Latest status of Tsho Rolpa and Imja Tsho glacial lakes, Nepal, following the Gorkha Earthquake, 25th April 2015

May 22, 2015

The recent earthquakes in Nepal on the 25th April and 12th May 2015 and many aftershocks have led to concerns being expressed about the stability of two glacial lakes in Nepal – Tsho Rolpa in Rolwaling, and Imja Tsho in the Solukhumbu. Given Prof. John Reynolds’ long association with the Rolwaling community (back to September 1994), they requested help not only with respect to the severe damage done to the village of Beding (largely destroyed) but also with respect to their major worries over Tsho Rolpa.

New satellite data acquired after the first earthquake across the affected areas was made public through the Google Earth Crisis Maps portal and permitted John to undertake a review of the impact of the earthquakes on these two lakes. He has produced a pro bono publico ‘Statement on the Status of Tsho Rolpa and Imja Tsho after the Gorkha Earthquake, Nepal, 25th April 2015’, which has been provided to the Director General of the Department of Hydrology and Meteorology (DHM), Kathmandu. He has responded very appreciatively to the assistance provided. The Statement has also been sent to the Chargé d’affaires at the Embassy of Nepal in London and directly to Rolwaling Sherpas in Nepal and several other interested parties internationally. A PDF copy of the Statement is attached hereto for general access. [Download pdf]

In short, there was no evidence on the new satellite imagery of any detrimental impacts from the two major earthquakes and associated aftershocks and neither of the two glacial lakes poses any greater hazard than before the quakes. John’s aborted field inspection of Tsho Rolpa this month has been postponed now until the autumn. A revised assessment of the glacial hazards at Tsho Rolpa will be produced after the monsoon.

Picture: The terminal moraine complex at Tsho Rolpa, Rolwaling, Nepal, as seen in an extract of a panchromatic image acquired on 29th April 2015 and provided by Google Earth Crisis Maps. Image © Google Earth Digital Globe/CNES/Astrium 2015.