4 Water Resources in Poland and Their Use
45
4.2 Water Resources in Selected European Countries
The abundance of water in a given area depends on the factors of the geographic
environment such as climate, geological structure, land relief, and land use. Water
resources of an area are particularly dependent on climatic conditions, shaped by
the amount of solar radiation, distance from seas and oceans, land relief, including
height above sea level, and course of mountain ranges. In reference to Europe, it
should be emphasised that it is located in only one climatic zone, and is surrounded
by seas having a warming effect on the continent. The mountains have latitudinal
distribution facilitating airflow of both marine and oceanic air.
Atmospheric precipitation and the related outflows are distributed over continents,
including Europe and therefore Poland, very unevenly. On the Earth, dry areas occupy
almost ¼ of the land surface, and a constant deficit of freshwater is recorded on more
than half of the surface area of continents.
The assessment of water resources considers the absolute amount of precipitation water is reaching the surface of a given country, the amount of outflow and
potentially inflow of water, as well as the amount of water per capita in a year. The
assessment of particular values is imprecise. The starting material comprised data
collected in materials of the Central Statistical Office [4], including absolute values
of atmospheric precipitation, evapotranspiration, own resources of the country, and
water inflow in selected countries. Based on hydrometeorological data and comparison of the surface area and size of the population, precipitation and outflow indices
were calculated, expressed in millimetres of the water layer, as well as annual water
resources per one resident.
Among the selected European countries, atmospheric alimentation somewhat
exceeding 1400 mm·year
−1 was determined in Switzerland and Slovenia. In Croatia,
Austria, UK, Norway, and Ireland, it is maintained at a level of 1000–1300 mm. In
Poland, Romania, Hungary, and several other countries (Fig. 4.1), it approximates
600–700 mm·year
−1 . In reference to the climatic conditions of the countries, and
particularly to high potential evaporation, the amount of outflow (own resources of a
country) is low, because it does not reach 200 mm. In countries with higher precipitation, the amount of outflowing water is maintained at a level of 600–1000 mm per
year.
The absolute amount of water resources is equivalent to the amount of mean
outflow from a given country. The outflowing water can originate from internal
resources, i.e. from atmospheric alimentation of the territory of the country, and
outflow from outside its borders. Discharge of transit rivers (having its springs in
another country) increases the water resources of the country, sometimes very radically. Figure 4.2 presents a comparison of water resources developing in the territory
of the country and total renewable resources, i.e. with water outflow from parts of
catchments located outside of the national borders. A particularly favourable situation concerns Slovakia, Bulgaria, Hungary, Netherlands, Serbia, and Croatia. Their
resources are small, and the rivers flowing through the territories carry high amounts
45
4.2 Water Resources in Selected European Countries
The abundance of water in a given area depends on the factors of the geographic
environment such as climate, geological structure, land relief, and land use. Water
resources of an area are particularly dependent on climatic conditions, shaped by
the amount of solar radiation, distance from seas and oceans, land relief, including
height above sea level, and course of mountain ranges. In reference to Europe, it
should be emphasised that it is located in only one climatic zone, and is surrounded
by seas having a warming effect on the continent. The mountains have latitudinal
distribution facilitating airflow of both marine and oceanic air.
Atmospheric precipitation and the related outflows are distributed over continents,
including Europe and therefore Poland, very unevenly. On the Earth, dry areas occupy
almost ¼ of the land surface, and a constant deficit of freshwater is recorded on more
than half of the surface area of continents.
The assessment of water resources considers the absolute amount of precipitation water is reaching the surface of a given country, the amount of outflow and
potentially inflow of water, as well as the amount of water per capita in a year. The
assessment of particular values is imprecise. The starting material comprised data
collected in materials of the Central Statistical Office [4], including absolute values
of atmospheric precipitation, evapotranspiration, own resources of the country, and
water inflow in selected countries. Based on hydrometeorological data and comparison of the surface area and size of the population, precipitation and outflow indices
were calculated, expressed in millimetres of the water layer, as well as annual water
resources per one resident.
Among the selected European countries, atmospheric alimentation somewhat
exceeding 1400 mm·year
−1 was determined in Switzerland and Slovenia. In Croatia,
Austria, UK, Norway, and Ireland, it is maintained at a level of 1000–1300 mm. In
Poland, Romania, Hungary, and several other countries (Fig. 4.1), it approximates
600–700 mm·year
−1 . In reference to the climatic conditions of the countries, and
particularly to high potential evaporation, the amount of outflow (own resources of a
country) is low, because it does not reach 200 mm. In countries with higher precipitation, the amount of outflowing water is maintained at a level of 600–1000 mm per
year.
The absolute amount of water resources is equivalent to the amount of mean
outflow from a given country. The outflowing water can originate from internal
resources, i.e. from atmospheric alimentation of the territory of the country, and
outflow from outside its borders. Discharge of transit rivers (having its springs in
another country) increases the water resources of the country, sometimes very radically. Figure 4.2 presents a comparison of water resources developing in the territory
of the country and total renewable resources, i.e. with water outflow from parts of
catchments located outside of the national borders. A particularly favourable situation concerns Slovakia, Bulgaria, Hungary, Netherlands, Serbia, and Croatia. Their
resources are small, and the rivers flowing through the territories carry high amounts