Aerosols and Ice Albedo


Carl Egede Bøggild, Rune Solberg, Andy Hodson, Borgar Aamaas, Øivind Due Trier, The University Centre in Svalbard (UNIS), NORWAY

ABSTRACT

We all know that the Greenland ice sheet melts in a warmer climate. However, enhanced melting is not only caused by warmer air temperatures but can also occur if the surface albedo is changed. And, a minor change in surface albedo will alter the surface energy balance similar to multiple degree of warming air temperatures. So, to analysis of changes in the surface albedo could also explain some of the thinning of glaciers and ice caps seen presently. From ice core studies we know that the industrial era has resulted in significant amounts of Black Carbon (BC) transported to the ice sheet. And, observations in combination with theoretical studies reveal that even the very small concentrations of BC in the Arctic Ocean snow are sufficient to alter the surface albedo. However, the theoretical framework for modelling BC effects on glacier ice does not exist. To quantify the effect of BC on the ice surface we need to quantify the way it mixes and distributes with other aerosols deposited. Recent field results show that the most important factor controlling the overall albedo is the way micro-organisms flocculate aerosols on the melting ice surface into mm size “nodules”. We will present observations and results from the relation between aerosols and the resulting surface albedo.