SEASONAL VARIATION OF ANGULAR MOMENTUM TRANSPORT AT 500 MB.

Abstract

Monthly mean values of the geostrophic angular momentum transport at 500 mb. have been computed as a function of latitude and zonal wave number (1 through 10) for a 10-yr. period. The total transport is found to be in good agreement with previous calculations; at the same time several wave numbers exhibit considerable individuality. Equatorward transport by wave 2 at high latitudes extends farther south, and is much larger in magnitude, than the transport by any of the other wave numbers. Also, the negative transport in low latitudes is in distinct contrast to the behavior of the other waves. Wave 3, on the other hand, transports momentum poleward in mid-latitudes at a rate at least twice as great as that of any other wave number. An additional finding is that in July and August, waves 1 through 5 are relatively inactive in transporting momentum, while waves 6 through 10 accomplish substantial transport near the latitude of the summertime maximum westerlies.