Sunday, April 21, 2013

2012-13 accumulation update

The 2012-13 wet season on Quelccaya began in earnest ~1 November, when the glacier surface reached its lowest height for the year. A snowy interval at the end of September may have marked the seasonal change in larger-scale circulation, yet this snow all ablated by the end of October and was not preserved.

As of 1 April, net accumulation for the season amounted to ~1.7 meters of snow. This is the least accumulation measured on this date for our 10-year period of record. Only slightly more snowfall had accumulated by this date during the 2009-10 season, one that ended by mid-April and was followed by the greatest ablation we have observed (>0.7 m lowering).

In another month or so the wet-dry season transition will be underway, and we will have a more comprehensive perspective on 2012-13 accumulation. The actual mass addition (water equivalence) will not be known until we are on-site for fieldwork; plans are being made to dig a massive snowpit, for sampling and observations back to 2009-2010 accumulation!