Variations of Hydrographic Properties and Heat Budget Observed at 0°, 156°E during the TOGA COARE R/V Natsushima Cruise

Continuous CTD casts and meteorological observations were made from a station at 0°, 156°E from February 5 to February 14, 1993 during the TOGA-COARE Intensive Observation Period. Large temperature variations were found around 240, 340, 570 and 760 dbar. These variations affect the surface geopotential anomaly (dynamic height) with a standard deviation of ±0.28 m 2 /s 2 at the sea surface. In the ocean surface layer (0-60 dbar), the 10 day average heat storage rate (the rate of change of heat content) was -27.1 Watt/m 2 (positive means cooling), and the similarly averaged surface heat flux calculated from the meteorological data on the ship was -24.2 Watt/m 2 (positive means upward with heat loss of the ocean). This balance suggests that the mixed layer temperature was mainly controlled by the local surface heat flux during the 10 days of our observation period, although the residual (defined as heat storage rate minus surface heat flux) was large in the calculation for each 6 hours.