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The Laboratory for CLiMMATE works with the development and calibration of atmospheric and cloud models using data from radar and radiometer measurements. It is currently working with models for stratus clouds, cirrus ice crystals, atmospheric attenuation and precipitation measurements.
Our work includes the development of algorithms for the calibration of the atmospheric models to better retrieve the physical and radiative characteristics of the atmosphere. This includes water vapor content, vertical air motion, turbulence, liquid water content, and raindrop distribution for clouds and/or precipitation. We also look at the atmospheric attenuation suffered by the radar signal as it travels through the clear atmosphere due to water vapor and oxygen gases. This attenuation varies, among other factors, with frequency, radar scanning angle, air temperature and pressure.
We currently employ data collected with the UMass Cloud Profiling Radar System (CPRS) operating at 33GHz and 95GHz, a NOAA wind profiler, operating at 2.8GHz, microwave radiometers and NWS radiosondes. In addition, we are developing an atmospheric doppler radar for weather applications. This work is sponsored by NASA and NSF.
Understanding the role of clouds in the Earth’s heat budget and the radiation transfer processes is vital for global climate models and meteorological studies. This centers' research comprises the areas of remote sensing of the atmosphere, including rain and clouds, using microwave sensors such as radars and radiometers at various frequencies.
Microwave remote sensing has the advantage over optical remote sensing in that the information do not depend on the illumination by the Sun, therefore radars can "see" during the night as well as during the day. Radars can also penetrate clouds and provide information about the microphysical properties of clouds and rain. Several physical parameters important to weather prediction and climate modeling such as mean drop size diameter, and rain rate distribution can be retrieve from the information provided by these sensors.
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