The Southeast Atmosphere Study (SAS) is a collaboration
that brings together resources and facilities from NSF, NOAA, EPA, and EPRI.
The SAS is the "umbrella" for the NOMADSS, SOAS, NAAMEX, TROPHONO, and SENEX projects.
SAS's main purpose is to ensure that the objectives of the individual projects
|The field phase for the SAS will be 1 June 2013 through 15 July 2013 and is generally focused in the southeastern United States. All airborne platforms (i.e., NSF/NCAR C-130, NOAA WP-3D, Purdue Duchess, and Stonybrook Long-EZ) and ground based facilities (i.e., Centreville and Alabama Aquatic Biodiversity Center (AABC), Alabama; Look Rock, Tennessee; and Research Triangle Park (RTP), North Carolina) are involved in the SAS. The individual project descriptions and objectives are described below.|
See site maps in Related Links Section below.
|The Nitrogen, Oxidants, Mercury and Aerosol Distributions, Sources and Sinks (NOMADSS) project integrates three proposed studies: the Southern Oxidant and Aerosol Study (SOAS), the North American Airborne Mercury Experiment (NAAMEX), and the TROPospheric HONO (TROPHONO).|
The merger of the SOAS, NAAMEX, and TROPHONO field campaigns on the C-130 platform provides the opportunity to address the objectives and science questions for the three respective projects summarized below.
NOMADSS Principal Investigator: Dan Jaffe, UW
|The SOAS objectives include the direct quantification of VOC, ozone and NOx surface fluxes and reconcile differences with "blank-down" emission estimates; better understanding of HOx/NOx/ozone/organics/aerosol distributions, sources and sinks.|
The primary goals for NAAMEX are to: (1) constrain emissions of mercury from major source regions in the United States, and (2) quantify the distribution and chemical transformations of speciated mercury in the troposphere. These goals will be fully met in the merged project. The merger represents a significant opportunity to conduct detailed sampling in the most concentrated Hg source region in North America as well as flights into the middle and upper troposphere where models suggest a significant source of oxidized Hg. The NOMADSS payload includes the key NAAMEX measurements, plus fast VOC measurements that will help in source identification. The data on HONO will provide an additional constraint on oxidation processes, which are poorly understood for Hg.
The objectives for TROPHONO are: (1) to establish HONO distribution and budget in various air masses (continental and oceanic background air masses, and urban/industrial plumes) in the troposphere; (2) to collect bulk aerosol samples for laboratory photochemical experiments to measure photolysis rate constant of particulate nitrate leading to HONO and NOx productions; (3) to quantify p-NO3 as a daytime HONO source and a re-NOx-ification pathway in the troposphere; (4) to examine HONO production from photo-enhanced heterogeneous NOx reactions in urban/industrial plumes; and (5) to investigate HONO dark formation/nighttime accumulation and morning-hour photolytic decay in the PBL and in the FT.
TROPHONO Principal Investigator: Xianliang Zhou, Wadsworth Center and SUNY Albany
The SENEX project goal is to use the NOAA P-3 aircraft to (i) to sample air masses that contain a different mixture of emissions (urban, power plant, forest), (ii) to follow these air masses as they are transported and chemically transformed in the atmosphere, and (iii) to measure the vertical distribution of trace gases and aerosol in the atmosphere, in order to answer five specific science questions:
SENEX Principal Investigator: Joost DeGouw, NOAANOAA SENEX Web Page