Warming Temperature Blamed for Record Low Snowpack Levels in West Coast

A new study reveales that the record low snowpack levels in the western-most region of the continental U.S. last 2015 were most likely caused by high temperature.

The study, published in the journal Geophysical Research Letters, showed that the warmer temperature in the west coast has become the primary driver of the low snowpack levels in the region. Previously, warmth was only the secondary driver of low snowpack, following dry winter. However, the higher temperature in 2015 has become the primary culprit in reducing the snowpack levels.

"The 2015 snowpack season was an extreme year," said Philip Mote, director of the Oregon Climate Change Research Institute at Oregon State University and lead author on the study, in a press release. "But because of the increasing influence of greenhouse gases, years like this may become commonplace over the next few decades."

For the study, the researchers run regional climate simulations in tens of thousands citizen computers in a sort of crowd-sourced supercomputer. The researchers run three different simulations with different scenarios. The first simulation was run using actual sea surface temperatures and greenhouse gas emissions from December 2014 to September 2015. The second simulation was made with lower greenhouse gas levels corresponding to the pre-industrial era, and teased out the impacts, while the third set of simulations used modern greenhouse gases but removed the unusual pattern of sea surface temperatures in 2014-15.

The researchers discovered that 81 percent of their measurement sites in the west coast experienced record low snowpack levels due to the warmer temperatures. These sites include f California, Oregon, Washington, western Nevada and western Idaho. The researchers claim that the greenhouse gases were a major contributor to the high temperatures.

During the study period, the researchers recorded 6.5 degrees Fahrenheit warmer than average temperature in Oregon. Oregon, as well as California, recorded 90 percent below average overall snowpack level. Furthermore, about 111 of the measurement sites recorded zero snowpack levels for the first time in April 1, 2015.

With the Paris Agreement to take effect this November, this study has once again showed the importance of cutting back the emissions of greenhouse gases as an initial step in hindering future increase in the global average temperature.