Projected Future Precipitation Scenarios for a Small Island State: The Case of Mauritius

Abstract

The economies of small island developing states (SIDS) can be sensitive to climate variability in the future. In this chapter, we use four of IPCC’s Fourth Assessment Global Circulation Models (GCMs) to produce precipitation projections for the next 90 years for the small island state of Mauritius. We focus our projections on the Vacoas-Phoenix region of this island because (a) this is the central region of the island, where all the major water reservoirs are located, (b) this region has normally higher precipitation and a higher variability of precipitation than the coastal regions, and (c) the rainfall in the mountainous part of this region feeds most of the rivers. Thus we expect that the groundwater recharge rate is probably more sensitive to precipitation in this region. Our results show that historically wetter months are likely to become wetter while drier months could become even drier than currently observed, but the net annual precipitation is likely to decline. This can have a significant impact on the growing tourist industry in the region which is likely to strain its water resources.