Rocky Mountain Regional Snowpack Chemistry Monitoring Study Area: High-elevation sites near the Continental Divide in Montana, Wyoming, Idaho, Colorado, New Mexico, and Utah, 1993 to present
Study Area: Continental Divide in Montana, Wyoming, Utah, Idaho, Colorado,
and New Mexico
Additional information is available on the expanded project website.
Snowpacks collect atmospheric deposition throughout the snowfall season and offer a unique opportunity to obtain a composite sample of the chemistry of most (roughly November through April) of the annual precipitation at high elevations (> 1800 meters). This project was created to sample the full snowpack at selected sites to determine sources of acid deposition to sensitive mountain watersheds. Since 1993, the project has become the most expansive and comprehensive snowpack-chemical monitoring network of its kind. Beginning with sampling fewer than 20 sites in Colorado in 1993, the network has expanded to greater than 50 locations along the Continental Divide that have been sampled each year since 1993. In the process, techniques have been developed that use robust tracers to separate and quantify local and regional sources of atmospheric deposition of airborne pollutants. Through this program, long-term trends (>20 years, generally) are being developed in snowpack chemistry that enable estimation of normal or background levels, and identification of elevated chemical concentrations at a variety of locations where atmospheric deposition of acidic compounds is a concern. The project primarily monitors federally-managed lands in the Rocky Mountain region including several protected wilderness areas in National Forests and Parks. Applications of this regional snow-chemistry work include identifying regional trends in chemical concentration and deposition as well as monitoring subregional or local effects including power-plant emissions in Colorado or snowmobile usage in Yellowstone and other areas.