Mountain West Snow May Disappear for Years At A Time
December 03, 2021
A new study warns that there may be water supply shortage due to snowless mountains brought on by climate change.
The study by Nature Reviews Earth & Environment paints a grim picture for the Western US if the greenhouse gas emission remains unchanged, as there could be dire water shortage due to snowless mountains in the next 35-60 years. Since the 1950s, the region has already lost 20% of the snowpack, which is the same volume as Lake Mead. The snow cover across the US is only about 6%, which is the lowest since the records began in 2003.
The study’s authors state that there could be disastrous consequences in the upcoming decades as the snowless mountains could cause serious water shortage to the region.
Snowpack is also peaking and melting off earlier and is projected to continue in that trajectory. Atmospheric rivers are also heating and producing more rain than snow, which increases the chances of flooding.
Despite the past year not being a low snow year for California, the abnormally warm spring caused less snow to reach the reservoirs. According to a report by the California Department of Water Resources, California’s climate is shifting to a warmer status, in which historical relationships among temperature, precipitation and runoff are altering.
The extreme Pacific Northwest heat wave made snow loss evident in June. Alan Rhoades, a hydroclimate research scientist at Lawrence Berkeley National Laboratory and a co-lead author of the study, said “When the heat wave occurred, there was a sharp ablation of the snowpack … that water was ‘lost’ to dry soils and/or the atmosphere rather than feeding streams and rivers.”
Western states had only seen a glimmer of is to come. 2015 was an extremely low snow year in Sierra Nevada when the peak snowpack was only 5% of the normal amount. According the study, such years are projected to last for about 5-10 years at a time and nearly 78%-94% of the Western US could be snowless by the turn of the century.
A near-snowless 10-year period could be witnessed in the Sierra Nevada. Erica Siirila-Woodburn, a research scientist at Lawrence Berkeley National Laboratory and a co-lead author of the study, said “We don’t have any historical analogues of this persistent snowpack loss.”” She adds, “That, hydrologically, is a totally different beast.”
The authors see the study as a directive for scientists, water managers and policymakers as the snowpack will almost undoubtedly continue to shrink. The authors believe that these are steps that can be taken now to create a difference.
The former director of the Colorado Water Conservation Board and a Western Water expert, James Eklund, expressed his disappointment that not all water managers are approaching the issue quickly. He goes on to elaborate, “They are all aware things could be bad, but they haven’t planned for things to be this bad. This is an existential threat to the West and our water managers stand on the front lines of our response.” He continues to explain that the new climate change reality will not be cheap or easy and the municipalities and water districts must accept this reality. He also emphasized that senior water rights holders need to be paid to preserve the water in the river and leave it to delay and buy time until they get recycled water frameworks in place.
In spite of the grim picture the study illustrated throughout, it ends off on a positive note with a number of possible strategies and ways forward. Storing excess ground water acquired during wet years and reserving unutilized water from reservoirs could help compensate for the times with low snowpack storage. Enhanced climate forecast could help reservoir operators decide when to release and hold off water, avoiding unnecessary releases.
James Eklund, the Colorado water expert, says that the good news is that we can do this and hope is not a strategy. He continues by saying that we have to act quickly and failure is not an option.