86
ENVIRONMENT, POLLUTION, DEVELOPMENT: THE CASE OF UZBEKISTAN
Earth (Figure 5.12). Along with the increase in temperature, the
moisture concentration and hence rainfall will also increase.
Precipitation will not be regular, and there will be a risk of drought
periods in many regions of the Earth. Rainfall changes can affect the
Earth’s
processes, for example, heavy precipitation in polar regions
may affect the stability of glaciers and ocean currents.
The mean air temperature on the Earth is modelled for the
periods between 2020 and 2029 and between 2090 and 2099 vis-
à-vis the temperature in the period between 1980 and 1999,
depending on the potential society development
and climate change
scenarios: B1; A1B; A2 (from top to bottom). The figure shows how
the air temperature on the Earth can change depending on the
society development scenario.
Both rainfall changes and global warming affect the global sea
level. It hardly needs saying that, as the Earth’s temperature rises,
the ice sheets of
the polar region begin to melt, and it turns out
that the permafrost boundary is not permanent at all. This melting
causes the water level in oceans to rise. The climate change models
project that, until 2100, the water level in
seas and oceans will have
risen by 0.09 to 0.88 metres (Figure 5.13).
This figure shows the actual and possible changes in the water
level in seas and oceans in the period between 2000 and 2100.
The mean water temperature in the oceans and seas will also
increase, which means that the melting of glaciers and ice sheets
and the rise of the sea and ocean levels will continue for hundreds of
Figure 5.12.
Projected
rainfall changes
Mean changes in
(a)
precipitation
(mm day
–1
), (b) soil
moisture content (%),
(c) runoff (mm day
–1
)
and (d) evaporation
(mm day
–1
). Changes
are annual means for
the A1B
scenario for the
period 2080 to 2099
relative to 1980 to 1999.
Soil moisture and runoff
changes are shown
at land points with
valid
data from at least
10 models.
5. GLOBAL ENVIRONMENTAL PROBLEMS
87
years after the stabilisation of greenhouse gas concentrations. With
that, the inhabitable dry land areas will decrease. With the melting of
polar ice, large amounts of freshwater will flow into the oceans and
seas, affecting the marine fauna, ocean currents and thermal balance.
Estimation
Observations
Prognosis
500
400
300
200
100
0
-100
-200
1800
1850
1900
1950
2000
2050
2100
Sea level changes (mm)
It is worth noting that climate change cannot be projected
accurately because there is also a possibility that these processes
occur faster,
by leaps, causing global cataclysms.
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