Hydrology and Climate Change in Pacific and Similar Regions: Insights from Hawaii

Abstract

Population growth in Hawaii is causing major stress on available water resources. In addition, it is anticipated that climate change will lead to challenges concerning freshwater availability and negatively affect related natural habitats. This article reviews the consequences of changing rainfall, temperature, and solar radiation on groundwater resources. It also addresses the effect of sea level rise on the inundation of the coastal zone areas. Studies have shown that Hawaii is generally expected to face an overall decline in rainfall amount, increase in temperature, with a higher rate at elevated altitudes, and amplified rate of sea level rise. Such changes are projected to threaten groundwater availability and sustainability, cause recurrent hydrological droughts, and groundwater inundation and flooding of coastal zones. Nearshore problems can include damages to coastal infrastructures, salt‐water intrusion, and reduction in groundwater quality, and loss of aquatic habitats. Further, these impacts are anticipated to be amplified toward the end of this century. Owing to limited groundwater resource over the Islands, water use restrictions are most probably to happen with expected increases in agricultural water and other water‐use demands. Therefore, utilizing adaptation measures to climate change for Hawaii and similar Islands are of critical importance.