Daily spectral energy conversions of the global circulation during 10-27 Jan. 1979

• Published in: Tellus. Series A, Dynamic meteorology and oceanography Vol. 40; no. 1; pp. 37 - 49
• Main Authors: Huang, Huo-Jin, Vincent, Dayton G
• Format: Journal Article
• Language: English
• Published: 01.01.1988
• ISSN: 0280-6495

The energetics of the daily wave activity over tropical and middle latitudes are examined for part of the first special observing period of FGGE by using a modified version of ECMWF Level 3-b analyses. Overall, the results agree well with prior investigations. It is found that the eddy available potential (AE) is increased by sensible heat transport down the temperature gradient (CA) at all wavenumbers and that it is immediately converted to eddy kinetic energy (KE) through warmer air rising and /or colder air sinking (CE). Moreover, it is seen that this energy cycle takes place at each individual wavenumber n, with the major contributions being due to n = 2-4 and n = 6-7. It is also seen that the wave-to-wave interactions are generally much less important than the remaining terms in the eddy energy budgets. Special attention in this study is devoted to the Southern Hemisphere energetics. In the southern Tropics, it is found that CE dominates over other conversion processes. The contribution from n = 4 accounts for the major portion of this conversion. It appears that latent heating in the South Pacific may be the main cause for the significance of this wavenumber-4 domination. In southern midlatitudes, all conversion terms are equally important, and the major contributions occur at intermediate wavelengths, n = 6-8. The energy cycle consists of a conversion of zonal available potential energy (AZ) to AE to KE to zonal kinetic energy (KZ).