The CAMEX-4 ER-2 Microwave Temperature Profiler dataset was collected by the Microwave Temperature Profiler (MTP), which is a passive microwave radiometer which measures the thermal emission from oxygen molecules in the atmosphere for a selection of elevation angles. Current observing frequencies are 56.6 and 58.8 GHz. Measured brightness temperature versus elevation angle is converted to air temperature versus altitude using a statistical retrieval procedure. An altitude temperature profile is produced every three km along the flight path. Data were collected from the Jacksonville Naval Air Station, Florida during the CAMEX-4 campaign spanning from August 26 - September 26. 2001.