The Cost of Climate Change for the Future of Hawaii

Climate change is threatening to dramatically change life in Hawaii. The tourism industry might all but vanish. Oceans, ecosystems, rainfall and the immunity of the state’s inhabitants will all come under threat.

The Cost of Climate Change for the Future of Hawaii

Hawaii is one of the most beautiful vacation spots in the US, attracting tourists from all around the world. Its beautiful scenery, near-perfect weather all year round, and fantastic food mean that tourism accounts for 21% of the state’s economy. In 2017, 9.4 million people visited the island, bringing in a total of $16bn.

Unfortunately, climate change is threatening to severely change things around the state over the coming decades. The tourism industry might all but vanish.

According to a report by the University of Hawaii, commissioned by the Hawaii Tourism Authority (HTA), the state might look very different in the coming decades as climate change will make it hotter and stormy. There will also be a rise in diseases as oceans, ecosystem, rainfall and the immunity of the state's inhabitants come under threat.

The projections made in the study indicate that the state will see higher average temperatures which will worsen the quality of life for native flora and fauna, and increase the number of heat-related illnesses for residents and visitors. Warmer oceans and higher ocean acidity will trigger massive bleaching, and marine migration, while decreasing trade winds will disrupt rainfall patterns across the state—leading to periods of drought and heavy rainfall.

Sea levels, which have risen by 0.5-1.3 inches per decade throughout the last 100 years, are also expected to accelerate, leading to a 1-3 foot rise by 2100. A sea-level rise of this magnitude will put parts of the state underwater.

There is no certainty regarding when these projections will become a reality. However, the impact of climate change is already evident across the state. The uncertainty regarding these projections is due to two aspects:

i.) We don't know how greenhouse gas emissions will evolve worldwide. This is the biggest source of uncertainty.

ii.) Global Climate Models simulate the Earth's entire physical environment. This simulation might not be able to capt exhaustively all phenomenons happening on Earth (some of which remain relatively unknown, such as interactions between clouds and climate forcing.)

The beach erosion on the north shore of Oahu is a common example.

Ecosystems: Hawaii, the Endangered Species Capital of the World

Endangered Pacific Hawaiian damselfly (Megalagrion pacificum). Photo Credit: Dan Polhemus/USFWS

Hawaii has one of the richest ecosystems in the world. Its snow capped peaks are more than 12,000 feet high, and the outer islands are home to some of the largest seabird colonies across the world.

Around 25% of the species found on the US list of endangered species are endemic to Hawaii. This is why it is regarded as the endangered species capital of the world. Climate change is one of the main contributors to the loss and endangerment of species in the region.

The estimated increase in temperature and the changes in precipitation have worsened an already precarious situation. For example, species (such as the endangered i’iwi) that used to survive in the higher forests across the state’s islands, are now under increased risk of extinction if temperatures soar high enough to allow mosquitoes—transmitters of species killing diseases—to move further up the mountains.

Trees and forests are not left out. They are adapted to specific climatic conditions, and with the warming of the climate, the forests will change. These changes could bring about transformations in geographic range, species composition, productivity as well as resilience to pests and diseases.

Climate change will, therefore, not only put endangered species closer to extinction but also reduce the current range and density of forests—causing them to be replaced by grasslands and pasture.

Hawaii Is Running out of Time

Kii (image) stands at Honaunau Bay, Pu`uhonua O Hōnaunau National Historical Park in Hawaii. According to a recent study, over 500 cultural sites in the state will be flooded or eroded if sea levels rise by the projected 3 feet by 2100. Photo Credit: sodai gomi

With the various studies sanctioned and various actions taken, the state of Hawaii has shown awareness of the threat of climate change in the region. However, climate analysts believe that the state is running out of time to prevent some of the worst impacts of climate change.

According to this study, structures and lands worth more than $20 billion are expected to be flooded if sea levels rise by the projected 3 feet by 2100. Over 500 cultural sites in the state will be flooded or eroded, while 20,000 residents will be displaced. The study also shows that even moderate warming will force around 50% of the forest bird species across the state to lose more than half of their current range by 2100.

The bleaching of coral reefs, however, is one aspect of the report that is already here. They are expected to bleach annually starting from 2040, making a recovery almost impossible. With the death of the coral reefs, the marine life in the area will take a hit, and there will be reduced coastal protection.

Corals cover 38% of the ocean area in Hawaii. The figure is expected to drop to 11% by 2050 and 1% by 2100. The study places the economic loss as a result of losing the corals to $1.3 billion per year in 2050, rising to $1.9 billion by 2090.

If the world meets the Paris agreement, it would delay bleaching by about 11 years and help the state save millions of dollars. For longer-term respite, however, climate scientists suggest that the world needs to do more than the agreement.

Principal Impacts of Climate Change in Hawaii

Hawaii monk seal and turtle napping. Warmer oceans have led to increased coral bleaching and outbreaks threatening the marine ecosystem. Photo Credit: Mark Sullivan for NOAA

Climate change will affect various aspects of everyday life in Hawaii.

  1. The rising air and ocean temperatures, as well as the changes in the rainfall patterns and the ocean chemistry, will have a negative effect on the people and the ecosystem of the region.
  2. Rising sea levels will worsen coastal flooding and erosion while damaging infrastructure, coastal ecosystems, and agriculture.
  3. Low-lying portions of high islands—which hold most of the state’s airports and road networks-will be affected heavily by rising sea levels. The vulnerability of the ports and airports and roads is of great concern because the islands in the area are dependent on imported fuel, food and material.
  4. The rising temperature and the reduction in precipitation will reduce the amount of freshwater available for drinking and for agriculture.
  5. Warmer oceans have led to increased coral bleaching and outbreaks threatening the marine ecosystem.

Hawaii's Waikiki Beach Could Soon Be Underwater

Waikiki beach in Oahu, Hawaii. Losing the beach will cost the state around $2 billion in yearly tourism revenue.

One of the findings of the 2017 Hawaii Climate Commission report  is the fact that the popular Waikiki beach in Oahu is in danger of being underwater over the next 15-20 years as a result of rising sea levels. Losing the beach will cost the state around $2 billion in yearly tourism revenue. To fight the problem, the state’s Senate and House of Representatives passed a measure designed to address threats facing the region.

The Cost of Climate Change in Hawaii

Major economic hubs in Hawaii such as Waikiki and the airport could lose thousands of dollars due to sea level rise and flooding.

The 2017 Hawaii Climate Commission report  was the first time the state connected the science of climate change to economic consequences. Its estimate of $19 billion lost to the flooding of structures and lands led the state government to request for assessments and strategies for addressing the challenge across various city departments.

The tourism sector will be one of the hardest hit as the impacts of climate change continue. For example, ocean recreation companies are currently worried about the prospects of losing the $520 million revenue from scuba diving alone, as rising water temperatures continue to decimate the cauliflower corals across the state. Other constituents of the tourism industry will also see similar losses.

The state’s Board of Water Supply has 76 miles of pipeline in the flood zones, as highlighted by the report, which is vulnerable to water corrosion. The cost of updating these pipelines has been set at around $300 million.

The state’s Department of Transportation has also noted that 15% of the state’s highway system, bridges and general infrastructure have to be raised or relocated to avoid some of the worst impacts of climate change. The preliminary estimate of this has been placed at $15 billion.

Building for Climate Change in Hawaii

Climate Change Adaptation: Designing for Change

Climate change is affecting the conversation about how buildings are designed and constructed in Hawaii. Although there is still some uncertainty on whether builders should construct new projects to withstand 3 or 6 feet of rise in sea levels, many of them are already taking action. For example, emergency generators are no longer installed on the ground floor, and new buildings are now elevated.

Some engineers are also advocating for the use of adaptive engineering techniques. With this approach, buildings will be designed to be easily modifiable in the future to counter climate change impacts. An example of this approach is to build flood control walls with a foundation that is strong enough to support making the wall taller in the future.

The flexible design approach could be a solution that many builders will embrace because the cost of erecting structures that will be able to withstand the effects of climate change in 75 years today, is prohibitive. Builders are also looking to the government for more guidance on regulations and codes.

Hawaii’s Climate Change Adaptation Policy

Hawaii has implemented several policies geared towards climate change adaptation. Act 234, Session Laws of Hawaii 2007 is the state’s benchmark policy framework to address GHG emissions. House Bills 2182 and 1986 were introduced, with the goal of making Hawaii a carbon-neutral state by 2045.

The bills add to the deadlines that already exist for 2045. It is the year earmarked by state law as the deadline for generating electricity from 100% renewable sources and also the deadline for the elimination of fossil fuels from their ground transportation fleets across the state.

Hawaii’s climate change adaptation policy means it could be fossil-fuel free and carbon-neutral by 2045, and prepared to face the impacts of climate change. However, this is dependent on the level of action taken.

Hawaii’s Concrete Plan

The Hawaii Department of Transportation (HDOT) is working with a new concrete mix injected with carbon dioxide to not only improve infrastructure but to help the environment.

In 2019, the Hawaii Department of Transportation (DOT) announced plans to use carbon-injected concrete in all construction as part of its climate change adaptation solution. It approved the use of the material in all flat constructions such as roads, and sidewalks and is already testing it for use in vertical projects. The material is stronger and more workable and is not costlier than traditional concrete.


Hawaii is one of the states that will be most affected by climate change. However, the impact on the region will be felt by the world as our ecosystem and biodiversity will be worse off if all the worst projections become a reality.

The state has implemented various climate adaptation initiatives, but a lot more needs to be done to ensure it comes out on top in this race against time. The actions taken in the next few years will determine just how badly the changing climate will alter the Aloha state’s landscape.

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