HR: 0800h
AN: A51E-0135    [Abstracts]
TI: Measurements of Anthropogenic Pollution in and Above the Marine Boundary Layer During ICARTT by Multi-Axis and Long-Path DOAS
AU: * Hurlock, S C
EM: steveh@atmos.ucla.edu
AF: University of California Los Angeles, Department of Amospheric and Oceanic Sciences 7127 Math-Sciences Building, Los Angeles, CA 90095-1547 United States
AU: Pikelnaya, O
EM: olga@atmos.ucla.edu
AF: University of California Los Angeles, Department of Amospheric and Oceanic Sciences 7127 Math-Sciences Building, Los Angeles, CA 90095-1547 United States
AU: Trick, S
EM: strick@atmos.ucla.edu
AF: University of California Los Angeles, Department of Amospheric and Oceanic Sciences 7127 Math-Sciences Building, Los Angeles, CA 90095-1547 United States
AU: Stutz, J
EM: jochen@atmos.ucla.edu
AF: University of California Los Angeles, Department of Amospheric and Oceanic Sciences 7127 Math-Sciences Building, Los Angeles, CA 90095-1547 United States
AB: Pollution transport in coastal environments can occur in and above the marine boundary layer (MBL). Pollution in the MBL can be detected and measured by ground based measurements and it is thus well understood. Pollution above the MBL, in contrast, is more difficult to monitor and requires aircraft or LIDAR measurements. In recent years a new technique, Multi-Axis (MAX) Differential Optical Absorption Spectroscopy, has emerged that allows the detection of pollution layers in the boundary layer and in the free troposphere. MAX-DOAS measures direct and scattered sunlight collected from various viewing directions, and its simple experimental setup makes it an ideal tool for the monitoring of pollutants such as NO₂ and HCHO over long time periods. Here we present simultaneous measurements of the UCLA LP-DOAS and MAX-DOAS instruments during ICARTT 2004 in the polluted marine environment of the Gulf of Maine. The LP-DOAS measured along a 2.3km light path above the ocean, while the MAX-DOAS scanned at five elevation angles parallel to the LP-DOAS light path. Pollution events in the MBL were identified by both instruments, allowing a validation of the new MAX-DOAS technique. Based on comparison of results from the two instruments, we will discuss examples of layers of aerosol, NO₂, and HCHO that were detected by MAX-DOAS at elevation levels above the marine boundary layer. During these events, pollution from the North-American continent was transported aloft, undetected by instruments probing only the MBL.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005