RAP scientists are conducting research
related to the formation and prediction of snow and freezing drizzle
in support of improved methods of detecting and forecasting these
conditions at airports. Airport ground deicing operations are significantly
effected by both snow and freezing precipitation (rain and drizzle),
thus improved detection and forecasts of these conditions will increase
both the safety and efficiency of airline and airport operations.
This work has been primarily funded by the FAA and directed through
their Winter Weather Research Product Development Team (WWRPDT).
A primary product developed by this PDT
has been the Weather Support to Deicing
Decision Making (WSDDM) system. This system provides real-time
and 30 minute nowcasts of snowfall conditions at the airport on
a single, integrated display. A key component of the system is the
use of liquid equivalent snowgauges to provide deicing operators
a real-time estimate of the actual snowfall rate. Currently, only
visibility based snow intensities are available operationally from
the National Weather Service. Research conducted by this PDT has
shown that visibility can often be misleading when trying to estimate
liquid equivalent snowfall rate and may have been a factor in previous
ground deicing accidents (Rasmussen et al. 1999, Rasmussen et al.
2000). The WSDDM system provides a real-time snowfall estimate based
on liquid equivalent rate to alert ground deicing users regarding
this hazardous "high visibility - high snowfall rate" condition.
Research Lead: Roy Rasmussen
Alternate Lead: Chuck Wade
Related Links: The
Relationship Between Snowfall Rate and Visibility - presented
by Roy Rasmussen, J. Vivekanandan and Jeff Cole