On Tuesday, Aug. 20, members of the Kihei Community Association (KCA) listened intently as Lauren Campbell discussed two hot topics--global warming and climate change. Campbell, a marine scientist and conservation manager for Pacific Whale Foundation (PWF), told attendees that she was there "to empower each and every one of you, but first we need to start with the basics."
The primary distinction between global warming and climate change is time, Campbell said.
Global warming refers to the Earth's 4.6-billion-year history of long ice ages punctuated with relatively brief warming trends or interglacial periods. For example, our last ice age, known as the Pleistocene, lasted approximately 1.5 million years. Around 10,000 years ago, the Earth entered into an interglacial event called the Holocene as a result of increased solar activity. As the ice sheets that covered North America and Eurasia gradually retreated, humans moved into areas once too cold for habitation.
In addition to serving as the conservation manager for the Pacific Whale Foundation, Marine Biologist Lauren Campbell, and climate expert, is also heads up the Maui Chapter of the Surfrider Foundation.
Apparently, this cycle of warming and cooling is completely natural, so what is all the fuss about?
Campbell said the Earth's ice helps reflect solar radiation constantly bombarding our atmosphere. But as the polar icecaps continue to retreat, our planet is losing this ability.
Today, Campbell said, the Earth's atmosphere simply has more energy in its system. As a direct result, it's getting hotter and our climate is changing.
"Climate refers to a 30-plus-year period of averaging weather patterns. Weather is a day-to-day experience," Campbell said.
While global warming may be a naturally reoccurring phenomenon, humans are responsible for adding to what are known as greenhouse gasses.
"A simple way to understand this dynamic is to park your car in the sun with the windows rolled up. In no time, the interior of the car becomes unbearably hot," Campbell explained.
This is because certain forms of solar radiation--specifically, infrared light waves--are being trapped.
Campbell said that in their natural form, greenhouse gasses are responsible for sequestering just enough heat for the Earth to be habitable. Other terrestrial planets in our solar system, such as Mars, lack this essential ability, so surface temperatures vary wildly from day to night. Since the industrial revolution commenced in the late 18th century, the continuous burning of carbon-based fossil fuels, along with the deforestation of much of the planet has unnaturally increased the amount of greenhouse gasses. Therefore, more of the sun's radiation in now being trapped in our atmosphere, so it's getting unnaturally hotter around the globe.
And as the atmosphere heats up so do our oceans.
"Sea level rise is not just a function of the polar ice caps disappearing, it also the result of thermal expansion as our oceans heat up the water actually expands," Campbell said.
For those of us living on islands--particularly near coastlines--sea level rise is a real concern.
As air temperatures increase, "normal" weather patterns are shifting. For example, on Maui we have experienced a decrease in our historic rainfall patterns, said Campbell.
According the U.S. Geophysical Society Pacific Island Water Science Center, "During May - July 2013, rainfall was about 58 percent of average. As of July 2013, rainfall at Pu'u Kukui, the summit of the West Maui Mountains, was below average eight of the last 10 months with complete rainfall records."
Less rainfall means reduced stream flow. Reduced stream flow negatively affects reef health and impacts near-shore fisheries. In addition to unseasonal droughts, Maui is also experiencing increased rain intensity, causing damaging flooding taxing the capacity of Maui County's emergency services.
Another immediate concern are the disease carrying mosquitoes now able to survive in Upcountry climates once too cold to sustain them, said Campbell. Because of this, many of Maui's native bird species may be infected by these pernicious pests and dangerous vectors of diseases.
So while global warming may be a natural process, anthropogenic carbon (that produced by humans) is definitely helping to speed things up," said Campbell. By reevaluating our own carbon footprint, we can collectively slow the process down and hopefully reverse this trend.
Current projections by the Intergovernmental Panel of Climate Change indicate in a best-case scenario a 2 to 5.2 degree rise in global temperatures and in a worst case a 4.3 to 11.5 degree rise.
Taking personal responsibility is one simple strategy, said Campbell. To see how you are impacting the environment, go to the Environmental Protection Agency's Website and use its Individual Greenhouse Gas Emissions Calculator.
Next KCA meeting is Sept. 17, at 6:30 p.m. at Kihei Charter School on Lipoa Avenue.
Access an application to join the 2014 KCA board of directors at www.gokihei.org.
Click on "Get Involved" at the top of the home page. Mail the application by Oct. 11 to Kihei Community Association, P.O. Box 662, Kihei, HI 96753.
For more information, call (508) 499-9996.