Māris kļaviņŠ, azamat azizov, JĀnis zaļoksnis environment, pollution, development: the case of uzbekistan

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Table 3.1. 
Water resources on the Earth 
Types of water
Volume, km
3
The World Ocean
1 338 000 000
Groundwaters
23 900 000
incl. freshwaters 
10 530 000
Moisture in the soil
16 500
Glaciers, icecaps, permanent snow
24 064 100
Freshwater lakes
91 000
Saline lakes
85 400
Rivers
2120
Water in the atmosphere
12 900
Water in the atmosphere
Ocean surface
Rivers
Evaporation
Surface 
runoff
Freshwater
storage
Evapotranspiration
Condensation
Infiltration
Groundwater
runoff 
Precipitation
Water storage
in the oceans and seas
Water storage
in snow and ice
The  hydrological  cycle  (Figure 3.2)  represents  the  movement 
of water on the Earth. Five main sources of water are involved in 
the hydro logical cycle: water in the World Ocean, the atmo sphere, 
glaciers and icecaps, underground and freshwater sources. The 
hydrological cycle describes the relations among these main sources 
of water and shows the vital role of the processes of atmo spheric 
evaporation and precipitation fallout for the planet’s water balance. 
The Sun is the main source of energy, driving the global hydrological 
cycle as it warms the water masses on the Earth’s surface, making 
them evaporate or sublimate: not only from the surfaces of seas 
and oceans but also from the soil, glaciers, icecaps and the Earth’s 
snow cover. This water evaporates into the atmo sphere, where 
the vapour cools down and condensates. The dust particles in the 
atmo sphere become the condensation centres for water vapours.