Snowpack is melting fast, despite April storms

It has dwindled faster than experts have seen in nearly four decades, which could upset reservoir management.

 

Throughout late March and into April, much of the West experienced unseasonably warm days. Then, in late April, temperatures plummeted in Southwest Colorado’s San Juan Mountains and more than 2 feet of wet, heavy spring snow fell. Suddenly, ski boots were out again and for a day or two, it felt like winter was back.

But those storms have only helped a small fraction of the West, with much of the moisture buoying snowpack levels along the Eastern Rockies in Colorado and Wyoming. Meanwhile, the rest of the region is on the opposite trajectory, losing snowpack at record-breaking rates.

At the beginning of April, snowpack levels across the region were “near normal,” says Cara McCarthy, deputy director for the National Water and Climate Center in Portland, under the Natural Resource Conservation Service. The season was off to a slow start with sporadic storms in October through December, but January winter precipitation increased levels across all states, according to NRCS SNOTEL sites, which measure snow depth at thousands of stations nationwide. For months, most of the region hung on to above-normal snowpack measurements.

But in just the few short weeks since, that snow is melting faster than climate hydrologists have seen in nearly four decades, bringing the snowpack far below normal in most states in the West.

High temperatures and low moisture in most of the region has diminished snowpack — more quickly than hydrologists have seen happen in a one-month period in nearly four decades.
NRCS, National Water and Climate Center.

For states already struggling with dwindling water, the quick retreat of snowpack may affect how much water resource managers can store in nearby reservoirs. For California, in its fifth year of drought, this season has been a bit of a rollercoaster. In January, snowpack readings increased to 127 percent of normal (up from 90 percent in December) — good news for a state where 30 percent of the water supply is dependent on snow.

But now California’s three most crucial basins for the state’s water supply are far below normal: The Northern Sierra is at only 66 percent normal for late April, Central Sierra is at 64 percent of normal and the Southern Sierra is at 49. “This should be a bit of a wake-up call for water resource managers,” McCarthy says. 

Temperature has been a major factor in the accelerated melting, although minimal snowfall has also played a role. According to the NRCS and National Oceanic and Atmospheric Administration, much of the Pacific Northwest, California, Idaho and Montana have experienced abnormally high temperatures between the beginning throughout April — in some places departing from historical averages by as much as 10 degrees Fahrenheit. Colorado and parts of New Mexico and Arizona have been more or less normal.

The quickly diminishing snowpack, which acts as a natural water-storage system for Western cities that depend on winter snow for water, portends a more variable future at the whims of a changing climate, says Noah Diffenbaugh, associate professor at Stanford and a research at the Woods Institute for the Environment.

“We find that as warming continues, there’s a robust response of the climate in the West toward more rain and less snow,” Diffenbaugh says.

Water infrastructure has been built around the assumption that a reasonable quantity of water will remain as snow at higher elevations until the temperature warms. As warming occurs earlier in the season and snowpack diminishes faster, it runs into reservoirs prematurely and resource managers may need to release water to make space available to prevent floods. 

According to a 2015 study that Diffenbaugh co-authored, the basins of the arid American West are among the most climate-vulnerable on the globe. The Colorado River Basin, for example, which supplies water to 40 million people in seven states, will likely suffer as snowpack disappears. The Northern and Central California basins, fed partially by the Sacramento and San Joaquin rivers, are also vulnerable to climate shifts.

From a water management perspective, the snowpack readings so far this year are troubling, but they may start to feel normal in coming decades. According to the Intergovernmental Panel for Climate Change, the climate is on track to warm 4 degrees Celsius by the end of the century. If that happens, what we consider “extreme” now — rapid, early spring snowpack melt — “will happen more like 40 to 80 percent of the time,” Diffenbaugh says. 

Paige Blankenbuehler is an editorial fellow at High Country News. She tweets

High Country News Classifieds
  • OPERATIONS DIRECTOR
    We are a Santa Fe-based nonprofit that builds resilience on arid working lands. We foster ecological, economic, and social health through education, innovation, and collaboration....
  • COMMUNITY ORGANIZER
    Come work alongside everyday Montanans to project our clean air, water, and build thriving communities! Competitive salary, health insurance, pension, generous vacation time and sabbatical....
  • CAMPAIGN MANAGER
    Oregon Natural Desert Association (ONDA), a nonprofit conservation organization dedicated to protecting, defending and restoring Oregon's high desert, seeks a Campaign Manager to works as...
  • HECHO DEPUTY DIRECTOR
    Hispanics Enjoying Camping, Hunting, and the Outdoors (HECHO) was created in 2013 to help fulfill our duty to conserve and protect our public lands for...
  • REGIONAL REPRESENTATIVE, COLUMBIA CASCADES
    The Regional Representative serves as PCTA's primary staff on the ground along the trail working closely with staff, volunteers, and nonprofit and agency partners. This...
  • FINANCE AND OPERATIONS DIRECTOR
    The Montana Land Reliance (MLR) seeks a full-time Finance and Operations Director to manage the internal functions of MLR and its nonprofit affiliates. Key areas...
  • DIRECTOR OF CONSERVATION
    The Nature Conservancy is recruiting for a Director of Conservation. Provides strategic leadership and support for all of the Conservancy's conservation work in Arizona. The...
  • EXECUTIVE DIRECTOR
    The Amargosa Conservancy (AC), a conservation nonprofit dedicated to standing up for water and biodiversity in the Death Valley region, seeks an executive director to...
  • BIG BASIN SENIOR PROJECT PLANNER - CLIMATE ADAPTATION & RESILIENCE
    Parks California Big Basin Senior Project Planner - Climate Adaptation & Resilience ORGANIZATION BACKGROUND Parks California is a new organization working to ensure that our...
  • CUSTOMER SERVICE ASSISTANT - (PART-TIME)
    High Country News, an award-winning media organization covering the communities and environment of the Western United States, seeks a part-time Customer Service Assistant, based at...
  • SCIENCE PROJECT MANAGER
    About Long Live the Kings (LLTK) Our mission is to restore wild salmon and steelhead and support sustainable fishing in the Pacific Northwest. Since 1986,...
  • HUMAN RESOURCES GENERALIST
    Honor the Earth is an affirmative action/equal opportunity employer and does not discriminate based on identity. Indigenous people, people of color, Two-Spirit or LGBTQA+ people,...
  • DEVELOPMENT DIRECTOR
    Colorado Trout Unlimited seeks an individual with successful development experience, strong interpersonal skills, and a deep commitment to coldwater conservation to serve as the organization's...
  • NEW BOOK BY AWARD-WINNING WILDLIFE BIOLOGIST, BRUCE SMITH
    In a perilous place at the roof of the world, an orphaned mountain goat is rescued from certain death by a mysterious raven.This middle-grade novel,...
  • DESCHUTES LAND TRUST VOLUNTEER PROGRAM MANAGER
    The Deschutes Land Trust is seeking an experienced Volunteer Program Manager to join its dedicated team! Deschutes Land Trust conserves and cares for the lands...
  • PROGRAM DIRECTOR
    Now hiring a full-time, remote Program Director for the Society for Wilderness Stewardship! Come help us promote excellence in the professional practice of wilderness stewardship,...
  • WYOMING COMMUNITY PARTNERSHIPS COORDINATOR
    The Theodore Roosevelt Conservation Partnership is seeking Coordinator to implement public education and advocacy campaigns in the Cowboy State to unite and amplify hunter, angler,...
  • MOUNTAIN LOTS FOR SALE
    Multiple lots in gated community only 5 miles from Great Sand Dunes National Park. Seasonal flowing streams. Year round road maintenance.
  • RURAL ACREAGE OUTSIDE SILVER CITY, NM
    Country living just minutes from town! 20 acres with great views makes a perfect spot for your custom home. Nice oaks and juniper. Cassie Carver,...
  • A FIVE STAR FOREST SETTING WITH SECLUSION AND SEPARATENESS
    This home is for a discerning buyer in search of a forest setting of premier seclusion & separateness. Surrounded on all sides by USFS land...