G3.1/CR1.80/GD3.11Glacial Isostatic Adjustment, Mantle Viscosity and Ice Sheet Fluctuations (co-organized)
|Convener: M. Poutanen | Co-Conveners: W. Fjeldskaar , V. Klemann , H. Steffen , B. Vermeersen|
Glacial isostatic adjustment (GIA), the response of the Earth to past and present-day fluctuations of glaciers, ice caps, and ice sheets, generates large and measurable changes to sea level, crustal motion, especially the land uplift, and the Earth's gravitational field. Studies on GIA provide also valuable information on past history of ice masses and on Earth rheology. Furthermore, GIA contributes substantially to related mass-transport phenomena, such as present-day hydrological and oceanographic changes. In these cases, the GIA signal must be modelled and removed in order to isolate the other processes.
Scientific investigations of GIA started in the early 18th century in Fennoscandia, and since then various data have been collected, e.g. relative sea-level (RSL), tide gauges records, leveling, GPS, absolute and relative gravity measurements, and nowadays also data from satellite missions. GIA modeling has undergone a huge improvement since its beginning. Nowadays with the computational power, 3D spherical models based on different techniques are mainly in use. Appropriate regional models also exist, which may allow the inclusion of crustal structures such as sedimentary basins and faults for selected special investigations such as post-glacially induced earthquakes.
In this session, we invite papers, which focus on the determination of the mantle viscosity and its impact on GIA phenomena around the world. Furthermore, we welcome contributions directly addressing observations, modelling of GIA and the inferences regarding glacial history and Earth rheology. In particular, applications of GRACE-gravity data and the uncertainties introduced by an imprecisely-known GIA response are of relevance to this session. This session is also a venue to present recent results of the Dynamics of Quaternary Climate (DynaQlim) project and of COST Action ES0701 Improved Constraints on Models of GIA.
Invited speaker: Larry Cathles (Cornell University)