Examination and Implication of Historical Snowfall Trend in Central North America under Recent Climate Change

Studying long-term historical snowfall change can provide useful information for understanding climate change, managing water resource and assessing climate model performance, especially at regional scale where topographic difference can often play an important role in shaping regional climate and water availability. In this study, we empirically examined annual snowfall changes collected from more than 600 stations from 1971 to 2017 in central North America, a region with high contrast of topographic complexities. Our results showed wide spread of decreasing snowfall trends with increasing trends shrinking in the Great Plains and emerging in certain ranges of the Rocky Mountains, which were not reported by previous studies and may have revealed more recent snowfall trends in the region. The results from multiple linear regression analysis showed that while snowfall trends in the entire study region varied based on average annual snowfall and winter temperature, trends in mountain region statically associated with the multiply of elevation and average annual snowfall, which highlighted the influence of topography on snowfall trend variation. Examination of moisture indicated that water availability issues may have persisted in their own directions regardless of the observed snowfall trends in both mountain and plain regions, and further studies will be needed to better predict future scenarios.