CR4.2/CL4.14/OS1.16Mass and energy balance of snow and ice and drivers of Greenland ice sheet mass loss (co-organized)
|Convener: Willem Jan van de Berg | Co-Conveners: Thomas Mölg , Bradley Markle , Winnie Chu|
The theme of this combined session is the mass and energy balance of snow and ice with a particular focus on Greenland where also other climatic forcings are important.
The first focus is laid on surfaces processes in glaciated areas in general. The session targets mass and energy exchange processes controlling spatial and temporal variations in surface melting and accumulation. Results from field studies, remote sensing analyses and numerical models of surface layer meteorology, surface energy fluxes, accumulation and ablation are within the scope of this session. Surface mass and energy fluxes of snow and ice bodies are closely coupled with each other through snow and surface topography metamorphism, albedo changes, melt and refreeze processes. Some of these processes, e.g. refreezing, are extremely difficult to quantify leading to uncertainties in the mass balance of glaciers and ice sheets. The need for improved methods for determining their mass and energy balance is further enhanced by the remoteness of many areas where they form important phenomena of the natural environment.
The second focus of this session is the recent mass loss of the Greenland Ice Sheet, which accounts for one quarter of current sea level rise. The majority of the mass loss is concentrated at the ice sheet margin due to the acceleration and thinning of outlet glaciers. Oceanic and atmospheric warming have been suggested as the dominant trigger of such changes. Yet the mechanisms controlling the ice response to external forcing (i.e. oceanic, atmospheric) and internal dynamics (i.e. subglacial hydrology, basal topography) are not well constrained. Recent advances in observation and modeling have illuminated surface changes and important processes at the bedrock, atmosphere, and ocean interfaces. Paleoclimate data provides context for recent climate changes and glacial responses, while ice sheet modeling helps to identify the underlying dynamics. This session brings together studies related to Greenland dynamics from oceanography, glaciology and paleoclimatology to examine the complementarity of ideas and approaches across scientific disciplines.