[A-CG39] Science in the Arctic Region

[ACG39-P12] Recent surface melt on the Greenland Ice Sheet derived from multi spaceborne sensors

*Rigen Shimada¹, Masahiro Hori² (1.Japan Aerospace Exploration Agency, 2.University of Toyama)

Keywords:Greenland Ice Sheet, GCOM-C, GCOM-W

Recent mass loss of the Greenland Ice Sheet had been affected by the expand of melt period for snow albedo reduction. Surface melt causes the enhancement of the snow metamorphism and the snow grain size gaining. And glacial microbe cultivation is also accelerated because they could live in the liquid water. Therefore, it is important to detect the snow melt onset and its period. In previous studies, there were many methods for detecting the snow melt using remote sensing technique using passive microwave radiometer, optical sensor and thermal infrared sensor. These methods had advantages and disadvantages originated from spatial resolution, observation frequency and atmospheric/weather conditions. In this study, we developed the Greenland Ice Sheet surface melt monitoring system called JASMES Greenland Ice Sheet Monitor. In this system the passive microwave, thermal and optical sensors were used in the melt detection algorithm. This system shows the melt area and extent variation using Terra/MODIS, Aqua/MODIS and GCOM-W/AMSR2 data after 2013. From 2018, the GCOM-C/SGLI data had been integrated in this system. In 2019, the massive surface melt of ice sheet occured in early August. The melt extent reached 72 percent of the whole region of ice sheet in 10 days running average and it was maximum melt after 2013. In 2019, August monthly mean albedo derived from MODIS was minimum during recent 20 years. Especially snow area albedo was minumum even compared with 2012. In further work, we are planning to investigate the cause of the melt and effect for the albedo reduction.