On the Importance of Precipitation‐Induced Surface Sensible Heat Flux for Diurnal Cycle of Precipitation in the Maritime Continent

The Maritime Continent (MC) exhibits a pronounced diurnal cycle in precipitation, with many high‐resolution models overestimating the diurnal peak and predicting earlier precipitation over the islands than observed. We hypothesize that part of this model bias comes from ignoring precipitation‐induced surface sensible heat flux (QP). To test this conjecture, we performed simulations with and without QP for April 2009 and June 2006. The inclusion of QP reduced the bias in diurnal peak precipitation amplitude by 83% in April 2009 and 23% in June 2006. Similarly, the bias in precipitation peak timing decreased by 26% and 15%, respectively. This bias reduction was even more prominent during periods of heavier rainfall. This improvement in both the amplitude and phase of diurnal precipitation also led to a reduction in bias for total precipitation by ∼10%. These findings suggest that QP cannot be neglected over the MC, particularly during heavy precipitation. Plain Language Summary The surface energy budget is an important factor that influences precipitation. One of the components of the surface energy budget is the sensible heat flux due to precipitation (QP), which occurs because the temperature of raindrops is typically cooler than the surface temperature. QP is often considered small and is usually neglected in climate models. However, QP may not be negligible over areas with heavy rainfall, such as the Maritime Continent (MC), the largest archipelago in the world. Our study incorporates QP into a regional climate model to assess its effects on precipitation and its diurnal cycle in the MC. We found that QP reduces the bias in the amplitude and phase of diurnal peak precipitation. The improved diurnal cycle in precipitation further reduces the bias in total precipitation. The results indicate that QP may not be neglected over the MC. Key Points Models struggle to capture precipitation and its diurnal cycle over the islands in the Maritime Continent (MC) Incorporating precipitation‐induced surface sensible heat flux improves the simulated diurnal cycle in precipitation over the islands Improved diurnal cycle in precipitation can improve longer‐term simulation of precipitation in the MC