Dissolved oxygen in seawaterDissolved oxygen in seawaterUnits and ranges

Dissolved oxygen in seawater ranges Dissolved oxygen in seawater ranges from 0from 0--10 mg L10 mg L--11

The atomic mass of OThe atomic mass of O22 (32g) (32g) corresponds to 22.4 litres at STP, so 5 corresponds to 22.4 litres at STP, so 5 ml Lml L--1 1 = 5 X 32/22.4 i.e. about 7 mg L= 5 X 32/22.4 i.e. about 7 mg L--11

The maximum oxygen concentration The maximum oxygen concentration in seawater (~ 7 ml Lin seawater (~ 7 ml L--11) is therefore ) is therefore about 30 times lower than in air (200/7)about 30 times lower than in air (200/7)

The solubility of oxygen depends on The solubility of oxygen depends on the salinity and temperature of the the salinity and temperature of the water. 0 5

10 15 20 25 30 35

0

12.525

37.5

0

2

4

6

8

10

12

14

16

14-1612-1410-128-106-84-62-40-2

O2(mgL-1)

T (o C)

O2(mg L-1)

OO22 is usually measured in mg Lis usually measured in mg L--11 or ml Lor ml L--11

water.

Salinity

Fontes e poços de oxigénio Fontes e poços de oxigénio dissolvido na água do mar

Fontes

Poços

Mistura

dissolvido na água do mar

Rearejamento I0

Oceano

Atmosfera

δIδz

= - kI

1% I0Luz (µmol m-2 s-1)

Produçãoprimária

Advecção& difusão

Zona fóticaProfundidadede compensação Zona disfótica

Consumo heterotrófico

Decomposição por bactérias Profundidade z (m)

Unidades de radiaçãoUnidades de radiação

Unidade Conversão em Tipo Significado/Comentários

lux (lx) 6 X 10-6 ly min-1 Luz à superfície do oceanolux (lx) 1 IC m-2 Fluxo (iluminação/tempo)international candle (IC) Iluminaçãolangley 1 gcal cm-2 Energia/áreaeinstein (1 mol) 6.02 X 1023 quanta Energiaeinstein 52000 gcal Energia para λ=550 nmgcal 4.185 Joule Energiaµeinstein m-2 s-1 Densidade de 500-1500 (aprox.)

potência (à superfície do oceano)wm-2 1 J s-1 m-2 Densidade de 200-600 (aprox.)

potência (à superfície do oceano)

Adaptado de: Parsons, Takahashi & Hargrave, 1984. Biological Oceanographic Processes 3rd. Ed. e Jërlov - Light in the Sea

Surface

0 10 20 km

GISGIS -- Dissolved OxygenDissolved OxygenTagusTagus estuaryestuarySummer Winter

Surface

0 10 20 km

Summer D.O. (mg/l)

Bottom Winter D.O. (mg/l)

0 10 20 km

Bottom

0 10 20 km

GISGIS -- Dissolved OxygenDissolved OxygenTagusTagus estuary estuary -- SummerSummer

Surface

0 10 20 km

Bottom

0 10 20 km

D.O. (mg/l)

Surface - Bottom

0 10 20 km

Surface - BottomD.O. (mg/l)

GISGIS -- Dissolved OxygenDissolved OxygenTagusTagus estuary estuary -- WinterWinter

Surface D.O. (mg/l)

0 10 20 km

Bottom

0 10 20 km

Surface - Bottom

0 10 20 km

Surface - BottomD.O. (mg/l)

Surface

0 10 20 km

GISGIS -- Oxygen SaturationOxygen SaturationTagusTagus estuaryestuarySummer Winter

Surface

0 10 20 km

Summer Oxygen Sat (%)

Bottom Winter Oxygen Sat (%)

0 10 20 km

Bottom

0 10 20 km

GISGIS -- Oxygen SaturationOxygen SaturationTagusTagus estuary estuary -- SummerSummer

Surface Oxygen Sat (%)

0 10 20 km

Bottom

0 10 20 km

Surface - Bottom

0 10 20 km

Surface - BottomOxygen Sat (%)

GISGIS -- Oxygen SaturationOxygen SaturationTagusTagus estuary estuary -- WinterWinter

Surface Oxygen Sat (%)

0 10 20 km

Bottom

0 10 20 km

Surface - Bottom

0 10 20 km

Surface - BottomOxygen Sat (%)

Tejo estuary Tejo estuary –– dissolved oxygen in dissolved oxygen in the maximum turbidity zonethe maximum turbidity zone

Data from BarcaWin2000

2

4

6

8

10

12

14

O2

(mg

L-1)

Oxygen sag

0 50 100 150 200 250 300 350 400

Julian day

Tejo estuary Tejo estuary –– D.O. And % saturation OD.O. And % saturation O22in the maximum turbidity zonein the maximum turbidity zone

Dis

solv

ed o

xyge

n (m

g L-1

)

2

4

6

8

10

12

14

20

40

60

80

100

120

140

160

Perc

enta

ge s

atur

atio

n O

2(%

)

% saturation

D.O.

0 50 100 150 200 250 300Julian day

350 400

Data from BarcaWin2000

Black Sea Black Sea –– Location Location

http://www.ancientrade.com/

Black Sea Black Sea –– SeaWifs image SeaWifs image

http://daac.gsfc.nasa.gov

Bosporus

Danube estuary

Black Sea Black Sea –– Surface temperaturesSurface temperatures

http://www.grid.unep.ch/

Black Sea Black Sea –– CirculationCirculationFreshwater input from the NW coastFreshwater input from the NW coast

Name Catchment Length Total Total Sediment area runoff runoff dischargekm2 km km3 y-1 m3 s-1 106 t y-1

Danube 817000 2860 208 6596 51.7Dnieper 505810 2285 51.2 1624 2.12Dniester 71990 1328 10.2 323 2.5Southern Bug 68000 857 3 95 0.53Chorokh 22000 500 8.69 276 15.13Rioni 13300 228 12.8 406 7.08Inguri 4060 221 4.63 147 2.78Kodori 2030 84 4.08 129 1.01Bzyb 1410 - 3.07 97 0.6Yesilrmak - 416 4.93 156 18Kizilrmak - 1151 5.02 159 16Sakarya - 790 6.38 202 -Total 1505600 8363 306 9693 83

http://www.grid.unep.ch/

Black Sea Black Sea –– CirculationCirculation

http://daac.gsfc.nasa.gov/