Title: C130 DMA Measurements

Contact:

   Antony Clarke
   Department of Oceanography
   University of Hawaii
   1000 Pope Road, MSB 502B
   Honolulu, HI 96822
   Phone: 808-957-6215 or 808-956-7777
   Fax: 808-956-7112
   E-Mail Address:
     tclarke@soest.hawaii.edu
   or
     jaimy@soest.hawaii.edu


Data Set Description:

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.

Format:

In the files, data were arranged:
column 1:  Date(UTC) YYYY/MM/DD
column 2:  Time(UTC) HH:MM:SS
column 3:  Lat (deg N)
column 4:  Lon (deg E)
column 5:  Ht (m)
column 6:  time in hour in decimal
column 7:  ambient temperature (K)
column 8:  pressure (mb)
column 9:  total channel number
column 10-56: number concentration dN/dLogD (#/cc)

The accuracy of the time is about 15 seconds.
Maximum channel number is 46 for flight 14-15
and 41 for flight 16-32.

Absent data are filled with -9999 in the files.

File Name Conventions:
   fxxdma.dat where xx is the flight number.
   An example for flight 14 is f14dma.dat.

References: None.