5 European Semi-enclosed Seas
133
Table 5.1 Characteristics of the basins and straits. References: (1) Unluata et al. (1990), (2) Mariotti et al. (2002), (3) Struglia et al. (2004), (4) HELCOM (1986), (5) Simonov and Altman
(1991), Stanev and Peneva (2002), (6) Baschek et al. (2001), (7) Liljebladh and Stigebrandt (1996),
(8) Döös et al. (2004), Meier et al. (2006). More estimates can be found in Tsimplis et al. (2006)
Black Sea
Mediterranean Sea
Baltic Sea
Basin
characteristics
Area, km 2
436,400
2,500,000
415,000
Volume, km 3
547,000
3,700,000
21,700
Mean depth, m
1,253
1,500
55
Maximum depth, m 2,212
5,267
459
Surface water
Budget
(km 3 /yr)/
(mm/yr)
Precipitation
300/687 (1)
827–1192/331–477 (2)
224/540 (4)
Evaporation
350/802 (1)
2335–2940/934–1176 (2) 184/443 (4)
River inflow
350/802 (1)
250–500/100–200 (3)
436/1050 (4)
Strait
Width (narrowest
section, km)
Bosporus 0.7 Gibraltar 14
Øresund 4,
Great Belt 16
Outflow, km 3 /yr
600 (5)
25,544 (6)
946 (7)
Mean salinity
18 (5)
38 (2)
6–8 (8)
Inflow, km 3 /yr
300 (5)
23,967 (6)
473 (7)
Mean salinity
36 (5)
36 (2)
10–14 (8)
opposite direction (Marsili 1681). These first scientifically documented measurements of density currents provided indirect evidence for the slope of the sea level
associated with the density difference between the Black Sea and the Mediterranean
Sea. This discovery has motivated a number of challenging research efforts and is
still an active research topic because of the importance of strait exchanges for the
regional and global oceanography.
Runoff and precipitation over the Black Sea exceed evaporation resulting in a
net outflow of about 300 km 3 /yr (Unluata et al. 1990). One very coarse estimate of
water fluxes proposed by these authors would assume for the annual precipitation,
evaporation and river runoff values of 300, 350 and 350 km 3 , correspondingly (Table 5.1). However, according to Vorosmarty et al. (1997, 1998) monthly mean river
discharge ranges from 126 to 284 km 3 /yr (see also Kara et al. 2008). Furthermore
for the period 1923–1997, the mean values of evaporation and precipitation are estimated as E = 239 km 3 /yr and P = 378 km 3 /yr (Simonov and Altman 1991; Stanev
and Peneva 2002), which does not fit well with the above coarse estimates. The ratio
between the inflowing and outflowing water in the Bosporus Straits 1 scales as 18:36,
which is the rate between the salinities of the outflowing and inflowing waters.
Water exchange of the Baltic Sea (Table 5.1) presents approximately an annual
balance of an outflow of about 946 km 3 /yr of Baltic water with salinity of 8.5 and an
inflow of 473 km 3 /yr of water with salinity of 17 (Liljebladh and Stigebrandt 1996).
1 This notion is used here to denote the Bosporus (alternatively Bosphorus Strait, also known as the
Istanbul Strait) and the Dardanelles Strait.
133
Table 5.1 Characteristics of the basins and straits. References: (1) Unluata et al. (1990), (2) Mariotti et al. (2002), (3) Struglia et al. (2004), (4) HELCOM (1986), (5) Simonov and Altman
(1991), Stanev and Peneva (2002), (6) Baschek et al. (2001), (7) Liljebladh and Stigebrandt (1996),
(8) Döös et al. (2004), Meier et al. (2006). More estimates can be found in Tsimplis et al. (2006)
Black Sea
Mediterranean Sea
Baltic Sea
Basin
characteristics
Area, km 2
436,400
2,500,000
415,000
Volume, km 3
547,000
3,700,000
21,700
Mean depth, m
1,253
1,500
55
Maximum depth, m 2,212
5,267
459
Surface water
Budget
(km 3 /yr)/
(mm/yr)
Precipitation
300/687 (1)
827–1192/331–477 (2)
224/540 (4)
Evaporation
350/802 (1)
2335–2940/934–1176 (2) 184/443 (4)
River inflow
350/802 (1)
250–500/100–200 (3)
436/1050 (4)
Strait
Width (narrowest
section, km)
Bosporus 0.7 Gibraltar 14
Øresund 4,
Great Belt 16
Outflow, km 3 /yr
600 (5)
25,544 (6)
946 (7)
Mean salinity
18 (5)
38 (2)
6–8 (8)
Inflow, km 3 /yr
300 (5)
23,967 (6)
473 (7)
Mean salinity
36 (5)
36 (2)
10–14 (8)
opposite direction (Marsili 1681). These first scientifically documented measurements of density currents provided indirect evidence for the slope of the sea level
associated with the density difference between the Black Sea and the Mediterranean
Sea. This discovery has motivated a number of challenging research efforts and is
still an active research topic because of the importance of strait exchanges for the
regional and global oceanography.
Runoff and precipitation over the Black Sea exceed evaporation resulting in a
net outflow of about 300 km 3 /yr (Unluata et al. 1990). One very coarse estimate of
water fluxes proposed by these authors would assume for the annual precipitation,
evaporation and river runoff values of 300, 350 and 350 km 3 , correspondingly (Table 5.1). However, according to Vorosmarty et al. (1997, 1998) monthly mean river
discharge ranges from 126 to 284 km 3 /yr (see also Kara et al. 2008). Furthermore
for the period 1923–1997, the mean values of evaporation and precipitation are estimated as E = 239 km 3 /yr and P = 378 km 3 /yr (Simonov and Altman 1991; Stanev
and Peneva 2002), which does not fit well with the above coarse estimates. The ratio
between the inflowing and outflowing water in the Bosporus Straits 1 scales as 18:36,
which is the rate between the salinities of the outflowing and inflowing waters.
Water exchange of the Baltic Sea (Table 5.1) presents approximately an annual
balance of an outflow of about 946 km 3 /yr of Baltic water with salinity of 8.5 and an
inflow of 473 km 3 /yr of water with salinity of 17 (Liljebladh and Stigebrandt 1996).
1 This notion is used here to denote the Bosporus (alternatively Bosphorus Strait, also known as the
Istanbul Strait) and the Dardanelles Strait.