THERMOHALINE CIRCULATION AND DYNAMIC STRUCTURE OF THE NORTH AEGEAN

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THERMOHALINE CIRCULATION AND DYNAMIC STRUCTURE OF
THE NORTH AEGEAN

• Dimitris GEORGOPOULOS
• National Centre for Marine Research

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GEOMORFOLOGY
EXISTING DATA
1908-1984
1985-1999
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METEOROLOGICAL CONDITIONS

• The prevailing winds are northerlies
• The secondary peak in frequency are Southerlies

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ETESIAN WINDS

• NOAA-AVHRR
• 31-8-87
• Visible

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UPEWLLINGS
NOAA-AVHRR HRPT of 4-9-1987
Summer wind stress distribution in the
Mediterrenean
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WATER MASSES

• Black Sea Water (BSW)
• Old BSW
• Levantine Surface Water (LSW)
• Levantine Intermediate Water (LIW)
• Deep and Bottom Water (DW)

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The distribution of BSW and LSW

• BSW occupies the northern and western parts of
  the N. Aegean
• The LSW occupies the eastern part of the Aegean
  up to the Limnos Plateau

BSW
BSW
LSW
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SEASONAL EVOLUTION OF BSW


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BSW

• Seasonal varibility of the BSW at station in the
  Limnos basin.

The net exchange through Dardanelles fluctuates
from 200km3/yr to 1000km3/yr. The mean inflow
in the AEGEAN is 1257km3/yr and outflow from the
AEGEAN is 957km3/yr

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LSW
LIA-4 Nov.-86
LIA-5 Mar.-87
LIA-6 Aug.-87
LIA-3 Sept.-86
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SEASONAL CHANGES OF THE WATER COLUMN

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DISTRIBUTION OF LIW

• AUGUST-SEPTEMBER 1986

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DISTRIBUTION OF LIW

• AUGUST-SEPTEMBER
• 1987

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DEEP AND BOTTOM WATEROF THE N. AEGEAN

Mean minimum temperature during the last 48 years
in Alexandroupolis meteo station
-0.1 1987
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DEEP AND BOTTOM WATER IN DIFFERENT BASINS


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10 year changes in the N. Aegean
The recent history of the Limnos Basin
1986 1987 - 1988 1993 1997
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10 year changes in the N. Aegean
The recent history of the North Skyros Basin
1986 1987 1988 1997
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DEEP AND BOTTOM WATER IN DIFFERENT BASINS
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SOURCES OF DEEP WATER IN THE N. AEGEAN
BSW
?
NAeW
?
?
?
NAeW
?
LIW
?
LSW
NAeW
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CONVEYOR BELT CONNECTING THE NORTH AND SOUTH
AEGEAN
?a? plateau Te?µa????
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THE DYNAMIC STRUCTURE
LIA-5 March 87
LIA-3 August 86

• MAIN DYNAMIC FEATURES
• Cyclone of Chios basin
• Anticyclones along the periphery of the Chios
  Cyclone
• North Sporades Cyclone
• Samothraki Anticyclone
• Athos anticyclone
• Current of the Eastern Aegean
• Thermohaline front of Limnos
• Thermohaline fronts where BSW meet LSW/LIW
• Upwellings

LIA-4 November 86
LIA-6 August 87