Storylines of Maritime Continent dry season precipitation changes under global warming

Abstract

<p>The dry half of the year from May to October over the Maritime continent is a crucial period. Because a severely dry year could lead to unprecedented damages due to forest fires. The amount of rainfall during this period is closely tied to the sea surface temperature (SST) evolution over the tropical Pacific Ocean. The future change in the tropical Pacific SST has uncertainty with majority of the climate models showing a higher warming over eastern tropical Pacific. However multiple climate models show a higher warming rate over the western tropical Pacific, known as the warm pool region. This feature can also be seen in observations over the last 120 years. The effect of this differing tropical Pacific SST evolution can have contrasting influence over the maritime continent precipitation. Therefore, this study provides a risk-based estimate of the future dry season maritime continent precipitation, which is based on the possible evolution of tropical Pacific SST through physical climate storyline approach. We provide storylines of future dry period precipitation using the outputs of 38 climate models from Coupled Model Intercomparison Project version 6 (CMIP6). Our results suggest that a higher basin wide tropical Pacific warming with higher warming in the eastern tropical Pacific than the west would lead to a drier condition over the Islands of Sumatra and Java. Whereas lower increase in basin wide tropical Pacific SST with a warmer western tropical Pacific, which we saw in observations, would lead to wetter condition over the Islands of Borneo and Neu Guinea.</p><p> </p>