Hydrologic balance of the Gulf of Mexico

Abstract

The hydrologic cycle of the Gulf of Mexico is considered for the year 1 October 1958 to 30 September 1959. Both branches of the water cycle, atmospheric and surface, are treated separately on a monthly, seasonal and annual basis. Results of each treatment are combined to determine a consistent description of the water balance for the basin during the period. Determinations of the separate components of the atmospheric branch were based on the continuity equation for water vapor. Values of horizontal water-vapor divergence and storage-water change were obtained for the volume of air overlying the Gulf. Computations were based on standard aerological data for ten stations around the perimeter of the Gulf. From these computed values the net vertical exchange of water between sea and air was obtained. An electronic computer, IBM-704, available on the campus was used for performing most of the calculations required. Evaluation of the surface water branch rested on continuity considerations of the water mass. Monthly values of river discharge into the Gulf were determined from standard measurements. Combination of discharge data and computed values of the net vertical exchange between sea and atmosphere yielded the net flow through the straits of Florida and Yucatan. An analysis of results is presented. Emphasis is placed on an evaluation of atmospheric water-vapor transports. Significant differences which occurred between the west and east sectors of the Gulf are described. Contributions to the water balance resulting from eddy fluctuations of wind and moisture are stressed. Associated variations in the difference between evaporation and precipitation are considered from the standpoint of their effects on the salt, as well as water, balance of the Gulf..