Houston Air Pollution

1
CAMx 3.10 exercise
AQM Workshop 2002 Beata Czader
2
CAMx information
http//www.camx.com
Computer/Operating systems

• Dec alpha workstation
• Sun Ultra Sparcstation
• SGI workstation with complier flags to enable
  OMP
• IBM workstation
• HP/UX workstation
• IX86 PC running Linux
• Linux workstation with pgf77 compiler flags to
  enable OMP

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Installation

• download camx
• modify MakeFile
• compile

make platform DOMAINdomain_name make sun
DOMAINotag
executable ? CAMx.otag.sun

• download camx test case and additional software
• HOSTNAME ftp.environ.org
• USERNAME camx
• PASSWORD pass4camx

4
AVGDIF
Use to compare two UAM-IV format files (.avrg)
and print a table of differences.
Compile AVGDIF for the same binary format as is
used for CAMx f77 avgdif.f o avgdif.sun

• The input parameters for avgdif are
• name of input file 1
• name of input file 2
• output file name
• min and max layers to calculate differences for

5
AVGDIF result
avg difference for all hours NO avg
2.696E-09 in 63582 cellhrs NO2 avg
3.295E-09 in 82294 cellhrs O3
avg 4.846E-08 in 86097 cellhrs PAR
avg 8.184E-09 in 84316 cellhrs TOL
avg 5.585E-11 in 82685 cellhrs ETH
avg 7.285E-11 in 81766 cellhrs
OLE avg 1.784E-10 in 66588
cellhrs PAN avg 4.957E-10 in
86920 cellhrs ISOP avg 6.907E-10 in
64920 cellhrs XYL avg 3.996E-11 in
66903 cellhrs FORM avg 1.452E-09
in 84343 cellhrs ALD2 avg
5.685E-10 in 84379 cellhrs HNO3 avg
3.514E-09 in 86950 cellhrs NXOY
avg 8.086E-11 in 89031 cellhrs NTR
avg 2.321E-10 in 86835 cellhrs Number
of cellhrs compared 96768
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FINE2UAM
Use to convert fine grid output files (.favrg)
to coarse grid (.avrg) format.
Compile FINE2UAM using Makefile make

• The input parameters for avgdif are
• name of coarse grid file
• name of fine grid file
• output file name

7
CAMXPOST
Use to combine observations and predictions,
calculate statistics, plot time series.

• AVGCAT
• OBSCAT

preprocessing software, concatenates several
CAMx .avrg files together into a single file

• CAMXPOST

the central program to prepare files for
statistical evaluation

• generate a running n-hourly file in coarse grid
  avg format
• generate a maximum n-hourly file in coarse grid
  avg format
• pairs predictions and observations and generates
  an ASCII running n-hourly prediction
  observation file for further processing
• generates an ASCII file of maximum observations
  at each site

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CAMXPOST post processing

• CAMXSTAT

reads an n-hourly file generated by CAMXPOST and
calculates statistics

• unpaired (time and space) peak prediction
  accuracy
• space-paired, time-unpaired peak prediction
  accuracy by site
• space-paired, time-unpaired peak bias and error
  over all sites
• space-paired, time-paired peak bias and error
  over all sites
• mean prediction
• mean observation
• differences and normalized differences in mean
  prediction and mean observations
• absolute, normalized, and fractional bias
• absolute, normalized, and fractional error
• root mean square error

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CAMXPOST post processing

• EXTSTAT
• COMBINE2

pull important statistics from a series of report
files generated by CAMXSTAT in order to enable
graphical summaries

• TIME_SERIES.XLS

Excel macro that generates time-series and
scatter plots of data