Life can be found in almost any terrestrial environment. But when discussing the climate system is to consider the biosphere as a discrete component, like the atmosphere, oceans and cryosphere.
The biosphere affects the albedo of the Earth, both on land and in oceans. Large areas of forest continental albedo is low compared with areas without vegetation such as deserts. The albedo of a deciduous forest is approximately 0.15 to 0.18, where a forest of conifers is between 0.09 and 0.15. A tropical rain forest reflects even less, between 0.07 and 0.15. In comparison, the albedo of a desert sand is about 0.3. It is clear that the presence of forests affects the energy budget of the climate system.
Some scientists believe that burning fossil fuels is not as destabilizing as the logging and destruction of ecosystems that sustain primary production in the oceans (Anderson et al, 1987).
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The biosphere also affects the flow of some greenhouse gases such as carbon dioxide and methane. The plankton of the ocean surface using the dissolved carbon dioxide for photosynthesis. This establishes a flow of gas, with the ocean, in fact setting gas from the atmosphere. At death, plankton, carries carbon dioxide to the deep ocean. The primary productivity by a factor of 4 reduces the atmospheric concentration of carbon dioxide and significantly weakens the greenhouse effect natural land.
It is estimated that up to 80% of the oxygen produced by photosynthesis is the result of the action of ocean algae, especially the coastal areas. Therefore the water pollution in these areas could be very destabilizing (Anderson et al, 1987).
The biosphere also affects the amount of aerosols in the atmosphere. Billions of spores, viruses, bacteria, pollen and other organisms are carried by wind and solar radiation incident affecting, influencing the global energy budget. Oceanic primary productivity produces compounds known as dimetilsulfitos, which are oxidized in the atmosphere to form sulfate aerosols, which serve as condensation nuclei for water vapor, thereby assisting the formation of clouds. The clouds themselves have a complex effect on the energy budget climate. So any change in the primary productivity of oceans, may indirectly affect the global climate.
There are of course many other mechanisms and processes that affect and are connected to the rest of the climate system.
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