El Niño · Pacific Walker Circulation — 3D view

Domain: 40°E–70°W, 45°S–45°N. During an El Niño event, the Tropospheric Temperature Gradient (TTG) over the Indian Ocean reduces. Observe the red upper-troposphere box over India becoming less intense and rainfall decreasing as the El Niño warming phase strengthens in the Pacific.

40°E–70°W · 45°S–45°N
Switch between Normal and El Niño
Upper troposphere box (~200 hPa) — warm core
Lower troposphere box (~850 hPa) — boundary layer
TTG over India reduces as Pacific trade winds weaken.
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