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
  • WYOMING OUTDOOR COUNCIL OFFICE MANAGER - BOOKKEEPER
    The Wyoming Outdoor Council is seeking an office manager-bookkeeper to join our team. The office manager-bookkeeper supports the program and administrative functions of the Wyoming...
  • HEALTHY RIVERS SENIOR STAFF ATTORNEY
    WRA seeks a passionate attorney to join our Healthy Rivers team. The Senior Staff Attorney will research and advocate for wiser water management and updated...
  • CONSERVATIONIST? IRRIGABLE LAND?
    Stellar seed-saving NGO is available to serious partner. Package must include financial support. Details: http://seeds.ojaidigital.net.
  • CONSERVATIONIST? IRRIGABLE LAND?
    Stellar seed-saving NGO is available to serious partner. Package must include financial support. Details: http://seeds.ojaidigital.net.
  • PROGRAM MANAGER
    Applications will be reviewed on an ongoing basis and will be accepted until: February 03, 2020. Overview Conservation Voters for Idaho (CVI) protects Idaho's environment...
  • WRITING SKILLS TUTOR FOR HIRE!
    Fort Collins, CO college students welcome. Meet on your college campus!
  • CANYONLANDS FIELD INSTITUTE
    Colorado Plateau Natural & Human History Field Seminars. Lodge, river, hiking options. Small groups, guest experts.
  • NATURE EDUCATION DIRECTOR
    Our mission is to inspire a life-long connection to nature and community through creative exploration of the outdoors. We are seeking an educational leader who...
  • REALTOR NEEDS A REMOTE ASSISTANT
    This is a business assistant position, The working hours are flexible and you can chose to work from anywhere of your choice, the pay is...
  • EXECUTIVE DIRECTOR
    Central Oregon LandWatch is seeking an Executive Director to advance our mission and oversee the development of the organization. Job Description: The Executive Director oversees...
  • WESTERN NATIVE SEED
    Specializing in native seeds and seed mixes for western states.
  • MEDIA DIRECTOR
    Love working with the media? Shine a spotlight on passionate, bold activists fighting for wild lands, endangered species, wild rivers and protecting the climate.
  • STAFF ATTORNEY - NEVADA
    The Center for Biological Diversity is seeking an attorney to expand our litigation portfolio in Nevada. Come join our hard-hitting team as we fight for...
  • EXECUTIVE DIRECTOR
    The Montana Wildlife Federation seeks an energetic leader to advance our mission, sustain our operations, and grow our grassroots power. For a full position description,...
  • HISTORIC COMMERCIAL OPPORTUNITY IN DOWNTOWN NOGALES
    Nogales. 3 active lower spaces and upper floor with lots of potential. 520-245-9000 [email protected]
  • CHUCK BURR'S CULTUREQUAKE.COM BLOG
    Change will happen when we see a new way of living. Thinking to save the world.
  • COMING TO TUCSON?
    Popular vacation house, furnished, 2 bed/1 bath, yard, dog-friendly. Lee at [email protected] or 520-791-9246.
  • DIRECTOR, TEXAS WATER PROGRAMS
    The National Wildlife Federation seeks a Director to lead our water-related policy and program work in Texas, with a primary focus on NWF's signature Texas...
  • SPLIT CREEK RANCH
    Spectacular country home on 48 acres with Wallowa River running through it! 541-398-1148 www.RubyPeakRealty.com
  • OJO CALIENTE COMMERCIAL VENTURE
    Outstanding location near the world famous Ojo Caliente Mineral Spring Resort. Classic adobe Mercantile complete w/living quarters, separate 6 unit B&B, metal building and spacious...