41 1010 DEMOTT, PAUL; KREIDENWEIS, SONIA; ROGERS, DAVID (dcrogers@ucar.edu) COLORADO STATE UNIVERSITY; (970)491-8257; pdemott@lamar.colostate.edu ICE NUCLEI CHEMICAL COMPOSITION FROM CFDC INSTRUMENT ON CITATION CRYSTAL-FACE MISSION 1 1 2002 07 29 2003 05 30 0 Midpoint of sampling interval in elapsed UT seconds from 0 hours on the day given by DATE 6 0.001 0.001 0.001 0.001 0.001 0.001 99999 99999 99999 99999 99999 99999 Salts; particle number fraction Metals, metal oxides, crustal dust; particle number fraction Carbonaceous; particle number fraction Sulfates; particle number fraction Mixed (insoluble with salt or sulfate); particle number fraction Other; particle number fraction 3 1.0 1.0 1.0 99999 99999 99999 Start Time; seconds Stop Time; seconds Sample type; 1=IN ambient, 2=IN from CVI cloud particle residuals 0 15 Ice nuclei composition was determined for selected samples collected by impacting ice crystals nucleated within the continuous flow diffusion chamber (CFDC) onto electron microscopy grids and analyzing the residual particles (from evaporation) by transmission electron microscopy with energy dispersive x-ray spectroscopy. Analyses are limited to particle diameters above about 50 nm. Two types of samples were collected, one of ambient aerosol particles processed directly as ice nuclei in the CFDC and the other of processed residual nuclei from cirrus anvil ice crystals collected by the Twohy group's counterflow virtual impactor (CVI). Salts include sodium and potassium salts. No attemptis made in this report to differentiate metal, metal oxide and crustal dust particles, so they are gathered in one category. Carbonaceous particles may be soot or organic species. Mixed particles were crustal dust, oxide or carbon particles that also included sulfate or salts. Other particles did not fit neatly into any particular category or were unidentified. Please contact the lead investigator for more detailed information. 67200 66700 67700 2 353 294 274 0 59 20