Future drought changes in Australia from multiple projections

Abstract

Australia suffers from frequent droughts but future drought changes have remained stubbornly uncertain over the continent, with CMIP projections indicating low model agreement across most regions. Here we constrain future changes in drought over Australia by combining a hierarchy of projections from coupled global and regional climate models and several offline hydrological models that are widely employed in Australia. We analyse changes across multiple types of droughts (meteorological, hydrological and agricultural) to understand robustness of trends across drought types. Using this multi-projections approach, we identify robust future increases in drought across key agricultural and densely populated regions that are consistent across different drought types. Our study demonstrates value in analysing multiple projections together to build confidence in future changes in other regions of the world where model uncertainty is high.