Space-time variability of the field of mechanical energy transfer from the atmosphere to the Indian Ocean

Abstract

An analysis of the spatial and temporal variability of the field of mechanical energy transfer (MET) from the atmosphere into the ocean is based on a separate numerical simulation of evolution for the terms of source function for a wind-wave model conducted in the Indian Ocean area for the period 1998 to 2009. The MET field is described by two integral values calculated per unit area: the total rate of energy flux from the wind to waves, IE(x, t), and the rate of energy-loss flux for the wind waves, DE(x, t). To solve this problem, the wind field W(x, t) is used, downloaded from the NCEP/NOAA archive [1], and the fields IE(x, t) and DE(x, t) were calculated using the numerical model WAM [2] with the modified source function proposed in [3]. Maps for the fields IE(x, t) and DE(x, t) were obtained by calculations with different scales of the space-time averaging, extreme and average values of the MET were found, seasonal and interannual variability was estimated, and the 12-year trend for several mean quantities was obtained.