Development of rotating shadowband spectral radiometers and GCM radiation code test data sets in support of ARM. Technical progress report, September 15, 1990--September 14, 1991

Three separate tasks are included in the first year of the project. Two involve assembling data sets useful for testing radiation models in global climate modeling (GCM) codes, and the third is concerned with the development of advance instrumentation for performing accurate spectral radiation measurements. Task 1: Three existing data sets have been merged for two locations, one in the wet northeastern US and a second in the dry western US. The data sets are meteorological data from the WBAN network, upper air data from the NCDC, and high quality solar radiation measurements from Albany, New York and Golden, Colorado. These represent test data sets for those modelers developing radiation codes for the GCM models. Task 2: Existing data are not quite adequate from a modeler`s perspective without downwelling infrared data and surface albedo, or reflectance, data. Before the deployment of the first CART site in ARM the authors are establishing this more complete set of radiation measurements at the Albany site to be operational only until CART is operational. The authors will have the site running by April 1991, which will provide about one year`s data from this location. They will coordinate their measurements with satellite overpasses, and, to the extent possible, with radiosonde releases, in order that the data set be coincident in time. Task 3: Work has concentrated on the multiple filter instrument. The mechanical, optical, and software engineering for this instrument is complete, and the first field prototype is running at the Rattlesnake Mountain Observatory (RMO) test site. This instrument is performing well, and is already delivering reliable and useful information