Washington Glaciers Are Losing Ground to Climate Change

Glistening sheets of alpine ice sheer across mountain flanks and pool in crevices throughout the North Cascades range. Over 300 glaciers and countless snowfields make these Washington mountains one of the snowiest places on earth, and home to the greatest number of glaciers in the lower 48 states of the U.S.. The North Cascades’ 400 to 700 inches of snow each year sustain these low-elevation glaciers.

Such high country reservoirs of ice and snow, known as the “cryosphere,” store as much water as all of the state’s streams, rivers, and lakes combined. They release around 230 billion gallons of water each year for irrigation, salmon fisheries, and hydroenergy, in addition to household use for nearly eight million Washington residents.

Climate change is altering these frozen regions and affecting Washington’s communities, economies, and environment, according to the Climate Impacts Group at the University of Washington.

“We are seeing the consequences (of warming), even at the local level,” said Amy Snover, director of the Climate Impacts Group at the University of Washington. “The impacts are only expected to worsen over time.”

Glacial loss impacts the region in myriad ways. In the notoriously rainy Pacific Northwest, water is scant during summer months. Glaciers provide equilibrium, building up stores of snowpack during winter and spring and releasing it during low precipitation months. Nature’s water system has been a good bet until climate change began to alter the balance. 

Spring snowpack has declined about 30 percent from 1955 to 2016, and peak streamflow is coming earlier in the year – up to 20 days earlier in 2002 compared to 1948. The glacial area of the North Cascades has decreased by more than 56 percent since 1900. In the North Cascades, glacier loss is gaining speed. All 47 monitored glaciers are retreating, and three have disappeared entirely.  

Glacial melt leads to changes in soils and vegetation. Melting ice releases pollutants into mountain lakes and streams where they enter the food chain, and it discharges greenhouse gases into the atmosphere. Habitat is lost for specialized organisms that provide nutrients to fish, amphibians, birds, and mammals, laying risk to biodiversity.

Glaciers are almost lifelike in their constant movement and change. They sculpted the North Cascades with repeated blankets of ice, and now they are changing the terrain, both natural and human, as the ice retreats. Glacial melt threatens freshwater stores, raises sea levels, alters river systems, and brings economic consequences to industries as diverse as tourism, agriculture, and energy. Future scenarios for green gas emission projects these changes will increase, stressing downstream ecosystems and the communities that rely on them.