HR: 0800h
AN: A41D-06    [Abstracts]
TI: Microphysical Characteristics of Developing Tropical Cyclones During NAMMA 2006
AU: * Pratt, A S
AF: Howard University, 2355 6th Street NW, Washington, DC 20059, United States
AU: jenkins, G
AF: Howard University, 2355 6th Street NW, Washington, DC 20059, United States
AU: Heymsfield, A
AF: National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000, United States
AB: Aerosols interacting with clouds can have profound impacts on the microphysical structure of these clouds and can affect precipitation formation processes. A modeling study in the 1990's (Rogers et al 1994) noted that a 100- fold increase in ice nuclei (IN) concentration resulted in cloud water depletion and the prevention of homogeneous freezing in maritime cumulus cloud. Several studies conducted during CRYSTAL-FACE (DeMott et al 2003; Sassen et al 2003) noted IN concentrations 20-100 above normal values and glaciation of altocumulus clouds at unusually warm temperatures, both due to Saharan dust. Finally, Koren et al (2005) denoted changes in convective cloud properties due to the effects of aerosols. These effects, particularly on convective clouds, might be important for larger-scale processes, such as tropical cyclogenesis. The microphysical characteristics (liquid water content, particle concentration, etc.) of two developing tropical cyclones (Tropical Depression 8 and Tropical Storm Debby from the 2006 Atlantic Hurricane Season) will be presented. In particular, the possible effects of dust on the microphysics, as well as implications for cyclogenesis will be explored. These data were taken on board the NASA DC-8 during the NAMMA 2006 field campaign. Preliminary results suggest a relationship between increased aerosol concentrations and higher amounts of cloud ice water content and cloud-sized particle concentrations.
DE: 3311 Clouds and aerosols
DE: 3354 Precipitation (1854)
DE: 3374 Tropical meteorology
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly