European Geosciences Union Assembly 2022

B3.2 Present and future global vegetation dynamics and carbon stocks from observations and models

May 23, 13:20 -14:50
(Co-)Convener: Ana Bastos

The terrestrial vegetation carbon balance is controlled not just by photosynthesis, but by respiration, carbon allocation, turnover (comprising litterfall, background mortality and disturbances) and wider vegetation dynamics. Observed, and likely future, changes in vegetation structure and functioning are the result of interactions of these processes with atmospheric carbon dioxide concentration, climate and human activities. The quantification and assessment of such changes has proven extremely challenging because of a lack of observations at large scales and over the long time periods required to evaluate trends.
Thus, our current understanding of the environmental controls on vegetation dynamics and properties, and, in turn, their impact on carbon stocks in biomass and soils, is limited. The behaviour of vegetation models regarding many of the processes mentioned above remains under-constrained at scales from landscape to global. This gives rise to high uncertainty as to whether the terrestrial vegetation will continue to act as a carbon sink under future environmental changes, or whether increases in autotrophic respiration or carbon turnover might counteract this negative feedback to climate change. For instance, accelerated background tree mortality or more frequent and more severe disturbance events (e.g. drought, fire, insect outbreaks) might turn vegetation into carbon sources. Likewise, understanding how these shifts in dynamics will influence forest composition is crucial for long-term carbon cycle projections.
Uncertainties and/or data gaps in large-scale empirical products of vegetation dynamics, carbon fluxes and stocks may be overcome by extensive collections of field data and new satellite retrievals of forest biomass and other vegetation properties. Such novel datasets may be used to evaluate, develop and parametrize global vegetation models and hence to constrain present and future simulations of vegetation dynamics. Where no observations exist, exploratory modelling can investigate realistic responses and identify necessary measurements. We welcome contributions that make use of observational approaches, vegetation models, or model-data integration techniques to advance understanding of the effects of environmental change on vegetation dynamics, tree mortality and carbon stocks and fluxes at local, regional or global scales and/or at long time scales.

CL4.2 Climate change in the Mediterranean region: understanding the processes, assessing the impacts, designing adaptation and mitigation strategies

May 26,2022 08:30 - 11:05
(Co-)Convener: Ana Bastos

Adapting to climate change in the Mediterranean region represents a key socio-economic and environmental challenge. Different levels of exposure and vulnerability as well as different projected changes characterize the Mediterranean region. Understanding the past, characterizing the present and modelling the future are therefore essential steps to estimate the risks, assess the impacts of climate change, and identify potential adaptation and mitigation strategies. This multidisciplinary MedCLIVAR session encourages contributions from a broad range of disciplines and topics, e.g. dealing with: dynamics and processes of the climate system; sectoral impacts of climate change; climate change adaptation and mitigation; innovative methods and approaches in climate science. The session focuses on all time scales from paleoclimate to future model projections as well as on all relevant socio-economic sectors.

CL3.2.6 Climate extremes, biosphere and society: impacts, cascades, feedbacks, and resilience

May 27, 2002 08:30 - 11:46
(Co-)Convenver: Markus Reichstein, Dorothea Frank

Extreme climate and weather events, associated disasters and emergent risks are becoming increasingly critical in the context of global environmental change and interact with other stressors. 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. This session explores the linkages between extreme climate and weather events, 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? We welcome empirical, theoretical and modelling studies from local to global scale from the fields of natural sciences, social sciences, humanities and related disciplines.