RDMA Size distributions measured aboard the C-130 during ACE-1    

These are dry (RH 3-25) particle size distributions measured  with Radial Differential
Mobility Analyzer(RDMA). Particle size range is from 0.01 to 0.284um. The number
concentrations are in dN/dLogD with unit #/cc at ambient temperature and pressure. The
ambient temperature and pressure for every size distribution are put in the files. To get
integral values over the size range  these number must be multiplied by dLogD = 0.03125
and then summed. Particle losses at smaller sizes have been corrected based upon
laboratory studies for a similar sampling configuration. Largest corrections occurred
for regions of high ultrafine concentrations and result in generally better agreement
with total concentrations than previous uncorrected data. These corrected RDMA
concentrations can at times be higher or lower than total CN counts due to remaining
uncertainties in the flow and or small particle counting efficiencies of both RDMA and
CN counters at various altitudes.

In the files, data were aranged:
     column 1:  Julian day of 1995
     column 2:  hour; minute; second
     column 3:  time in hour in decimal
     column 4:  ambient temperature (K)
     column 5:  pressure (mb)
     column 6:  total channel number
     column 7-53: number concentration dN/dLogD (#/cc)

The accuracy of the time is about 15 second. Maximum channel number is 46 for
flight
14-15 and 41 for flight 16-32. Absent data are filled with -9999 in the files.
     
Questions concerning data should addressed to:
     Antony Clarke
     Department of Oceanography
     University of Hawaii
     1000 Pope Road, MSB 502B
     Honolulu, HI 96822
E-mail: Tclarke@soest.hawaii.edu or Jaimy@soest.hawaii.edu
Phone: 808-957-6215 or 808-956-7777.