Abstract This study examines the evolution of “top‐heaviness” in tropical convection during extreme precipitation events. Top‐heaviness describes the extent to which ascent peaks in the upper (top‐heavy) versus lower (bottom‐heavy) troposphere. Reanalysis vertical velocity profiles are projected onto two sinusoidal basis functions, representing the first and second baroclinic modes, that together characterize top‐heaviness. Two distinct modes are found following the peak in rainfall: stratiform decay and convective decay. Stratiform‐decay events transition rapidly from bottom‐heavy to top‐heavy to stratiform‐like ascent profiles and experience sharp reductions in instability, moisture and precipitation after the peak of the event. In contrast, convective‐decay events sustain bottom‐heavy ascent profiles with a gradual decline in instability and moisture and prolonged precipitation; they contribute over 55% of the rainfall during extreme events. These findings emphasize the significant role of convective decay in shaping extreme precipitation compared to conventional stratiform decay.
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Last updated: November 30, 2025 04:25 AM
Atmospheric CO₂
426.8 ppm
+18.1
ppm/year
Atmospheric CH₄
1927.61 ppb
+2.73
ppb/year
Global Temperature
+1.48 °C
Peak: +1.73°C
World Population
8.1 billion
+67
million/year