A new study by the USGS suggests that the snowpack on the Rocky Mountains is dwindling due to warmer spring temperatures.
The findings suggest a snowpack decline along the "entire length" of the Rocky Mountains, with notably high declines in the north.
Scientists came to the conclusion after observing snowpack variations dating back 800 years.
While the exact cause of the warming is unknown, researchers believe it may be due to a mix of natural fluctuations in temperature as well as human activity.
"Each year we looked at temperature and precipitation variations and the amount of water contained within the snowpack as of April," said lead author and USGS scientist Greg Pederson in a statement.
"Snow deficits were consistent throughout the Rockies due to the lack of precipitation during the cool seasons during the 1930s – coinciding with the Dust Bowl era. From 1980 on, warmer spring temperatures melted snowpack throughout the Rockies early, regardless of winter precipitation. The model in turn shows temperature as the major driving factor in snowpack declines over the past thirty years."
Runoff from the Rocky Mountain is an invaluable resource, accounting for roughly 60 to 80% of the annual water supply for more than 70 million people in the U.S.
The full study can be read online at Geophysical Research Letters.