Groundwater replenishment in Sub-Saharan Africa: evidence from multi-decadal observations - W.M. Edmunds Memorial Lecture.

In a career spanning almost 50 years, Professor W. Mike Edmunds made an extraordinary contribution to water science and water resource management globally. Mike led advances in geochemistry – particularly hydrogeochemistry and palaeohydrology – authored over 150 scientific publications and mentored numerous water professionals in the process. In recognition of his outstanding work, Mike received many accolades including the Whittaker Medal (1999), the O.E. Meinzer Award (2009), and the Vernadsky Medal (2010). Mike is remembered not only for his scientific achievements, but for his passion, warmth and generosity of spirit which touched the lives of many. This lecture aims to honour his legacy by promoting good hydrogeological science to the service of society: something Mike was deeply passionate about.

Groundwater replenishment in Sub-Saharan Africa: evidence from multi-decadal observations
Dependence on groundwater withdrawals to alleviate poverty is growing across Sub-Saharan Africa, where groundwater is often the only perennial source of freshwater. Despite substantial uncertainty that persists in projections of climate change, the 5th Assessment Report of the Inter-governmental Panel on Climate Change concluded with high confidence that large reductions in groundwater recharge are expected in drylands globally. However, the processes by which groundwater is replenished in the tropics remain inadequately resolved; model output is untested and uncertain.

The 2018 Edmunds Lecture will review new evidence of recharge process and relationships between rainfall and recharge from recently collated, multi-decadal records of groundwater levels in 9 countries across tropical Africa. A key focus of this review is how groundwater recharge may be influenced by the amplification of extreme rainfall, an impact of global warming that is physically based and well-observed.

About the speaker
Richard Taylor is a Professor of Hydrogeology at the University College London (UCL). His area of expertise lies in the use of groundwater resources to improve access to freshwater for agricultural and domestic purposes in low-income countries across the tropics. His research draws not only from the physical sciences including hydrogeology, hydroclimatology, chemistry, remote-sensing and numerical modelling but also from social sciences including political economy, hydropolitics, and metrics (e.g. human ecology).