Cloud-top height determination using ATSR data

A method for computing cloud-top heights using multiangle satellite data has been developed. By exploiting the dual-angle capability of the ERS-1 Along Track Scanning Radiometer (ATSR), cloud-top heights can be determined to a nominal accuracy of ± 1 km. The method uses a spatial correlation function to determine the “best-fit” between the nadir and forward images of any channel. The resulting horizontal shifts are then converted to cloud-top heights using a simple, but accurate, approximation to the ATSR view geometry. The technique is presented, and some examples of cloud top height determination are given. The possibility of determining cloud top winds using this technique is explored.