Fig. 5: SSI was negatively correlated with temperature in all seasons and positively correlated with precipitation, except in spring months.
From: Recent decreases in snow water storage in western North America
Correlation analysis determine climate attributions of SSI changes, per ecoregion through the 64-year record. Average temperature, total precipitation, and annual snow fraction were compared to annual \(\overline{{{{{{\rm{SSI}}}}}}}\). Variables were averaged spatially across each ecoregion. Hydroclimatic variables significantly correlated (p ≤ 0.05) with annual \(\overline{{{{{{\rm{SSI}}}}}}}\) (1950–2013) for EPA Level III ecoregions for a annual average, b fall season (September, October, November); c winter season (December, January, February), and d spring season (March, April, May); red = negative correlation, blue = positive correlation (r < −0.5 or r > 0.5).
