Measuring Fluxes of Ammonia and Other Trace Gases Using Eddy Covariance and Relaxed Eddy Accumulation
September 23, 2010
Jay Ham (CSU Crop and Soil Sciences)
Hosted by Jeff Collett
“when you cannot measure it, ..., your knowledge is of a meagre and unsatisfactory kind”
-- William Thomson Kelvin, 1883
Measurement of energy and mass exchange in the surface boundary layer is fundamental to many research projects in atmospheric science. Eddy covariance (EC) and conditional sampling techniques (e.g., Relaxed Eddy Accumulation, REA) can obtain near continuous flux data from relatively small sampling footprints across the landscape. While these micrometeorological techniques are widely used to measure CO2 and H2O fluxes,new technologies are allowing flux measurement of many different compounds. At CSU, research is underway to develop tower-based systems for measuring ammonia and methane emissions from strong agricultural sources along Colorado's Front Range, specifically cattle feedlots. Results will compliment ongoing transport modeling and air quality research that examines how ammonia from livestock operations may be affecting nitrogen deposition in Rocky Mountain National Park and the Eastern Slope. Methane data will help quantify the role of beef production in the greenhouse gas emissions inventory.