Hawai‘i and Pacific Islands [US Climate Reslience Toolkit]

The rate of increase in regional sea surface temperatures has exceeded global rates, while ocean acidification has reached levels not seen over the past 30 years. Sea level rise is compromising critical infrastructure and threatens to displace populations on low-lying atolls, forcing migration and disrupting social relationships. Climate change poses risks to the region’s rich biodiversity, including many threatened and endangered species, that supports functioning ecosystems and cultural practices. Access to clean, fresh water and healthy food is expected to be increasingly impaired by climate change. On low-lying atolls, sea level rise has caused saltwater contamination of fresh water. Degradation of coral reefs due to a rise in sea surface temperatures could incur coastal damages costing approximately $1.2 billion (in 2022 dollars) annually to the economies of Hawaiʻi and the US Pacific territories. Warming waters, acidification, and deoxygenation redistribute open-ocean fish stocks, and fisheries catch within regional EEZs is projected to decline by up to 40% by 2050 relative to the early 2000s under a very high scenario. U.S.-Affiliated Pacific Islands mangroves and seagrasses are among the world’s most productive blue carbon ecosystems, storing over 30% of total island carbon despite their small area. Adaptation efforts that build upon community strengths and center local and Indigenous Knowledge systems improve resilience.