An Evaluation Of Cold Season Precipitation Microphysical Properties From A Ground-Based Perspective

Abstract:

Snowfall plays a key role in the global hydrologic cycle and can have substantial impacts on the environmental, economic, and social sectors ranging from water resource management to climate change. As a result of these ramifications, the ability to detect and measure falling snow at the surface is of great importance. Currently, accurate global surface snowfall measurements are not possible due to the limitations of ground-based instrumentation coupled with the uncertainty in spaceborne retrievals. The recently launched NASA Global Precipitation Measurement (GPM) mission core observatory opens up the potential for near-global real-time, accurate satellite retrievals of snowfall, however additional research is necessary to fully understand snowfall properties and allow for the ability to produce the algorithms for such retrievals.

This study seeks to investigate the microphysical properties of snowfall from a ground-based perspective using data collected during the NASA GPM Cold-season Precipitation Experiment (GCPEx) that took place in southern Ontario, Canada during January and February of 2012. Data collected from the two-dimensional video disdrometer (2DVD) and Particle Size Velocity (PARSIVEL-2) disdrometer are analyzed to determine how the microphysical properties of snowfall including particle size distributions as well as mass-diameter relationships, effective bulk density, and fall speed vary in differing precipitation conditions including light, moderate, and heavy snow as well as multiple storm types including synoptic, lake enhanced, and lake effect events. Relationships between observed microphysical parameters and coincident multi-wavelength radar observations will be examined.