(CN) --- The scale of the drought hitting the American West is beginning to crystallize as Nevada, New Mexico and Arizona experienced their driest year in terms of precipitation on record, according to the National Center for Environmental Information.
In Utah and California, it was the second-driest winter on record. For Wyoming, it was the third-driest ever. For Colorado, only three winters were ever drier in the 127-year history of record-keeping at the center.
“This is extreme,” said Peter Gleick of the Pacific Institute.
The U.S. Drought Monitor released a report Thursday that showed dryness covers approximately 50% of the contiguous United States, an unfortunate moment of historical proportions according to climate and weather experts.
"The drought monitor has been around for more than two decades, and we have only seen four springs where we've seen more than 40% drought coverage in the lower 48 states," said Brad Rippey, USDA meteorologist. "For the record, those years were 2000, 2003, and then in the wake of the big 2012 drought with the spring of 2013."
Rippey helps write the weekly report on conditions in the United States.
In the American West, about 97% of the territory is experiencing some form of dryness while about half of the land is witnessing either “extreme” or “exceptional” drought, the worst categories.
The problem throughout the American West in particular is a lack of snowfall the past winter and with summer on the horizon, there is little relief in sight.
“Only parts of the Pacific Northwest and areas of central Montana experienced near and above-normal seasonal snowfall,” the report states. “However, above-normal temperatures over much of the West over the past 60 days has resulted in rapid snowmelt and, due to dry topsoil, much of the meltwater has not made it into the rivers, lakes, and reservoirs.”
Lake Tahoe’s water level is a full 2.5 feet below where it was a year ago.
In California, the snowpack that historically melts incrementally throughout the summer --- replenishing the state’s complicated system of reservoirs, channels and canals --- is almost nonexistent.
“It's at 2% of normal for what it should be in late May,” Gleick said. “This means lower flows, hotter water, which kills endangered salmon, and more fire danger.”
The National Snow and Ice Center tweeted Wednesday that snow cover is the lowest the agency has seen since it began using satellites to track snowpack in the Sierra Nevada.
“On average, California snowpack supplies about 73% of the state's water needs,” the center said on Wednesday. “Snow cover now is the lowest in the 21-year satellite record. The state has already placed water restrictions in northern counties, more may come.”
California Governor Gavin Newsom has pledged to spend $5 billion to address water shortages throughout the state. He has declared a drought emergency in 41 of the state's 58 counties and more declarations are likely on the way.
Sonoma, Lake, Marin, Napa and Mendocino Counties were added to areas experiencing “exceptional drought” conditions, the worst category in the latest report.
Marin County’s water district is preparing its customers for the need to build a pipeline across the Richmond-San Rafael Bridge to siphon water from other places for the first time since the late 1970s.
In New Mexico, officials are urging farmers to hold off planting crops, warning the water allotments will be effectively nil.
An increasing body of research points to climate change as the culprit in increasing dryness in the American West.
Researchers from the University of California, Irvine published a study in Nature Communications this week that shows an increase in emissions is creating prolonged periods of dryness in the American West.
"There has always been natural variability in drought events around the world, but our research shows the clear human influence on drying, specifically from anthropogenic aerosols, carbon dioxide and other greenhouse gases," the study's lead author Felicia Chian said in a press release.Follow @@MatthewCRenda
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