Friday October 21 CSL Meeting

Validation of MERRA-2, MERRA-Land, and ERA-Interim Snow Depth Quantities in Eurasia

Presenter: Daniel Vecellio
Time: Friday 21 October, 2:00-3:00 p.m.
Location: 805 O&M

Abstract: The presence of snow plays a large role in the exchange of energy between the surface and atmosphere and controlling ground temperatures during the winter season. While snow cover extent can easily be obtained using satellite data, snow depth measurements, which must be made directly, are a bit more rare, especially on the vast landmass that is Eurasia. In this study, reanalysis products are verified against in-situ measurements of snow depth to determine whether these spatially-continuous products are of acceptable quality to be used in lieu of observations as initial conditions in future modeling studies. NASA's Modern-Era Retrospective Analysis for Research (MERRA)'s second version (MERRA-2) and land-specific version (MERRA-Land) are used as well as the European Centre for Medium-Range Weather Forecasting's Interim Reanalysis (ERA-Interim). Results show that while MERRA-2 and ERA-Interim both show high correlations and comparable mean absolute errors, the latter's ability to better capture trends in monthly snow depth values from 1980-2011 make it the more suitable product to use as a source of snow depth data.

Locations of statistically significant trends in February snow depth for a) MERRA-2 (top left), b) MERRA-Land (top right), c) ERA-Interim (bottom left), and d) observations (bottom right).