gravity wave parameterizations and enlarge the science community interested in operational infrasound monitoring. In a higher frequency range, the infrasound monitoring system also offers unique opportunities to provide, in near-real time, continuous relevant information about natural hazards with high societal impact, such as volcanic eruptions, surface earthquakes, meteoroids, and bright fireballs.

We invite contributions on recent studies characterizing infrasound sources or atmospheric phenomena using complementary technologies. We particularly encourage presentations utilizing acoustic waves to probe the atmosphere at both small and large scales. Results and advances in acoustic propagation modeling, signal processing and machine learning applications are also welcome. Another focus is on derived data products and services for civilian and scientific applications as well as on innovative instrumentation, which also encompasses sensors attached to moving or elevated platforms such as balloons. We also invite seismo-acoustic studies on the coupled Earth’s crust – ocean – atmosphere system and, in particular, on the ionospheric manifestations of physical processes in the ocean and in the solid Earth.

Convener: Alexis Le Pichon | Co-conveners: Patrick HupeECSECS, Alain Hauchecorne, Gunter Stober, Sven Peter Näsholm
Orals
| Tue, 16 Apr, 10:45–12:30 (CEST)
 
Room M2
Posters on site
| Attendance Mon, 15 Apr, 10:45–12:30 (CEST) | Display Mon, 15 Apr, 08:30–12:30
 
Hall X5
Posters virtual
| Mon, 15 Apr, 14:00–15:45 (CEST) | Display Mon, 15 Apr, 08:30–18:00
 
vHall X5
Orals |
Tue, 10:45
Mon, 10:45
Mon, 14:00
CL2.4

ENSO and its interactions with other tropical basins are the dominant source of interannual climate variability in the tropics and across the globe. Understanding the dynamics, predictability, and impacts of ENSO and tropical basins interactions, and anticipating their future changes are thus of vital importance for society. This session invites contributions regarding all aspects of ENSO and tropical basins interactions, including: dynamics, multi-scale interactions; decadal and paleo variability; theoretical approaches; ENSO diversity; global teleconnections; impacts on climate, society and ecosystems; seasonal forecasting and climate change projections of tropical mean state changes, ENSO and its tropical basins interactions. Studies aimed at evaluating and improving model simulations of ENSO, the tropical mean state and the tropical basins interactions basin are especially welcomed.

Co-organized by AS1/NP2/OS1
Convener: Nicola MaherECSECS | Co-conveners: Dietmar Dommenget, Yann Planton, Sarah Ineson, Fred Kucharski
Orals
| Fri, 19 Apr, 08:30–12:30 (CEST), 14:00–15:45 (CEST)
 
Room 0.49/50
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
 
Hall X5
Orals |
Fri, 08:30
Thu, 16:15
AS1.35 EDI

Mountains cover approximately one-quarter of the total land surface on the planet, and a significant fraction of the world’s population lives in their vicinity. Orography critically affects weather and climate processes at all scales and, in connection with factors such as land-cover heterogeneity, is responsible for high spatial variability in mountain weather and climate. Due to this high complexity, monitoring and modeling the atmosphere and the other components of the climate system in mountain regions is challenging both at short (meteorological) and long (climatological) time scales. This session is devoted to a better understanding of weather and climate processes in mountain and high-elevation areas around the globe, as well as their modification induced by global environmental change.

We welcome contributions describing the influence of mountains on the atmosphere on meteorological time scales, including terrain-induced airflow, orographic precipitation, land-atmosphere exchange over mountains, forecasting, and predictability of mountain weather. Contributions connected with the TEAMx research programme (http://www.teamx-programme.org/) are encouraged.

Furthermore, we invite studies that investigate climate processes and climate change in mountain areas and its impacts on dependent systems, based on monitoring and modeling activities. Particularly welcome are contributions that merge various sources of information and reach across disciplinary borders (atmospheric, hydrological, cryospheric, ecological, and social sciences) and that connect to the Elevation-Dependent Climate Change (EDCC) working group of the Mountain Research Initiative (see https://www.mountainresearchinitiative.org/activities/community-led-activities/working-groups).

Co-organized by CL4
Convener: Stefano Serafin | Co-conveners: Maria Vittoria GuarinoECSECS, Sven Kotlarski, Douglas Maraun, Anna NapoliECSECS
Orals
| Tue, 16 Apr, 16:15–17:55 (CEST)
 
Room M2
Posters on site
| Attendance Wed, 17 Apr, 10:45–12:30 (CEST) | Display Wed, 17 Apr, 08:30–12:30
 
Hall X5
Orals |
Tue, 16:15
Wed, 10:45
AS1.36 EDI

The aviation meteorology session will focus on 1) general issues of atmospheric sciences and 2) specifically the use of Uncrewed Aircraft Systems (UAS).
The aviation meteorology session will focus on observations and NWP model applications related to fog, clouds, contrails, ground-based icing and precipitation, and short-range forecasting of weather conditions associated with aviation operations. Abstracts for all areas of aviation meteorology, including Polar region, high altitude conditions, as well as airport environments, can be submitted to this session. Work on aviation meteorology parameters such as visibility, icing, gusts and turbulence, as well as fog and precipitation, will be considered for this session. Topics related to In-situ observations obtained from aircraft, UAS, balloons, and supersites, remote sensing retrievals of meteorological parameters from satellites, radars, lidars, and MicroWave Radiometers (MWRs), as well as other emerging technological platforms, and predictions of meteorological parameters from the numerical weather prediction models will be considered highly related to the goals of this session.
Uncrewed Aircraft Systems (UAS) are an emerging technology, significantly expanding observational capabilities in atmospheric and related sciences. This expansion is enabled by the increased availability and deployment of UAS. This session invites abstracts discussing scientific contributions in atmospheric sciences using various UAS platforms, including fixed-wing UAS, multicopters, and tethered balloon/kite systems (TBS) etc. The topics can include presentations on the development of novel UAS platforms and instrumentation, recent measurement efforts leveraging UAS systems, deployment of UAS to enhance the weather and climate prediction networks, data analysis and synthesis from past UAS field campaigns, and other scientific interpretations of UAS-based datasets to improve process understanding, numerical model prediction, data assimilation and parameterization development.

Convener: Ismail Gultepe | Co-conveners: Norman Wildmann, Wayne Feltz, Andreas PlatisECSECS, D. D. Turner, Maria KezoudiECSECS, Paul Williams
Orals
| Tue, 16 Apr, 14:00–15:45 (CEST)
 
Room M2
Posters on site
| Attendance Wed, 17 Apr, 10:45–12:30 (CEST) | Display Wed, 17 Apr, 08:30–12:30
 
Hall X5
Posters virtual
| Wed, 17 Apr, 14:00–15:45 (CEST) | Display Wed, 17 Apr, 08:30–18:00
 
vHall X5
Orals |
Tue, 14:00
Wed, 10:45
Wed, 14:00
ERE2.1 EDI

Wind and solar power are the predominant new sources of electrical power in recent years. Several countries or regions regularly exceed 100% of variable renewable energy in their grids. By their very nature, wind and solar power, as well as hydro, tidal, wave and other renewable forms of generation are dependent on weather and climate. Modelling and measurement for resource assessment, site selection, long-term and short term variability analysis and operational forecasting for horizons ranging from minutes to decades are of paramount importance.
The success of wind power means that wind turbines are increasingly put in sites with complex terrain or forests, with towers extending beyond the strict logarithmic profile, and in offshore regions that are difficult to model and measure. Major challenges for solar power are notably accurate measurements and the short-term prediction of the spatiotemporal evolution of the effects of cloud field and aerosols. Planning and meteorology challenges in Smart Cities are common for both.
For both solar and wind power, the integration of large amounts of renewable energy into the grid is another critical research problem due to the uncertainties linked to their forecast and to patterns of their spatio-temporal variabilities.
We invite contributions on all aspects of weather dependent renewable power generation, e.g.:
• Wind conditions (both resources, siting conditions and loads) on short and long time scales for wind power development.
• Long term analysis of inter-annual variability of solar and wind resource
• Typical Meteorological Year and probability of exceedance for wind and solar power development,
• Wind and solar resource and atlases.
• Wake effect models and measurements, especially for large wind farms and offshore.
• Performance and uncertainties of forecasts of renewable power at different time horizons and in different external conditions.
• Forecast of extreme wind events and wind ramps.
• Local, regional and global impacts of renewable energy power plants or of large-scale integration.
• Dedicated wind measurement techniques (SODARS, LIDARS, UAVs etc.).
• Dedicated solar measurement techniques (pyranometric sensors, sun-photometer, ceilometer, fish-eye cameras, etc.) from ground-based and space-borne remote sensing.
• Tools for urban area renewable energy supply strategic planning and control.
Other related topics will be considered by the conveners.

Co-organized by AS1
Convener: Xiaoli Larsén | Co-conveners: Gregor Giebel, Somnath Baidya Roy, Philippe Blanc, Petrina PapazekECSECS
Orals
| Thu, 18 Apr, 08:30–12:30 (CEST)
 
Room 0.96/97
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
 
Hall X4
Posters virtual
| Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X4
Orals |
Thu, 08:30
Thu, 16:15
Thu, 14:00
CL3.1.1 EDI

This session explores climate change, extremes, processes and their impacts at regional to local scales, and the tools employed to investigate these phenomena. In particular, we welcome submissions advancing the state-of-the-art in the development and application of high-resolution models (convection-permitting, grid spacing ≤ 4 km) and high-resolution sub-daily data sets. This also includes high-resolution data sets for the land-surface including urban areas, hydrology, vegetation or similar, and their impacts on local-scale climate change and extremes.

The session aims to bring together, amongst others, numerical modellers, the observational community and CORDEX-FPS participants, with the aim of advancing understanding of the aforementioned topics. Of particular interest are new insights which are revealed through high-spatiotemporal-resolution modelling or data sets. For example: convective extremes, physical mechanisms, fine-scale and feedback processes, differences in climate change signal, scale-dependency of extremes, interactions across scales and land-atmosphere interactions. Further, we welcome studies that explore local scale climate change in a variety of contexts whether they be past, present or future change. Studies that move towards an earth system approach – through incorporating coupled oceans, hydrology or vegetation – are especially encouraged.

Additional topics include, though are not limited to:
-- Mesoscale convective systems and medicanes
-- Event-based case studies (including surrogate climate change experiments or attribution)
-- Approaches for quantifying uncertainty at high resolutions including multi-model ensemble and combined dynamical-statistical approaches such as emulators
-- High-resolution winds and their impacts
-- Convection, energy balance and hydrological cycle including vegetation and cities
-- Model setup and parametrization, including sensitivity to resolution, land surface and dynamics
-- Tropical convection and convective processes at local to regional scale
-- Model evaluation and new evaluation metrics/methods
-- Physical understanding of added value over coarser models
-- Severe storms including supercell thunderstorms and hailstorms
-- The roles of natural and internal variability

Co-organized by AS1
Convener: Merja Tölle | Co-conveners: Lorenzo Sangelantoni, Emanuela Pichelli, Douglas Maraun, Puxi LiECSECS
Orals
| Tue, 16 Apr, 08:30–12:30 (CEST), 14:00–15:45 (CEST)
 
Room 0.14
Posters on site
| Attendance Wed, 17 Apr, 10:45–12:30 (CEST) | Display Wed, 17 Apr, 08:30–12:30
 
Hall X5
Orals |
Tue, 08:30
Wed, 10:45

AS2 – Boundary Layer Processes

AS2.1 EDI

Driven by atmospheric turbulence, and integrating surface processes to free atmospheric conditions, the Atmospheric Boundary Layer (ABL) plays a key role not only in weather and climate, but also in air quality and wind/solar energy. It is in this context that this session invites theoretical, numerical and observational studies ranging from fundamental aspects of atmospheric turbulence, to parameterizations of the boundary layer, and to renewable energy or air pollution applications. Below we propose a list of the topics included:

- Observational methods in the Atmospheric Boundary Layer
- Simulation and modelling of ABL: from turbulence to boundary layer schemes
- Stable Boundary Layers, gravity waves and intermittency
- Evening and morning transitions of the ABL
- Convective processes in the ABL
- Boundary Layer Clouds and turbulence-fog interactions
- Micro-Mesoscale interactions
- Micrometeorology in complex terrain
- Agricultural and Forest processes in the ABL
- Diffusion and transport of constituents in the ABL
- Turbulence and Air Quality applications
- Turbulence and Wind Energy applications

Convener: Carlos Yagüe | Co-conveners: Jielun Sun, Xabier Pedruzo BagazgoitiaECSECS
Orals
| Mon, 15 Apr, 08:30–12:30 (CEST)
 
Room 1.85/86
Posters on site
| Attendance Mon, 15 Apr, 16:15–18:00 (CEST) | Display Mon, 15 Apr, 14:00–18:00
 
Hall X5
Posters virtual
| Mon, 15 Apr, 14:00–15:45 (CEST) | Display Mon, 15 Apr, 08:30–18:00
 
vHall X5
Orals |
Mon, 08:30
Mon, 16:15
Mon, 14:00
AS2.2 EDI

Urban Boundary Layer (UBL) Dynamics is determined by city morphology, latent and sensible heat fluxes (including anthropogenic heat), and interactions with rural surroundings. The physical processes in such UBLs are characterized by great strong spatial and temporal heterogeneity, and have the potential to affect societally relevant issues like human thermal comfort, air quality, aviation operations and energy supply.
The goal of this session is to highlight research work and promote discussions on this often underrepresented aspect of urban meteorology and climatology. Hence, we invite and encourage contributions on the following topics:

- Numerical modeling of urban boundary layer dynamics at all scales (from regional to street level)
- Observational methods in the UBL: field campaigns and remote sensing (e.g., flux towers, LIDAR, drones)
- Wind tunnel experiments
- Interaction between local circulations (e.g., UHIC, thermal circulation in complex terrain, sea/lake breeze) and the built environment
- Role of turbulent fluxes and impact of turbulence on wind flow
- Intra-canopy and canyon ventilation
- Impact of urban vegetation (e.g., street trees) on wind flow
- Urban air quality (e.g., pollutant transport and dispersion)
- Urban wind energy potential

Co-organized by CL2/ERE2/NP6
Convener: Aldo BrandiECSECS | Co-conveners: Andrea ZonatoECSECS, Beatriz SanchezECSECS, Francisco Salamanca, Alberto Martilli
Orals
| Mon, 15 Apr, 14:00–15:45 (CEST)
 
Room 1.85/86
Posters on site
| Attendance Tue, 16 Apr, 10:45–12:30 (CEST) | Display Tue, 16 Apr, 08:30–12:30
 
Hall X5
Orals |