3:30 PM - 4:45 PM
[ACG24-P20] Mass balance fluctuation of Qaanaaq Ice Caps and its vicinity in northeastern Greenland
Keywords:Greenland, mass balance, climate change, ice cap
We have estimated surface mass balance of five ice caps in northern Greenland by a mass balance model constructed by Hock (1999). The model takes temperature index method for calculating ablation. The model computes spatial variation of surface mass balance for the ice caps. The 100m - gridded DEM and surface condition of the ice cap, derived from modified ALOS (Advanced Land Observing Satellite) data, were used for the model calculation. The climate data as input of the model was air temperature and precipitation at Thule climate station (TCS, 77.2N, 68.4W), which is one of the long-term running climate stations in Greenland situated about 100 km south to Qaanaaq. The air temperature at TCS has been increasing after 1990.
The calculation has been done for Qaanaaq Ice Cap (QIC) since 1980s. The mass balance of QIC has been negative since 1980s. The mass balance calculation by the model has been done for other four ice caps for 2006 – 2009 and compared with the surface elevation change reported by Saito et al. (2015). Ice caps situated in coastal area show less negative mass balance than those situated inland. The ice caps situated in coastal area show higher albedo (Saito, et al., 2015), which is possibly because higher fraction of precipitation falls as snow.