Extended Abstract (108K)10B.4
Spatial-time structure of the energy content over tropics
Valery N. Khokhlov, Odessa State Ecological University, Odessa, Ukraine; and A. V. Glushkov
Using GDAAC data the energy content over tropics is investigated. The contents of zonal mean kinetic (KM) and eddy available potential (PE) energies are enlarging towards the latitudinal boundary of tropical zone whereas eddy kinetic (KE) energy content has maximum (0.97·106 Jm-2) over equator. Such KM distribution is assigned to the maximal values in the 200-100 hPa layer (23.7·105 Jm-2 at southern boundary and 12.5·105 Jm-2 at northern one). In the vertical structure of the PE content there are two maximums in atmospheric boundary and 300-200 hPa layers for each hemisphere. In the Southern Hemisphere these maximums are 2.9·105 Jm-2 for ABL and 1.2·105 Jm-2 for top troposphere; for Northern Hemisphere they are 4.3·105 Jm-2 and 3.4·105 Jm-2 respectively. The KE vertical structure has also two maximums over equator, first in the 800-700 hPa layer (1.3·105 Jm-2) and second in the 200-100 hPa layer (3.1·105 Jm-2). Maximal content of KM is registered in June (15.5·106 Jm-2) at southern boundary and in February (17.8·106 Jm-2) at northern one. Reverse pattern is observed for PE spatial-time distribution. Here maximal values of PE content are 1.4·106 Jm-2 in January at southern boundaries and 5.4·106 Jm-2 in June at northern one. Highest values of KE content are located on equator in January (1.8·106 Jm-2) and approximately on 15N in June (2.4·106 Jm-2).
The carried out analysis has shown that the energy conversion in the tropics has seasonal variability. In summer the most intensive processes are realised in Southern Hemisphere and in winter - in Northern Hemisphere. The available potential energy converts to the zonal mean kinetic energy and this conversion looks as decreasing of PE and increasing of KM in corresponding season. At that the intensity of Hadley cell plays the large part in this process especially in northern part of tropics. The greater heterogeneity of the terrestrial surface along latitudinal belt in Northern Hemisphere plays also the large part that consists in the conversion of eddy available potential energy into eddy kinetic one.
Session 10B, Large-Scale Dynamics and Convection V (Parallel with Sessions 10A, 10C, and 10D)
Wednesday, 1 May 2002, 2:00 PM-3:30 PM
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