Global Warming Cuts Water Snowpack Storage by 56 Percent in Oregon

The climate is changing, causing some areas to dry out while others cope with wetter conditions. As these shifts occur, scientists are attempting to predict exactly what we might expect in the future. In the case of Oregon, though, it turns out that there will be an average 56 percent drop in the amount of water stored in peak snowpack by the middle of this century. This could have significant impacts for the surrounding regions that rely on this source of water.

In order to find out how rising temperatures might affect snowfall and snowpack, the researchers examined what kind of precipitation levels the region might see in the future. Precipitation could be either higher or lower, so the scientists calculated changes that could range 10 percent in either direction.

So what did they find? It turns out that as far as snowpack goes, temperature is the driving force--far more than precipitation. Even the highest level of anticipated precipitation had almost no impact on the snow-water storage. Since temperatures are projected to rise about 3.6 degrees Fahrenheit, this finding is crucial for understanding how the region copes. Warmer temperatures mean that there will be less snow and more rain, which could change the ecosystems in Oregon.

"In Oregon we have a water-rich environment, but even here we will have to manage our water resources differently in the future," said Eric Sproles, the leader of the study, in a news release. "In the Willamette River, for instance, between 60 to 80 percent of summer stream flow comes from seasonal snow above 4,000 feet. As more precipitation falls as rain, there will be more chance of winter flooding as well as summer drought in the same season. More than 70 percent of Oregon's population lives in the Willamette Valley, with the economy and ecosystems depending heavily on this river."

This phenomenon doesn't just impact Oregon, though. It could extend to regions anywhere in the world that have low-elevation snow in mountains. This includes places such as Japan, New Zealand and Northern California. The findings show that water management will be crucial in the future as snow continues to disappear.

The findings are published in the journal Hydrology and Earth System Sciences.