Global Warming

The conclusion that most scientists have come to regarding the effects of global warming on Washington might not be a surprise based on the dry winter of 2005. In January 2005, our snowpack was the lowest it has been in 28 years, resulting in closed ski resorts and abnormally low river flows. Although by most expectations 2005's weather will remain a rare occurrence, the consensus is that our region will experience gradually increasing temperatures over the coming decades.

CELP Signs on to an Amicus Brief

Global warming is a real threat to Washington's rivers and streams. Increased warming means less snow in the mountains and therefore less water in the rivers for salmon, kayakers, and those who appreciate the beauty of a mighty river. CELP has signed onto an amicus brief asking the U.S. Supreme Court to overturn a lower court decision that allowed the EPA to forego its duty to regulate greenhouse gas emissions. The National Wildlife Federation drafted the brief and released this press statement.

Background

The various climate-modeling systems predict an average change of 3.36 degrees (Farenheit) within the next 70 years. This warming is not unprecedented: already as a result of a rise in global temperatures, 75% of the western United States has seen a reduction in mountain snow. Although the ultimate effects that these climate changes will have on the environment are still unknown, current research is beginning to paint a picture of the problems Washington State will likely face in coming decades.

The snowpack in the Cascade Mountains is a primary source of water storage in Washington State, and snowmelt during the spring and summer is what keeps Washington's streams and rivers flowing during these otherwise relatively dry months. A study by the Center of Water Resources Management and Drought Planning at the University of Washington suggests that the direct result of an even small increase in temperature warming will be a decrease in snowpack. Even though they predict a slight increase in precipitation, the snowpack will decrease due to an increased percentage of the precipitation falling as rain, a lower snowline and snow melting earlier in the year. As a result, our snowpack could drop by 59% in the next 50 years under even the most conservative warming scenarios. Because of these snowpack changes, the peak flow levels in our streams and rivers will tend to come earlier, shifting from May to as early as March.

This trend towards an early peak in water levels poses a serious threat to Washington's water resources, and is the largest effect that global warming will have on the Pacific Northwest. Because of these earlier flows, there will be substantially less (35-50%) water during the summer months to meet the needs of people, farms, fish, and energy production. Salmon, whose lifecycles are linked closely with seasonal changes in rivers and streams, could be seriously affected by a shift in seasonal flow patterns.