geoph [ inputfile ... ] There are no parameters.
geoph derives geophysical parameters from SSM/I TeraScan datasets. The named input files must be SSM/I TeraScan datasets output from the DMSP ingest functions rtdin and rdsin. Thus, the input filenames must have the suffix ".mi_s", meaning SSM/I sensor dataset. Output filenames are generated to have the same form as the input filenames, except with the suffix ".mi_g", meaning SSM/I geophysical dataset. The output datasets contain 9 two-dimensional variables with the same spatial resolution as the 19-37Ghz channels of the SSM/I input data. These variables, their units and their corresponding algorithms are listed below:
Geophysical Variables:
Total Columnar Water Vapor Alishouse, et al., 1990, IEEE Trans. Geo. Rem. Sens., V28, No. 5, pg. 811. Units are kg/m2 or precipitable millimeters.
Total Columnar Liquid Water Alishouse, et al., 1990, IEEE Trans. Geo. Rem. Sens., V28, No. 5, pg. 817. Units are kg/m2 or precipitable millimeters.
Rain Rate Wentz, F., 1987: JGR, V91, C2, pg. 2289. This is computed linearly from liquid water, therefore the spatial structure of the fields is identical. Units are mm/hr.
Wind Speed Goodberlet, M. A. and C. T. Swift, 1992, IEEE Trans. Geo. Rem. Sens., V30, No.5., pg. 1076. Units are m/s.
Rain Flag Goodberlet, M. A. and C. T. Swift, 1992, IEEE Trans. Geo. Rem. Sens., V30, No.5., pg. 1076. Rainflag is computed as a part of the wind speed algorithm to identify regions where atmospheric conditions (generally rain) is contaminating the wind speed retrievals. Values range between 0 and 3, with 0 indicating no contamination, and 3 indicating the greatest contamination.
Rain Flag Wind Speed Error (m/s) 0 < 2 1 2-5 2 5-10 3 > 10
Sea Ice Concentration Cavalieri, et al., 1991, Jour. Geoph. Res., V96, No. C12, pg. 21989.
Parameters are first-year, multi-year and total ice concentrations. The weather filter is implemented. Units are percentage.
Land surface type classification Neale, et al., 1990, IEEE Trans. Geo. Rem. Sens., V28, No. 5, pg. 829.
Values indicate the following surface types: STANDING WATER 0
DENSE VEGETATION 1
AGRICULURAL RANGE VEGETATION 2
ARABLE SOIL DRY 3
SOIL MOIST SURFACE 4
SEMI ARID SURFACE 5
DESERT 6
PRECIPITATION OVER VEGETATION 7
PRECIPITATION OVER SOIL 8
COMPOSITE VEGETATION & WATER 9
COMPOSITE WATER & SOIL 10
SNOW 11
UNKNOWN CLASS 13
This example shows: 1) the contents of the input SSM/I dataset, 2) the invocation of geoph, and 3) the contents of the output geophysical dataset.
% contents f11.92345.0129.mi_s
Contents of File: f11.92345.0129.mi_s Page 1
Dimension Size Coord Scale Offset
miline_hi 420 y 1 0
misamp_hi 128 x 1 0
miline_lo 210 y 2 0
misamp_lo 64 x 2 0
Attribute Type Units Value
projection long std_projection sensor_scan
et_affine double 1 0 0 1 0 0
satellite string12 f-11
sensor long std_sensor ssmi
pass_date long std_date 92/12/10
start_time double std_time 01:29:27.729
time_adjust double std_time 00:00:00
attitude double radians 0 0 0
sensor_tilt double radians 0
scan_samples long 128
scan_rates double 0.526667 236.967 3.30914
sensorient double radians -1.5708 -0.785398 0 0.890118
-0.890118
orb_elem_date long std_date 92/12/10
orb_elements double 0.421788 0.829381 0.00016
0.0012722 0.745781 0.722212
0.274848
history byte
Variable Type Units
mi_85v short kelvin
mi_85h short kelvin
mi_19v short kelvin
mi_19h short kelvin
mi_37v short kelvin
mi_37h short kelvin
mi_22v short kelvin
Variable Dimension Size
mi_85v miline_hi 420
mi_85v misamp_hi 128
mi_85h miline_hi 420
mi_85h misamp_hi 128
mi_19v miline_lo 210
mi_19v misamp_lo 64
mi_19h miline_lo 210
mi_19h misamp_lo 64
mi_37v miline_lo 210
mi_37v misamp_lo 64
mi_37h miline_lo 210
mi_37h misamp_lo 64
mi_22v miline_lo 210
mi_22v misamp_lo 64
Variable BadValue ValidMin ValidMax Scale Offset
mi_85v 0 -32768 32767 0.01 0
mi_85h 0 -32768 32767 0.01 0
mi_19v 0 -32768 32767 0.01 0
mi_19h 0 -32768 32767 0.01 0
mi_37v 0 -32768 32767 0.01 0
mi_37h 0 -32768 32767 0.01 0
mi_22v 0 -32768 32767 0.01 0
% geoph f11.92345.0129.mi_s
Processing: SSM/I Brightness Temperatures -> Geophysical Quantities
TDF data set f11.92345.0129.mi_g created.
% contents f11.92345.0129.mi_g
Contents of File: f11.92345.0129.mi_g Page 1
Dimension Size Coord Scale Offset
line 210 y 1 0
sample 64 x 1 0
Attribute Type Units Value
projection long std_projection sensor_scan
et_affine double 0.5 0 0 0.5 0.5 0.5
satellite string12 f-11
sensor long std_sensor ssmi
pass_date long std_date 92/12/10
start_time double std_time 01:29:27.729
time_adjust double std_time 00:00:00
attitude double radians 0 0 0
sensor_tilt double radians 0
scan_samples long 128
scan_rates double 0.526667 236.967 3.30914
sensorient double radians -1.5708 -0.785398 0 0.890118
-0.890118
orb_elem_date long std_date 92/12/10
orb_elements double 0.421788 0.829381 0.00016
0.0012722 0.745781 0.722212
0.274848
history byte
Variable Type Units
class float none
totvap float kg/m2
totliq float kg/m2
rain float mm/hr
wndspd float m/s
rainflg float mask
totice float %
firstice float %
multiice float %
Variable Dimension Size
class line 210
class sample 64
totvap line 210
totvap sample 64
totliq line 210
totliq sample 64
rain line 210
rain sample 64
wndspd line 210
wndspd sample 64
rainflg line 210
rainflg sample 64
totice line 210
totice sample 64
firstice line 210
firstice sample 64
multiice line 210
multiice sample 64
Variable BadValue ValidMin ValidMax Scale Offset
class -99999 -3.4028e+38 3.4028e+38 1 0
totvap -99999 -3.4028e+38 3.4028e+38 1 0
totliq -99999 -3.4028e+38 3.4028e+38 1 0
rain -99999 -3.4028e+38 3.4028e+38 1 0
wndspd -99999 -3.4028e+38 3.4028e+38 1 0
rainflg -99999 -3.4028e+38 3.4028e+38 1 0
totice -99999 -3.4028e+38 3.4028e+38 1 0
firstice -99999 -3.4028e+38 3.4028e+38 1 0
multiice -99999 -3.4028e+38 3.4028e+38 1 0
dmsp, ssmi, rtdin, rdsin, t1edr, t2edr, miedr.
In most cases the accuracy and general applicability of the algorithms listed above are found in documents referenced.
Last Update: $Date: 1998/05/29 17:19:08 $