Climate change can be considered at two board temporal scale : long-term changes at greater than 20.000 years, and short-terms changes between 100 and 20.000 years. Climate variabelity refers to mainly to decade to decade and year to year changes. Causes of climate change can be classified as either external or internal. The former includes changes of earth’s orbital geometry, often referred to as Milancovitch or astronomical variations. Internal causes result from changes to the basic nature of the components of the climate system and feedbacks between these components.
Currently there is the great concern about human-induced climate change mainly due to increased global pollution levels which have, through an enchanced greenhouse effect, the potential to increase the global temperatures, alter climate patters and raise sea levels. At the local to regional scale, deforestation and desertification are also of concern. Although the mangitude of climate change in the tropics is likely to be less than at higher latitudes, climate changes impacts will considerable. A full understanding of the gravity oh these changes will, however, only be achieved when the causes, nature and availability of climate resources in the tropics is fully appreciated. This will continue to be one of the main goals of tropical climatology.
Sources : McGregor, Glenn. 1998.Tropical Climate 2nd ed.Baffinslane : John willey and Sons
