Climate, Tropical

Tropical climates are located along the earth's equatorial belt between the latitudinal belts [Page 280]of the Tropic of Cancer and the Tropic of Capricorn. It is over these latitudes where the solar energy from the sun enters the atmosphere more directly than in higher latitudes throughout the year. There is also less of a seasonal shift in the solar energy coming into tropical areas than seasonal shifts that occur over higher latitudes. This means throughout the year, solar energy is high, and both the ocean and land surfaces over tropical latitudes are warm year-round.

Tropical climates, especially over oceans, have the lowest annual range in temperature than any other climate on earth. It is often the case that the diurnal temperature range in tropical climates exceeds the annual temperature range, which is usually only 3–6 degrees C (5–10 degrees F). Throughout the year, nighttime temperatures are usually between 21–27 degrees C (70–80 degrees F), while daytime temperatures are 30–35 degrees C (86–95 degrees F). Temperatures below 16 degrees C (61 degrees F) or above 38 degrees C (100 degrees F) are rare. High humidity and warm nights can make some days uncomfortable, although excessively high temperatures are rare. Much cooler temperatures, however, can be found within the tropical belt at higher elevations, especially in locations such as the Andes Mountains in South America.

In most tropical locations closest to the equator, the precipitation is high and some have a monsoon climate.

Tropical climates are also the most humid climates found on earth. These climates cover the highest amount of ocean surface than any other climate, and the intense amount of solar energy over tropical oceans creates a high amount of evaporation and cloud convection. Precipitation is frequent and heavy over tropical oceans and land areas, with an annual precipitation range usually between 79–157 inches (2,000–4,000 millimeters). Generally, in most tropical locations closest to the equator, the precipitation is high each month of the year, and there is no particular dry season. The world's tropical rainforests are found in these types of climates.

In tropical climates found in slightly higher latitudes, annual precipitation is high; however, there is usually a wet season and a dry season. Some tropical locations even have a monsoon climate. Often, areas of tropical climates with wet and dry seasons are the savannah areas between wet tropical and drier subtropical locations. Locations of wet and dry season tropical climates are found in the southern Mexican pacific coast, Venezuela, Brazil, the African savannah regions, India, southeast Asia, and northern Australia. The tropical monsoon climates have the greatest wet-to-dry precipitation regime. These climates are most prevalent on the African tropical west coast and tropical southeast Asia. In some locations, precipitation during the wet season amounts to more than 197 inches (5,000 millimeters). The tropical monsoon climates occur where there are seasonal changes in the surface heating of the land and the oceans. During the season when more solar energy is directed over the oceans, dry air flows over the land toward the ocean, where convection occurs and the land areas remain dry. When the season changes and more solar energy is directed over the land surface, the winds shift and bring moisture from the ocean surface over the land, where convection and precipitation occur.

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