The 1995 UK drought - A signal of climatic instability?

Drought conditions in the Uh produced considerable water supply stress during 1995 and attracted substantial public, political and scientific interest. In this paper the drought's extent and severity throughout the spring and summer period is examined from a water resources perspective, within the context of the unusual climatic conditions which have characterized much of the last 20 years. The last two decades have seen both an exaggeration in the north-west to south-east rainfall gradient across Britain and a more distinct partitioning of annual rainfall totals between the winter and summer half-years. In addition, most of the recent past has been remarkably mild, encouraging exceptionally high rates of evaporation. These tendencies, which show a broad consistency with a number of favoured climate change scenarios, have raised questions regarding the resilience of existing water resource management strategies. In the context of historical rainfall and temperature records, the level of risk adopted by the water industry is shown to be of the right order. However, recent patterns of rainfall, evaporative losses and peak water demands suggest the type of water supply stress experienced during 1995 may now be occurring with a greater frequency. The recent clustering of hot, dry summers-together with the associated surge in water demand-implies that the water industry should direct more attention to contingency planning based on substantially lower return periods than those reported for drought events over the last 20 years.