Field Report: July 27, 2018

We were up in the basin on Monday and Tuesday to survey points, fly the drone and recover some of our instruments. Unfortunately, the two backup gages are covered by several meters of ice. We still hope to get them back by the end of the season. There is a lot of ice perched high up in the basin, probably related to the disintegration of the floating tongue, which produced a lot of freely moving ice.

Our preliminary post-drainage DEM suggests that the water went down to ~387 m above sea level (pre-drainage water level was 442.5 m). For the initial MC volume calculations, I estimated a post-drainage water elevation in the range between 385 and 365 m. The true value turned out to be outside this range, explaining our overestimation of water volume and peak level.

Correcting this number yields a new volume estimate that corresponds to 90% of the 2016 volume rather than 103%. Rerunning the model with the updated volume estimate predicts discharge curves and peak levels close to their observed equivalents, which makes me hopeful for the prediction of future events.