Name: BALTEX water and heat balances
File: baltex-bridge water and heat.doc
Date: 2005-03-14
By: Omstedt and Nohr
Comments: This files contains estimated water and heat balance components for the
BALTEX/Bridge period as well as longer periods.
References:
Omstedt, A. and C., Nohr (2004). Calculating the water and heat balances of the Baltic Sea
using ocean modelling and available meteorological, hydrological and ocean data. Tellus
56A, 400-414.
Table 1. Estimated annual mean volume flows for the Baltic Sea (order of magnitude).
The flows are denoted by: inflow (Qi), outflow (Qo), net precipitation (P-E), river runoff
(Qr), the volume change due to ice advection from the Baltic Sea (Qice), the volume
change due to land uplift (Qrise), the groundwater inflow (Qg ), the volume changes due to
thermal expansion (QT) and salt contraction (QS). As denotes the Baltic Sea surface area.
Qi
Qo
Qo-Qi
(P-E)AS Qr
Qice
Qrise
Qg
QT
QS
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
105
–105
–104
103
104
–102
–101
102
±102
±101
1
Table 2. Mean water balance for the Baltic Sea (the Belt Sea and the Kattegat excluded)
average. Unit: 103 m3 s-1. The flows are denoted as: River runoff (Qr), net precipitation
(P-E), inflow (Qi), outflow (Qo), and storage change. As denotes the Baltic Sea surface
area.
Qi
Qo
Qo-Qi
Qr
As(P-E)
Storage change
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
(m3s-1)
38.44
56.32
17.88
14.88
2.05
–0.95
AUTHOR
PERIOD
BALTEX/BRIDGE
Present
2000–2002
Present
42.75
59.41
16.76
14.96
1.70
–0.11
1979–2002
2
Table 3. Estimated annual mean heat fluxes for the Baltic Sea (order of magnitude). The
fluxes are denoted as: net heat flux (Fn), sun radiation to the open water surface (Fso), heat
flow from water to ice (Fwi), sun radiation through ice (Fsi), the heat fluxes associated with
precipitation in the form of rain (Fprec) and snow (Fsnow), the heat sink associated with ice
advection from the Baltic Sea (Fice), heat flows associated with river runoff and ground
water flow Fr and Fg, the heat fluxes associated with inflows (Fi) and outflows (Fo), and the
total heat loss to the atmosphere (Floss) . The fluxes are positive when going from the water
to the atmosphere.
Fn
Fso
Fwi
Fsi
Fprec
Fsnow
Fice
Fr
Fg
Fo–Fi
Floss
(Wm) (Wm-2) (Wm-2) (Wm-2) (Wm-2) (Wm-2) (Wm-2) (Wm-2) (Wm-2) (Wm-2) (Wm-2)
102
–102
100
–100
10-1
10-1
–10-1
10-1
10-1
–100
100
3
Table 4. Mean heat balance of the Baltic Sea (the Belt Sea and the Kattegat excluded).
The fluxes are positive when going from the water to the atmosphere. The fluxes are
denoted as: sensible heat (Fh), latent heat (Fe), net long-wave radiation (Fl), sun radiation
to the open water surface (Fs o), sun radiation through ice (Fs i), heat flow from water to
ice (Fw i), and net heat loss Floss = (1-Ai)(Fh+Fe +Fl+Fs o)+ Ai(Fs i + Fw i ), where Ai is the
ice concentration.
Fh
Fe
Fl
Fso
F wi
Fsi
Floss
(Wm-2)
(Wm-2)
(Wm-2)
(Wm-2)
(Wm-2)
(Wm-2)
(Wm-2)
10
37
37
–88
3
–0
–0
AUTHOR
PERIOD
BALTEX/BRIDGE
Present
2000–2002
Present
9
35
36
–85
4
–0
–1
1970–2002
4
Table 5. A comparison between fluxes calculated by the PROBE-Baltic model and the
HIRLAM-BALTEX model. For details of the nomenclature see Table 3.
Fh
Fe
Fl
Fso
Floss
(Wm-2)
(Wm-2)
(Wm-2)
(Wm-2)
(Wm-2)
7
44
54
–123
–18
1999–2000
7
38
38
–88
–5
1999–2000
AUTHOR
PERIOD
Fortelius
(2002, pers
com.)
Present
5
Appendix A. Calculated major components in the water and heat
balances during the BALTEX/BRIDGE period
Table 6. Monthly mean water balance for the Baltic Sea (the Belt Sea and the Kattegat
excluded). The flows are denoted as: difference between outflows and inflows (Qo-Qi),
river runoff (Qr), net precipitation (P-E), storage change, and As the Baltic Sea surface
area.
Year
Month
1999
1999
1999
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2002
2002
2002
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
Qo-Qi
(103 m3s-1)
9.98
1.53
10.31
4.67
24.27
40.99
30.67
-0.57
16.50
26.25
21.66
36.66
-15.26
26.68
2.22
36.31
4.91
38.54
3.91
10.50
23.94
8.30
11.70
37.04
-18.62
17.59
5.54
-9.57
16.89
59.75
Qr
(103 m3s-1)
10.59
10.37
10.65
10.87
12.48
14.56
19.27
21.24
17.76
18.54
17.78
13.74
11.37
14.47
14.44
12.16
12.01
12.60
17.48
21.39
16.91
15.26
15.76
16.56
14.98
14.11
11.82
12.16
12.01
12.60
As(P-E)
(103 m3s-1)
-2.02
-4.96
0.29
-1.19
2.49
1.96
4.68
1.99
5.36
8.23
-1.93
-8.05
2.02
5.79
0.52
-0.45
-0.89
0.42
6.31
2.13
5.89
1.43
0.44
3.44
-1.40
-6.88
-6.19
4.03
5.94
2.33
Storage change
(103 m3s-1)
-1.41
3.88
0.63
5.00
-9.30
-24.47
-6.73
23.80
6.62
0.52
-5.81
-30.96
28.64
-6.42
12.74
-24.60
6.21
-25.52
19.87
13.02
-1.14
8.39
4.49
-17.03
32.19
-10.36
0.09
25.76
1.06
-44.82
6
Table 7. Monthly mean heat balance of the Baltic Sea (the Belt Sea and the Kattegat
excluded). The fluxes are positive when going from the water to the atmosphere. The
fluxes are denoted as: sensible heat (Fh), latent heat (Fe), net long-wave radiation (Fl), sun
radiation to the open water surface ((Fso), heat flow from water to ice (Fwi), net heat loss
(Floss ), and Ai the calculated Baltic Sea monthly mean ice coverage.
YEAR
1999
1999
1999
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2002
2002
2002
MND
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
Fh
(Wm-2)
23
26
48
20
5
5
-11
-17
-18
-5
4
15
10
19
32
31
39
9
-8
-17
-16
-6
4
16
13
41
65
18
5
1
Fe
(Wm-2)
70
54
61
36
17
23
5
14
17
25
50
73
43
39
43
41
41
19
6
12
11
38
56
62
45
82
65
25
20
17
Fl
(Wm-2)
45
45
51
42
32
33
28
36
29
26
39
55
35
32
44
42
45
31
26
37
29
35
39
37
37
53
53
29
30
33
Fso
(Wm-2)
-34
-10
-4
-8
-22
-56
-112
-189
-200
-170
-141
-94
-34
-9
-4
-7
-24
-49
-100
-190
-197
-201
-143
-75
-34
-11
-4
-6
-22
-59
Fwi
(Wm-2)
0
0
0
6
10
9
7
0
0
0
0
0
0
0
0
0
15
11
10
0
0
0
0
0
0
0
1
10
9
7
Floss
(Wm-2)
104
115
157
97
41
13
-83
-155
-170
-124
-49
49
54
80
115
107
116
20
-67
-158
-173
-134
-45
40
62
165
180
75
42
-1
Ai
0
0
0
0.14
0.29
0.30
0.17
0
0
0
0
0
0
0
0
0
0.22
0.38
0.18
0
0
0
0
0
0
0
0.02
0.27
0.28
0.27
7