Little information is available on the temperature differences in the first several centimeters of air and water above and below the sea surface. A series of measurements was made to determine the magnitude and fluctuations of these temperature differences in the open Mediterranean Sea off the Ligurian Coast of Italy at about 44° 54.7'N, 9° 45'E. The differences were measured with respect to the actual undulating surface of the sea. The instrumentation used is described....