Carbon Dioxide and other greenhouse gases have occurred naturally in the Earth’s atmosphere since the beginning of Earth’s existence.  These gases reflect some of the sun’s rays back to the Earth, keeping the atmosphere at the temperatures needed to support life.  However, humans have pulled large quantities of solid carbon in the form of coal and fossil fuels from deep within the earth, and through burning have released them as carbon dioxide gas into the air.  In a short period of time, this burning of fuels has altered the concentration of these gasses in our atmosphere.  As a result, greater quantities of the sun’s rays are being reflected back to the Earth and the Earth is getting warmer. 

This warming can cause many different effects in the Pacific Northwest.  Already, Washington has seen the disappearance of 53 glaciers since the 1950’s (http://www.ecy.wa.gov/pubs/0711016.pdf.) The glaciers of the Cascades, as well as our winter snow pack, provide water to much of both sides of the Cascades.  The melting could result in water shortages for these areas.  As the forests of Washington become warmer, they will also get drier, making it harder for new tree seedlings to get established and increasing our risk of catastrophic forest fire.  Sea level rise, caused by thermal expansion and land ice melt, will affect much of Washington’s coast line.  For more information on the causes and effects of global warming, see Climate Solutions’ website.