Glacier could tell about Nevada’s future
It may surprise some residents of this desert state that is often afflicted with drought that there is a glacier in the Great Basin. It is located at the base of Wheeler Peak. And it’s feeling the heat.
Wheeler Peak, located in Great Basin National Park, reaches 13,063 feet, and the glacier is at about 11,500 feet. Much of the surrounding terrain—including the horn-like peak, nearby valleys and some lakes—was likely shaped by the glacier.
As a tourist attraction, the glacier is frustrating. It is not visible, and some people have drawn from this that it no longer exists. “It’s gone,” said a hiker to the Las Vegas Sun in 2015. Compared with the beautiful photos people are accustomed to seeing of ice glaciers, Wheeler Peak’s rock glacier can’t be photographed because it is essentially underground.
Scott Reinemann, geography professor at Ohio’s Miami University, and his colleagues are trying to get a better fix on the size of the glacier. It’s usually described vaguely as around 120,000 square feet in size
“The research group I am a part of has been researching in the Great Basin National Park for over a decade now,” he said. “We have more recently taken interest in mapping the area the rock glacier in the park covers.”
The National Park Service reports,, “The small glacier below Wheeler Peak has been incorrectly called an ice field. According to definition, an ice field is a vast body of ice, the union of several alpine glaciers. Ice fields are found today in Alaska and British Columbia. It has correctly been referred to as a rock glacier, however. A rock glacier is a lobe of angular boulders and cobbles that resembles an alpine glacier in outline and in its slow downslope movement. They are found in mountain ranges throughout the world. Inside a rock glacier, ice fills the spaces between the blocks. By freezing, thawing, and sagging, the ice works with gravity to provide the force that moves the rock glacier.”
The Wheeler Peak glacier is unusually far south for the western hemisphere. In addition to trying to measure the glacier, scientists have been using lakes to identify trends, and they think they can show a warming trend that began about four decades ago.
In a 2011 article for Park Science, Reinemann and five colleagues (Nathan A. Patrick, Gretchen M. Baker, David F. Porinchu, Bryan G. Mark, Jason E. Box) wrote, “Alpine and subalpine aquatic ecosystems are highly susceptible to direct and indirect effects of climate change, making them ideal study sites. We recovered a sediment core spanning the last 7,000 years from Stella Lake and a core of the last 100 years from Baker Lake in Great Basin National Park, Nevada, in 2005 and 2007. We examined the cores for subfossil chironomid (Insecta: Diptera: Chironomidae; i.e., midge) remains. The midge communities in the lakes underwent little compositional change through much of the 20th century; however, after 1980 a rapid lake-specific faunal turnover was observed.”
If the jargon is getting in the way, they are saying that around 1980 the insect life in the lakes began changing, with mites called midges that were adapted to cold dying out and warmer-adapted types moving in.
The isolation and relatively unknown beauty of Great Basin National Park is an aid to the scientists, giving them a study setting that is largely undisturbed. Not always, though. This is from the same article, with emphasis added:
“We installed a micrologger network to record hourly observations of surface air temperature and humidity. … The Lascar sensor network spans the full park elevation range (1,639–3,982 m or 5,377–13,063 ft) and includes sensors located at Baker (3,214 m/10,545 ft), Brown (2,976 m/9,764 ft), Stella (3,123 m/10,247 ft), and Teresa (3,132 m/10,276 ft) lakes. We analyzed data from autumn 2006 to autumn 2010. Data recovery has been limited at the uppermost elevation at Wheeler Peak (3,982 m/13,063 ft) because of vandalism to the sensor. Throughout the park, annual air temperature ranges are extreme, approaching 50°C (90°F). The temperature ranges at the lakes were 40°C (72°F) or more. We find that temperature and humidity decrease with increasing elevation.”
There may be another value to the study of the glacier. Communities in the Great Basin rely on snow melt for their water supplies, and finding out more about melt at the glacier can provide more information on the implications of climate change for growth. While no one can draw broad conclusions yet, the glacier study may be useful down the road.
“At this point, it is hard to classify the degree of the melt at the rock glacier, as it is not your typical type of glacier you see in images of Alaska and the Sierra Nevada of California,” Reinemann said. “A rock glacier is by definition the last remnants of a once much larger glacier, and at this site that was probably a glacier thousands of years ago.”
The Natural Resources Conservation Service this week issued its latest report on snowpack: “February snowpack percentages are 26-50 percent of median across most of the region. Since January 1, snowpack percentages have continued a gradual decline and are now in the realm of recent drought years like 2012, 2014 and 2015. In the Lake Tahoe, Truckee, Carson and Walker basins, current snow amounts are slightly better than 2015, while for the Humboldt Basin and Eastern Nevada there is less snow than 2015. SNOTEL data indicates that the Upper Humboldt has its lowest February 1 snowpack since these stations were installed in 1979. The Lower Humboldt is fourth lowest and Eastern Nevada is third lowest. Based on history, other years with snowpacks this low on February 1 were unable to recover to normal April 1 levels.”
As for rainfall, “Monthly precipitation in January was 50-70 percent of average across most of northern Nevada and the eastern Sierra basins. As of February 1, water year to date precipitation since October 1 is below average for Nevada ranging from 44 percent in eastern Nevada to 83 percent in the Owyhee River Basin. This is the driest start to a water year in eastern Nevada since SNOTEL sites were installed in 1981. The Lake Tahoe, Truckee, Carson and Walker basins have received between 63-80 percent of average, while the Humboldt basin has had 74 percent.”