Hawaii is one of the smallest states in the US with a population of 1.4 million. With a total land area of almost 11,000 square miles, it is close to the size of Massachusetts. The Hawaiian Islands have only two seasons: summer (kau) from May to October and winter (hooilo) from November to April. Each island has its own unique environment, making Hawaii home to all kinds of biomes, including tropical rainforests, cool alpine regions, and arid deserts.
Climate change has strong adverse effects on Hawaii’s ecosystems and economy. Ocean warming and acidification are decimating the islands’ marine ecosystems, especially coral reefs, which are hugely important because they provide a safe place for fish to spawn, protect Hawaii’s coasts from waves and storms, and support tourism and fishing industries worth billions of dollars. Coral reefs are also fundamental to the fabric of local communities in Hawaii, providing a source of food, materials, and traditional activities.
A related and useful non-climate change fact: research shows that common ingredients in sunscreen such as oxybenzone and octinoxate severely threaten ocean ecosystems. In Hawaii, due to its strong tourism industry, coral reefs are exposed to over 6,000 tons of sunscreen lotion every year. For context, a 2015 study showed that oxybenzone starts causing serious damage to corals at concentrations as low as the equivalent of one drop of water in six-and-a-half Olympic-sized swimming pools. In Hawaii, popular swimming spots see concentrations more than 10 times that amount. Find reef-safe sunscreens here.
Increasing heat levels also threaten Hawaii’s land flora and fauna, most of which are found nowhere else on earth. High temperatures are also a danger to Hawaii’s residents, as heat-related deaths rise in the wake of global warming. Since 1950, temperatures in Hawaii have risen 2 degrees (F).
Hawaii is also seeing increasingly intense rainfall events. On April 15th, 2018, 50 inches of rain fell on Hanalei in just 24 hours. That kind of rain is devastating to its ecosystems and population — and it’s a direct result of climate change. While extreme precipitation events become more common in some areas, overall annual rainfall has decreased in Hawaii since the 1980s.
Because Hawaii is an island chain in the middle of the ocean, sea level rise harms the state drastically, and has even eliminated entire islands. Whale Skate Island, a small island formerly located in Hawaii’s northwest region, disappeared due to sea level rise along with several other islands. In general, the Northwestern Hawaiian Islands, which are low-lying and therefore at great risk from increasing sea levels, also have a high concentration of endangered and threatened species. Sea levels are projected to continue to rise three feet along the coast of Oahu during the rest of this century due to global warming.
In August 2023, the island of Maui experienced devastating wildfires, the deadliest in the U.S. in over a century. A series of factors contributed to the unprecedented wildfires, including rising temperatures, severe drought, and the spread of invasive grasses. According to the Hawaii Climate Change Mitigation and Adaptation Commission, the wildfires were a moment when Hawaii experienced “the severity of the [climate] crisis.”
In 2023, Biden approved $95 million in federal funds for Hawaii Electric, which provides power to 95% of Hawaii’s residents. The funds followed devastation from windstorms and wildfires, and will help pay for the Climate Adaptation Transmission and Distribution Resilience Program, a proposed five-year climate resilience plan.
Hawaii has no natural gas fired generation, nuclear power plants, or coal-fired power plants. The last coal fired power plant retired in 2022, making 2023 the first year since 1980 where Hawaii had no utility-scale, coal-fired generation. Its islands are further from a major land mass than any other island chain on earth forcing the state to rely on energy that’s easy to ship in — mainly petroleum. Hawaii is a special case when it comes to energy consumption. Because of its generally mild climate, Hawaii ranks among the 5 states with the lowest total energy use. The transportation sector accounts for more than half of all energy consumed in Hawaii and for two-thirds of petroleum consumed. In 2023, petroleum accounted for 67% of the state’s total electricity generation.
The only energy generated in Hawaii itself is renewable, with renewables now accounting for 31% of total electricity generation. Solar was the majority of this (60% of renewable), mostly from small-scale solar panel generation. With 1230 megawatts of total solar power generating capacity, Hawaii had the 11th highest small-scale solar generation of any state in 2023.
Hawaii has eight utility-scale wind farms, and wind energy accounted for 29% of renewables (6% total electricity) in 2023. Hawaii has one geothermal power plant, located on the Kilauea Volcano, making it one of seven states with utility-scale geothermal energy generation. In 2023, geothermal was 10% of renewables (3% total). The rest of renewable energy came from biomass (9%) and hydropower (3%).
Nearly all of Hawaii’s utility-scale battery storage capacity is installed with onshore wind turbines or solar photovoltaic (PV) systems, allowing excess electricity from those generators to be stored and used later. By storing excess output from wind and solar power plants, batteries can provide electricity during times of low wind and solar output and reduce the need for other forms of generation. In 2024 two new facilities began operations: The Kūihelani Solar-plus-Storage facility, Hawaii’s largest, and the Kapolei Battery Energy Storage Facility.
Hawaii is one of twenty five states committed to the U.S. Climate Alliance, which is working to implement policies that advance the goals of the Paris Agreement. In 2015, Hawaii set a goal for 100% of its electricity to come from renewable sources by 2045, making it the first state to set a legally required deadline. It also created an Energy Office and new electric vehicle programs. Hawaii adopted California’s appliance efficiency standards, plus climate taxes on fossil fuels, and programs to encourage green industry. Its Climate Commission created three working groups centering around equity, transportation, and legislation to properly serve Hawaii’s community. To help reduce its reliance on petroleum, they implemented the Hawaii Clean Energy Initiative to displace 70% of petroleum-based ground transportation fuels with non-fossil fuels by 2030.
In 2014, Hawaii passed House Bill 1714 establishing the interagency Climate Adaptation Committee, later renamed the Hawaii Climate Change Mitigation and Adaptation Commission, which was charged with developing vulnerability and adaptation reports on the effects of sea-level rise and leading the state’s efforts to reduce greenhouse gas emissions in line with the goals set out in the Paris Agreement. The Commission was also charged with identifying climate vulnerabilities across all sectors in Hawaii, assessing existing efforts and capacities of existing resources to address goals, setting goals and creating strategies for both mitigation and adaptation, and tracking and reporting on implementation progress.
In December 2017 the Commission released the mandated Hawaii Sea Level Rise Vulnerability and Adaptation Report, providing statewide and island specific recommendations to increase coastal resilience and decrease vulnerability to sea level rise. Building off the report, Hawaii Department of Land and Natural Resources, the Office of Planning, and the University of Hawaii Sea Grant College Program developed three tools: the Hawaii Sea-Level Rise Viewer, Integrating Coastal Hazards and Sea Level Rise Resilience in Community Planning, and Guidance for Disaster Recovery Preparedness in Hawaii.
Established in 2007, Hawaii’s Greenhouse Gas Program regulates GHG emissions statewide and releases annual inventory reports. The latest reports and projections reveal the state is not on track to meet its greenhouse gas emissions goals, according to the Hawaii Climate Change report for 2023. The Greenhouse Gas Sequestration Task Force was established in 2018 by Act 15. Its 19 members are also required to be members of the Climate Change Mitigation and Adaptation Commission. The Task Force is entrusted to establish a baseline for greenhouse gas emissions and benchmarks for greenhouse gas sequestration, as well as identifying policies for agricultural and aquacultural practices, land use, composting, and reforestation that would promote increased greenhouse gas sequestration.
In July 2021, the state passed Act 178 and 179, two laws increasing sea-level resilience in Hawaii. Also in July 2021, Hawaii became the first U.S. state to declare a climate emergency with S.C.R. 44, also releasing a statement on investing federal funding on climate change. In June 2022, Act 185 established a carbon-smart land management assistance pilot program in Hawaii. The program will compensate small farmers, foresters and landowners for best climate practices, including reforestation, windbreaks, crop diversity, crop rotation, and composting.
An especially creative and innovative resource is Koloa Iki, an educational website highlighting sea level rise, named for the Hawaiian duck Koloa Maoli. Developed by the artists Solomon Enos in partnership with the Climate Change Mitigation and Adaptation Commission, the interactive website includes art, challenges, sing alongs, games, and characters like Sea Wall Girl to help educate the public, especially children, about sea level rise in an accessible and fun way.
As part of the U.S. Climate Alliance, the Commission has outlined Hawaii’s commitments in over 70 priority areas. These HI Impact Actions include measurable targets: 100% net-zero emissions government buildings by 2030; 100% ZEV new light-duty sales by 2035, 100% zero-emission public fleets by 2035 and transit bus flights by 2030; conserve at least 30% of land and coastal waters by 2030; increase tree canopy by 40% by 2030 to mitigate urban heat island effects; and increase consumption of food produced within the jurisdiction to at least 20-30% by 2030. They also include broader goals like promoting sustainable communities, integrating racial and gender diversity in developing environmental solutions, commiting to large scale restoration of forests and other locally Indigenous ecosystems, and considering utilizing the social cost of GHG emissions across relevant policy-making and decision-making processes.
The Commission’s latest Annual Report (2023) outlines their latest efforts, including the first Community Climate Fairs, a $3 million grant from the EPA for climate mitigation planning, renewing AmeriCorps VISTA funding for the Climate Ready VISTA Cohort, a pilot project to address the impacts of sea level rise and coastal erosion at Punalu’u Beach Park, and a working group on environmental justice to address the issue that Biden’s Justice40 Initiative does not accurately identify eligibility in Hawaii.
In March 2024 the Hawaii Climate Change Mitigation and Adaptation Commission released Hawaii’s first Priority Climate Action Plan. The plan was developed to apply for over $4.6 billion in EPA funding, and outlines 17 priority actions across islands to reduce future climate impacts, focusing on reducing GHG emissions. In the summer of 2025 the state is due to release a Climate Action Pathway, a more comprehensive, community-focused action plan, with a status report due in 2027.
