When a DOW is deployed, it collects fine-scale data from within a snowstorm and displays features that can't be seen with more distant radars.
The DOW radars are dual polarization, says Wurman, which means that they send out both horizontally- and vertically-oriented energy. By looking at differences in the energy bounced back from these horizontal and vertical beams, scientists can learn more about the snowflakes, ice, rain and snow pellets in snowbands.
"NSF's dual-polarization DOW radars offer an important new avenue toward better understanding this intense winter weather phenomenon affecting the Great Lakes region," says Brad Smull, program director in NSF's Division of Atmospheric and Geospace Sciences, which funds the DOWs and the LLAP project.
The DOWs measure Doppler winds, snow intensity, and properties related to whether snow is dense, comprised of pellets, or formed from loose collections of traditional six-sided snowflakes. A storm's snow crystal type plays a major role in whether lake-effect snowbands drop a few inches of snow--or more than two feet.
"Understanding snow type is critically important," says Wurman.
The DOWs collect data that will be used to determine how LLAP snowbands intensify and weaken, and move across a region. The scientists are right behind.
"Instead of waiting for snowbands to come to us," says Wurman, "we and the DOWs are going to them."
After forecasting likely snowband events, Steiger, Wurman and colleagues and the DOW drive to one of more than 30 sites near Lake Ontario, Lake Erie, and the Tug Hill Plateau to monitor LLAP snowbands.
During the past week, scientists deployed the DOW to four locations near Oswego and Rochester to study intense snowbands. The bands dropped snow at up to four inches per hour, with final totals of more than two feet.
Initial findings are that intense st
|Contact: Cheryl Dybas|
National Science Foundation