A new study of ice mass loss in 650 Himalayan glaciers over the past 40 years has revealed accelerating ice loss. The study recent extracted digital elevation models from declassified spy films which were compared with recent ASTER stereo imagery to quantify ice loss for the periods 1975–2000 and 2000–2016. The glaciers included in the study comprising approximately 34% of the total glacierized area in the region, or roughly 55% of the total glacial ice volume. The observed annual mass losses suggest that of the total ice mass present in 1975, about 87% remained in 2000 and 72% remained in 2016. The results also indicate that the average rate of ice loss was twice as rapid in 2000-2016 compared to 1975-2000.
Acceleration of ice loss across the Himalayas over the past 40 years, J. M. Maurer, J. M. Schaefer, S. Rupper and A. Corley, Science Advances 19 Jun 2019: Vol. 5, no. 6, eaav7266 DOI: 10.1126/sciadv.aav7266