Unravelling the Drivers of the Recent Drought over Sao Paulo (Brazil) using HadCM3

Since ca. 2010, Sao Paulo has struggled with a multi-year drought. Reservoir levels of Sao Paulo, south-America's largest city, are at a record low level, and as a result the city has implemented water-controlling measures. Usually, the rainy season runs from October through March, bringing important rain for this city. However, over the last 5 years, Sao Paulo has experienced multiple years of below average rainfall. In this study, we try to explain the climatic drivers and mechanisms behind the observed drought over Sao Paulo using a combination of observations and model simulations. We analyse observed precipitation, air temperature and sea surface temperature (SST) datasets over the recent past to characterise the climate anomalies and visualize the extent of the drought. We then use the Hadley Centre Climate model (HadCM3) with prescribed observed SST anomalies to probe the possible causes behind the drought. This analysis will show us possible climatic drivers behind the drought in the most densely populated region of South America.