HR: 1340h
AN: A33A-0862    [Abstracts]
TI: The Naval Research Laboratory's High-Resolution (27km) Dust Source Database for Southwest Asia
AU: * Walker, A L
EM: walker@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Ave., Stop 2, Monterey, CA 93943-5502 United States
AU: Miller, S D
EM: miller@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Ave., Stop 2, Monterey, CA 93943-5502 United States
AU: Richardson, K A
EM: richardson@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Ave., Stop 2, Monterey, CA 93943-5502 United States
AU: Westphal, D L
EM: westphal@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Ave., Stop 2, Monterey, CA 93943-5502 United States
AU: Liu, M
EM: liu@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Ave., Stop 2, Monterey, CA 93943-5502 United States
AB: In the past, the Naval Research Laboratory's (NRL) regional weather model, COAMPS™, used the United States Geological Survey (USGS) land use characteristic dataset to determine dust emission areas. However, three major weaknesses in using the USGS dataset to specify sources have become apparent. 1. The land use characteristics of Southwest Asia have changed due to anthropogenic influences, drought, and climate change. 2. The land use classifications for desert regions are too broad. Most of Southwest Asia falls under the eight dust-producing categories, thus the entire region functions as a dust source. 3. The USGS derived one-degree database is too coarse to match the 9- and 27-km resolution nests of COAMPS™. As a result of these weaknesses in the USGS dataset, COAMPS™ tends to over-predict dust mobilization and detailed spatial features, such as plume heads and dust fronts, are not resolved. To overcome these issues, we have created a high-resolution (27 km) dust source database using satellite imagery, maps, atlases, and recently released governmental reports. In this paper we will describe the approach and methodology used in identifying dust sources for the high-resolution database. The primary tool used to locate dust emission areas in Southwest Asia is the NRL satellite derived Dust Enhancement Product (DEP). The DEP consolidates and extends previous satellite techniques to distinguish raised dust over land and water from the other components of the scene. When compared to standard visible satellite imagery (at 0.65 μm) the DEP readily reveals dust clouds previously undectable in true color imagery. The 1-km and 500-m resolution of the DEP allows us to identify individual plume heads (often measuring 10 km or less across) that merge to form larger plumes and clouds during dust events. An essential step in our identification process is cross-correlating these plume heads with geomorphological information to determine the location, extent and validity of each dust source before entry into the database. Improvements and differences in temporal and spatial resolution between the NRL dust source database and the USGS dataset will be given. The impact on dust forecasting using the high-resolution database will be shown in this and other papers in this special session.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 9320 Asia
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005