Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT)
15 February - 15 March 2011
Erie, CO 40.0500°N, 105.0039°W
Various instruments making measurements on Erie tower as well as ground-based instruments.
Investigators in this project include researchers from NOAA ESRL Chemical Sciences Division, the University of Colorado, the University of Washington, the University of Virginia, the University of Toronto, the University of New Hampshire, the National Center for Atmospheric Research, Colorado State University, and the Max Planck Institute.
Halogen species are extremely important in atmospheric chemistry, serving both as strong oxidants and as catalysts that drive the production and destruction of ozone. Recent field investigations have demonstrated that nitrogen oxides, common pollutants from combustion sources, are efficient at producing these halogens, particularly in the winter and during darkness. Little is known about this potentially important process for several reasons: There is limited atmospheric chemical data available from the winter season; the atmosphere is vertically stratified at night and during winter, such that surface level measurements aren't necessarily representative; finally analytical technology for the key species has been unavilable until recently. This study will provide vertically resolved measurements from a 300 m tower during winter. It will include recently developed, cutting edge measurements of the key halogen, nitrogen oxide, and aerosol species.