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microwave emissions are changed with the
fire-ripening growth for the layers of
combustible timbers. Speci
cally, such a dependence can be represented in the
following form (Yakimov 1996):
T
j
¼
jðk;
w
Þ
T
S
ð
1
exp
faðk;
w
Þ
h
gÞ þ
T
jS
exp
faðk;
w
Þ
h
g;
where
cient, respectively; w is the water
content in the timber, h is the thickness of emitting layer, T
S
is the soil temperature,
T
jS
is the soil brightness temperature. The following deciding factor, based on the
calculating the
κ
and
ʱ
are emission and absorption coef
) moment for the set of T
j
cor-
responding to the forest territory and registered on the wavelength
rst-order (M) and second-order (
˃
ʻ
= 2.25 cm were
proposed by Yakimov (1996). The value M (mean) is compared with the threshold
equaled to d = 7.251
d then forest plot has average or higher
fire-dangerous. If M < d then fire-dangerous of given forest plot is low. This
deciding rule is to be extended by the forest
˃
+ 249.876. If M
≥
fire model. An example of such a
model is one describing forest
fire as a running wave or as self-supporting process
of local energy release into the active environment.
The millimeter range (1
300 GHz bands) is best for land cover
diagnosis. As numerous experimental investigations show, addicting millimeter
range channels to the monitoring system enhances the accuracy of soil-plant for-
mations classi
30 mm and 30
-
-
cation by separating out roughnesses and small formations. It is
especially important for anthropogenic landscape monitoring.
McCloy and Lucht (2004) developed a method for comparing the complex
spatio-temporal patterns present in two long-time series of data of the seasonal
cycles of vegetation for a large part of the global land surface. It is based on the
use of two datasets derived from global satellite observations (AVHRR) and
Lund-Potsdam-Jena dynamic global vegetation model (LPJ-DGVM). McCloy and
Lucht (2004) showed that the LPJ model generally corresponds well with natural
vegetation whereas the former is primarily dependent on climate. Due to a lack of
representation of agriculture in the model, the correspondence with actual vegeta-
tive status was poor.
2.5 Microwave Monitoring of the Soil Moisture
2.5.1 Introduction
A series of world wide large scale Soil Moisture Experiments (SMEX) have been
conducted from 1997 to 2005 by the National Aeronautics and Space Adminis-
tration (NASA) and the United States Department of Agriculture (USDA),
Hydrology and Remote Sensing Laboratory, with the involvement of institutions in
the USA, Japan and Brazil (Jackson et al. 2002). The primary objective of those
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