The variable INP specifies the names of the two NCEP global data files
to be used in the interpolation. The first file should be for the snapshot
immediately preceeding the desired time, and the second file should be for
the snapshot immediately after the desired time. The input files should be
VICAR labelled, and in the JPL abridged format. This format is halfword data
in BSQ format, 181 lines by 360 samples. The number of channels varies with
the date of assimilation. The upper left corner is 90 degrees North, 0
degrees East/West. The attributes assigned to each channel are described on
the following pages.
Prior to October 1, 2000:
Channel Attribute Units Scaling Factor
1-16 Geopotential height meters 1.0
17-32 Temperature deg C 100.0
33-39 Relative Humidity percent 1.0
40 Surface Pressure millibars 10.0
41 Geopotential height at surface meters 1.0
42 Pressure reduced to MSL millibars 10.0
43 Pressure at tropopause millibars 10.0
44 Temperature at tropopause deg C 100.0
45 Precipitable water in column mm 10.0
46-61 Zonal Wind m/sec 100.0 (after 3/31/99)
62-77 Meridional Wind m/sec 100.0 (after 3/31/99)
October 1, 2000 and later:
Channel Attribute Units Factor
------- ---------------------------------------------------- ------ ------
1-26 geopotential height at 26 isobaric levels 1000-10 mb m 1.0
27-52 temperature at 26 isobaric levels 1000-10 mb deg C 100.0
53-78 zonal wind at 26 isobaric levels 1000-10 mb m/s 100.0
79-104 meridional wind at 26 isobaric levels 1000-10 mb m/s 100.0
105-125 relative humidity at 21 isobaric levels 1000-100 mb % 1.0
126 surface pressure mb 10.0
127 surface geopotential height m 1.0
128 surface temperature deg C 100.0
129 temperature at 2 meters above surface deg C 100.0
130 relative humidity at 2 meters above surface % 1.0
131 pressure at tropopause mb 10.0
132 geopotential height at tropopause m 1.0
133 temperature at tropopause deg C 100.0
134 precipitable water cm 1000.0
135 pressure reduced to MSL mb 10.0
136 Land / Sea Mask none 0/1
137 Ice Concentration none 0/1
138 Cloud Cover % 1.0
139 Snow Depth kg/m^2 1.0
140 geopotential height anomaly at 500 meters m 1.0
141 geopotential height anomaly at 1000 meters m 1.0
If the parameter TABLE is used, a table in the format appropriate for
use as input for or TIMSCAL2 (parameter RSTABLE in TIMSCAL2) is generated,
and stored with this file name.
The variable TIME specifies the time (in hours and fraction of hours
past midnight) for the desired interpolation. The time should be expressed
as GMT/UT, not as local time.
The variable LAT specifies the latitude (in degrees and fraction of
degrees North) for the desired interpolation. The range of valid values is
from -90.0 (South Pole) to +90.0 (North Pole).
The variable LONG specifies the longitude (in degrees and fraction of
degrees East longitude) for the desired interpolation. Note that all
locations in the Western Hemisphere have negative values. The valid range
of values is +/- 180.0
This optional parameter allows the user to supply a date to be placed in the output profile's header text. It is not used in the computation of the profile, and it is the responsibility of the user to assure that the date given is consistent with the input files.
This optional parameter allows the user to specify the desired surface elevation, in meters. This elevation will be used to compute the first layer in the interpolated profile. If ELEV is defaulted, then the elevation of the first layer will be the computed interpolated elevation that corresponds to the 1000 millibar level.
If a tablar output file is generated, relative humidities for
the upper layers and a top of atmosphere layer must be supplied from another
source. This parameter allows the user to specify any of the 6 MODTRAN model
atmospheres to complete the profiles. The meanings of the valid keywords are
as follows:
MLS - Midlatitude Summer
MLW - Midlatitude Winter
SAS - Subarctic Summer
SAW - Subarctic Winter
TROP - Tropical
USS - 1976 United States Standard Atmosphere
If this keyword is invoked, the 8 original profiles that are used to
compose the interpolated profile are also printed.