Page 13 - Curriculum Visions Dynamic Book

Greenhouse Effect: an increase of the global air temperature as a result of heat released from burning fossil fuels being absorbed by carbon dioxide in the atmosphere.
vapour: the gaseous form of a substance that is normally a liquid. For example, water vapour is the gaseous form of liquid water.
 The decay of organic matter is important in releasing carbon to the cycle. Normally leaves decay within a few years, which is why there is rarely thick leaf litter on the ground. Only where the ground is permanently waterlogged, such as in still-water marshes and bogs, can organic material accumulate. When it does so, it locks up carbon. Major swamps have occurred in many periods of geological history. These eventually became buried, forming coal deposits, oil and natural gas reserves.
 Clear-cutting trees has a major effect on
the natural carbon cycle because it removes a natural carbon-absorbing part of the environment (called a carbon “sink”). To maintain balance in the carbon cycle, trees have to be replanted in the same quantities that they are felled. This is happening in the temperate lands, but not in the tropics.
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