HR: 16:00h
AN: A14C-01 INVITED     [Abstracts]
TI: Trace Gases and Ice: What Conditions Lead to Substantial Uptake?
AU: * Abbatt, J
EM: jabbatt@chem.utoronto.ca
AF: University of Toronto, Department of Chemistry 80 St. George St., Toronto, ON M5S 3H6 Canada
AU: Ullerstam, M
EM: mullerst@chem.utoronto.ca
AF: University of Toronto, Department of Chemistry 80 St. George St., Toronto, ON M5S 3H6 Canada
AB: The non-reactive interactions of ice and atmospheric trace gases have been studied in sufficient detail in the past few years that the general conditions necessary for efficient uptake from the gas phase are becoming apparent. In particular, this talk will summarize the findings made for the interactions of semi-volatile organics, which strongly indicate that the volatility of the organic is the prime factor determining uptake. It will also focus on the uptake of acids, where it has been shown that strong acids, such as nitric acid and hydrogen chloride, are more efficiently adsorbed than weak acids, such as sulfur dioxide and acetic acid. In this context, new experimental results for the uptake of nitric acid at low partial pressures will be presented that are in considerably better agreement with field measurements in cirrus clouds than are measurements conducted at non-atmospheric partial pressures, and for the uptake of gases under conditions where the ice is growing.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0320 Cloud physics and chemistry
DE: 0340 Middle atmosphere--composition and chemistry
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting