Friday, June 7, 2013

Final pre-fieldwork accumulation update

During the month of May, snow depth at Quelccaya summit has increased in about half of all years since 2004. By the beginning of June the dry season has typically begun, and until early August, snowfall is only associated with occasional, relatively-brief winter precipitation events.

For the accumulation season 2012-13, snowdepth on 1 June amounted to 1.70 meters, increased slightly by a mid-May snowfall event. This accumulation season is thus second only to 2009-10 (1.64 m) in terms of low snowfall, and considerably below the median 1 June depth of 2.06 m. In contrast, La Niña year 2007-08 saw the greatest snowdepth on 1 June, at 2.40 m.

This update will be the last on accumulation until after our fieldwork, when among other activities we will measure density and determine the water equivalent accumulation for 2012-13. This will provide a more accurate measure of precipitation, and put the accumulation season into a proper longer-term context. Hopefully, we will encounter easy digging!

Wednesday, June 5, 2013

Preparing for fieldwork!

A component of our forthcoming 2013 fieldwork will involve high-accuracy GPS measurements, uploading data to Scripps for processing, downloading calculated coordinates, and then re-occupying dozens of points comprising a strain net on the glacier which was established and surveyed in 1983. In preparation, Dave Chadwell & Carsten Braun are in San Diego this week testing GPS receivers, a BGAN terminal, laptops, charging systems, and Iridium phones. Multiple redundancies will hopefully insure that things go smoothly on the ice cap!