Hawai‘i Climate Impacts and Costs

The report details how Hawaii is experiencing accelerating climate crises, specifically through extreme drought, intense tropical storms, sea level rise, and increasing temperatures. It provides comprehensive lists of potential costs for mitigation and adaptation, ranging from water management and wildfire suppression to floodproofing infrastructure and public health interventions.

• Hawaii has recently faced extreme drought conditions, with the period from 2010-2019 marking the lowest rainfall for any consecutive 10-year period since 1900. This trend is evidenced by a decline in rainfall and streamflow since the 1990s and a visible "browning" of the islands over the last four decades.
• Climate-driven drought has increased wildfire risks, with the area burned by wildfires in Hawaii increasing fourfold to an average of 8,427 ha/yr. A notable example is the Maui wildfires, which destroyed Lahaina and caused at least 97 deaths.
• Water security is threatened by decreasing availability in several watersheds. The Nuuanu watershed on Oahu is projected to see a decrease of up to 27%, and the Na Wai Eha watershed is seeing rainfall declines that threaten the groundwater source for 80% of Hawaii's drinking water. This occurs while water demand may increase by up to 36% by the end of the century.
• Tropical storms and hurricanes are becoming more intense, leading to significant infrastructure damage and flooding. In April 2018, Kauai received 50 inches of rain in 24 hours, flooding over 500 homes and causing $20 million in public property damage.
• Sea levels in Hawaii have risen an average of 10 inches compared to 1950, leading to increased coastal inundation. In Honolulu, the average number of high tide flooding days per year has nearly doubled from 6 to 11 since the 1960s. Additionally, approximately 92% of shorelines are predicted to retreat by 1-24 meters by 2050.
• Rising temperatures threaten both public health and the economy. The average annual temperature in 2016 was approximately 1.7°F warmer than the 100-year mean. Warmer ocean temperatures threaten coral reefs, which are estimated to generate 60% of Hawaii's tourism income.

APA

Center for Climate Integrity (2024). Hawai‘i Climate Impacts and Costs. https://climateintegrity.org/uploads/media/CCI-Hawaii-ImpactsAndCosts-2024.pdf

Chicago

Center for Climate Integrity. Hawai‘i Climate Impacts and Costs. 2024. https://climateintegrity.org/uploads/media/CCI-Hawaii-ImpactsAndCosts-2024.pdf.

Wikipedia

{{cite report |author=Center for Climate Integrity |title=Hawai‘i Climate Impacts and Costs |date=2024 |url=https://climateintegrity.org/uploads/media/CCI-Hawaii-ImpactsAndCosts-2024.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{centerforclimateintegrity2024hawaii, author = {{Center for Climate Integrity}}, title = {{Hawai‘i Climate Impacts and Costs}}, institution = {Center for Climate Integrity}, year = {2024}, url = {https://climateintegrity.org/uploads/media/CCI-Hawaii-ImpactsAndCosts-2024.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }