Union-wide
Inter- and Transdisciplinary Sessions
Disciplinary sessions AS–GM
Disciplinary sessions GMPV–TS

Session programme

CL

CL – Climate: Past, Present & Future

Programme group chairs: Irka Hajdas, Didier Roche

MAL4a
CL 2020/2021 Milutin Milankovic Medal Lectures & 2020 Arne Richter Award for Outstanding ECS Lecture
Conveners: Didier Roche, Irka Hajdas
Presentations
| Tue, 20 Apr, 10:30–12:30 (CEST)
DM3
Division meeting for Climate: Past, Present & Future (CL)
Conveners: Irka Hajdas, Didier Roche
Tue, 20 Apr, 13:30–14:30 (CEST)
DM3
Division meeting for Climate: Past, Present & Future (CL)
Conveners: Irka Hajdas, Didier Roche
Tue, 20 Apr, 13:30–14:30 (CEST)
MAL4b
CL 2020/2021 Hans Oeschger Medal Lectures & Division Outstanding ECS Award Lecture
Conveners: Irka Hajdas, Didier Roche
Presentations
| Tue, 20 Apr, 15:00–17:00 (CEST)
MAL1b
EGU 2020/2021 Alfred Wegener Medal Lectures
Conveners: Alberto Montanari, Helen Glaves
Presentations
| Wed, 21 Apr, 11:30–14:30 (CEST)
NET9

Public information:
The representatives of the Early-Career Scientist (ECS) and outreach team of the Climate division welcome all ECS during this networking event. The event is based on Gathertown Game and the objective is to create an opportunity for new young scientists to meet leading scientists in climate, enhance their network and have some feedback about career life in climate science....

This networking event will be organized via the online platform gather.town (https://gather.town/i/wwsPoATP). It is a video-calling space that lets multiple people hold separate conversations in parallel, walking in and out of those conversations (just as in real life) with your own “avatar”. You do not need any prior experience with gather.town (but for those eager: it always helps to check out online resources and tips & tricks). The best tip we found: You can make your Avatar dance by pressing “Z” on your keyboard (use a Google Chrome or Firefox browser).

Join us and have fun.
Convener: Carole NehmeECSECS | Co-convener: Janina J. Nett
Thu, 22 Apr, 18:00–19:00 (CEST)
NET27

Public information:
Please join on the Gather.Town (follow the link) and let's meet in the Lounge
Convener: Irka Hajdas | Co-conveners: Janina J. Nett, Carole NehmeECSECS
Wed, 21 Apr, 18:00–19:00 (CEST)

CL1 – Past Climates

CL1.1 EDI

This session aims to place recently observed climate change in a long-term perspective by highlighting the importance of paleoclimate research spanning the past 2000 years. We invite presentations that provide insights into past climate variability, over decadal to millennial timescales, from different paleoclimate archives (ice cores, marine sediments, terrestrial records, historical archives and more). In particular, we are focussing on quantitative temperature and hydroclimate reconstructions, and reconstructions of large-scale modes of climate variability from local to global scales. This session also encourages presentations on the attribution of past climate variability to external drivers or internal climate processes, data syntheses, model-data comparison exercises, proxy system modelling, and novel approaches to producing multi-proxy climate field reconstructions.

Convener: Sarah S. EgglestonECSECS | Co-conveners: Stella AlexandroffECSECS, Hugo Beltrami, Steven Phipps, Andrea Seim
vPICO presentations
| Fri, 30 Apr, 09:00–12:30 (CEST)
CL1.2

Modelling past climate states, and the transient evolution of Earth’s climate remains challenging. Time periods such as the Paleocene, Eocene, Pliocene, the Last Interglacial, the Last Glacial Maximum or the mid-Holocene span across a vast range of climate conditions. At times, these lie far outside the bounds of the historical period that most models are designed and tuned to reproduce. However, our ability to predict future climate conditions and potential pathways to them is dependent on our models' abilities to reproduce just such phenomena. Thus, our climatic and environmental history is ideally suited to thoroughly test and evaluate models against data, so they may be better able to simulate the present and make future climate projections.

We invite papers on palaeoclimate-specific model development, model simulations and model-data comparison studies. Simulations may be targeted to address specific questions or follow specified protocols (as in the Paleoclimate Modelling Intercomparison Project – PMIP or the Deep Time Model Intercomparison Project – DeepMIP). They may include anything between time-slice equilibrium experiments to long transient climate simulations (e.g. transient simulations covering the entire glacial cycle as per the goal of the PalMod project) with timescales of processes ranging from synoptic scales to glacial cycles and beyond. Comparisons may include past, historical as well as future simulations and focus on comparisons of mean states, gradients, circulation or modes of variability using reconstructions of temperature, precipitation, vegetation or tracer species (e.g. δ18O, δD or Pa/Th).

Evaluations of results from the latest phase of PMIP4-CMIP6 are particularly encouraged. However, we also solicit comparisons of different models (comprehensive GCMs, isotope-enabled models, EMICs and/or conceptual models) between different periods, or between models and data, including an analysis of the underlying mechanisms as well as contributions introducing novel model or experimental setups.

Co-organized by BG2/NP1
Convener: Kira Rehfeld | Co-conveners: Heather Andres, Julia Hargreaves
vPICO presentations
| Tue, 27 Apr, 11:00–17:00 (CEST)
ITS3.5/NH3

Extreme events and natural hazards are frequent occurrences on our unstable planet. They are predicted to become more common, severe and costly in the future and this session explores their role in human prehistory and history. In order to understand the potential of contemporary and future extreme events to impact human societies, it is critical to understand the mechanisms of how they may have occurred in the past, and elucidate their effects. This session invites contributions from across relevant disciplines. Global in scope and not limited to specific types of extreme events or natural hazards, we hope to compare and contrast differing methods and datasets that address the character and role of extreme events in the human past. Ultimately, we also seek to discuss how the evidence base of Pleistocene and Holocene calamities can be brought into play in the discussion about sustainability and disaster risk reduction in the Anthropocene, as well as to explore how extreme events may have shaped our past.

Public information:
Please note that this session is linked to an open special issue in Frontiers in Earth Science. For further information, please visit https://www.frontiersin.org/research-topics/18192/extreme-events-in-human-evolution-from-the-pliocene-to-the-anthropocene or get in touch with the session conveners! The CfP for this special issue is open and we would welcome relevant submissions.
Co-organized by CL1/SM1, co-sponsored by Future Earth
Convener: Felix Riede | Co-conveners: Huw S. Groucutt, Amy Prendergast
vPICO presentations
| Thu, 29 Apr, 09:00–10:30 (CEST)
SSP4.3 EDI

This session will focus on the emerging discipline of Conservation Paleobiology that uses the data from the fossil record and sedimentary archives to inform biodiversity conservation and ecosystem management. Even though humans have altered ecosystems for millennia, direct ecological observations rarely encompass more than the last few decades. At the same time, the accelerating pace of global climate change requires better understanding of the long-term resilience and adaptive capacities of ecosystems facing multiple stressors. The youngest fossil record can offer high-resolution insights into ecosystem change on timescales well beyond the limits of ecological monitoring, enabling the reconstruction of ecological baselines and natural range of variability. Additionally, the pre-Quaternary geologic record provides a series of natural experiments allowing assessment of biotic responses to major environmental perturbations, strengthening the theoretical foundations of conservation science.

We invite presentations offering both the near-time and deep-time perspective on ecological and evolutionary processes operating during times of rapid environmental changes, ranging from the Anthropocene biodiversity crisis to Phanerozoic mass extinction events. We also welcome contributions highlighting potential biases affecting the fossil record by linking stratigraphic, taphonomic and ecological patterns. We hope to stimulate discussion on novel opportunities and limitations of using different types of geohistorical data to address some of the most urgent questions in Conservation Biology.

Co-organized by BG1/CL1, co-sponsored by CPN
Convener: Rafał NawrotECSECS | Co-conveners: Paolo G. Albano, Stefano Dominici, Niklas HohmannECSECS, Vanessa Julie RodenECSECS
vPICO presentations
| Thu, 29 Apr, 15:30–17:00 (CEST)
CL1.6 EDI

The consequences and impact of climate change for ecosystems, landscapes and human societies depend on the rate, duration and nature of change. While paleoclimate archives provide ample records of such climatic variability, a lack of proxy sensitivity, in combination with chronological uncertainties in age models, often make it difficult to identify the actual agents of change for a specific region. A key example is the Younger Dryas (YD), which is expressed in Western Europe as a significant cold period, but also drying, which possibly lagged the cooling by a century or so. Contrary, in Eastern Europe, paleodata suggest that cooling was restricted to winter season, only, whereas summer temperatures were mostly stable. The resulting massive ecosystem change during the YD has been attributed variably to cooling as well as drying and/or possible changes in seasonality.

With significant advances in relative and absolute chronological techniques (e.g., tephrochronology and cosmogenic radionuclide synchronization) which enable the comparison of ecosystem responses on common timescales, as well as an increased proxy understanding and modelling, it is now becoming possible to disentangle the different components of the climate system and compare their responses over continental scales.

Focussing on the last glacial-interglacial cycle we invite contributions that assess, diagnose, model and quantify the agents of climatic change, as well as those that permit new insights into the rates during abrupt transitions. We particularly welcome research (including modelling studies) that address the importance of temperature, hydrological and seasonal changes using archives (e.g., ice core, marine and terrestrial), and those that advance our understanding of the responses of different paleoclimate proxies. A better understanding of both the cause AND effect of past abrupt climate changes and spatio-temporal differences is needed for a better prediction of the consequences of the anthropogenic interference with the climate system.

Convener: Dirk Sachse | Co-conveners: Markus CzymzikECSECS, Michael DeiningerECSECS, Danielle McLeanECSECS, Aurel Perşoiu
vPICO presentations
| Thu, 29 Apr, 13:30–14:15 (CEST)
CL1.7 EDI

The half-century since the first deep ice core drilling at Camp Century, Greenland, has seen extensive innovation in methods of ice sample extraction, analysis and interpretation. Ice core sciences include isotopic diffusion analysis, multiple-isotope systematics, trace gases and their isotopic compositions, ice structure and physical properties, high-resolution analysis of major and trace impurities, and studies of DNA in ice, among many others. Several projects (e.g. Beyond EPICA Oldest Ice) are to surface ice as old as 1.5 million years old from very compressed layers at the very bottom of the Antarctic ice sheet in the coming years. Analysis and interpretation of this ice will bring new challenges, including the potential for in situ processes to impact the climatic signals. Furthermore, a variety of ice cores have been drilled recently in the framework of the ICE MEMORY initiative to preserve environmental and climate information from glaciers threatened by climate change.
This session welcomes all contributions reporting the state-of-the-art in ice coring sciences, including drilling and processing, dating, analytical techniques, results and interpretations of ice core records from polar ice sheets and mid- and low-latitude glaciers, remote and autonomous methods of surveying ice stratigraphy, and related modelling research.

Co-organized by CR2
Convener: Thomas Blunier | Co-conveners: Anja Eichler, Vasileios Gkinis, Rachael Rhodes
vPICO presentations
| Mon, 26 Apr, 13:30–17:00 (CEST)
CL1.8 EDI

The pacing of the global climate system by orbital variations is clearly demonstrated in the timing of e.g. glacial-interglacial cycles. The mechanisms that translate this forcing into geoarchives and climate changes continue to be debated. We invite submissions that explore the climate system response to orbital forcing, and that test the stability of these relationships under different climate regimes or across evolving climate states (e.g. mid Pleistocene transition, Pliocene-Pleistocene transition, Miocene vs Pliocene, and also older climate transitions). Submissions exploring proxy data and/or modelling work are welcomed, as this session aims to bring together proxy-based, theoretical and/or modelling studies focused on global and regional climate responses to astronomical forcing at different time scales in the Phanerozoic.

Co-organized by SSP2
Convener: Stefanie Kaboth-BahrECSECS | Co-conveners: Anne-Christine Da SilvaECSECS, Mingsong Li, Huanchun Wu, Christian Zeeden
vPICO presentations
| Thu, 29 Apr, 15:30–17:00 (CEST)
CL1.9

Over the last 1.5 Myr the rhythm of glaciations changed from a 40 kyr world to a 100 kyr world, known as the Mid-Pleistocene Transition (MPT). This transition does not follow directly from Milankovitch theory. Against the background of the start of a new deep drilling project in Antarctica (Beyond-Epica) covering this period in a few years from now, we encourage the broader paleo community to show their latest results on the mechanisms underlying the transition. We invite presentations on changes in proxies over this time as well as model studies providing insight in the processes and drivers of the Earth climate system over the MPT.

Convener: Roderik van de Wal | Co-conveners: Margareta Hansson, Eric Wolff
vPICO presentations
| Wed, 28 Apr, 11:45–12:30 (CEST)
SSP2.12 EDI

Polar regions are particularly sensitive to climate variability and play a key role in global climate and environmental conditions through various feedback mechanisms. In this session we invite contributions dealing with all aspects of Phanerozoic (i.e. Cambrian to Holocene) geology from high latitude regions: stratigraphy, paleoenvironment, paleoclimate, and modelling.

Co-organized by CL1
Convener: Madeleine Vickers | Co-conveners: Jennifer M. Galloway, Kasia K. Sliwinska
vPICO presentations
| Wed, 28 Apr, 15:30–17:00 (CEST)
GM7.7 EDI

Mountain and ice sheet glaciations provide an invaluable record for past and present climate change. However, varying geomorphological process-systems, specific glaciological conditions and topography can make regional, intra-hemispheric and global correlations challenging. This problem is further enhanced by ongoing specialisation within the scientific community. Despite such challenges glacier and ice sheet reconstructions remains a crucial palaeo-enviormental proxy.

The primary aim of this session is to evaluate the potential of mountain and ice sheets glaciation records and stimulate further research in this important field of research. Contributions on all relevant aspects are welcomed, for example: (a) glacial landforms and reconstruction of past glaciers/ice sheets, (b) dating techniques and geochronology compilations, (c) glacier dynamics and palaeoclimatic interpretations, or (d) impacts of ecosystems and human evolution/society.

We would in particular like to invite contributions highlighting the specific conditions of mountain glaciations/ice sheet or addressing the relationship and connections between different of their aspects. To address the diversity of glaciations, contributions from high-, middle-, and low-latitude mountain ranges as well as from continental to maritime regions are all welcomed. The time scale of the session will range from Early Pleistocene glaciations to the LGM and Holocene/modern glaciers.

This session has steadily become more popular and attracted contributions from a wide range of research topics and study areas, both with a high diversity of methodological approaches. It has become a platform for everyone interested in the emerging collaborative research network “The Legacy of Mountain Glaciations” and given an opportunity to meet and exchange ideas and expertise.

Co-organized by CL1/CR6
Convener: Danni Pearce | Co-conveners: Stefan Winkler, April Dalton, Lauren KnightECSECS, Giovanni Monegato, Jürgen Reitner
vPICO presentations
| Thu, 29 Apr, 09:00–10:30 (CEST)
CL1.13

The geological record provides insight into how climate processes may operate and evolve in a high CO2 environment and the nature of the climate system during a turnover from icehouse to greenhouse state — a transition that may potentially occur in the near future. In recent years we have seen major advances in many geochemical techniques and an increase in the complexity of Earth System Models. The aim of this session is to share progress in our understanding of global changes occurring during the pre-Quaternary based on the integration of geochemical/paleobotanical/sedimentological techniques and numerical models. Specifically, we encourage submissions describing research in which both model and data approaches are embedded. We invite abstracts that reconstruct Earth’s climate from the Cambrian to the Pliocene, investigate how the interconnections of the key surface reservoirs (vegetation-ocean-atmosphere-cryosphere-biogeochemistry) impact climate, and identify tipping points and thresholds. Pertinent themes may include greenhouse-icehouse transitions and intervals testifying for extreme changes.

Co-organized by SSP2
Convener: Yannick Donnadieu | Co-convener: Gregor Knorr
vPICO presentations
| Thu, 29 Apr, 11:45–12:30 (CEST)
CL1.14

The study of deep-time (pre-Quatrenary) climate evolution is important not only for understanding Earth’s habitable history but also for providing insights to present and future changes of the Earth system. To investigate deep-time climate, several international modelling intercomparsion projects, for example DeepMIP, MioMIP, PlioMIP, have been initiated. All these MIPs pay attention to the Cenozoic climate. However, relatively fewer modelling studies simulate climate in deeper time before the Cenozoic. This session invites works on deep-time climate simulations and reconstructions over the tectonic time scales, including, but not limited to, idealized and comprehensive model simulations, geological, geochemical, and paleontological reconstructions. We wish this session could integrate our knowledge of deep-time climate and environment evolution in the spirit of an integrated Earth system.

Co-organized by BG1/SSP1
Convener: Yongyun Hu | Co-convener: Z.S. Zhang
vPICO presentations
| Thu, 29 Apr, 09:00–11:45 (CEST)
GD1.4 EDI

Processes responsible for formation and development of the early Earth (> 2500Ma) are not well understood and strongly debated, reflecting in part the poorly preserved, altered, and incomplete nature of the geological record from this time.
In this session we encourage the presentation of new approaches and models for the development of Earth's early crust and mantle and their methods of interaction. We encourage contributions from the study of the preserved rock archive as well as geodynamic models of crustal and mantle dynamics so as to better understand the genesis and evolution of continental crust and the stabilization of cratons.
We invite abstracts from a large range of disciplines including geodynamics, geology, geochemistry, and petrology but also studies of early atmosphere, biosphere and early life relevant to this period of Earth history.

Co-organized by AS4/BG5/CL1/GMPV3
Convener: Ria Fischer | Co-conveners: Peter A. Cawood, Nicholas Gardiner, Antoine Rozel, Jeroen van Hunen
vPICO presentations
| Mon, 26 Apr, 11:00–12:30 (CEST)
SSP3.1 EDI

During the past decades numerous sediment records have become available from lakes and paleolakes through shallow and (ICDP) deep drilling. These records have proven to be valuable archives of past climate and environmental change, human activities as well as tectonic and volcanic activity. We invite contributions emphasizing quantitative and spatial assessments of rates of change, causes and consequences of long- and short-term climate variability, impact, magnitude, and frequency of tectonic and volcanic activity as deduced from sedimentological, geochemical, biological, and chronological tools.

Co-organized by CL1/NH5, co-sponsored by IAS
Convener: Hendrik Vogel | Co-conveners: Charline Giguet-Covex, Jasper Moernaut, Marta MarchegianoECSECS, Marina MorlockECSECS
vPICO presentations
| Mon, 26 Apr, 11:00–12:30 (CEST)
CL1.18 EDI

Tree rings are one of nature’s most versatile archives, providing insight into past environmental conditions at annual and intra-annual resolution and from local to global scales. Besides being valued proxies for historical climate, tree rings are also important indicators of plant physiological responses to changing environments and of long-term ecological processes. In this broad context we welcome contributions using one or more of the following approaches to either study the impact of environmental change on the growth and physiology of trees and forest ecosystems, or to assess and reconstruct past environmental change: (i) dendrochronological methods including studies based on tree-ring width, MXD or Blue Intensity, (ii) stable isotopes in tree rings and related plant compounds, (iii) dendrochemistry, (iv) quantitative wood anatomy, (v) ecophysiological data analyses, and (vi) mechanistic modelling, all across temporal and spatial scales.

Co-organized by BG3
Convener: Kerstin Treydte | Co-conveners: Flurin Babst, Giovanna Battipaglia, Elisabet Martinez-Sancho, Jernej Jevšenak
vPICO presentations
| Tue, 27 Apr, 13:30–17:00 (CEST)
CL1.19 EDI

Speleothems and continental carbonates (e.g. travertines, pedogenic, lacustrine, subglacial and cryogenic carbonates) are important terrestrial archives, which can provide precisely dated, high-resolution records of past environmental and climate changes. The field of carbonate-based paleoclimatology has seen (1) continuously improving analytical capacity, producing detailed records of climate variability integrating established as well as novel and innovative techniques. (2) Long-term monitoring campaigns facilitating the interpretation of high-resolution proxy time series from carbonate archives. (3) At the same time proxy-system models can help understanding the measured proxies, by describing processes such as water infiltration, CO2 and carbonate dissolution, and carbonate precipitation and diagenesis. Applied together, advancements in these cornerstones of carbonate related research pave the way towards developing highly reliable quantitative terrestrial climate reconstructions.
Here, we invite contributions that show progress in one of the three outlined domains. We especially welcome integrated and interdisciplinary studies, connecting these branches of carbonate related research in order to better understand the climate system on various time scales.

Co-organized by SSP1
Convener: Jens Fohlmeister | Co-conveners: Andrea Borsato, Gabriella KoltaiECSECS, Sophie WarkenECSECS, Andrea Columbu
vPICO presentations
| Thu, 29 Apr, 09:00–10:30 (CEST)
BG4.3 EDI

Carbonate (bio)minerals have played an essential role in the history of life on Earth, forming one of the most important archives for past climate and environmental change. Geochemical investigations have been crucial for understanding the evolution of microbial habitats and the paleobiology of carbonate biomineralizers since the Precambrian. With this session, we encourage contributions from sedimentology, geochemistry and biology that utilize carbonate (bio)minerals (e.g., microbialites, mollusk shells, and foraminifera) with the aim to reconstruct past environments, seasonality, seawater chemistry, and paleobiology in a wide range of modern to deep time settings, including critical intervals of environmental and climatic change. This includes theoretical or experimental studies of trace element partitioning and isotope fractionation and studies into original skeletal carbonate preservation and diagenetic alteration.

Public information:
13.35 - 13.53h: Stromatolites & the applications of novel isotope systems (chairs: Viehmann & Rodler)
13.53 - 14.19h: Skeletal carbonate archives (chairs: de Winter & Vellekoop)
14.19 - 15.00h: Discussion
Co-organized by CL1/SSP1
Convener: Sebastian ViehmannECSECS | Co-conveners: Niels de WinterECSECS, Alexandra RodlerECSECS, Johan VellekoopECSECS
vPICO presentations
| Thu, 29 Apr, 13:30–15:00 (CEST)

CL2 – Present Climate

CL2.1

Climate services challenge the traditional interface between users and providers of climate information as it requires the establishment of a dialogue between subjects, who often have limited knowledge of each-other’s activities and practices. Increasing the understanding and usability of climate information for societal use has become a major challenge where economic growth, and social development crucially depends on adaptation to climate variability and change.

To this regard, climate services do not only create user-relevant climate information, but also stimulate the need to quantify vulnerabilities and come up with appropriate adaptation solutions that can be applied in practice.

The operational generation, management and delivery of climate services poses a number of new challenges to the traditional way of accessing and distributing climate data. With a growing private sector playing the role of service provider is important to understand what are the roles and the responsibilities of the publicly funded provision of climate data and information and services.

This session aims to gather best practices and lessons learnt, for how climate services can successfully facilitate adaptation to climate variability and change by providing climate information that is tailored to the real user need.
Contributions are strongly encouraged from international efforts (GFCS, CSP, ClimatEurope…); European Initiatives (H2020, ERA4CS, C3S, JPI-Climate…) as well as national, regional and local experiences.

Convener: Alessandro Dell'Aquila | Co-conveners: Carlo Buontempo, Daniela Domeisen, Nube Gonzalez-Reviriego, Verónica Torralba
vPICO presentations
| Thu, 29 Apr, 09:00–11:45 (CEST)
CL2.2 EDI

As the most evident example of land use and land cover change, urban areas play a fundamental role in local to large-scale planetary processes, via modification of heat, moisture, and chemical budgets. With rapid urbanization ramping up globally it is essential to recognize the consequences of landscape conversion to the built environment. Given the capability of cities to serve as first responders to global change, considerable efforts are currently being dedicated across many cities to monitor and understand urban atmospheric dynamics and examine various adaptation and mitigation strategies aimed to offset impacts of rapidly expanding urban environments and influences of large-scale greenhouse gas emissions.

This session solicits submissions from both the observational and modelling communities examining urban atmospheric and landscape dynamics, processes and impacts owing to urban induced climate change, the efficacy of various strategies to reduce such impacts, and techniques highlighting how cities are already using novel science data and products that facilitate planning and policies on urban adaptation to and mitigation of the effects of climate change. Emerging topics including, but not limited to, compounding impacts with urban COVID-19 outbreaks or urban climate informatics, are highly encouraged.

Co-organized by AS2
Convener: Natalie TheeuwesECSECS | Co-conveners: Sorin Cheval, M Georgescu, Hendrik WoutersECSECS
vPICO presentations
| Tue, 27 Apr, 09:00–15:00 (CEST)
CL2.3

Large-scale atmospheric circulation dynamics are the major driver of near surface climatic and environmental variability. Synoptic climatology examines atmospheric circulation dynamics and their relationship with near surface environmental variables. Within synoptic climatological analyses, a wide variety of methods is utilized to characterize atmospheric circulation (e.g., circulation and weather type classification, regime analysis, teleconnection indices). Various linear and non-linear approaches (e.g., multiple regression, canonical correlation, neural networks) are applied to relate the circulation dynamics to diverse climatic and environmental elements (e.g., air temperature, air pollution, floods).

The session welcomes contributions from the whole field of synoptic climatology. This includes application studies for varying regions, time periods (past, present, future) and target variables and in particular contributions on the development and the comparison of methods (e.g., varying circulation type classifications) and conceptual approaches (e.g., circulation types versus circulation regimes).

Co-organized by AS1
Convener: Christoph Beck | Co-conveners: Andreas Philipp, Pedro M. Sousa, Jan Stryhal
vPICO presentations
| Tue, 27 Apr, 15:30–17:00 (CEST)
NH10.4 EDI

High-impact climate and weather events typically result from the interaction of multiple hazards across various spatial and temporal scales. These events, also known as Compound Events, often cause more severe socio-economic impacts than single-hazard events, rendering traditional univariate extreme event analyses and risk assessment techniques insufficient. It is therefore crucial to develop new methodologies that account for the possible interaction of multiple physical drivers when analysing high-impact events. Such an endeavour requires (i) a deeper understanding of the interplay of mechanisms causing Compound Events and (ii) an evaluation of the performance of climate/weather, statistical and impact models in representing Compound Events.

The European COST Action DAMOCLES coordinates these efforts by building a research network consisting of climate scientists, impact modellers, statisticians, and stakeholders. This session creates a platform for this network and acts as an introduction of the work related to DAMOCLES to the research community.

We invite papers studying all aspects of Compound Events, which might relate to (but are not limited to) the following topics:

Synthesis and Analysis: What are common features for different classes of Compound Events? Which climate variables need to be assessed jointly in order to address related impacts? How much is currently known about the dependence between these variables?
Stakeholders and science-user interface: Which events are most relevant for stakeholders? What are novel approaches to ensure continuous stakeholder engagement?
Impacts: What are the currently available sources of impact data? How can they be used to link observed impacts to climate and weather events?
Statistical approaches, model development and evaluation: What are possible novel statistical models that could be applied in the assessment of Compound Events?
Realistic model simulations of events: What are the physical mechanisms behind different types of Compound Events? What type of interactions result in the joint impact of the hazards that are involved in the event? How do these interactions influence risk assessment analyses?

Co-organized by AS4/CL2/HS13
Convener: Jakob ZscheischlerECSECS | Co-conveners: Freya GarryECSECS, Nina Nadine RidderECSECS, Philip Ward, Seth Westra
vPICO presentations
| Wed, 28 Apr, 15:30–17:00 (CEST)
CL2.5 EDI

Predictions of climate from seasonal to decadal time scales and their applications will be discussed in this session. With a time horizon from a few months up to thirty years, such predictions are of major importance to society, and improving them presents an interesting scientific challenge. This session aims to embrace advances in our understanding of the origins of seasonal to decadal predictability, as well as in improving the respective forecast skill and making the most of this information by building and testing new applications and climate services.

The session will cover dynamical as well as statistical predictions (including machine learning methods), and their combination. It will investigate predictions of various climate phenomena, including extremes, from global to regional scales, and from seasonal to multidecadal time scales ("seamless predictions"). Physical processes relevant to long-term predictability sources (e.g. ocean, cryosphere, or land) as well as predicting large-scale atmospheric circulation anomalies associated to teleconnections will be discussed, as will observational and emergent constraints on climate variability and predictability on the seasonal-to-(multi)decadal time scale. Also, the time-dependence of the predictive skill, or windows of opportunity (hindcast period), will be investigated. Analysis of predictions in a multi-model framework, and ensemble forecast initialization and generation, including innovative ensemble approaches to minimize initialization shocks, will be another focus of the session. The session will pay 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 risk assessment, adaptation and further applications.

Co-organized by AS4/HS13/NH1/NP5
Convener: André Düsterhus | Co-conveners: Panos J. Athanasiadis, Leonard BorchertECSECS, Leon Hermanson, Deborah VerfaillieECSECS
vPICO presentations
| Mon, 26 Apr, 09:00–10:30 (CEST)
CL2.6 EDI

Large-scale atmospheric circulation, hydrological cycle and heat/moisture transports are tightly intertwined by global patterns of energy contrasts which are sensitive to multiple forcings and feedbacks. In the tropics, cross-equatorial energy exchanges by the ocean and atmosphere couple Hadley Circulation and Atlantic Overturning circulation, and modulate the low-level mass convergence and the amount of precipitation in the ITCZ and in monsoon regions. In the extra-tropics, Rossby waves affect the distribution of precipitation and eddy activity, shaping the meridional heat transport from the low latitudes towards the Poles.

We invite submissions addressing the interplay between Earth’s energy exchanges and the general circulation using modeling, theory, and observations. We encourage contributions on the forced response and natural variability of the general circulation, understanding present-day climate and past and future changes, and impacts of global features and change on regional climate.

Convener: Roberta D'AgostinoECSECS | Co-conveners: David Ferreira, Valerio Lembo, Piero Lionello
vPICO presentations
| Wed, 28 Apr, 11:45–12:30 (CEST)
HS7.2

The assessment of precipitation variability and uncertainty is crucial in a variety of applications, such as flood risk forecasting, water resource assessments, evaluation of the hydrological impacts of climate change, determination of design floods, and hydrological modelling in general. Within this framework, this session aims to gather contributions on research, advanced applications, and future needs in the understanding and modelling of precipitation variability, and its sources of uncertainty.
Specifically, contributions focusing on one or more of the following issues are particularly welcome:
- Novel studies aimed at the assessment and representation of different sources of uncertainty versus natural variability of precipitation.
- Methods to account for different accuracy in precipitation time series, e.g. due to change and improvement of observation networks.
- Uncertainty and variability in spatially and temporally heterogeneous multi-source precipitation products.
- Estimation of precipitation variability and uncertainty at ungauged sites.
- Precipitation data assimilation.
- Process conceptualization and modelling approaches at different spatial and temporal scales, including model parameter identification and calibration, and sensitivity analyses to parameterization and scales of process representation.
- Modelling approaches based on ensemble simulations and methods for synthetic representation of precipitation variability and uncertainty.
- Scaling and scale invariance properties of precipitation fields in space and/or in time.
- Physically and statistically based approaches to downscale information from meteorological and climate models to spatial and temporal scales useful for hydrological modelling and applications.

Co-organized by CL2/NH1/NP5
Convener: Simone Fatichi | Co-conveners: Alin Andrei Carsteanu, Roberto Deidda, Giuseppe Mascaro, Chris Onof
vPICO presentations
| Fri, 30 Apr, 11:00–12:30 (CEST)
CL2.8

Changes in seasonal timing affect species and ecosystem response to environmental change. Observations of plant and animal phenology as well as remote sensing and modeling studies document complex interactions and raise many open questions.
We invite contributions with cross-disciplinary perspectives that address seasonality changes based on recent plant and animal phenological observations, pollen monitoring, historical documentary sources, or seasonality measurements using climate data, remote sensing, flux measurements or modeling studies. Contributions across all spatial and temporal scales are welcome that compare and integrate seasonality changes, study effects of long-term climate change or single extreme events, emphasize applications and phenology informed decision-making, discuss species interactions and decoupling, advance our understanding of how seasonality change affects carbon budgets and atmosphere/biosphere feedbacks, and integrate phenology into Earth System Models.
We emphasize phenology informed applications for decision-making and environmental assessment, public health, agriculture and forest management, mechanistic understanding of the phenological processes, and effects of changing phenology on biomass production and carbon budgets. We also welcome contributions addressing international collaboration and program-building initiatives including citizen science networks and data analyses.

This session is organized by a consortium representing the International Society of Biometeorology (Phenology Commission), the Pan-European Phenology Network - PEP 725, the Swiss Academy of Science SCNAT, the TEMPO French Phenology Network and the USA National Phenology Network.

Convener: Helfried Scheifinger | Co-conveners: Iñaki Garcia de Cortazar-Atauri, Marie Keatley, Christina Koppe, Yann Vitasse
vPICO presentations
| Wed, 28 Apr, 14:15–17:00 (CEST)
GM8.2 EDI

Arid to sub-humid regions contribute > 40 % to the global land surface and are home of more than 40 % of the world’s population. During prehistoric times many important cultures had developed in these regions. Due to the high sensitivity of dryland areas even to small-scale environmental changes and anthropogenic activities, ongoing geomorphological processes but also the Late Quaternary palaeoenvironmental evolution as recorded in sediment archives are becoming increasingly relevant for geomorphological, palaeoenvironmental and geoarchaeological research. Dryland research is also boosted by methodological advances, and especially by emerging linkages with other climatic and geomorphic systems that allow using dryland areas as indicator-regions of global environmental change.
This session aims to pool contributions from the broad field of earth sciences that deal with geomorphological processes and different types of sediment archives in dryland areas (dunes, loess, slope deposits, fluvial sediments, alluvial fans, lake and playa sediments, desert pavements, soils, paleosols etc.) at different spatial and temporal scales. Besides case studies from individual regions and archives, methodical and conceptual contributions, e.g. dealing with the special role of eolian, fluvial, gravitational and biological processes in dryland environments, their preservation over time in the sedimentary records, and emerging opportunities and limitations to resolve past and current dynamics, are especially welcome in this session.

Co-organized by CL2/SSP1/SSS3
Convener: Hans von Suchodoletz | Co-conveners: Markus Fuchs, Joel Roskin, Abi StoneECSECS, Lupeng Yu
vPICO presentations
| Fri, 30 Apr, 13:30–15:00 (CEST)
HS8.2.3 EDI

Groundwater is the world's most important, best protected and most exploited freshwater resource. It is intensively used by humans. It is also the primary source for drinking water supply and irrigation, hence critical to the global water-food-energy security nexus, especially in dry regions. Groundwater is sensitively to shifts in climate, which changes the hydrological cycle and thus groundwater recharge. Additionally, global changes such as population growth or changes in land use affect groundwater resources, both in terms of quantity and quality. Due to these changes, regions with high water stress are expected to expand globally. Beside regions that have already a water deficit, new regions, such as catchments in Central Europe with continental climate and decreasing precipitation in summer periods are likely to be subjected to water stress. The Mediterranean basin is also expected to become a major hot spot of water stress in the future.
Therefore, groundwater resources, especially in dry regions, need to be managed wisely, protected and especially used sustainably. In this session we invite contributions, which identify new consequences of a changing environment for better future management, protection, and sustainable use of groundwater. This implies adapted modelling techniques, such as coupling climate models with hydrological models, coupling climate models with soil water- and groundwater models. This includes also studies into groundwater quantity and quality changes and recharge mechanisms. In addition, we invite contributions from appropriate field observational studies.

Furthermore, the session asks for contributions that address regional strategies for groundwater sustainability, in detail that (i) unravel the combined action of topography, geology, climate, land use and anthropogenic forcing in controlling regional groundwater availability, quality and sustainability; and (ii) propose new methods (e.g., coupled modelling approaches) for assessing and managing regional groundwater systems in diverse climatic, hydrologic, socio-economic and institutional settings, and accounting for uncertainty; (iii) present appropriate field observational studies; (iv) address uncertainty and limited data availability due to a frequently associated data scarcity issue in dry regions, methodologies, strategies.

Co-organized by CL2
Convener: Martin Sauter | Co-conveners: Irina Engelhardt, Noam Weisbrod, J.C. Maréchal, Xavier Sanchez-Vila, Zhilin GuoECSECS, Taher Kahil, Ting TangECSECS
vPICO presentations
| Tue, 27 Apr, 15:30–17:00 (CEST)
ITS2.11/AS4.12

This session is linked to the Pan-Eurasian EXperiment (PEEX; www.atm.helsinki.fi/peex), a multi-disciplinary, -scale and -component climate change, air quality, environment and research infrastructure and capacity building programme. It is aimed at resolving major uncertainties in Earth system science and global sustainability issues concerning the Arctic, Northern Eurasia and China regions. This session aims to bring together researchers interested in (i) understanding environmental changes effecting in pristine and industrialized Pan-Eurasian environments (system understanding); (ii) determining relevant environmental, climatic, and other processes in Arctic-boreal regions (process understanding); (iii) the further development of the long-term, continuous and comprehensive ground-based, air/seaborne research infrastructures together with satellite data (observation component); (iv) to develop new datasets and archives of the continuous, comprehensive data flows in a joint manner (data component); (v) to implement validated and harmonized data products in models of appropriate spatio-temporal scales and topical focus (modeling component); (vi) to evaluate impact on society though assessment, scenarios, services, innovations and new technologies (society component).
List of topics:
• Ground-based and satellite observations and datasets for atmospheric composition in Northern Eurasia and China
• Impacts on environment, ecosystems, human health due to atmospheric transport, dispersion, deposition and chemical transformations of air pollutants in Arctic-boreal regions
• New approaches and methods on measurements and modelling in Arctic conditions;
• Improvements in natural and anthropogenic emission inventories for Arctic-boreal regions
• Physical, chemical and biological processes in a northern context
• Aerosol formation-growth, aerosol-cloud-climate interactions, radiative forcing, feedbacks in Arctic, Siberia, China;
• Short lived pollutants and climate forcers, permafrost, forest fires effects
• Carbon dioxide and methane, ecosystem carbon cycle
• Socio-economical changes in Northern Eurasia and China regions.
PEEX session is co-organized with the Digital Belt and Road Program (DBAR), abstracts welcome on topics:
• Big Earth Data approaches on facilitating synergy between DBAR activities & PEEX multi-disciplinary regime
• Understanding and remote connection of last decades changes of environment over High Asia and Arctic regions, both land and ocean.

Public information:
This session is linked to the Pan-Eurasian EXperiment (PEEX; www.atm.helsinki.fi/peex), a multi-disciplinary, -scale and -component climate change, air quality, environment and research infrastructure and capacity building program. PEEX is aimed at resolving major uncertainties in Earth system science and global sustainability issues concerning the Arctic, Northern Eurasia and China regions. The PEEX - EGU - 2021 session(s) are dedicated in honor of the memory of Prof. Sergej Zilitinkevich.
Co-organized by BG3/CL2/CR7/GI4
Convener: Markku Kulmala | Co-conveners: Alexander Baklanov, Hanna Lappalainen, Sergej Zilitinkevich (deceased)
vPICO presentations
| Thu, 29 Apr, 09:00–12:30 (CEST)
CL2.12

It has been shown that regional climate change interacts with many other man-made perturbations in both natural and anthropogenic coastal environments. Regional climate change is one of multiple drivers, which have a continuing impact on terrestrial, aquatic and socio-economic (resp. human) environments. These drivers interact with regional climate change in ways, which are not completely understood. Recent assessments all over the world have partly addressed this issue (e.g. Assessment of Climate Change for the Baltic Sea region, BACC (2008, 2015); North Sea Climate Change Assessment, NOSCCA (2011); Canada’s Changing Climate Report, CCCR (2019)).
This session invites contributions, which focus on the connections and interrelations between climate change and other drivers of environmental change, be it natural or human-induced, in different regional seas and coastal regions. Observation and modelling studies are welcome, which describe processes and interrelations with climate change in the atmosphere, in marine and freshwater ecosystems and biogeochemistry, coastal and terrestrial ecosystems as well as human systems. In particular, studies on socio-economic factors like aerosols, land cover, fisheries, agriculture and forestry, urban areas, coastal management, offshore energy, air quality and recreation, and their relation to climate change, are welcome.
The aim of this session is to provide an overview over the current state of knowledge of this complicated interplay of different factors, in different regional seas and coastal regions all over the world.

Co-organized by BG4/HS13/OS2
Convener: Marcus Reckermann | Co-conveners: Ute Daewel, Helena Filipsson, Markus Meier, Markus Quante
vPICO presentations
| Fri, 30 Apr, 15:30–17:00 (CEST)
CL2.13

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; low frequency, decadal and paleo variability; theoretical approaches; ENSO diversity; global teleconnections; impacts on climate, society and ecosystems; seasonal forecasting and climate change projections of ENSO and its tropical basins interactions. Studies aimed at understanding ENSO and its tropical basins interactions in models of a range of complexity are especially welcomed, including analysis of CMIP model intercomparisons.

Co-organized by AS1/NP2/OS1
Convener: Dietmar Dommenget | Co-conveners: Antonietta Capotondi, Daniela Domeisen, Eric Guilyardi
vPICO presentations
| Fri, 30 Apr, 13:30–15:00 (CEST)
CL2.16 EDI

Agriculture is an important sector of any economy of the world. Agriculture productions are highly dependent on the climate change and variability. Changes in hydro-meteorological variables can influence crop yield and productivity at many places. Further, climate change can influence nutrient levels, soil moisture, water availability and other terrestrial parameters related to the agricultural productivity. Changes in the frequency and severity of droughts and floods could pose challenges for farmers and ranchers and threaten food safety. Further, changes in climate can influence meteorological conditions and thus can influence the crop growth pattern. It may also influence irrigation scheduling and water demand of the crops. The effects of climate change also need to be considered along with other evolving factors that affect agricultural production, such as changes in farming practices and technology.

The purpose of the proposed session is to gather scientific researchers related to this topic aiming to highlight ongoing researches and new applications in the field of climate change and agriculture. In this framework, original works concerned with the development or exploitation of advanced techniques for understanding the impact of climate change on agriculture will be invited.

The conveners of this session will encourage both applied and theoretical research in this area.

Co-organized by NH8
Convener: Prashant Kumar Srivastava | Co-conveners: Manika GuptaECSECS, R K Mall, George P. Petropoulos, George Stavroulakis
vPICO presentations
| Mon, 26 Apr, 13:30–15:00 (CEST)
CL2.17

Weather and Climate Services (WCS) involve the production, translation, delivery, and use of science-based information for decision-making. The production of WCS makes use of long-term climate projections, climate and weather predictions from daily to decadal timescales, historical hydrometeorological data, and sectoral models to predict risks of climate impacts to society. These services are developed and delivered in support of (i) climate-sensitive sectors such as agriculture, management of water resource, health, energy and disaster risk reduction, and (ii) developing countries where the vulnerability to climate change and extreme weather events is high. This session, interdisciplinary in nature, aims at showcasing tools, products and methodologies that could be standardized for an operational and innovative system of WCS delivery in developing countries. The session invites contributions that include a) improvements of models and data analysis for WCS; b) engagement with end-users of WCS; c) assessment of the value of WCS’s outcomes and the corresponding impacts on societies and the environment; d) strategies for broad communication of WCS information to multiple audiences; and e) WCS partnerships between multiple stakeholders such as end-users, NGOs, government ministries, policymakers, and the private sector. The session particularly encourages lessons learned and results from different case studies coming from the global South.

Co-organized by AS4/NH1
Convener: Philippe Roudier | Co-conveners: Roberta Boscolo, Pauline Dibi Kangah, Erik Kolstad, Michael Singer
vPICO presentations
| Wed, 28 Apr, 13:30–14:15 (CEST)

CL3 – Future Climate & Anthropocene

CL3.1 – Climate change: from regional to global

CL3.1.1

Regional Climate Models (RCMs) have become fundamental tools to study climate processes and
climate change projections at the regional to local scale, and the COordinated Regional Downscaling EXperiment (CORDEX) has become a central program within the RCM modeling community. This session accepts papers on a wide range of topics pertaining the field regional climate modeling and applications, including: recent developments in RCM science; added value of RCMs; applications of RCMs to regional climate change projection; development and application of coupled regional Earth System Models (including interactive atmosphere, ocean, chemistry/aerosol, biosphere and cryosphere components); development and application of convection-permitting RCMs; completion and/or analysis of CORDEX experiments, both single model simulations and multi-model ensembles; completion and/or analysis of experiments within the CORDEX-CORE and CORDEX Flagship Pilot Studies programs; application of RCM output to vulnerability, impacts and adaptation studies; application of RCMs to climate service activities.

Convener: Filippo Giorgi | Co-conveners: Melissa Bukovsky, Ivan Guettler
vPICO presentations
| Mon, 26 Apr, 09:00–12:30 (CEST), 13:30–15:00 (CEST)
CL3.1.2 EDI

Anthropogenic aerosol plays a key role in driving climate anomalies over a range of spatial and temporal scales, both near the emission location and remotely through teleconnections. Aerosols can interact with radiation and clouds, directly and through absorption, microphysics and circulation, and thereby modify the surface and atmospheric energy balance, cloud dynamics and precipitation patterns, and the atmospheric and oceanic circulation. This session addresses progress in understanding the mechanisms and pathways by which aerosols affect regional climate features, overall, over the historical era, and in the near future. We encourage contributions on new model and observation-based approaches to investigate the effects of aerosols on regional decadal climate variability and extremes, tropical-extratropical interactions and teleconnections, and the interplay with modes of variability such as the NAO, AMO, and PDO. Focus studies on monsoon, midlatitude, and Arctic responses, extreme precipitation, circulation changes, daily variability, CMIP6 projections of high and low aerosol futures, and investigations using large ensemble simulations are welcome.

Co-organized by AS3
Convener: Laura Wilcox | Co-conveners: Massimo Bollasina, Bjorn H. Samset, Sabine Undorf
vPICO presentations
| Thu, 29 Apr, 13:30–14:15 (CEST)
CL3.1.3 EDI

In this session, we invite presentations that investigate CMIP6 (or other, similarly co-ordinated) simulations.

Analysis of the Sixth Coupled Model Intercomparison Project (CMIP6) is now well underway. Here, we focus on analyses of coordinated simulations undertaken through, or parallel to, the CMIP protocol, with a particular focus on historical simulations and future projections. We are particularly interested in analyses that involve a role for the North Atlantic region, either in evaluating/describing simulated/projected variability or in the North Atlantic’s remote effect on other regions. We are interested in (multi)model evaluation, mechanisms of variability, as well as impact analysis. Multimodel analyses are especially welcome as are critical comparisons between models and observations.

We invite presentations that investigate CMIP (or similarly co-ordinated) simulations on topics including, but not limited to, the following:

-o- The historical and future evolution of the Atlantic Meridional Overturning Circulation (AMOC)
-o- Projected changes in the strength and location of the jet stream
-o- Atlantic Multidecadal Variability (AMV), including future changes and the role of internally/externally forced variability
-o- Projections or mechanisms of changes in hurricane activity
-o- The drivers and impacts of Arctic ice melt
-o- The hydrological cycle and freshening of the North Atlantic, including “hosing” simulations
-o- Teleconnections between the North Atlantic and remote regions including over land

Co-organized by OS1
Convener: Matthew MenaryECSECS | Co-conveners: Laura Jackson, Juliette Mignot, Jon Robson, Yohan Ruprich-RobertECSECS
vPICO presentations
| Thu, 29 Apr, 11:45–12:30 (CEST)
CL3.1.4

Mediterranean climate is characterized by mild, wet winters and hot, dry summers thus making the interested climatic zones among the most desirable for human inhabitation. Mediterranean climate zones are located in transitional midlatitude regions like the Mediterranean basin area, western North America as well as over small areas of western South America, Southern Africa and southern Australia. This classification based on Koppen-Geiger approach is well suited for identifying and analyzing the impacts of climate change on natural and anthropic ecosystems. The transitional character with sharp spatial gradients makes Mediterranean climate-type zones highly vulnerable to climate change. Future climate projections indicate an intensification of the seasonality over these regions, as well as potential migration of these climate regions towards the poles with the equatorward margins likely replaced by arid climate-type. For all mediterranean climate-type regions, the future is expected to provide large issues to face for biodiversity and water availability, including climate adaptation and mitigation measures.
This session aims bringing together studies on different aspects of climate and climate change focused on the Mediterranean climate-type regions of the world. Physical (including extremes, teleconnections, hydrological cycles) and biogeochemical (including biodiversity) approaches but also social aspects (including impacts and adaptation measures) are welcome, either in terms of observed past changes or future climate projections.

Solicited Speaker will be Prof Don McFarlane - School of Agriculture and Environment, University of Western Australia

Convener: Annalisa Cherchi | Co-conveners: Andrea Alessandri, Annarita Mariotti, James Renwick
vPICO presentations
| Fri, 30 Apr, 09:00–09:45 (CEST)
ITS2.15/CL3.1.7

As highlighted by the UN development goals, climate change is a reality to which we need to adapt. Our ability to effectively address the adaptation issue must come from a communal effort to link our knowledge in different fields and transform it into useful information for stakeholders and policymakers.

Up to now, physical climate modelling and natural hazard impact and risk assessment have been two separate disciplines that have suffered difficulties in communicating and interacting due to different languages and backgrounds. Until recently, climate modellers did not have the capability to generate long-term projections at a spatial and temporal resolution useful for impact studies such as flood risk assessment, soil erosion or urban modelling. With the advent of kilometre-scale atmospheric models, called convection-permitting models CPMs, we are now in a position to bridge the gap between the two communities, sharing knowledge and understanding. Compared to traditional climate models, CPMs improve substantially the representation of sub-daily precipitation characteristics and have a spatial resolution closer to what many impacts modellers, for example hydrologists, need. Several CPM datasets are already available over different parts of the world and more internationally coordinated projects on CPMs, such as the CORDEX Flagship Pilot Study (CORDEX-FPS) and the European Climate Prediction System (EUCP), are already in place. Now is the time to exploit these high-resolution physically-consistent datasets as input for impact studies and adaptation strategies; to foster interdisciplinary collaboration to build a common language and understand limitations and needs of the different fields; to learn together how to provide policymakers with information and practical cases that can be used to design effective measures at the regional level to adapt to climate change as well as to inform mitigation decisions.

This interdisciplinary session invites contributions that address the linkages between high-resolution modellers and users with examples of good practice, storylines and communication to both stakeholders and policymakers.

Co-organized by HS12/NH1
Convener: Giorgia Fosser | Co-conveners: Hayley Fowler, Elizabeth Kendon, Andreas F. Prein
vPICO presentations
| Wed, 28 Apr, 15:30–17:00 (CEST)
CL3.1.8 EDI

Detecting and attributing the fingerprint of anthropogenic climate change in long-term observed climatic trends is an active area of research. Though the science is well established for temperature related variables, the study of other climate indicators including hydrometeorological variables pose greater challenges due to their greater complexity and rarity.

Complementary to this, assessing the extent to which extreme weather events, including compound events, are attributable to anthropogenic climate change is a rapidly developing science, with emerging schools of thought on the methodology and framing of such studies. Once again, the attribution of hydrometeorological events, is less straightforward than temperature-related events. The attribution of impacts, both for long-term trends and extreme events is even more challenging.

This session solicits the latest studies from the spectrum of detection and/or attribution approaches. By considering studies over a wide range of temporal and spatial scales we aim to identify common/new methods, current challenges, and avenues for expanding the detection and attribution community. We particularly welcome submissions that compare approaches, or address hydrometerological trends, extremes and/or impacts – all of which test the limits of the present science.

Convener: Aglae Jezequel | Co-conveners: Seung-Ki Min, Pardeep Pall, Aurélien Ribes
vPICO presentations
| Wed, 28 Apr, 13:30–17:00 (CEST)
CL3.1.9 EDI

One of the big challenges in Earth system science consists in providing reliable climate predictions on sub-seasonal, seasonal, decadal and longer timescales. The resulting data have the potential to be translated into climate information leading to a better assessment of multi-scale global and regional climate-related risks.
The latest developments and progress in climate forecasting on subseasonal-to-decadal and longer timescales will be discussed and evaluated. This will include presentations and discussions of predictions for a time horizon of up to ten years from dynamical ensemble and statistical/empirical forecast systems, as well as the aspects required for their application: forecast quality assessment, multi-model combination, bias adjustment, downscaling, etc.
Following the new WCPR strategic plan for 2019-2029, prediction enhancements are solicited from contributions embracing climate forecasting from an Earth system science perspective. This includes the study of coupled processes, impacts of coupling and feedbacks, and analysis/verification of the coupled atmosphere-ocean, atmosphere-land, atmosphere-hydrology, atmosphere-chemistry & aerosols, atmosphere-ice, ocean-hydrology, ocean-ice, ocean-chemistry and climate-biosphere (including human component). Contributions are also sought on initialization methods that optimally use observations from different Earth system components, on assessing and mitigating the impacts of model errors on skill, and on ensemble methods.
We also encourage contributions on the use of climate predictions for climate impact assessment, demonstrations of end-user value for climate risk applications and climate-change adaptation and the development of early warning systems.

A special focus will be put on the use of operational climate predictions (C3S, NMME, S2S), results from the CMIP5-CMIP6 decadal prediction experiments, and climate-prediction research and application projects (e.g. EUCP, APPLICATE, PREFACE, MIKLIP, MEDSCOPE, SECLI-FIRM, S2S4E, CONFESS).
An increasingly important aspect for climate forecast's applications is the use of most appropriate downscaling methods, based on dynamical or statistical approaches or their combination, that are needed to generate time series and fields with an appropriate spatial or temporal resolution. This is extensively considered in the session, which therefore brings together scientists from all geoscientific disciplines working on the prediction and application problems.

Co-organized by BG2/CR7/HS13/NH1/NP5
Convener: Andrea Alessandri | Co-conveners: Yoshimitsu Chikamoto, Marlis Hofer, June-Yi Lee, Xiaosong Yang
vPICO presentations
| Fri, 30 Apr, 15:30–17:00 (CEST)
CL3.1.10 EDI

In 2015, the UN Sustainable Development Goals and the Paris Agreement on climate recognised the deteriorating resilience of the Earth system, with planetary-scale human impacts constituting a new geological epoch: the Anthropocene. Earth system resilience critically depends on the nonlinear interplay of positive and negative feedbacks of biophysical and increasingly also socio-economic processes. These include dynamics in the carbon cycle, large-scale ecosystems, atmosphere, ocean, and cryosphere that can absorb geophysical shocks (e.g. volcanic eruptions), as well as the dynamics and perturbations associated with human activities.

Maintaining Earth in the Holocene-like interglacial state within which the world’s societies evolved over the past ~10,000 years will require industrialised societies to embark on rapid global-scale socio-economic transformations. In addition to incrementally increasing environmental hazards, there is a risk of crossing tipping points in the Earth system triggering partly irreversible and potentially cascading changes.

In this session we invite contributions on all topics relating to Earth resilience, such as assessing the biophysical and social determinants of the Earth’s long-term stability, negative feedback processes, modelling and data analysis and integration of nonlinearity, tipping points and abrupt shifts in the Earth system, and the potential for rapid social transformations to global sustainability.

Co-organized by BG1/CR7/NP8
Convener: Jonathan DongesECSECS | Co-conveners: David Armstrong McKayECSECS, Sarah Cornell, James Dyke, Ricarda Winkelmann
vPICO presentations
| Mon, 26 Apr, 15:30–17:00 (CEST)
SSS5.1 EDI

Soil organic matter (SOM) is well known to exert a great influence on physical, chemical, and biological soil properties, thus playing a very important role in agronomic production and environmental quality. Globally SOM represents the largest terrestrial organic C stock, which can have significant impacts on atmospheric CO2 concentrations and thus on climate. The changes in soil organic C content are the result of the balance of inputs and losses, which strongly depends on the processes of organic C stabilization and protection from decomposition in the soil. This session will provide a forum for discussion of recent studies on the stabilization and sequestration mechanisms of organic C in soils, covering any physical, chemical, and biological aspects related to the selective preservation and formation of recalcitrant organic compounds, occlusion by macro and microaggregation, and chemical interaction with soil mineral particles and metal ions.

Co-organized by BG3/CL3.1
Convener: César Plaza | Co-conveners: Claire Chenu, Beatrice Giannetta, Claudio Zaccone
vPICO presentations
| Thu, 29 Apr, 14:15–17:00 (CEST)
SSP2.6 EDI

The session asks for well-dated geoarchives that document the physical evidence of the transition from the Late Holocene (Meghalayan) to the Anthropocene. These may include artificial deposits, lake, estuary or marine sediments, peat, speleothems, ice core or biological hosts such as trees or corals, displaying good chronologies. The evidence for an Anthropocene can include transitions in the types and abundance of physical materials, biota, or distinct geochemical signals; ideally the study should provide multiple proxies or consider innovative new techniques in recognising the Anthropocene. We are interested in presentations that show continuous to near continuous records that can extend hundreds or even thousands of years back in time, but should also include comparable analysis through the mid-20th century to near present day. The presentations should explain how, if at all, the Anthropocene can be distinguished in these archives. Studies from any continent will be considered, though presentations on archives from South America and Africa are especially encouraged.

Co-organized by CL3.1/GM12
Convener: Michael Wagreich | Co-conveners: Irka Hajdas, Kira LappéECSECS, Colin N. Waters
vPICO presentations
| Wed, 28 Apr, 14:15–15:00 (CEST)
GM12.7 EDI

Documenting the diversity of human responses and adaptations to climate, landscapes, ecosystems, natural disasters and the changing natural resources availability in different regions of our planet, cross-disciplinary studies in Geoarchaeology provide valuable opportunities to learn from the past. Furthermore, human activity became a major player of global climatic and environmental change in the course of the late Quaternary, during the Anthropocene. Consequently, we must better understand the archaeological records and landscapes in context of human culture and the hydroclimate-environment nexus at different spatial and temporal scales. This session seeks related interdisciplinary papers and specific geoarchaeological case-studies that deploy various approaches and tools to address the reconstruction of former human-environmental interactions from the Palaeolithic period through the modern. Topics related to records of the Anthropocene from Earth and archaeological science perspectives are welcome. Furthermore, contributions may include (but are not limited to) insights about how people have coped with environmental disasters or abrupt changes in the past; defining sustainability thresholds for farming or resource exploitation; distinguishing the baseline natural and human contributions to environmental changes. Ultimately, we would like to understand how strategies of human resilience and innovation can inform our modern strategies for addressing the challenges of the emerging Anthropocene, a time frame dominated by human modulation of surface geomorphological processes and hydroclimate.

Co-organized by BG1/CL3.1/SSP2/SSS3
Convener: Julia MeisterECSECS | Co-conveners: André Kirchner, Guido Stefano MarianiECSECS, Kathleen Nicoll, Hans von Suchodoletz
vPICO presentations
| Wed, 28 Apr, 11:00–12:30 (CEST)

CL3.2 – Climate and Society

ITS2.14/HS12.2 EDI

Nature-based Solutions (NBS) are reframing discussion and policy responses worldwide to environmental challenges. Thus, NBS is of growing implementation, supported namely by the EU political agenda (e.g., green deal), as a way to attain the United Nations (UN) Sustainable Development Goals (SDG), and to reinforce the New Urban Agenda. The NBS concept recognise the importance of nature and outline requirements for a systemic and holistic approach to environmental change, based on an understanding of the structure and functioning of ecosystems, and the social and institutional context within which they are situated. Furthermore, there is a growing recognition that human activities exert pressure on natural resources affecting the ecosystem dynamics and therefore the nexus (synergies and trade-offs) between their different functions and services. However, quantification of existing NBS’ effectiveness, their operationalisation and replication in different environmental settings has not been presented in such a way that allows them to be both widely accepted and incorporated in policy development and in practical implementation to achieve the UN SDGs.
This session aims to discuss and advance knowledge of innovative NBS approaches to face environmental challenges, such as water supply and management, agricultural production and healthy ecosystems, and simultaneously provide better understanding of associated social-ecological interactions, contributing to enhance the scientific basis for sustainable development and resilience.
This session seeks to:
- Better understanding of advantages and disadvantages of NBS to address global environmental and societal challenges;
- Studies on adaptation and mitigation options for the effect of climate change on water provisioning and livelihoods;
- New methods and tools to investigate the role of NBS in the context of environmental change; in particular, the effectiveness of NBS for hydro-meteorological risk reduction at landscape/watershed scale;
- New insights, methodologies, tools and best practices enabling successful implementation and upscaling of NBS in multiple contexts;
- Identifying opportunities for and barriers to NBS within current regulatory frameworks and management practices;
- Presenting overviews and case studies of NBS projects that also involve the private sector and market-based mechanisms;
- NBS towards achieving the Sustainable Development Goals (SDGs).

Co-organized by BG1/CL3.2/NH1/SSS12
Convener: Zahra Kalantari | Co-conveners: Carla FerreiraECSECS, Haozhi PanECSECS, Suzanne JacobsECSECS, Alicia CorreaECSECS, Paulo Pereira
vPICO presentations
| Tue, 27 Apr, 09:00–12:30 (CEST)
BG3.11 EDI

Natural disturbances in forests, including windthrow events, insect infestations, wildfires and droughts have intensified in severity, frequency, and extent over the last few decades, and ongoing climate change is predicted to further accelerate these trends. If disturbance regimes exceed ecosystem resilience thresholds, forests may change to a new permanent state (e.g. turnover of tree species composition) or may convert fully into non-forest ecosystems.

Forest management practices can influence both the resistance and resilience of a forest ecosystem to its disturbances, in terms of outcomes for biodiversity, nutrient cycling, and the biochemical and physical properties of landscapes. Promotion of mixed species forestry, for instance, can increase stand stability against windthrow, and might decrease forests’ vulnerability to insect attacks or drought. Retention of dead wood, on the other hand, is thought to enhance the recovery of forest structure and complexity, as well as above and below-ground diversity. Type, scale and intensity of disturbance events, along with pre- and post-disturbance management practices, may ultimately lead to changes in vegetation dynamics and plant-soil-atmosphere interactions.

In this session, we hope to stimulate scientific exchange among ecological research disciplines, broaden the view on how forest management shapes forest susceptibility to natural disturbances, and draw attention to how management can alleviate post-disturbance effects on ecosystem functioning. We aim to bring together research spanning from tree and soil processes at the microscale to landscape-level dynamics. We invite contributions investigating natural forest disturbances and pre- and post-disturbance management practices from a variety of perspectives, including:
• Vegetation dynamics;
• Micro-meteorology;
• Plant physiology;
• Soil sciences;
• Microbiology.

Contributions based on observational, experimental, and modeling studies as well as reviews and syntheses are welcome.

Co-organized by CL3.2/SSS9
Convener: Mathias MayerECSECS | Co-conveners: Frank Hagedorn, Nadine Ruehr, Lars Vesterdal, Olga Vindušková
vPICO presentations
| Mon, 26 Apr, 15:30–17:00 (CEST)
ITS3.2/BG7

Extreme climate and weather events, associated disasters, geohazards and emergent risks interact with other stressors, especially growing anthropogenic pressures, and are so becoming increasingly critical in the context of global environmental change. They are a potential major threat to reaching the Sustainable Development Goals (SDGs) and one of the most pressing challenges for future human well-being and safety.
This session explores the linkages between extreme climate and weather events, geohazards, associated disasters, societal dynamics and resilience.
Emphasis is laid on 1) Which impacts are caused by extreme climate events (including risks emerging from compound events) and cascades of impacts on various aspects of ecosystems and societies? 2) Which feedbacks across ecosystems, infrastructures and societies exist? 3) What are key obstacles towards societal resilience and reaching the SDGs, while facing climate extremes? 4) What can we learn from past experiences? 5) What local to global governance arrangements best support equitable and sustainable risk reduction?
Nowadays, to answer this last question, the careful application of social media and crowdsourcing (SMCS) begins to make a contribution, notably in the field of geosciences. SMCS have been integrated into crisis and Disaster Risk Management (DRM) for improved information gathering and collaboration across communities, and for collaboratively coping with critical situations. Numerous governments and EU-funded projects have been exploring the implementation and use of SMCS by developing and adopting new technologies, procedures, and applications. The effectiveness of SMCS on European disaster resilience, however, remains unclear, due to the diversity among disaster risk perception and vulnerability. In general, this second part addresses ways to govern and understand the effectiveness of SMCS for Disaster Risk Management and the related Disaster Resilience is focused.
In this session we welcome empirical with practical applications, theoretical and modelling studies from local to global scale from the fields of natural sciences, social sciences, humanities and related disciplines since the creation of novel effective approaches necessitates a coordinated and coherent effort between them.

Public information:
Please note that ERL has opened a Focus issue on Earth System Resilience and Tipping Behavior, closely aligned with this session:

Anthropogenic climate change including the increase of unprecedented climate extremes is not a future threat but is happening now. The ability of the atmosphere, hydrosphere or biosphere to adapt to abrupt changes is very limited within a time-frame meaningful to our present social structures. Consequently, determining the resilience of these earth system components to anthropogenic forcing has become a global concern. The resilience of the system, that is its ability to resist these climate disturbances and to recover from the perturbed state, will be a decaying function of the disturbance intensity. Tipping point dynamics can be used to determine system transition conditions at which the perturbed state is no longer decaying but growing and tipping into a new and potentially stable functional branch of the possible outcomes. In the face of catastrophic changes that might be coming, it is vitally important for policy makers and others to know the conditions at which a tipping point could be reached and exceeded. The earth system is highly nonlinear with many positive and negative feedback interactions so that the tipping behavior is complicated. The complexity raises many open research questions: (1) how to determine the tipping elements? (2) what are the early-warning signals for system transitions? (3) what are the potential domino effects for tipping-cascades of abrupt transitions, and (4) does warming climate increase the risk of triggering tipping points?

https://iopscience.iop.org/journal/1748-9326/page/Focus_on_earth_system_resilience_and_tipping_behavior - please consider submitting an abstract!
Co-organized by CL3.2/HS12/NH10
Convener: Markus Reichstein | Co-conveners: Dorothea Frank, Felix Riede, Jana Sillmann, Stefano Morelli, Sara Bonati, Nathan Clark, Veronica Pazzi
vPICO presentations
| Wed, 28 Apr, 09:00–12:30 (CEST)
HS7.3 EDI

Hydroclimatic conditions and the availability of water resources in space and time constitute important factors for maintaining an adequate food supply, the quality of the environment, and the welfare of inhabitants, in the context of sustainable growth and economic development. This session is designed to explore the impacts of hydroclimatic variability, climate change, and the temporal and spatial availability of water resources on: food production, population health, the quality of the environment, and the welfare of local ecosystems. We particularly welcome submissions on the following topics:

- Complex inter-linkages between hydroclimatic conditions, food production, and population health, including: extreme weather events, surface and subsurface water resources, surface temperatures, and their impacts on food security, livelihoods, and water- and food-borne illnesses in urban and rural environments.
- Quantitative assessment of surface-water and groundwater resources, and their contribution to agricultural system and ecosystem statuses.
- Spatiotemporal modeling of the availability of water resources, flooding, droughts, and climate change, in the context of water quality and usage for food production, agricultural irrigation, and health impacts over a wide range of spatiotemporal scales.
- Intelligent infrastructure for water usage, irrigation, environmental and ecological health monitoring, such as development of advanced sensors, remote sensing, data collection, and associated modeling approaches.
- Modelling tools for organizing integrated solutions for water, precision agriculture, ecosystem health monitoring, and characterization of environmental conditions.
- Water re-allocation and treatment for agricultural, environmental, and health related purposes.
- Impact assessment of water-related natural disasters, and anthropogenic forcings (e.g. inappropriate agricultural practices, and land usage) on the natural environment; e.g. health impacts from water and air, fragmentation of habitats, etc.

Co-organized by CL3.2/NH10/NP8
Convener: George Christakos | Co-conveners: Alin Andrei Carsteanu, Elena Cristiano, Andreas Langousis, Hwa-Lung Yu
vPICO presentations
| Tue, 27 Apr, 09:00–10:30 (CEST)
CR5.4

The global cryosphere with all its components is strongly impacted by climate change and has been undergoing significant changes over the past decades. Glaciers are shrinking and thinning. Snow cover and duration is reduced, and permafrost, in both Arctic and mountain environments, is thawing. Changes in sea ice cover and characteristics have attracted widespread attention, and changes in ice sheets are monitored with care and concern. Risks associated with one or several of these cryosphere components have been present throughout history. However, with ongoing climate change, we expect changes in the magnitude and frequency of hazards with profound implications for risks, especially when these interact with other aspects relating to context vulnerability, exposure, and other processes of biophysical and/or socioeconomic drivers of change. New or growing glacier lakes pose a threat to downstream communities through the potential for sudden drainage. Thawing permafrost can destabilize mountain slopes, and eventually result in large landslide or destructive rock and ice avalanches. An accelerated rate of permafrost degradation in low-land areas poses risk to existing and planned infrastructure and raises concerns about large-scale emission of greenhouse gases currently trapped in Arctic permafrost. Decreased summertime sea ice extent may produce both risks and opportunities in terms of large-scale climate feedbacks and alterations, coastal vulnerability, and new access to transport routes and natural resources. Furthermore, rapid acceleration of outlet glacier ice discharge and collapse of ice sheets is of major concern for sea level change. This session invites contributions across all cryosphere components that address risks associated with observed or projected physical processes. Contributions considering more than one cryosphere component (e.g. glaciers and permafrost) are particularly encouraged, as well as contributions on cascading processes and interconnected risks. Contributions can consider hazards and risks related to changes in the past, present or future. Furthermore, Contributions may consider one or several components of risks (i.e. natural hazards, exposure, vulnerability) as long as conceptual clarity is ensured. Furthermore, cases that explore diverse experiences with inter- and transdisciplinary research, that sought to address these risks with communities through adaptation and resilience building, are also be considered.

Co-organized by CL3.2/NH1, co-sponsored by IACS and IPA
Convener: Christian Huggel | Co-conveners: Carolina Adler, Michael Krautblatter, Gabrielle VanceECSECS, Matthew Westoby
vPICO presentations
| Fri, 30 Apr, 09:00–12:30 (CEST)
EOS3.2