Several professionals gathered at the state capitol Thursday for an informational briefing to alert people to the immediacy and magnitude of the threat that climate change poses to Hawaii.
Senate Committee on Agriculture and Environment Chair Mike Gabbard and West Hawaii Rep. Nicole Lowe, chair of the House Committee on Energy and Environmental Protection, hosted the presentation.
“Climate change has been misunderstood, downplayed, or even denied by many people — and denial does not make a problem go away, it just forestalls any action and makes the problem worse,” said Gabbard. “To address a problem, we must first recognize that the problem exists and then understand its scope, scale and timing. Therefore, the purpose of this informational briefing is to bring public attention to the immediacy and magnitude of climate change.
“We need everyone’s help to do the long, hard work of countering climate change as much as we can, mitigating it where we can and adapting to it as well as we can.”
State Climatologist Pao-Shin Chu discussed the impact of climate change on hurricanes and drought in Hawaii.
He said during El Nino years when trade winds weaken and ocean waters warm, there are typically more tropical cyclones and hurricanes in the Central Pacific. As the Earth’s temperature rises, these storms will become stronger.
“Conclusion from a study of the Northeast Pacific including Hawaii, there is essentially no change in the number of storms, but an increase in storm intensity and rainfall, 20% higher than present,” he explained.
However, based on models, he expects to see more storms impacting Hawaii in the future and a shift toward an earlier onset of storms. Hurricane season in Hawaii is currently from June to November.
He also explained that during an El Nino cycle, there is less rainfall and more sunshine, which brings on droughts, usually from November to March.
“Spring and summer after El Nino sees more wildfires,” he said. “Drought became more widespread and intense in the most recent decades, particularly in the last 20 years.”
Dr. Charles “Chip” Fletcher, interim School of Ocean and Earth Science and Technology dean, said 2023 was hottest year on record.
“Heat domes form from unstable jet stream because of warming of the arctic. The jet stream is slowing. June thru August sits way outside the trends of previous years. We see extremely hot daily temperatures,” he said. “Sea surface temperatures in 2023 sat above everything in last 40 years.”
He said global sea ice is far below levels from any previous recorded year.
“Scientists are speculating we are seeing an acceleration of global warming. Every month from June to December was the hottest ever recorded,” he said. “The Paris agreement was set to stop warming at 1.5 degree C, however Co2 has increased, and we are on tract to warm nearly 3 degree C.”
Victoria Keener, co-lead of the Pacific Regional Integrated Sciences &Assessments Program said the National Climate Assessment — released every four years localizing climate risk — shows the change exacerbates inequities and threatens ecosystems, cultural resources, human health, livelihoods and access to water and food.
She said in Hawaii, the number of hot days per year has increased dramatically. Temperatures have risen by 0.76 Fahrenheit over the past 100 years.
“Hawaii rainfall has been trending downward for decades, with the sharpest decrease in West Hawaii. Projections show more decrease in rainfall,” she said. “Climate impacts are being felt now and adaptation is critical at local scales. We need to mitigate and adapt because it is only going to get worse in the coming decades. Climate change impacts access to healthy food and water. Food security is negatively impacted by rising temperatures and sea level rise.”
She said 82% of heat-related deaths in Honolulu are attributed to climate change.
Wildfires also are increasing because of climate change, she said.
“The wildfire area burned has increased fourfold from the early 1990s, impacting native ecosystems,” she explained. “But Indigenous knowledge systems strengthen island resilience. Local interventions can mitigate some amount of climate risk. Greenhouse gas needs to be cut 28% by 2030 to keep within the 2 degree rise in temperature.
In addition, she said rising sea levels threaten infrastructure and local economies and exacerbate existing inequities.
“Responses to rising threats may help safeguard tropical ecosystems and biodiversity,” she said. “We are at a global turning point in the global energy system. Renewable energy grew by 50% last year. Oil and gas production continue to increase. We are in a sustainability transition.
“We must engage in adaptation and mitigation and be equitable in underserved communities through public health, affordable housing, education, water resources, overconsumption and disease. Sea level rise is an unstoppable reality because of warming oceans.”
Models show a rise of sea level up to 6 feet by 2100. As sea level rises, there is groundwater inundation which brings polluted water to the surface.
“When it rains, we have compound flooding. Add high tide and storm drains are filled with sea water.”
John Bravender, Central Pacific Hurricane Center Meteorologist, said in an average year there are four to five tropical cyclones, but in 2015 the area had 16.
“Model simulation shows formation shifting northward, causing increase in threat of making landfall in Hawaii,” he said. “As ocean water gets warmer, we will see longer hurricane season. We can help mitigate the issues as we plan for the conditions. But going on past history is not enough. Building codes have changed over the years. Older homes can be retrofitted. We need to think ahead.”
Tammy Lee from the Department of Transportation said her department is focused on long-term viability of the transportation infrastructure.
“Flooding due to sea level rise was studied. In the state, 10 airports would be impacted, ” she said. Based on preliminary studies, we need to elevate runways or retrofit facilities at least 1 foot above the projected sea level rise over the next 100 years, or move airports inland.”
She also discussed the vulnerability of the state’s ports.
“98% of goods comes through our ports. Harbors are vulnerable to sea level rise. Ports may need to raise structures. Erosion is also a concern,” she said.
Regarding coastal highways, she said it would cost about $15 billion to mitigate the effects of rising sea levels.
“Today’s briefing helped to ensure that chairs and committee members are up to date with the most current information about climate, and, hopefully will help educate the public on these issues as well,” said Lowen after the presentation.
