Title:  ACE-Asia Surface: Gosan(Kosan) Aerosol HTDMA Hygroscopic Growth
        Size Distribution (Brechtel) - PRELIMINARY

Instrument PI: 

     Fred Brechtel 
     Brechtel Mfg. Inc. 
     Hayward, CA 94544 USA  
     Tel (510) 732-9723 
     Fax (510) 732-9153  
     email: fredb@bnl.gov

1.0 DATA SET OVERVIEW:

     This dataset contains ACE Asia Humidified Tandem Differential 
     Mobility Analyzer (HTDMA) data files from BNL HTDMA deployed at 
     the Gosan surface site during ACE Asia April 9-April 27, 2001. 

     THESE ARE EXTREMELY PRELIMINARY DATA AND SHOULD NOT BE USED IN 
     ANY PUBLICATION UNTIL 'RELEASED' BY FRED BRECHTEL (fredb@bnl.gov).  
     NO SMEARING CORRECTIONS, RAPID-SCAN-RELATED MOBILITY SHIFTS, DMA 
     TRANSFER FUNCTION, DILUTION FACTOR OR OTHER HTDMA-RELATED 
     DECONVOLUTION PROCEDURES HAVE BEEN APPLIED TO THESE DATA - SO BE 
     WARNED!!!!!!

     Data were obtained by G. Buzorius and F. Brechtel under funding by 
     DOE ACP and NOAA OGP.

     Raw concentrations from the CPC sampling from the mono out of the 
     second DMA are reported. Although we don't expect significant shifts 
     in the size of these wet distributions to occur during future 
     processing, there may be unforseen changes.

     Due to technical difficulties, we are unable to report growth 
     factors prior to April 12th. There are very limited data during the 
     first week of April but it will take 'extra' processing in order to 
     assess the quality of data during this time.

2.0 DATA FORMAT:

     Data are reported in daily files, the date of the acquisition is 
     given in the filename. The columns of each row of data are as follows:

     Col 1 = Local Hour of Beginning of Measurement time (=UTC-9hr)

     Col 2 = Local Minute of Beginning of Measurement time

     Col 3 = Local Second of Beginning of Measurement time

     Col 4-23 = 60 sec Avg Relative Humidities (%) and standard deviations 
                of RH (%) for sheath, mono, excess and aerosol out flows of 
                second DMA during both UP and Down scans.

     Col 24 = Dry size (nm) of particle selected by DMA 1

     Col 25-84 = Wet particle diameters for up scan concentration data (nm)

     Col 85-144 = Wet number concentrations for up scan (cm^-3)

     Col 145-204 = Wet particle diameters for down scan concentration data (nm)

     Col 205-264 = Wet number concentrations for down scan (cm^-3)

3.0 DATA NOTES:     

     The following IDL print statement was used to print the data to file:

       printf,2,format='(24(e14.7,1x),120(e14.7,1x),120(e14.7,1x))',$hr,
       min,sec,rh1,rh1s,rh2,rh2s,rh3,rh3s,rh4,rh4s,rh5,rh5s,rh6,rh6s,rh7,
       rh7s,rh8,rh8s,rh9,rh9s,rh10,rh10s,$ ddry,dpup,Nup,dpdown,Ndown

     April 12th some data but format of file changed and looks like some 
     system tests performed with cal particles

     April 16th looks like calibration/system checks - or tests of low RH 
     exposure and subsequent drying

     April 17th looks like calibrations - concentrations are high and look 
     like atomizer output

     April 19th may be calibrations with Ammonium Sulfate and not ambient 
     data.

     April 20th looks ok - ambient measurements.

     April 21st looks to have some cal data for first few scans and then 
     ambient data.

     April 22nd looks to have a few cal scans and then ambient data - the 
     smaller the Ddry the narrower the apparent wet distribution looks.

     April 23rd appears to be ALL calibration data with some strange scans 
     where flow control/rh control may be poor - this day should be ignored 
     for now until it is verified that there are any ambient data included.

     April 24th looks very interesting with some high RH data and a broad 
     dry selected size range - almost exclusively monodisperse wet 
     distributions

     April 25th ambient data

     April 26th - some ambient data, file ends with some calibrations - note 
     high concentrations