Satellite observations of sea surface cooling by hurricanes

Sea surface cooling associated with 13 hurricanes in the western North Atlantic between September 1981 and December 1984 is examined using satellite-derived sea surface temperature fields. Some surface cooling is observed in all cases; however, because of cloud cover and the fairly weak signal in some cases, we see pronounced cooling along an extensive and continuous portion of the storm path for only three strong hurricanes. The persistence of cooling following the passage of a hurricane varies from a few days to at least 16 days. The amplitude of cooling is moderately well correlated with hurricane strength and is as large as 3.5°C. When the hurricanes move rapidly, the maximum cooling occurs well to the right of the track (approximately 70 km), whereas for slowly moving hurricanes the maximum cooling occurs near or on the track. Because western North Atlantic hurricanes are often found in close proximity to high pressure systems, daytime satellite images must be made with some care because of diurnal warming.