What will Climate Change mean to Alaska?
Climate change describes the variation in Earth's global and regional atmosphere over time. These changes are likely caused by a combination of natural processes and activities. The rise in the Earth's average surface temperature is known as global warming. Scientists attribute the accelerating rate of global warming to manmade greenhouse gas emissions.
Global warming is currently impacting Alaska and will continue to impact it a number of ways. These impacts include melting polar ice, the retreat of glaciers, increasing storm intensity, wildfires, coastal flooding, droughts, crop failures, loss of habitat and threatened plant and animal species.
According to NOAA (National Oceanic and Atmospheric Association) scientists, 2010 tied with 2005 as the warmest year of the global surface temperature record, beginning in 1880. This was the 34th consecutive year with global temperatures above the 20th century average. Also noted by NOAA:
- The Arctic sea ice extent had a record long growing season, with the annual maximum occurring at the latest date, March 31, since records began in 1979.
- Despite the shorter-than-normal melting season, the Arctic still reached its third smallest annual sea ice minimum on record behind 2007 and 2008.
- NOAA's 2010 Global Highlights
Less ice means more open water - which means greater absorption of solar energy - which leads to increased warming in the ocean, and in turn accelerates more ice loss. This has led to a wide range of impacts in Alaska, including:
- melting glaciers, rising sea levels, and flooding of coastal communities. Warming of oceans and melting of land-based ice increases the volume of ocean water. Loss of sea-ice cover changes habitat for arctic species and leaves coastal communities more exposed to larger waves generated by severe storms.
- thawing permafrost, increased storm severity, and related infrastructure damage to roads, utility infrastructure, pipelines and buildings. Extremes in weather patterns, precipitation and rising sea levels will affect safe water sources in villages, and contributes to increased erosion along Alaska coasts and rivers and undermines Alaska boreal forests.
- loss of the subsistence way of life as animal habitat and migration patterns shift and as hunting and fishing become more dangerous with changing sea and river ice. Warming streams and increased silt from melting glaciers affect fish habitat. Boreal forests advance northward and to higher elevations, displacing tundra. Invasive species compete with native vegetation. Humans, animals and plants may be exposed to new infectious diseases as habitat changes.
- forest fires and insect infestations increasing in frequency and intensity. In the past decade, Alaska has witnessed a record loss of forests to fires and spruce bark beetles.
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