Seasonal Variability of Shallow Cumuliform Snowfall: A CloudSat Perspective

Spaceborne radar observations from CloudSat have provided scientifically compelling global snowfall analyses in recent years, including the ability to partition snowfall events into different modes based on underlying cloud morphology. This study will present recent results from a seasonal near-global analysis of cumuliform snowfall production, thus highlighting CloudSat's ability to discern important seasonal snowfall signatures of convectively-generated snowfall. Obvious regional Northern Hemispheric fluctuations in cumuliform snowfall over the high latitude oceanic regions are linked to transient sea ice and marine cold air outbreak occurrence. The North Atlantic Ocean region near Greenland stretching to the far eastern Barents Sea show distinct seasonal peaks in shallow convective snowfall production and is identified as the most prolific cumuliform snowfall production zone in the Northern Hemisphere. Other Northern Hemispheric oceanic regions show strong seasonal peaks with differential phases based on sea ice cover. CloudSat also distinguishes subtle cumuliform snowfall signatures over the Greenland Ice Sheet that display a markedly different seasonal pattern than nearby oceanic regions. While the Northern Hemisphere shows the most compelling seasonal cycle, Southern Hemispheric regions will also be highlighted, including further subtle seasonal cumuliform snowfall signatures over Antarctica. Comparisons with ERA-Interim convective snow datasets will also be presented to illustrate relative uniformity in the seasonal cumuliform snowfall cycle, but will also highlight regional differences in quantitative snowfall estimates between the two datasets. Finally, the interannual variability of shallow cumuliform snowfall will also be presented for the entire CloudSat data record.