Although the one-degree increase in the Earth’s overall temperature in the last 50 years may not sound like enough to work up a sweat over, it’s enough to trigger erratic weather patterns, extinctions and increasing sea levels.
Alaska is absorbing a disproportionately large share of the Earth’s overall temperature increase and instead of climbing just one degree, Alaska temperatures have increased three to five degrees overall and seven to 10 degrees in the winter.
Last week Alaska residents gathered in Kenai to discuss the impacts of global warming in the state. They responded with a mixture pessimism and optimism after a presentation by Conservation Solutions President Deborah Williams.
Williams presented an alarming picture of how global warming is reshaping Alaska, but said although some change is inevitable, there still is time to avoid the worst.
Williams said she believes humans will come together to solve global warming problems, but that the window of opportunity for curbing greenhouse emissions is short.
“There is going to be some more warming even if we cap (emissions) now,” she said. “But we don’t have to get cataclysmic.”
Four gases trap heat from the sun in the atmosphere and prevent the Earth from freezing over — methane, carbon dioxide, CFCs and nitrous oxide. Since the industrial revolution, in the late18th and early 19th century, humans have created a 35 percent increase in the atmosphere’s carbon dioxide, the most significant heat-trapping gas.
“It’s like having a blanket that’s 35 percent thicker,” Williams said.
Major changes due to warming temperatures have already begun. In few places are those changes as apparent as they are in Alaska, she said.
Alaska’s climate is warming disproportionately fast primarily because as the Earth warms, Alaska’s ability to reflect heat radiating from the sun into space has declined, she said.
In Alaska rising temperatures have decreased the accumulation of reflective snow and ice, and, therefore, increased the amount of heat being absorbed.
Snow has a much greater albedo, ability to reflect, than does the ocean or soil. Snow and ice reflect 85—90 percent of the sun’s energy and the ocean and soil reflect only 10-20 percent. So as Alaska’s snow cover recedes it absorbs more heat, compounding the effects of global warming.
Williams’ presentation pointed to evidence of global warming on the peninsula, such as the results of recent stream monitoring study conducted by Cook Inlet Keeper and the Homer Soil and Water Conservation District. Research found that the four peninsula rivers and creeks studied exceeded temperatures considered healthy for salmon for a record number of days in 2005.
Also discussed as evidence of global warming was Skilak Lake’s decline as a nursery for salmon. In recent years, Alaska Department of Fish and Game biologists have measured decline in salmon fry growth in the lake and have attributed the decline to increased glacial meltwater entering the lake and clouding it with silt. Glacial silt blocks sunlight entering the lake, slowing the growth of algae and disrupting the food chain on which salmon fry depend.
In pointing to evidence of global warming Williams also mentioned the results of a study done in the Kenai National Wildlife Refuge, a study that suggests that the peninsula is seeing an increase in woody vegetation and becoming drier.
Using arial photographs and field samples the study presented data on how regions within the refuge had changed from 1950 to 1996 and found a 35 percent decrease in open areas, 88 percent decrease in wetlands and a 14 percent decrease in water and lakes.
Some of the more than 35 people attending the global warming discussion, held by the Center for Mediation and Community Dialogue, raised doubts about people’s willingness to respond to global warming problems.
Despite some discouraging observations, however, Williams radiated an infectious optimism.
“I really, really do believe change is possible,” she said. “If we get pessimistic, well, then Exxon wins.”
Williams, who once was the executive director of the Alaska Consumer Advocacy Program and of the Alaska Lung Association, likened the struggle to change attitudes toward climate change to changing attitudes toward smoking.
“Even though the tobacco industry had a lot of power, people figured it out,” she said. “This campaign is a little bit similar to tobacco ... another example of hope.”
