18
K. Kubiak-Wójcicka
a marked irregularity in the total outflow, which manifests as alternating cycles of
years of high outflows and then low. There were clear periods of high outflows in the
years 1977–1982, 1997–2002 and 2010–2011, while low outflows occurred in the
years 1988–1993 and 2003–2009. Since 2001, there has been an increased frequency
of alternating high and low outflows. In 2010, the outflow was exceptionally high,
totalling 86.9 km
3 , while in 2015 it was exceptionally low, at 40.8 km
3 .
Poland’s water resources include the country’s own indigenous resources from
precipitation within the country, and resources inflowing from outside Poland.
Indigenous resources constitute 87.5% of total resources. Poland’s resources from
outside the country constitute the remaining 12.5%. In terms of water management
and ability to control water resources, a high proportion of indigenous resources is
more favourable. The majority of total resources (95.5%) flows directly to the Baltic
Sea and the remaining part (4.5%) to neighbouring countries [6].
It is possible to determine whether available water resources can meet the needs
of the population and the economy by using a population-related measure. The per
capita total resources in the analysed multi-year period of 1951–2015 averaged
1,600 m
3 /person per year, while in the period 1975–2015 this value was slightly
higher, at approximately 1,700 m
3 /person. In this respect, Poland ranks 4th from last
among European countries. According to data from [1], only Malta, Cyprus, and
Czech Republic have lower per capita resources. The average per capita resources
in Europe are three times higher than in Poland. In the Baltic Sea countries such as
Latvia, Sweden, and Finland, per capita resources are even 10 times higher than in
Poland, totalling over 17,000 m
3 /person. In dry years, total resources for Poland are
even lower, totalling 1,100 m
3 /person (e.g., in 1990 and 2015), while in wet years the
values are higher, at 2,600 m
3 /person (1975) and 2,257 m
3 /person (2010). It should
be noted that in 1990–2015 there was a systematic increase in population in Poland,
which resulted in per capita water resources decreasing despite total outflow rates
being comparable to those of 1975–1989. Average water consumption in Poland in
the years 1999–2015 was around 300 m
3 /person/year [7].
Besides long-term variability in precipitation and outflow, Poland also experiences
seasonal and spatial variability.
2.2.1 Precipitation
Poland’s prevailing climate is temperate and transitional between a maritime and
continental climate. Annual average precipitation for Poland was calculated based
on annual sums of precipitation from 32 meteorological stations published by the
Central Statistical Office. The average annual precipitation in Poland for 1951–2015
was 625 mm, which is comparable with the average annual precipitation for 1975–
2015, which was 629 mm (Fig. 2.1). These values are among the lowest in Europe. The
spatial diversity of the annual precipitation sums that determine the size of Poland’s
resources is very large and ranges from around 500 mm to 1,100 mm. The lowest
precipitation is recorded in the Greater Poland region, where annual precipitation is
K. Kubiak-Wójcicka
a marked irregularity in the total outflow, which manifests as alternating cycles of
years of high outflows and then low. There were clear periods of high outflows in the
years 1977–1982, 1997–2002 and 2010–2011, while low outflows occurred in the
years 1988–1993 and 2003–2009. Since 2001, there has been an increased frequency
of alternating high and low outflows. In 2010, the outflow was exceptionally high,
totalling 86.9 km
3 , while in 2015 it was exceptionally low, at 40.8 km
3 .
Poland’s water resources include the country’s own indigenous resources from
precipitation within the country, and resources inflowing from outside Poland.
Indigenous resources constitute 87.5% of total resources. Poland’s resources from
outside the country constitute the remaining 12.5%. In terms of water management
and ability to control water resources, a high proportion of indigenous resources is
more favourable. The majority of total resources (95.5%) flows directly to the Baltic
Sea and the remaining part (4.5%) to neighbouring countries [6].
It is possible to determine whether available water resources can meet the needs
of the population and the economy by using a population-related measure. The per
capita total resources in the analysed multi-year period of 1951–2015 averaged
1,600 m
3 /person per year, while in the period 1975–2015 this value was slightly
higher, at approximately 1,700 m
3 /person. In this respect, Poland ranks 4th from last
among European countries. According to data from [1], only Malta, Cyprus, and
Czech Republic have lower per capita resources. The average per capita resources
in Europe are three times higher than in Poland. In the Baltic Sea countries such as
Latvia, Sweden, and Finland, per capita resources are even 10 times higher than in
Poland, totalling over 17,000 m
3 /person. In dry years, total resources for Poland are
even lower, totalling 1,100 m
3 /person (e.g., in 1990 and 2015), while in wet years the
values are higher, at 2,600 m
3 /person (1975) and 2,257 m
3 /person (2010). It should
be noted that in 1990–2015 there was a systematic increase in population in Poland,
which resulted in per capita water resources decreasing despite total outflow rates
being comparable to those of 1975–1989. Average water consumption in Poland in
the years 1999–2015 was around 300 m
3 /person/year [7].
Besides long-term variability in precipitation and outflow, Poland also experiences
seasonal and spatial variability.
2.2.1 Precipitation
Poland’s prevailing climate is temperate and transitional between a maritime and
continental climate. Annual average precipitation for Poland was calculated based
on annual sums of precipitation from 32 meteorological stations published by the
Central Statistical Office. The average annual precipitation in Poland for 1951–2015
was 625 mm, which is comparable with the average annual precipitation for 1975–
2015, which was 629 mm (Fig. 2.1). These values are among the lowest in Europe. The
spatial diversity of the annual precipitation sums that determine the size of Poland’s
resources is very large and ranges from around 500 mm to 1,100 mm. The lowest
precipitation is recorded in the Greater Poland region, where annual precipitation is