Can We Take the Heat?

This graph shows the projected timing of ‘climate departure’ for Hawai‘i when our annual average temperature will exceed the historical bounds of past temperature variability (shaded grey). Hawai‘i is projected to reach climate departure by 2023 under a high greenhouse gas concentration scenario (red), and by 2050 under a moderate scenario (yellow). Source: Mora et al 2013.

In its fifth report on the physical science of global climate change, the Intergovernmental Panel on Climate Change concludes that warming of Earth’s climate system is unequivocal and most of the temperature increases since the mid-20th century is “extremely likely” caused by increased concentrations of greenhouse gases from human activities. The last three decades were the warmest since 1850, and the last 30 years were likely the warmest 30 years in the last 1,400 years.

In terms of research specific to Hawai‘i (by Safeeq, Giambelluca, and Keener et al), air temperature has exhibited a consistent increasing trend over the last 100 years, the rate of which has quadrupled in the last 40 years to over 0.3° F per decade. If the world continues to emit greenhouse gases the way we have been (dubbed the “business as usual scenario”), by the year 2085, temperature will have increased by a range of 4° to 5° F.

Dr. Camilo Mora and others from the University of Hawai‘i recently calculated when we will start experiencing a climate we have never experienced before (using 1860 through 2005 as the historical period), i.e. the “climate departure.” Under “business as usual,” Hawai‘i is expected to experience average air temperature extremes exceeding the historical annual maximum by the year 2023! If emissions decrease to a more intermediate level (dubbed Representative Concentration Pathway 4.5) this would occur later, in 2050. Either way, it’s going to get hotter in our own lifetime, bringing more risk of disease, extreme heat vulnerability, wildlife habitat impacts and others.

Ruby Pap

Mora’s sobering report also shows that the timing of the “climate departure” is earlier for the tropics and low income countries, pointing to the need for developed countries, the highest emitters of greenhouse gases, to make serious reductions now. Those in areas most impacted will need to put serious funding toward social and conservation programs to minimize the impacts.

Back at Niumalu, toward the end of the program Ben Sullivan (County of Kaua‘i) and Jan TenBruggencate (Kaua‘i Island Utility Cooperative) spoke of the aggressive efforts on Kaua‘i to reduce greenhouse gas emissions — highlighting that it is up to all of us to do our part — and every little bit counts. I would like to personally thank Apollo Kaua‘i for hosting and rallying so many interested community members. Apollo will continue to hold monthly meetings, and is encouraging the public to get involved.

Visit apollokauai.com for more information.

• Ruby Pap is a Coastal Land Use Extension Agent at University of Hawai‘i Sea Grant College Program. She can be reached at rpap@hawaii.edu.