the long winter: record-breaking winter Provides busy season for nrcs snow surveyors Heather Emmons and Jeff Anderson State Public Affairs Officer and Hydrologist, USDA-NRCS
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he autobiographical children’s novel “The Long Winter,” by Laura Ingalls Wilder, is also an appropriate title for an article about this winter’s snowpack accumulation. After multiple years of drought and one average winter in 2016, snow surveyors experienced a real challenge in 2017. Deep snow in the Sierra made for time consuming and strenuous sampling at snow courses (Figure 1 and 2)). Extra helicopter flights, snowmobile rides and hikes were needed to visit NRCS automated snow telemetry, or SNOTEL, sites to keep them collecting quality data despite what has turned into a record year at some locations. According to NRCS Hydrologist Jeff Anderson, the Mt. Rose Ski Area SNOTEL site reached an all-time snow water record in early April (Figure 3). A measurement on April 10 indicated 206 inches of snow depth and 89 inches of water content. That means the snow is 17 feet deep and contains nearly 7.5 feet of water. Anderson said, “At Mt. Rose SNOTEL, a ‘normal’ winter that is 100 percent of the median peaks at 37 inches of water content, so this winter brought well over two winters worth of snow to the area.” With social media hashtags of “#Januburied” and “#Flooduary” being bantered around to describe the weather, the obvious question many are asking is: is 2017 the biggest winter ever? In the Lake Tahoe, Truckee, Carson and Walker basins, the 2017 snowpack ranks among the top handful of years. April 1 snow water contents are similar to amounts measured in epic winters like 1952, 1969, 1983 and 1995. Anderson points out, “Up high is where we are seeing new records. A number of sites above 8,000 feet did set new records.” For the rest of Nevada outside the Sierra, the answer to that question about 2017 being the biggest winter is simple: no. “Compared to the recent past, this winter was very good for areas east of the Sierra, even better than 2011, but not close to record amounts,” said Anderson. “Based on daily SNOTEL data, other years such as 1983, 1997 and 2006 had more snow.”
A Little History: From Dr. Church to NRCS The Year 1910: The Lake Tahoe region is the birthplace of snow surveying and home to the oldest snow courses in the world. Dr. James Church, a classics professor at the University of Nevada in Reno, made the first surveys on Mt. Rose in the Sierra Nevada, where he installed the first snow course in 1910. He developed measuring equipment and sampling techniques that led to the first water supply forecasts. The Year 1935: The Dust Bowl resulted in farmers demanding better predictions of the streamflows available for growing crops. Others who counted on water for industry, power generation, and domestic use echoed this request. Congress responded in 1935 by passing legislation creating a federal snow survey and water supply forecasting program under the direction of the Bureau of Agricultural Engineering in the Department of Agriculture. In 1939, the bureau was transferred to the Soil Conservation Service (SCS); this agency, now known as the Natural Resources Conservation Service (NRCS), continues to direct a cooperative federal, state, and private snow survey program. The NRCS collects snow data using snow courses and SNOTEL sites, but what is the difference between these? Snow courses were established first. Many snow courses in Nevada have been measured for more than 70 years. They involve a marked transect – two posts on either end, with a series of points on a line. Snow tubes are used to core the snow, to measure its depth and water content each month during the winter. SNOTEL sites are automated weather stations that replaced many snow 34 JULY/AUGUST 2017
courses starting in the late 1970s. These sites report snow depth and water content, as well as precipitation and other variables. SNOTEL data is transmitted every hour and available to the public on the internet. The Year 2017: The “Long Winter” was capped off on April 1, 2017 when Jeff Anderson and NRCS snow surveyor Jessica Gwerder measured a new all-time record at Dr. Church’s first snow course. Anderson said, “It was a thrill to set a record back to the earliest days of snow surveying. I’ll be framing that field note for my wall.” The measurement of 156 inches snow depth and 81.8 inches of water content was 243 percent of median. This is the most snow water ever measured at this snow course back to 1910 when Dr. Church made the first measurement. Leading up to this historic measurement, 2017 has had other highlights. January 2017, tagged as “#Januburied” on social media, will go down as one of the biggest monthly payouts to western Nevada’s water supply of all time. The Tahoe, Truckee, Carson and Walker basins got a whole winter’s worth of snow in about three weeks. Ski resorts reported up to 300 inches (25 feet) of snowfall in this time. Rain and snowmelt in early February caused the 21-mile dam in northeastern Nevada to breach, flooding Montello. The same storm started flooding in western Nevada and along the Humboldt River. The Humboldt flooding took most of February to reach Winnemucca. Social media responded to these events with the hashtag “#Flooduary.” A second wave of Humboldt River flooding ran the length of the river in March. Throughout the winter, the NRCS uses the data it collects to publish the Nevada Water Supply Outlook Report. This report is posted online and emailed to subscribers the first week of each month from January through May. Not only are the reports timely, but they’re also rich in data. The following is a summary from the April 1, 2017 report. Contact Jeff Anderson at jeff.anderson@nv.usda.gov if you would like to be added to the subscription list.
Figure 1. Jeff Anderson, NRCS Nevada hydrologist, measures the snowpack at the Mt. Rose SNOTEL site on March 1, with assistance from NRCS District Conservationist Jim Gifford (right).
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