Relationship of convective precipitation with atmospheric heat flux — A regression approach over an Indian tropical location

• Atmospheric heat flux and sea surface temperature controls convective precipitation.
• Increased convective cloud and surface evaporation enhances convective precipitation.
• Another factor for increase in convective precipitation is moisture flux divergence.
• CPE index is proposed to estimate the convective precipitation over tropical region.
• Good agreement between the model results and MERRA observations are obtained.

The response of atmospheric heat fluxes and sea surface temperatures on the convective precipitation over the tropics has been an important area of research in recent decades. A long-term observation (1979–2008) of the increase in convective precipitation in relation to the latent and sensible heat fluxes on a tropical location, Kolkata, has been investigated in the present study. Invigoration of convective precipitation has been caused by vertically integrated divergence of moisture flux, rise in sea surface temperatures, convective cloud cover and surface evaporation rate over the tropical region. A convective precipitation estimation (CPE) index is proposed, considering the Bowen ratio, surface evaporation rate, sea surface temperature and temperatures at 500 hpa pressure level during the pre-monsoon season (March–May), to estimate the amount of convective precipitation over the tropics using multiple linear regression technique is also another aim of this study. A good agreement is obtained between the results from the proposed model and the MERRA observations during the years 2009–2013.