Freshwater resources are essential to life on Pacific Islands. Water is needed for human consumption, as well as for agriculture, industry, ecosystems and public health. Each island location relies on a different mix of freshwater sources, including groundwater, surface water, and rainwater catchment, but the small size of islands means that these resources are limited. Climate change may pose serious challenges for island freshwater resources.
The Pacific Islands face a range of challenges from sea-level rise. Higher average water levels and increasingly frequent extreme water-level events threaten infrastructure, property, groundwater, waste water systems, sandy beaches, and coral reef ecosystems. Atolls and low islands are especially vulnerable, and it may become difficult to for populations live in low-lying areas.
The Pacific Islands are host to diverse and fragile terrestrial (meaning “land-based”) ecosystems that provide people of the region with food, income, recreation, shared cultural heritage, and many other benefits. Terrestrial ecosystems take diverse forms and are distinct between high islands and low islands. The wide range of ecosystem types on Pacific Islands include, for example, the high-elevation native cloud forests and bogs found on some high islands and the coastal strand ecosystems of many low islands and coastal areas of high islands. These ecosystems and their services are at risk from climate change and local stress from human activities.
The Pacific Islands region contains some of the most diverse ocean and coastal ecosystems in the U.S. These ecosystems contain species and communities of species of value economically, culturally, and for conservation, protection, and global biodiversity. These species include, among others, pelagic fish (such as tuna), reef fish, corals, endangered sea turtles and monk seals, marine mammals, and plankton, which form the base of the food web. Climate variability and change threaten marine and coastal ecosystems through rising air and sea-surface temperatures, sea-level rise, changes in seasons, changes in the frequency and intensity of extreme weather events (such as tropical cyclones and heavy rain events), changes in solar radiation, and increasing ocean acidification.
Climate change confronts Pacific Islands and their communities with enormous challenges that may affect every aspect of life. The close proximity of populations and structures to the ocean contributes to island communities’ vulnerability to climate change. Island economies generally depend on local ecosystems and limited sources of revenue, so any external stresses from climate impacts hit particularly hard. Human health will be increasingly impacted by climate change through extreme events, heat-related illnesses, psychological stresses, and a possible increase in infectious disease. These climate impacts, on top of other socioeconomic and political motivations, may lead individuals or even entire communities to consider migrating to a new location.