Elk Mountain Observatory
(contact: Jeff Snider, University of Wyoming, Atmospheric Science, jsnider@uwyo.edu)

Updated 9 Sept 08

Overview -

The Elk Mountain Observatory is unique because of its frequent exposure to clouds.  Clouds and high wind speeds result in strong vertical gradients of cloud droplets and ice crystals at the mountain/atmosphere interface. The site is therefore ideal for examining interactions between cloudy atmospheres and the alpine environment.  Because of climatological similarities to regions located at high latitude, processes studies at the Elk Mountain can also be used to better understand polar atmospheric processes and polar land/atmosphere interactions.   For details, please see the attached references and figures.

Research -
Research conducted at Elk Mountain has consisted of the following themes: 1) ice particle nucleation and growth in mountain wave clouds (Cooper and Vali, 1981; Rogers and Vali, 1987), 2) atmospheric sulfur dioxide oxidation to sulfate (Snider and Vali, 1994), 2) trace gas volatilization from ice (Snider and Murphy, 1995; Snider and Huang, 1998), 3) deposition uptake of low molecular weight alcohols into ice (Huffman and Snider, 2004), 4) atmospheric deposition to alpine tundra soils (Snider and Vali, 1987; Lokupitiya et al., 2000), 5) light attenuation by atmospheric aerosols (Han et al., 2003), and 6) characterization of aerosol size distributions (Cai et al., 2008).

Site Description -
The Elk Mountain Observatory is located at the northern end of the Medicine Bow Mountain range in southeastern Wyoming. The Observatory consists of a main building located at the head of Halleck Creek in a small semi-circular basin (10,850 ft), and the Schaefer Hut located atop the western peak of Elk Mountain (11,000 ft).  A short grass prairie dotted with cattle and sheep ranches surrounds Elk Mountain.  Aspens grow in the transition between the prairie and the upper slopes of the mountain, Lodge Pole pine forests extend from 8,000 to 9,000 ft, sub alpine fir and spruce up to 10,500 ft, and tundra dotted with patches of spruce occur above 10,500 ft.  Elk Mountain and the surrounding mountain summits are immersed in clouds with a frequency of 30% during the winter months and 3% during summer (Snider and Garcia, 1989).

Access -
The Elk Mountain Observatory is located on property owned by the Department of Atmospheric Science and the University of Wyoming. The Department operates Tucker Snow Cats which are used for wintertime travel from the base of the mountain to the Observatory. The mountain access road crosses several privately owned land sections and the University pays an annual access fee to The Elk Mountain Ranch Company. During summer, approximately 3 hours is required to travel from Laramie to the Observatory.

Facilities -
The facility is supplied with line power and the Observatory heating system is electric powered.   There is a small wind tunnel, a cold room, kitchen and bathroom facilities, and living space for six.

References -
Cai, Y., D.C.Montague, W.Mooiweer-Bryan and T.Deshler, Performance characteristics of the ultra high sensitivity aerosol spectrometer for particles between 55 and 800 nm: Laboratory and field Studies, J.Aerosol Sci., 39, 759-769, 2008, PDF

Cooper, W.A., and G.Vali, The origin of ice in mountain cap clouds, J. Atmos. Sci., 38, 1244-1259, 1981, PDF
Huffman, W.A. and J.R.Snider, Ice-oxyhydrocarbon interactions in the troposphere, J. Geophys. Res., 109, D01302, doi:10.1029/2003JD003778, 2004, PDF.

Han, Z., D.C.Montague, and  J.R.Snider, Airborne measurements of aerosol extinction in the lower and middle troposphere over Wyoming, USA,  Atmos. Env., 37, 789-802, 2003, PDF

Snider, J.R., and  J.Huang, Factors influencing the retention of hydrogen peroxide and molecular oxygen in rime ice, J. Geophys. Res., 103, 1405-1415, 1998, PDF

Snider, J.R., and T. Murphy, Airborne hydrogen peroxide measurements in supercooled clouds,  J. Geophys. Res., 100, 23039-23050, 1995, PDF

Lokupitiya, E., N.L. Stanton, R.S. Seville, and J.R. Snider, Effects of increased nitrogen deposition on soil nematodes in alpine tundra soil, 44, 591-608, Pedobiologia, 2000, PDF

Rogers, D.C., and G.Vali, Ice crystal production by mountain surfaces, J. Clim. Appl. Meteor., 26, 1152-1168, 1987, PDF

Snider, J.R., and G. Vali, Sulfur dioxide oxidation in winter orographic clouds, J. Geophys. Res., 99, 18713-18733, 1994, PDF

Snider, J.R., D.C.Montague, and G.Vali, Hydrogen peroxide retention in rime ice, J. Geophys. Res., 97, 7569-7578, 1992, PDF

Snider, J.R., and A. Garcia, Summertime cloud immersion frequency at Elk Mountain, Wyoming. in Effects of Air Pollution on Western Forests, Editors R.K.Olson and A.S.Lefohn, 1989

Snider, J.R., and G. Vali, Rime ice composition at the Elk Mountain Observatory: Atmospheric processes, acid and nutrient deposition rates. in Chemical Quality of Water and the Hydrologic Cycle. Editors. D.McKnight and R.C.Averett. Lewis Publishers.  Chelsea, Michigan, 1987

Figure 1 - Land ownership in the vicinity of Elk Mountain.

Figure 2 - The Elk Mountain Observatory and facility buildings.

Figure 3 - Inside the Observatory; Jim Waldram, Don Lukens and Larry Oolman.

Figure 4 - Matt Burkhart (ATSC), Barbara Carrapa (UW Geology and Geophysics), Jeff Snider
(ATSC). Western summit, July 2007.

Figure 5 - Medicine Bow River valley and Elk Mountain from the northeast, July 2003.