ADDRESSING WATER RESOURCE ISSUES IN BARBADOS FROM AN ISOTOPIC, MESOSCALE, AND SYNOPTIC CHARACTERIZATION OF PRECIPITATION VARIABILITY

Extreme events, such as flooding and drought, caused by climate change will alter how humans utilize water resources in the future. Tropical island nations, such as Barbados, are particularly vulnerable as changes in storm frequency and intensity will influence karst aquifer storage. Here, we present a study using an isotopic hydroclimatological analysis of Barbados’ rainfall and groundwater in relation to mesoscale and synoptic characteristics of individual storm events to better understand the evolution of storm events and their relationship to groundwater resources. Over a period of 1.5-years, weekly samples of dripwater, rainfall, groundwater, and 10-minute precipitation amounts were collected from Harrison’s Cave. These samples underwent isotopic analysis for oxygen and hydrogen isotopes. TRMM satellite data was used to characterize isotopic variability with synoptic and mesoscale storm features. Since July 2012, the data indicates the amount effect dominates the precipitation isotope signal in groundwater and dripwater, and that seasonal variations in rainfall may play a large role in water resource variability, which are impacted from teleconnection influences in the Caribbean region. These results help with our understanding of the nature and causes of rainfall variability in the Caribbean, and our interpretation of paleoclimate proxies, such as stalagmites from caves, in an attempt to better manage water resources in the face of future climate change.