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449. Three bands were chosen for the March 1995 imageries, the red band TM3 designed to
sense cholorophull absorption and hence vegetation discrimination and soil boundary
delineation (Jensen 1986), the near infrared (NIR) band 4 for delineation of the demarcation
between water bodies and adjacent dryland areas (Mulders and Epema, 1986; Lillesand and
Kiefer, 1987), and the mid infra red (MIR) band (5) useful for discriminating between
different soil zones in terms of relative soil moisture.
450. For the period June 1996 Thematic mapper (TM) bands 1 to 7 were available. In addition
to TM3, TM4 and TM5, (the uses of which are stated above), the blue band (1) is used to
sense water depth, the green band (2) is used to determine vegetation types, the thermal
infrared (TIR) band (6) is used to discriminate between land and water bodies, which have a
markedly thermal emittance, and the mid-infrared (MIR) band (7) is used in a similar way to
TM5 to discriminate between different soil zones, particularly in terms of relative soil
moisture. A number of single band and composite products were derived from the March
1995 and June 1996 data.
I. TM3 Single Band Black and White Image
451. The TM3 band, the chlorophyll absorption band, shows the water features very clearly
depicting areas of high soil moisture and standing water in the floodplain. In the March 1995
image (Figure 18, para. 82 of Professor Sefe's Second Opinion) the northern channel appears
to be much wider and carrying more flow of the Chobe system than the subsidiary channel to
the south, which shows a tenuous and meandering channel pattern.
452. The June 1996 image (Figure 22, para. 88 of Professor Sefe's Second Opinion) depicts
less extensive areas of high soil moisture and standing water on the floodplain but shows in
similar manner to the March 1995 image the greater width of the northern channel carrying
more flow and the tenuous meandering pattern of the southern channel.
II. The TM4 Single Band Black and White Image
453. Similarly, in both the March 1995 (Figure 19, para. 83 of Professor Sefe's Second
Opinion) and the June 1996 (Figure 23, para. 89 of Professor Sefe's Second Opinion) images,
the same characteristics differentiating the deeper fuller northern channel from the
meandering southern channel are depicted in the TM4 infrared reflectance band which shows
the delineation of land/water feature contrasts minimising areas of high soil moisture because
of vegetative growth on the floodplain and the Island.
III. False Colour Composite Image
454. False colour composites made up to TM 3, TM 4 and TM 5 in relation to the March 1995
data (Figure 20, paras. 84 and 90) and of TM 7, TM 4 and TM 1 in respect of the June 1996
data (Figure 24) are also shown and analysed in Professor Sefe's Second Opinion. Both
composites of 1995 and 1996 show water bodies dark black (due to their high radiative
absorpbance in all the depicted wavebands), and the northern channel of the Chobe River
appears wider and therefore is likely deeper than the more southerly channel, even in June
when there is some back flow in the system due to high flow in the Zambezi.
IV. The Classified Image Thematic Map