Practical Work

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Practical Work Exercise 1 Plot the relation
between TB or Emissivity versus SM

Backscattering versus SM

Dielectric Constant versus SM Go to the directory
gt mtech_2004/srcs Run the program run the
program mdobsm_new.exe You will get prompt
Give output file for storing SM, Dielectric
constant, emissivity, TB and Sigma-0
tb_sigma0.out (you can give your own name) Give
No. of Soil Moisture values (for which you have
to calculate TB) 6 Give Polarization H or V
H Give bulk density, specific density, sand,
clay, SIGB(conductivity of soil paste), t(deg),
theta(deg) 1.47 2.66 51.5 35.1 1.07 27.0
23.0 Give SM Values in Gravimetric (in
percent) 2.5 5.0 10.0 15.0 25.0 30.0 Give
Frequency of the sensor (Radarsat) 5.3
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SM real img. Emis TB
sigma-0 .03625 4.07485 .49538
.86939 260.81810 -8.84035 .07250 5.51415
.82016 .81685 245.05580 -7.37199
.14500 8.83953 1.59869 .72741 218.22450
-5.64498 .21750 12.68962 2.53114
.65643 196.92800 -4.63981 .36250 21.75999
4.79145 .55241 165.72290 -3.49119
.43500 26.91065 6.09685 .51322 153.96650
-3.12669 Open the out file in Excel and see each
column First column Soil moisture in
fraction Second Column Dielectric constant
(real part) Third column Dielectric constant
(img. Part) Fourth Column Emissivity Fifth
Column TB Sixth Column Backscattering
Coefficient Using Generate plots SM versus E
SM versus TB SM versus dielectric, SM versus
Sigma-0 (backscattering coefficient)
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Tips 1) Right click Format chart In Color
panel white 2) Automatic select white (border
will be white 3) Right click Source data
Series Give proper name 4) Click on axis and
change options to remove x- and y-axis locations
and labels
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Exercise 2 ERDAS IMAGINE Learn first ERDAS
simple tasks Open ERS-1 SAR data over Manali
area Open JERS-2 SAR Data over Mumbai(IIT) Open
Radarsat-1 SAR data over Manali Open Radarsat-1
Fine mode data over Manali Convert DN values into
backscattering Coefficient (sigma-0)
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Exercise 2 AQUA AMSR- E (passive microwave
Data) Processing for TB, SM, T, and vegetation
water content) http//nsidc.org/data/amsr/ and
press Ordering AMSR-E data from NSIDC Look for
Aqua Daily surface soil moisture, interpretive
parameters, QC EASE Grids Click on Right side
Data Pool Look for TOP menu at the top of the
page Search the Data Pool and clikc on
that Look for AMSA and click on that Look for
AE_Land3.1 and click on that At the end you can
see Start Date 2004 Mach day 1
End Data 2004 March
day 31 (add selection) Time start and time end
00 23.00 (add selection)
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Now you can see Four corners to be selected
North
Latitude West Longitude
East Longitude
South Latitude
40
65
95
04 Add selection Next select day/night flag Next
press Get granules Now you can see .zip files or
.gz files, you can download The data may be 63 MB
(takes long time), do not download, using
existing one
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The files are in .HDF format (Hierarchical Data
format) in which data are stored in objects. You
can open the file using ENVI freelook or decode
using NASA free tools using the following
command dgthdp dumpsds -h -o output_file
input_file(I.e .hdf file) The output file
contains information about the input file Using
the following command, one can extract image file
such as soil moisture, TB, temperature,
Vegetation water content etc. Dgthdp dumpsds n
Variable_name (ex.Soil_Moisture) -o
output_file_name b input_file_name (.hdf file)