3.6 Correlation analysis
We investigated links between snow cover variability, atmospheric
circulation and temperatures through correlation analysis, assessing the
strength of relationships using Pearson’s correlation coefficient (r),
and evaluating significance (p) using a two-tailed student test. We
compared winter/spring indices with DSCD and DPSCD at separate elevation
ranges and basins, and per pixel in the case of DSCD. To assess the
influence of temperatures, we also compared winter/spring indices with
temperature anomalies and temperature anomalies with snow cover
variables. Temperatures from stations and ERA-Interim reanalysis between
2000 and 2017 were used for this test. Before this operation, data were
detrended to isolate the inter-annual fluctuations (Panagiotopoulos et
al., 2005). This analysis was also performed for each basin as a whole
and at separate elevation ranges, with temperatures from each weather
station and ERA-Interim grid cells in the study area.