The Earth seen from satellites|
Information from Earth observation satellites is an important source of information for many research tasks and practical application both at a local, regional and global level. The satellites help us to gain increased understanding of the planet where we live, and contribute to providing better foundations for decisions.
As examples we may mention the wish to obtain a better general view of the development of the climate on the Earth, protection of biological diversity and important biotopes, contribution to sustainable development and increased quality of life for human beings and animals.
|Weather situations in Norway and Northern Europe|
|In the weather forecast for Norway we often hear that “a strong area of low pressure is developing near Iceland and will gradually move in towards the coast of Western Norway”.
This educational example will give a background for a better understanding of how satellite information may be used in connection with analysis of a development of areas of low pressure and at the formation of polar fronts.
|Storm on the western coast of Norway 1998|
|Mitch is the strongest hurricane that has been measured in the Caribbean since 1969 and the fourth strongest tropical hurricane that has ever been recorded.
Remnants of Mitch reached Western Norway about noon on 9th November 1998. The wind remained strong all through the afternoon until becoming weaker towards evening.
|The ocean in motion|
|Ocean currents transport warm and cold water over enormous territories. Many of these currents are fundamental to the climate of the areas.
Satellites are important tools for rapid supervision of large ocean areas, surveying current changes and contributing to increased knowledge about the pattern of ocean currents.
|Sea ice in the Arctic |
|The Arctic is the most northerly area of the globe. The Arctic ocean areas are entirely or partly covered by sea ice most of the year. Central or western parts of the Arctic basin are covered with ice all the year round, while the areas near the coast are mainly free of ice in summer.
Studies of satellite data during the past 20 years show that the ice in the Arctic has receded over an area as large as the whole of France.
|Algae in the ocean|
|Phytoplankton are small plants or algae. Algae are microscopic plants. They consist of one or some few cells and live in water. Separately phytoplankton may only be seen in an electronic microscope. They are only some few micrometers in size so that several thousand algae cells may be squeezed on to the head of a pin.
Microscopic phytoplankton are referred to as algae. If there are enough of them in the water, they may also be "seen" from satellites in orbits 800 kilometres above the surface of the Earth.
|Is the ozone layer getting thinner?|
|In the hole in the ozone layer in Antarctica total ozone values of down to 90-100 dobson units has been observed. This constitutes a reduction of 70 percent compared to measurments made before the hole was established. In the Arctics it happens that total ozone plumments down to below 200 dobson units. Since 1979 there has been a 0.4 percent average reduction of the ozone layer.|
|Oil spill and ship traffic - satellites can control|
|It has been estimated that intentional and illegal spills of this type into the oceans amount to 3 mill. tons per year. Accidents on the oil rigs and escapes through pipelines between offshore-fields and the mainland are also sources of oil pollution of the oceans.|