Investigation of dynamic structure Hadley Cell circulation in belt tropics

Document Type : Original Article

Authors

1 Gruop, Climatologhy, znajan university, zanjan, Iran.

2 Climatology Group, zanjan university, zanjan. iran

10.30467/nivar.2021.237927.1164

Abstract

the European Mid-Term Prediction Analysis version (ERA5) data with horizontal spatial resolution of 0.25 * 0.25 degrees and using From air temperature maps, wind vector orbital component, zero level wind vector orbital component at 1000 hPa, wind vector meridian component, wind speed component, meridional performance current function, long wave output of ground output wave for 40 years (1979-1979) and was done using Gardes and MATLAB software. The results showed that the Hadley cell is confined to the lower margin of the subtropics and is due to the density difference resulting from the thermal gradient between the equator and the pole. Due to the rotation of the earth and the Coriolis deviation, heat transfer Low geography is observed in the tropics and its descent is about 30 degrees north and 35 degrees south, and the wind component orbital component winds rise from the west to the east near the earth's surface and from the east to the west at the high level. The meridional wind, the air that ascends, moves in a meridional direction towards the poles, then subsides and reverses in its direction and moves towards the equator, causing the formation of a Hadley rotation. To be. In the Northern Hemisphere, the desert regions of North Africa, the Middle East, Iran, and the southwestern United States are mostly in the Hadley cell dynamic branch, with a relative humidity of 22% Also in the southern hemisphere, the regions of Australia and South Africa with 32% relative humidity.

Keywords


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