Horizontal eddy energy flux in the world oceans diagnosed from altimetry data
نویسندگان
چکیده
During the propagation of coherent mesoscale eddies, they directly or indirectly induce many effects and interactions at different scales, implying eddies are actually serving as a kind of energy carrier or energy source for these eddy-related dynamic processes. To quantify this dynamically significant energy flow, the multi-year averaged horizontal eddy energy fluxes (EEFs) were estimated by using satellite altimetry data and a two-layer model based on hydrographic climatology. There is a strong net westward transport of eddy energy estimated at the mean value of ~13.3 GW north of 5°N and ~14.6 GW at the band 5°S ~ 44°S in the Southern Hemisphere. However, poleward of 44°S east-propagating eddies carry their energy eastward with an averaged net flux of ~3.2 GW. If confirmed, it would signify that geostrophic eddies not only contain the most of oceanic kinetic energy (KE), but also carry and spread a significant amount of energy with them.
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