HONOLULU (HawaiiNewsNow) - Global warming is real, it's happening here in Hawai'i and humans are mostly to blame – those are the findings according to the latest international climate change report authored by more than 800 scientists from 39 countries, two of them from the University of Hawai'i at Manoa.
The Intergovernmental Panel on Climate Change (IPCC) is a scientific body endorsed by the United Nations to provide assessments about the risk of climate change, and its potential environmental and socio-economic consequences.
Dr. Axel Timmermann and Dr. Mark Merrifield, both Oceanography professors at UH Manoa, were selected for one phase of the IPCC's climate assessment program on the physical science basis of climate change.
Fellow professors, colleagues and students packed into the Daniel K. Inouye Center for Microbial Oceanography: Research and Education (CMORE) Hale on campus today for a presentation on the IPCC's most recent assessment report, and what it means for Hawai'i.
Scientists say our world is rapidly warming and more than 50% of the rise in the global mean temperature since the 1950's is caused by humans.
"All of the impacts of climate that are human-induced are driven by population, so if we had fewer people on the planet, it would have a lower impact, but that's something that's not really palatable for the average government," said David Karl, the Director of CMORE and a Professor of Oceanography at UH Manoa.
"We are living on a planet where human kind is making an impact," Karol explained.
Here in Hawai'i the biggest impact of global warming is the projected rise in our sea level. Experts say it's inevitable – but just how much, depends on what action we take.
"If we do nothing and if we keep going the way we're going, the sea level will be something like two to three feet higher than it is today by the end of the century. If we make a concerted effort to cap our emissions and to actually reverse the trend, we could see something like a foot of rise by the end of the century," described Dr. Mark Merrifield, a contributing author for an IPCC AR5 chapter on Sea Level.
With an animated graphic on display behind him, Merrifield explained to the audience what could happen to Waikiki and the Kaka'ako area when sea levels start to rise. He says at the very least high tide flooding will become much more frequent.
"It's not clear what's going to happen to say Waikiki Beach, how much sand's going to be on the beach – so obviously a big impact for tourism and for just the local community," said Merrifield, the Director of the UH Manoa Sea Level Center and Director of the Joint Institute of Marine & Atmospheric Research.
Climate change won't just impact water levels, but what happens below the surface as well. Scientists say about 30% of all CO2 emitted into the atmosphere is absorbed by the oceans, which increases acidification.
"I know that this means additional stress for example to corals, to any quantified organism in the ocean, so basically you have the effect of pH lowers calcification rates and that may lead to changes in our coral reefs, that may lead to changes in the ecosystem," explained Dr. Axel Timmermann, lead author for an IPCC AR5 chapter on Paleoclimate.
Experts say CO2 emissions – or greenhouse gases, which come primarily from the combustion of fossil fuels – are 40% higher than pre-industrial times. IPCC scientists want to keep global temperatures from rising above 2 degrees Celsius above the pre-industrial levels, and believe to limiting carbon emissions to 1,000 gigatons or below will hopefully prevent "dangerous climate change".
"Currently, we have already emitted about 540 gigatons of carbon so we're at least halfway there, so we do not have much more actually to reach this limit, so if we want to stay below this limit we have to implement strategies that would lower the CO2 emissions so that integrated over time we stay below 1,000 gigatons," explained Timmermann, who is also a professor at the International Pacific Research Center.
IPCC researchers are not policy makers, they simply provide the scientific basis to help inform governments and lawmakers, who must then decide what action to take.
"It's very easy to dismiss observations as being non-scientific but when an authoritative group like that IPCC makes an assessment report and makes these conclusions, I think it's time for the world to pay attention," said Karl.