Antarctic convergence
The Antarctic Convergence or Meinardus Line is the zone in which cold, north-flowing surface water from Antarctica meets south-flowing warmer surface water from the north (the temperate zones of the Atlantic , Pacific and Indian Oceans ).
Since the water from Antarctica is colder, it has a higher density than the warmer water from the north. Therefore, it sinks to a depth of about 800 m at the convergence zone and flows northward. The Antarctic convergence can be recognized by the temperature of the surface water, which is around 8 ° C to the north of it, and at which convergence drops abruptly to below 2 ° C.
The Antarctic Convergence forms the northern limit of the Southern Ocean . Their location depends on longitude , weather and season and can therefore shift about 150 km north or south. It runs roughly between
- the 45th parallel in the area of the Indian Ocean and
- the 57th parallel in the area of Drake Street ,
- an average of about 49 degrees.
The following sub-Antarctic islands and archipelagos are scattered within this zone and are clearly to be regarded as polar :
- South Georgia and the South Sandwich Islands
- Peter I Island
- Bouvet Island
- Heard and McDonald Islands
- Macquarie Island
- Scott Island
- Balleny Islands .
See also
literature
- Sandford Moss and Luisa deLeiris (Illustr.): Antarctica. Ecology of a nature reserve. Spektrum Akademischer Verlag, Heidelberg, Berlin & New York 1992, ISBN 3-86025-051-5 .