Improved derivation of cloud motion winds from triple AVHRR and HIRS

An improved technique is feasible for derivation of cloud motion winds by using pairs of infrared images from three of the NOAA polar orbiting satellites. Relatively short time intervals between observations in conjunction with global coverage twice a day, high spatial resolution and radiometric sensitivity of the NOAA radiometers make such pairs superior to any geosynchronous satellite even at low and middle latitudes, while providing the only means of direct measurements of wind vectors in Arctic or Antarctic. Height assignment which is proven to be the greatest source of error in the current techniques is accomplished by quasi-synchronous measurements at two different satellite zenith angles. Both these advantages are examined on the basis of data from the proof-of-the concept triple of the NOAA-9,-10,-12