cloudprod - generate cloud image products

cloudprod, cloudprod2 - Generate cloud image products

SYNOPSIS

cloudprod  [ parameter=value ]  [ inputfile outputfile ]
cloudprod  [ parameter=value ]  [ inputfile ... directory ]

cloudprod2  [ parameter=value ]  [ inputfile outputfile ]
cloudprod2  [ parameter=value ]  [ inputfile ... directory ]

Parameters are: variables, cloud_threshold, cloudfile_name, cloudmask_name, climatology, temprof_set, geoprof_set, temprof_var, geoprof_var, pressprof_var, cloud_top, cloud_pressure, cloud_temp, cloud_level, cloud_ppt, mask_level_top, cloud_ref, vapor_height, vapor_pressure, pressure_levels, feet_units, sounder_data, ppt_varname, cirrus_clouds,
cloudprod2: vis_varname, ir1_varname, wv_varname, ir2_varname.

DESCRIPTION

cloudprod, cloudprod2 generates cloud image products for a variety of satellites/imaging sensors. cloudprod2 differs from cloudprod in that cloudprod2 permits data from any sensor via explicit specification of input variable names, whereas cloudprod assumes variable names implicitly based on the the data origin, i.e. the originating sensor.

Input datasets have the following requirements:

Input data must be AVHRR, GMS, GVAR, or METEOSAT (cloudprod only; cloudprod2 overrides this restriction).
IR Channel for brightness temperatures is required.
A cloud mask variable, specified with parameter cloudmask_name, of type byte, which highlights/selects cloudy pixels in the input image, is recommended unless the cloud temperature threshold method, as provided with the optional parameter cloud_threshold, is an acceptable alternative. For any given pixel, values in variable cloudmask_name should be zero if a pixel is clear, and non-zero if a pixel is cloudy. A cloud-mask variable can be generated with avcloud (AVHRR) or other cloud-masking procedures.

cloudprod, cloudprod2 output variables are:

cloud_top:
A variable containing cloud-top altitudes (m or feet), with upper-level/cirrus temperatureadjustments applied (see cirrus_clouds).

cloud_pressure:
A variable containing cloud-top pressures (mbar).

cloud_temp:
A variable containing cloud-top temperatures (input temp. units).

cloud_level:
A variable specifying cloud-types according to altitude levels, as defined by pressure_levels.

wv_height: A variable with estimated heights for associated water-vapor channel data (m or feet).

wv_pressure:
A variable with estimated pressures for associated water-vapor channel data (mbar).
The water-vapor height/pressure method is outlined in Stewart, et al.

cloud_topx:
Variables containing masked cloud-top altitudes for cloud level x (m or feet).

cloud_ppt:
A variable containing cloud precipitable water content (AVHRR only) (mm).

clear_ppt:
A variable containing clear precipitable water content (GMS only) (mm).

cloud_reff:
A variable containing cloud effective radius values (mean particle size, microns) (AVHRR or GVAR only). cloud_reff provides microphysical property information for clouds, based on an algorithm developed by Rosenfeld and Gutmann.

cloudprod, cloudprod2 output datasets contain any combination of variables cloud_top, cloud_pressure, cloud_temp, cloud_level, cloud_topx, clear_ppt or cloud_ppt, cloud_reff, wv_height, wv_pressure.

cloud_top, cloud_pressure, cloud_temp, wv_height, and wv_pressure are calculated from geopotential height profiles, as provided by a global climatology (such as the NCEP/NCAR Reanalysis-derived climatology provided with TeraScan, on a 73x144 global grid) or a forecast model, which relate altitude, pressure and temperature monthly mean values on a global grid. (The NCEP/NCAR Reanalysis-derived global climatology is provided by datasets $REFDATA/climate/geopclim.tdf and $REFDATA/climate/tempclim.tdf.)

A cloud_level type is determined based on cloud-top pressure thresholds for several levels of clouds, specified with parameter pressure_levels. Cloud-type values are cloud_level=0 below lowest pressure_levels value, cloud_level=1 between lowest and second lowest pressure_levels, etc.

wv_height, wv_pressure are derived similarly to cloud_top, cloud_pressure, within the valid altitude range of the water-vapor channel weighting function, as per Stewart, et al.

PARAMETERS

variables: OPTIONAL. Parameter to specify input file variable names. The variables must be entered in ascending sequence (ch1-->chn). Defaults are:;           AVHRR: variables="avhrr_ch1 avhrr_ch2 avhrr_ch3 avhrr_ch4 avhrr_ch5"
          GVAR: variables="gvar_ch1 gvar_ch2 gvar_ch3 gvar_ch4 gvar_ch5"
          GMS: variables="svissr_vis svissr_ir1 svissr_ir2 svissr_ir3"
          METEOSAT: variables="mvissr_vis mvissr_wv mvissr_ir"
vis_varname: cloudprod2 only. Specifies the visible input variable name. Specification of a variable name overrides all implicit variable names assumed for the sensor type, if defined. The default is vis_varname="".
ir1_varname: cloudprod2 only. Specifies the IR brightness temperature input variable name. Specification of a variable name overrides all implicit variable names assumed for the sensor type, if defined. When explicitly specifying input variables (explicit specification is optional), an IR input variable name must be specified as well, with either ir1_varname or ir2_varname. The default is ir1_varname="".
wv_varname: cloudprod2 only. Specifies the water vapor brightness temperature input variable name. Specification of a variable name overrides all implicit variable names assumed for the sensor type, if defined. The default is wv_varname="".
ir2_varname: cloudprod2 only. Specifies an alternate brightness temperature (e.g., split window channel 2) input variable name. Specification of a variable name overrides all implicit variable names assumed for the sensor type, if defined. When explicitly specifying input variables (explicit specification is optional), an IR input variable name must be specified as well, with either ir1_varname or ir2_varname. The default is ir2_varname="".
climatology: Parameter to enable using climatology profiles for cloud top height determination. The default climatology dataset (provided by TeraScan in $REFDATA/climate/geopclim.tdf, tempclim.tdf) contains 12 months of monthly averaged profiles, derived from the NCEP/NCAR Reanalysis. The alternative is to use (a) time specific forecast model profile dataset(s). The default is climatology="yes".
temprof_set: Relevent only if climatology="no" (default) was specified. Parameter for specifying the name of the dataset containing model temperature profiles. The default is temprof_set="".
geoprof_set: Relevent only if climatology="no" (default) was specified. Parameter for specifying the name of the dataset containing model geopotential height profiles. The default is geoprof_set="".
temprof_var: Relevent only if climatology="no" (default) was specified. Parameter for specifying the name of the temperature variable in model temperature profiles. The default is temprof_var="".
geoprof_var: Relevent only if climatology="no" (default) was specified. Parameter for specifying the name of the geopotential height variable in model geopotential profiles. The default is geoprof_var="".
pressprof_var: Relevent only if climatology="no" (default) was specified. Parameter for specifying the name of the pressure level variable in model profiles. The default is geoprof_var="".
cloud_top: Parameter to enable/disable generation of cloud_top altitude output variable. cloud_top=y will generate variable cloud_top in output. The default is cloud_top=n.
cloud_pressure: Parameter to enable/disable generation of cloud_pressure altitude output variable. cloud_pressure=y will generate variable cloud_pressure in output. The default is cloud_pressure=n.
cloud_temp: Parameter to enable/disable generation of cloud_temp altitude output variable. cloud_temp=y will generate variable cloud_temp in output. The default is cloud_temp=n.
cloud_level: Parameter to enable/disable generation of cloud_level altitude output variable. cloud_level=y will generate variable cloud_level in output. The default is cloud_level=n.
mask_level_top: If cloud_level=y, mask_level_top enables/disables generation of (masked) cloud_topx output variables. Five such output variables can be generated, one for each cloud level (level=x=0,1,2,3,4). These variables contain cloud top altitudes per each cloud level, and are useful for generating cloud motion vectors specific to a single cloud level. mask_level_top=y will generate variables cloud_topx in the output dataset. The default is mask_level_top=n.
cloud_ppt: AVHRR or GMS only. Parameter to enable/disable generation of cloud_ppt altitude output variable.cloud_ppt=y will generate variable cloud_ppt in output. The default is cloud_ppt=n.
cloud_reff: AVHRR or GVAR only. Parameter to enable/disable generation of cloud_reff effective radius variable. Setting cloud_reff to yes will generate variable cloud_reff in output. The default cloud_reff setting is no.
vapor_height: OPTIONAL. Parameter to enable/disable generation of wv_height water-vapor altitude output variable. Requires input water-vapor channel. The default is vapor_height=n.
vapor_pressure: OPTIONAL. Parameter to enable/disable generation of wv_pressure water-vapor pressure output variable. Requires input water-vapor channel. The default is vapor_pressure=n.
cirrus_clouds: OPTIONAL. Parameter to disable/enable application of IR temperature adjustments to upper-level cirrus cloud temperatures, utilizing IR and WV scatter-plot regressions. Requires input water-vapor channel. Use cloud_threshold to vary the maximum cloud-top temperatures to be considered for adjustment. The default is cirrus_clouds=yes.
pressure_levels: When cloud_level=y, pressure_levels specifies the atmospheric pressures which delimit cloud-levels. Pressure is specified in millibars. The default is pressure_levels=[400, 500, 600, 700].
sounder_data: When input data is AVHRR and cloud_ppt=y, a filename containing precipitable water data derived from TOVS soundings is required. This sounding data is then interpolated over the cloudy pixels to generate an estimated map of precipitable water for clouds. There is no default.
ppt_varname: When input data is AVHRR and cloud_ppt=y, a variable in the file specified by sounder_data containing precipitable water data as measured by atmospheric sounding is required, and specified by name with ppt_varname. The default is ppt_varname=precip_water.
cloud_threshold: OPTIONAL. Parameter to specify a maximum cloud temperature (celsius) for selecting cloudy pixels, as an alternative to providing an input cloud-mask. Also specifies maximum temperature threshold for applied temperature adjustments (cirrus_cloud=yes). The default is cloud_threshold=-10.
cloudfile_name: cloudfile_name specifies an input cloudmask dataset name. If no dataset is specified, cloudprod looks for the cloudmask variable specified by cloudmask_name in the input image dataset. The default is cloudfile_name="".
cloudmask_name: cloudmask_name specifies the input cloudmask variable name. A cloud mask variable is required to generate cloud products. The default is cloudmask_name=cloud.
feet_units: OPTIONAL. Parameter to enable feet output units, for cloud/vapor altitude products. The alternative units are meters. The default setting is feet_units="no".

EXAMPLES

The first example demonstrates using cloudprod, with selection of five out of the possible seven output product categories.

     % cloudprod

     in/out files   : char(255) ? ../../meteoprod/img.1998092106.cal.reg ./img.1998092106.cal.reg.cloudprod

     cloudfile_name : char(255) ? [] ../../meteoprod/img.1998092106.cloudmask.reg

     cloudmask_name : char(255) ? [cloud]

     climatology    : char(  3) ? [yes]

     temprof_set    : char(255) ? []  ../../meteoprod/tempmodel.1998092106

     geoprof_set    : char(255) ? [] ../../meteoprod/geopmodel.1998092106

     temprof_var    : char(255) ? [] temperature

     geoprof_var    : char(255) ? [] geop_height

     pressprof_var  : char(255) ? [] pressure

     cloud_top      : char(  3) ? [no] y

     cloud_pressure : char(  3) ? [no] y

     cloud_temp     : char(  3) ? [no] y

     cloud_level    : char(  3) ? [no] y

     cloud_ppt      : char(  3) ? [no] n

     cloud_reff     : char(  3) ? [no] n

     mask_level_top  : char(  3) ? [no] y

     pressure_levels   : int (100) ? [400 500 600 700] 300 400 450 500 550 600 650 700 800 900

     Generating cloudproducts for ../../meteoprod/img.1998092106.cal.reg

       processing line 50...

       processing line 100...

       processing line 150...

       processing line 200...

       processing line 250...

       processing line 300...

       processing line 350...

       processing line 400...

       processing line 450...

       processing line 500...

       processing line 550...

./img.1998092106.cal.reg.cloudprod: Completed

     % contents ./img.1998092106.cal.reg.cloudprod

     printout       : char(  3) ? [no]

     Contents of File: ./img.1998092106.cal.reg.cloudprod    Page 1

     Dimension         Size    Coord         Scale      Offset    Variable

      prodYdim           586    y                1           0

      prodXdim           800    x                1           0

     Attribute       Type            Units           Value

      projection      long                            2

      et_affine       double                          -0.175462 0 0 0.175462 293.5 400.5

      satellite       string12                        gms-5

      sensor          long            std_sensor      svissr

      pass_date       long            std_date        1998/09/21

      start_time      double          std_time        05:31:00

      time_adjust     double          std_time        00:00:00

      attitude        double          radians         0 0 0

      sensor_tilt     double          radians         0

      scan_samples    long                            2291

      scan_rates      double                          1.65342 74205.2 0

      miss_algn_mat   double                          0.999999 0.000241148 0.00102046 -0.000242566 0.999999 0.00139035 -0.00102012

                                                       -0.00139059 0.999999

      use_orbele      long            boolean         0

      step_line_ang   double          radians         0.00014

      step_samp_ang   double          radians         0.00014

      center_line     double                          1384

      center_samp     double                          1146

      interp_points   long                            8

      scan_time       double          seconds         -59.9996 240 540 840 1140 1440 1740 2040

      x_pos           double          meters          -3.13906e+07 -3.07672e+07 -3.01291e+07 -2.94766e+07 -2.88101e+07 -2.81297e+07

                                                       -2.74359e+07 -2.67289e+07

      y_pos           double          meters          -2.81568e+07 -2.88366e+07 -2.95025e+07 -3.01544e+07 -3.07918e+07 -3.14145e+07

                                                       -3.20222e+07 -3.26145e+07

      z_pos           double          meters          -50226.4 -56610 -62966.6 -69292.9 -75586.1 -81843.1 -88060.9 -94236.5

      x_head          double                          -0.00191429 -0.00191429 -0.0019143 -0.00191431 -0.00191432 -0.00191432

                                                       -0.00191433 -0.00191434

      y_head          double                          0.00670305 0.00670287 0.00670269 0.00670251 0.00670233 0.00670215 0.00670197

                                                       0.00670179

      z_head          double                          -0.999976 -0.999976 -0.999976 -0.999976 -0.999976 -0.999976 -0.999976

                                                       -0.999976

      sensor_tilt_arr double          radians         -1.56894 -1.56895 -1.56897 -1.56898 -1.569 -1.56902 -1.56904 -1.56906

      sensor_twist    double          radians         3.14159 3.14159 3.14159 3.14159 3.14159 3.14159 3.14159 3.14159

      satellite_roll  double          radians         0 0 0 0 0 0 0 0

      satellite_pitch double          radians         0 0 0 0 0 0 0 0

      satellite_yaw   double          radians         0 0 0 0 0 0 0 0

      nutation_mat    double                          0.99993 0.99993 0.99993 0.99993 0.99993 0.99993 0.99993 0.99993 -0.0108508

                                                       -0.0108508 -0.0108508 -0.0108508 -0.0108508 -0.0108508 -0.0108508 -0.0108508

                                                       -0.00471655 -0.00471655 -0.00471655 -0.00471655 -0.00471655 -0.00471655

                                                       -0.00471655 -0.00471655 0.010851 0.010851 0.010851 0.010851 0.010851 0.010851

                                                       0.010851 0.010851 0.999941 0.999941 0.999941 0.999941 0.999941 0.999941

                                                       0.999941 0.999941 1.00139e-05 1.00138e-05 1.00137e-05 1.00137e-05 1.00136e-05

                                                       1.00135e-05 1.00134e-05 1.00134e-05 0.00471617 0.00471617 0.00471617

                                                       0.00471617 0.00471617 0.00471617 0.00471617 0.00471617 -6.11926e-05

                                                       -6.11925e-05 -6.11924e-05 -6.11923e-05 -6.11923e-05 -6.11922e-05 -6.11921e-05

                                                       -6.11921e-05 0.999989 0.999989 0.999989 0.999989 0.999989 0.999989 0.999989

                                                       0.999989

      center_lat      double          std_latitude    35  0.00 N

      center_lon      double          std_longitude   125  0.00 E

      map_angle       double          radians         0

      proj_param      double          std_latitude     0  0.00 N

      equator_radius  double          km              6378.14

      flattening      double                          0.00335281

      pressure_levels long                            900 800 700 650 600 550 500 450 400 300

      projection_name string16                        rectangular

      history         byte

     Variable        Type            Units

      cloud_top       long            m

      cloud_top0      long            m

      cloud_top1      long            m

      cloud_top2      long            m

      cloud_top3      long            m

      cloud_top4      long            m

      cloud_top5      long            m

      cloud_top6      long            m

      cloud_top7      long            m

      cloud_top8      long            m

      cloud_top9      long            m

      cloud_top10     long            m

      cloud_pressure  long            mb

      cloud_temp      long            celsius

      cloud_level     long

     Variable        Dimension       Size

      cloud_top       prodYdim         586

      cloud_top       prodXdim         800

      cloud_top0      prodYdim         586

      cloud_top0      prodXdim         800

      cloud_top1      prodYdim         586

      cloud_top1      prodXdim         800

      cloud_top2      prodYdim         586

      cloud_top2      prodXdim         800

      cloud_top3      prodYdim         586

      cloud_top3      prodXdim         800

      cloud_top4      prodYdim         586

      cloud_top4      prodXdim         800

      cloud_top5      prodYdim         586

      cloud_top5      prodXdim         800

      cloud_top6      prodYdim         586

      cloud_top6      prodXdim         800

      cloud_top7      prodYdim         586

      cloud_top7      prodXdim         800

      cloud_top8      prodYdim         586

      cloud_top8      prodXdim         800

      cloud_top9      prodYdim         586

      cloud_top9      prodXdim         800

      cloud_top10     prodYdim         586

      cloud_top10     prodXdim         800

      cloud_pressure  prodYdim         586

      cloud_pressure  prodXdim         800

      cloud_temp      prodYdim         586

      cloud_temp      prodXdim         800

      cloud_level     prodYdim         586

      cloud_level     prodXdim         800

     Variable            BadValue    ValidMin    ValidMax       Scale      Offset

      cloud_top       -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top0      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top1      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top2      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top3      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top4      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top5      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top6      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top7      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top8      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top9      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_top10     -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_pressure  -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_temp      -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

      cloud_level     -2.1475e+09 -2.1475e+09  2.1475e+09           1           0

The second example demonstrates using cloudprod2, with specification of the alternate split window IR channel avhrr_ch5
for brightness temperature inputs.

% cloudprod2

in/out files   : char(255) ?  testdata0   testdata0.cloudprod

vis_varname    : char(255) ? []

ir1_varname    : char(255) ? []

wv_varname     : char(255) ? []

ir2_varname    : char(255) ? [] avhrr_ch5

cloudfile_name : char(255) ? []

cloudmask_name : char(255) ? [cloud]

climatology    : char(  3) ? [yes]

cloud_top      : char(  3) ? [no] y

cloud_pressure : char(  3) ? [no] y

cloud_temp     : char(  3) ? [no] y

cloud_level    : char(  3) ? [no] y

cloud_ppt      : char(  3) ? [no]

cloud_reff     : char(  3) ? [no]

mask_level_top : char(  3) ? [no]

pressure_levels: int (100) ? [400 500 600 700]

testdata0: Using IR2 channel for cloudtop temperatures

Generating cloudproducts for testdata0

  processing line 50...

  processing line 100...

  processing line 150...

  processing line 200...

  processing line 250...

  processing line 300...

  processing line 350...

  processing line 400...

  processing line 450...

testdata0.cloudprod: Completed

REFERENCES

NCAR website: http://dss.ucar.edu/pub/reanalysis
Bull. Am. Met. Soc. 1996, (77) 437-471, "NCEP/NCAR 40 year Reanalysis Project," Kolmay et. al.

Rosenfeld D. and Gutmann G., 1994, Retrieving microphysical properties near the tops of potential rain clouds by multispectral analysis of AVHRR data, J. Atmos. Res., 34, 259-283.

Stewart,T.R., C.M.Hayden, W.L.Smith, 1985, A Note on Water-vapor Wind Tracking Using VAS Data on McIdas, Bull. Am. Meteor. Soc., 66, 1111-1115.

cloud_top:	A variable containing cloud-top altitudes (m or feet), with upper-level/cirrus temperatureadjustments applied (see cirrus_clouds).
cloud_pressure:	A variable containing cloud-top pressures (mbar).
cloud_temp:	A variable containing cloud-top temperatures (input temp. units).
cloud_level:	A variable specifying cloud-types according to altitude levels, as defined by pressure_levels.
wv_height:	A variable with estimated heights for associated water-vapor channel data (m or feet).
wv_pressure:	A variable with estimated pressures for associated water-vapor channel data (mbar). The water-vapor height/pressure method is outlined in Stewart, et al.
cloud_topx:	Variables containing masked cloud-top altitudes for cloud level x (m or feet).
cloud_ppt:	A variable containing cloud precipitable water content (AVHRR only) (mm).
clear_ppt:	A variable containing clear precipitable water content (GMS only) (mm).
cloud_reff:	A variable containing cloud effective radius values (mean particle size, microns) (AVHRR or GVAR only). cloud_reff provides microphysical property information for clouds, based on an algorithm developed by Rosenfeld and Gutmann.

cloudprod, cloudprod2 - Generate cloud image products

SYNOPSIS

DESCRIPTION

PARAMETERS

REFERENCES

SEE ALSO