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The first storms and storm surge are behind us and here at home we were fortunate that everything stayed intact. Just a lid of the rain water barrels and the cover for our grill had taken to flight - but were later found in the ditch! On days like this there are always plenty of people about to watch the spectacle of a flood and the roaring sea. Thus, the monthly editorial solely refers to our very rough and gray North Sea! I hope this article makes you want to se(a) more and perhaps even poses the odd moment of - Well, I never...-!
Have fun with facts and figures Topic North Sea!!
Geography
The North Sea is an epeiric (or \"shelf\") sea on the European continental shelf, it connects to the ocean through the English Channel in the south and the Norwegian Sea in the north. It is more than 970 kilometres (600 mi) long and 580 kilometres (360 mi) wide, with an area of around 750,000 square kilometres (290,000 sq mi). The North Sea is bounded by the Orkney Islands and east coasts of England and Scotland to the west and the northern and central European mainland to the east and south, including Norway, Denmark, Germany, the Netherlands, Belgium, and France. In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively. In the north it is bordered by the Shetland Islands, and connects with the Norwegian Sea, which lies in the very north-eastern part of the Atlantic.
Geology
Map showing hypothetical extent of Doggerland
(c. 8,000 BCE), the a land bridge
between Britain and mainland Europe
Emergence
Shallow epicontinental seas like the current North Sea have existed on the European continental shelf for a very long time. The rifting that formed the northern part of the Atlantic Ocean during the Jurassic and Cretaceous periods, from about 150 million years ago, caused tectonic uplift in the British Isles. Since then, a shallow sea has almost continuously existed between the highs of the Fennoscandian Shield and the British Isles.This precursor of the current North Sea has grown and shrunk with the rise and fall of the eustatic sea level during geologic time. Sometimes it was connected with other shallow seas, such as the sea above the Paris Basin to the south-west, the Paratethys Sea to the south-east, or the Tethys Ocean to the south.
During the Late Cretaceous, about 85 million years ago, all of modern mainland Europe except for Scandinavia was a scattering of islands. By the Early Oligocene, 34 to 28 million years ago, the emergence of Western and Central Europe had almost completely separated the North Sea from the Tethys Ocean, which gradually shrank to become the Mediterranean as Southern Europe and South West Asia became dry land. The North Sea was cut off from the English Channel by a narrow land bridge until that was breached by at least two catastrophic floods between 450,000 and 180,000 years ago.
Since the start of the Quaternary period about 2.6 million years ago, the eustatic sea level has fallen during each glacial period and then risen again. Every time the ice sheet reached its greatest extent, the North Sea became almost completely dry. The present-day coastline formed after the Last Glacial Maximum when the sea began to flood the European continental shelf.In 2006 a bone fragment was found while drilling for oil in the north sea. Analysis indicated that it was a Plateosaurus from 199 to 216 million years ago. This was the deepest dinosaur fossil ever found and the first find for Norway.
Major features
For the most part, the sea lies on the European continental shelf with a mean depth of 90 metres (300 ft). The only exception is the Norwegian trench, which extends parallel to the Norwegian shoreline from Oslo to an area north of Bergen. It is between 20 and 30 kilometres (12 and 19 mi) wide and has a maximum depth of 725 metres (2,379 ft).
The Dogger Bank, a vast moraine, or accumulation of unconsolidated glacial debris, rises to a mere 15 to 30 metres (50–100 ft) below the surface. This feature has produced the finest fishing location of the North Sea. The Long Forties and the Broad Fourteens are large areas with roughly uniform depth in fathoms. These great banks and others make the North Sea particularly hazardous to navigate, which has been alleviated by the implementation of satellite navigation systems. The Devil\'s Hole lies 200 miles (320 km) east of Dundee, Scotland. The feature is a series of asymmetrical trenches between 20 and 30 kilometres (12 and 19 mi) long, 1 and 2 kilometres (0.62 and 1.2 mi) wide and up to 230 metres (750 ft) deep.
The North Sea receives freshwater from a number of European continental watersheds, as well as the British Isles. A large part of the European drainage basin empties into the North Sea including water from the Baltic Sea. The largest and most important affecting the North Sea are the Elbe and the Rhine – Meuse watershed. Around 185 million people live in the catchment area of the rivers that flow into the North Sea encompassing some highly industrialized areas.
Water circulation and tides
The North Sea is an arm of the Atlantic Ocean receiving the majority of ocean current from the northwest opening, and a lesser portion of warm current from the smaller opening at the English Channel. These tidal currents leave along the Norwegian coast. Surface and deep water currents may move in different directions. Low salinity surface coastal waters move offshore, and deeper, denser high salinity waters move in shore.
The main pattern to the flow of water in the North Sea is an anti-clockwise rotation along the edges. The North Sea located on the continental shelf has different waves than those in deep ocean water. The wave speeds are diminished and the wave amplitudes are increased. In the North Sea there are two amphidromic systems and a third incomplete amphidromic system. In the North Sea the average tide difference in wave amplitude is between 0 to 8 metres (0 to 26 ft).
The Kelvin tide of the Atlantic ocean is a semidiurnal wave that travels northward. Some of the energy from this wave travels through the English Channel into the North Sea. The wave still travels northward in the Atlantic Ocean, and once past the northern tip of Great Britain, the Kelvin wave turns east and south and once again enters into the North Sea.
http://en.wikipedia.org/wiki/North_Sea
Also nice for all German-speaking: http://www.die-ganze-nordsee.de/entstehung_nordsee.html
Have fun with facts and figures Topic North Sea!!
Geography
The North Sea is an epeiric (or \"shelf\") sea on the European continental shelf, it connects to the ocean through the English Channel in the south and the Norwegian Sea in the north. It is more than 970 kilometres (600 mi) long and 580 kilometres (360 mi) wide, with an area of around 750,000 square kilometres (290,000 sq mi). The North Sea is bounded by the Orkney Islands and east coasts of England and Scotland to the west and the northern and central European mainland to the east and south, including Norway, Denmark, Germany, the Netherlands, Belgium, and France. In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively. In the north it is bordered by the Shetland Islands, and connects with the Norwegian Sea, which lies in the very north-eastern part of the Atlantic.
Geology
Map showing hypothetical extent of Doggerland
(c. 8,000 BCE), the a land bridge
between Britain and mainland Europe
Emergence
Shallow epicontinental seas like the current North Sea have existed on the European continental shelf for a very long time. The rifting that formed the northern part of the Atlantic Ocean during the Jurassic and Cretaceous periods, from about 150 million years ago, caused tectonic uplift in the British Isles. Since then, a shallow sea has almost continuously existed between the highs of the Fennoscandian Shield and the British Isles.This precursor of the current North Sea has grown and shrunk with the rise and fall of the eustatic sea level during geologic time. Sometimes it was connected with other shallow seas, such as the sea above the Paris Basin to the south-west, the Paratethys Sea to the south-east, or the Tethys Ocean to the south.
During the Late Cretaceous, about 85 million years ago, all of modern mainland Europe except for Scandinavia was a scattering of islands. By the Early Oligocene, 34 to 28 million years ago, the emergence of Western and Central Europe had almost completely separated the North Sea from the Tethys Ocean, which gradually shrank to become the Mediterranean as Southern Europe and South West Asia became dry land. The North Sea was cut off from the English Channel by a narrow land bridge until that was breached by at least two catastrophic floods between 450,000 and 180,000 years ago.
Since the start of the Quaternary period about 2.6 million years ago, the eustatic sea level has fallen during each glacial period and then risen again. Every time the ice sheet reached its greatest extent, the North Sea became almost completely dry. The present-day coastline formed after the Last Glacial Maximum when the sea began to flood the European continental shelf.In 2006 a bone fragment was found while drilling for oil in the north sea. Analysis indicated that it was a Plateosaurus from 199 to 216 million years ago. This was the deepest dinosaur fossil ever found and the first find for Norway.
Major features
For the most part, the sea lies on the European continental shelf with a mean depth of 90 metres (300 ft). The only exception is the Norwegian trench, which extends parallel to the Norwegian shoreline from Oslo to an area north of Bergen. It is between 20 and 30 kilometres (12 and 19 mi) wide and has a maximum depth of 725 metres (2,379 ft).
The Dogger Bank, a vast moraine, or accumulation of unconsolidated glacial debris, rises to a mere 15 to 30 metres (50–100 ft) below the surface. This feature has produced the finest fishing location of the North Sea. The Long Forties and the Broad Fourteens are large areas with roughly uniform depth in fathoms. These great banks and others make the North Sea particularly hazardous to navigate, which has been alleviated by the implementation of satellite navigation systems. The Devil\'s Hole lies 200 miles (320 km) east of Dundee, Scotland. The feature is a series of asymmetrical trenches between 20 and 30 kilometres (12 and 19 mi) long, 1 and 2 kilometres (0.62 and 1.2 mi) wide and up to 230 metres (750 ft) deep.
The North Sea receives freshwater from a number of European continental watersheds, as well as the British Isles. A large part of the European drainage basin empties into the North Sea including water from the Baltic Sea. The largest and most important affecting the North Sea are the Elbe and the Rhine – Meuse watershed. Around 185 million people live in the catchment area of the rivers that flow into the North Sea encompassing some highly industrialized areas.
Water circulation and tides
The North Sea is an arm of the Atlantic Ocean receiving the majority of ocean current from the northwest opening, and a lesser portion of warm current from the smaller opening at the English Channel. These tidal currents leave along the Norwegian coast. Surface and deep water currents may move in different directions. Low salinity surface coastal waters move offshore, and deeper, denser high salinity waters move in shore.
The main pattern to the flow of water in the North Sea is an anti-clockwise rotation along the edges. The North Sea located on the continental shelf has different waves than those in deep ocean water. The wave speeds are diminished and the wave amplitudes are increased. In the North Sea there are two amphidromic systems and a third incomplete amphidromic system. In the North Sea the average tide difference in wave amplitude is between 0 to 8 metres (0 to 26 ft).
The Kelvin tide of the Atlantic ocean is a semidiurnal wave that travels northward. Some of the energy from this wave travels through the English Channel into the North Sea. The wave still travels northward in the Atlantic Ocean, and once past the northern tip of Great Britain, the Kelvin wave turns east and south and once again enters into the North Sea.
http://en.wikipedia.org/wiki/North_Sea
Also nice for all German-speaking: http://www.die-ganze-nordsee.de/entstehung_nordsee.html
