Unravelling the mechanisms behind Multi-Year Droughts

Recent decades have seen a doubling in multi-year droughts around the world.

With long-lasting impact on streamflow, groundwater and vegetation, these negatively affect agriculture, drinking water supply, hydropower, shipping and ecosystems as a result.

The IPCC states that contrary to normal droughts, multi-year droughts cause abrupt changes that take years or decades to be reversed.

Due to climate change, multi-year droughts are projected to become more frequent and longer, and potential recovery times between droughts will decrease.I hypothesise that the rise in multi-year droughts and their impacts is caused by stronger teleconnections between the atmosphere, ocean and land, enhanced by climate change, and that feedbacks between the bio-hydrological cycle exuberate the impacts of multi-year droughts.

The MultiDry project will make scientific breakthroughs by tracking the propagation of multi-year droughts from climate forcing, through vegetation and soil moisture to surface water and groundwater impacts, whilst also including the important, intricate affects of human water use.

In MultiDry, I will combine observations with a novel modelling framework to unravel the drivers behind multi-year droughts worldwide, and the feedbacks of vegetation and human water use on drought duration, propagation, and recovery.

This will yield new process understanding, novel scientific datasets, and a basis for reliable projections of future multi-year drought events.This project will drastically improve our understanding of the drivers and mechanisms of multi-year droughts that I believe to be fundamentally different from those of normal droughts.

The MultiDry results will inform policymakers and water managers around the world on future water challenges.

MultiDry will also provide the fundamental understanding needed to quantify future drought vulnerability around the world, help to improve drought preparedness and improve global hydrological modelling of drought.