Climate Change: The importance of groundwater recharge by extreme rainfall
Richard Taylor in Tanzanian aquifer study
November 5th saw the publication on-line in Nature Climate Change of a study by Dr Richard Taylor (UCL Geography) and colleagues from the Tanzanian Ministry of Water and Irrigation, the University of Sussex and the British Geological Survey which suggests that intense rainfall associated with infrequent extreme events has beneficial effects on groundwater resources.
Such events are usually associated with negative socio-economic consequences such as crop and property loss. These findings, however, indicate that in future they could be increasingly beneficial, with groundwater becoming a vital water resource as climate change depletes other sources of supply.
This conclusion is based on study of a 55 year record of groundwater observations in a central Tanzania aquifer. It shows highly episodic recharge resulting from anomalously intense rainfall associated with major climate events in the region. It is predicted that the incidence of these events may increase, with model projections showing a future shift towards more intense monthly rainfall.
The research was supported by a grant from the British Government through the Department for International Development (DFID), Groundwater Resilience to Climate Change in Africa, and follows work published earlier this year in which the team for the first time quantified groundwater resources in Africa.