3.5.2 Reanalysis data
To further investigate the influence of atmospheric circulation on
patterns of snow cover depletion in the whole study area, we downloaded
ERA-Interim records of daily air temperatures and mean sea level
pressure (MSLP) for central Asia from the European Centre for
Meteorology and Forecasting, between 1990 and 2017 (Dee et al., 2011).
ERA-Interim is produced by combining observational data with previous
information from a forecast model in 12-hourly analysis cycles, and we
chose it over other reanalysis products in view of its temporal coverage
and relatively fine grid sampling of 0.75°x0.75°. We employed the daily
analysis product with observations at 6:00:00 UTC, corresponding to noon
local time, and averaged them to monthly, spring and winter values to
calculate temperature anomalies over the reference climate period.