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WINCE
The Winter Cloud Experiment (WINCE) took place from January 23 to February 13, 1997. During WINCE, an instrumented NASA ER-2 high altitude research aircraft will be flown to learn more about detecting clouds from space in winter conditions. WINCE will provide important data with which scientists can improve cloud detection for future satellite instruments such as the MODerate resolution Imaging Spectroradiometer (MODIS). This NASA research instrument, scheduled for launch in mid-1998 as part of Mission to Planet Earth, will assess earth climate trends of which clouds are such an important component. WINCE is jointly hosted by the University of Wisconsin's Space Science Engineering Center and the 115 Fighter Wing, Wisconsin Air National Guard, at Truax Field which will provide necessary faciliites for supporting the NASA ER-2 research aircraft operations. Madison-based Persoft is providing communications equipment to facilitate remote data transfer to and from SSEC computers, about 5 miles away from Truax Field. Persoft specializes in PC-to-host software and wireless network connectivity solutions. UW scientists Steve Ackerman, William Smith and Paul Menzel will head the scientific analysis of the data set, along with NASA scientists Dorothy Hall, Jim Spinhirne and Jim Wang of the Goddard Space Flight Center near Washington, DC. Their research findings will be applied to cloud detection algorithms for the MODIS and other future satellite instruments. "The high altitude nature of the ER-2 (20 km or 65000 feet) is a key element of WINCE. It allows our instruments to make cloud measurements much as they would from a satellite platform. That makes it possible for us to improve our cloud detection capability before the satellite is ever launched," says Ackerman. During WINCE, multispectral radiometric measurements of clouds and the earth will be made by the MODIS Airborne Simulator (MAS), the High-resolution Interferometer Sounder (HIS) and the Microwave Imaging Radiometer (MIR) remote sensing instruments on the ER-2. The measurements combine observations of the microwave, infrared, and visible energy from clouds, atmosphere and earth into a single measurement that can be used to analyze the physical mechanisms important for weather prediction and climate change. Signatures of clouds over snow-covered ground are revealed using reflectance and temperature data derived from these measurements. "In a visible image, both clouds and snow-covered terrain are highly reflective, so they're hard to tell apart," Paul Menzel explained. "In the infrared, cold clouds and cold terrain emit roughly the same thermal energy. Only with multispectral imaging can we hope to separate clouds from snow and ice-covered terrain." Cloud height measurements f! rom the Cloud Lidar System (CLS) onboard the ER-2 can verify the position and thickness of clouds in the radiometric data. That data, when combined with the radiometric measurements, allows UW scientists to examine the underlying signature of the cloud itself. Science Objectives: 1. Cloud detection/properties over snow/ice background 2. Snow detection 3. MAS/HIS absolute calibration comparison 4. SSEC ground-based instrumentation overflight 5. ADEOS underflights For more information, link to "http://cimss.ssec.wisc.edu/wince/wince.html" [Summary provided by WINCE]