Division V: Cryosphere, Atmosphere and Climate
Division Head: Anais Orsi
The cryosphere, here primarily referring to ice sheets, glaciers, snow and sea ice, is a key component of the Earth’s climate system.
The cryosphere interacts with the climate system in complex, non-linear ways, exhibiting significant large-scale feedback mechanisms that operate in both directions. For instance, changes in global albedo due to reduced snow and ice cover can amplify climate change. Large-scale land ice melt affects sea level, and meltwater fluxes also have profound impacts on ocean salinity, density and circulation, and, vice versa, ocean circulation affects marine melting of ice shelves and glaciers. Cryospheric feedbacks also play a role in polar amplification and global climate sensitivity.
Due to significant climate shifts, the Earth has undergone cycles of glaciation and deglaciation, with ice sheets and glaciers serving as valuable archives of past climate conditions. In particular, ice cores from Greenland, Antarctica and high-altitude glaciers provide detailed records of past climate and environmental changes including changes in water cycle, aerosol deposition, natural forcings (including solar and volcanic activity), and global atmospheric composition. On the other hand, Earth System models offer valuable tools for elucidating the interactions, responses and roles of the global cryosphere in the Earth System.
This division explores how the cryosphere interacts with the global climate system across large spatial and temporal scales, emphasizing the need for a more holistic perspective rather than focusing on a single component of the cryosphere (thus contrasting to other IACS divisions). A primary focus is on paleoclimate reconstructions from ice cores and other cryospheric proxies, alongside global-scale links and feedbacks between ice sheets, glaciers, snow, and sea ice as a system and the Earth’s climate, using both observations and large-scale modeling. It aims to promote collaborative efforts and discussions among cryosphere, atmosphere and climate scientists including fostering partnerships and collaboration with the Scientific Committee on Antarctic Research (SCAR), Climate of the Cryosphere (WRCP/CLIC), the Paleoclimate Modelling Intercomparison Project (PMIP), with the IUGG Commission on Climate and Environmental Change (CCEC), the IAMAS International Commission on Climate (ICCL), and with the International Partnerships in Ice Core Drilling (IPICS).