Filters: Tags: CO2 flux (X)3 results (70ms)
An automated system for continuous measurements of trace gas fluxes through snow: an evaluation of the gas diffusion method at a subalpine forest site, Niwot Ridge, Colorado
An experimental system for sampling trace gas fluxes through seasonal snowpack was deployed at a subalpine site near treeline at Niwot Ridge, Colorado. The sampling manifold was in place throughout the entire snow-covered season for continuous air sampling with minimal disturbance to the snowpack. A series of gases (carbon dioxide, water vapor, nitrous oxide, nitric oxide, ozone, volatile organic compounds) was determined in interstitial air withdrawn at eight heights in and above the snowpack at ~hourly intervals. In this paper, carbon dioxide data from 2007 were used for evaluation of this technique. Ancillary data recorded inlcuded snow physical properties, i.e., temperature, pressure, and density. Various vertical...
CO2 flux and soil temperature measurements at the Shady Rest thermal area, Mammoth Lakes, California, 2010-2019
The Shady Rest thermal area (SRST) is characterized by elevated soil temperatures and CO2 emissions and associated vegetation kill. The site is located about 3 km northwest of the Casa Diablo geothermal power plant at Mammoth Lakes, California. The elevated soil temperatures and CO2 emissions are related to changes in the shallow hydrothermal system caused by geothermal fluid production. During late 2006 changes at the Casa Diablo geothermal power plant included installation of 2 new production wells near SRST. Fluid production from these wells resulted in the expansion of areas of existing thermal ground, development of new thermal ground and an increase in the number of tree kills. Between 2006 and 2019 the USGS...
Process-level controls on CO2 fluxes from a seasonally snow-covered subalpine meadow soil, Niwot Ridge, Colorado
Fluxes of CO2 during the snow-covered season contribute to annual carbon budgets, but our understanding of the mechanisms controlling the seasonal pattern and magnitude of carbon emissions in seasonally snow-covered areas is still developing. In a subalpine meadow on Niwot Ridge, Colorado, soil CO2 fluxes were quantified with the gradient method through the snowpack in winter 2006 and 2007 and with chamber measurements during summer 2007. The CO2 fluxes of 0.71 ?mol m?2 s?1 in 2006 and 0.86 ?mol m?2 s?1 in 2007 are among the highest reported for snow-covered ecosystems in the literature. These fluxes resulted in 156 and 189 g C m?2 emitted over the winter, ~30% of the annual soil CO2 efflux at this site. In general,...