Tropical climate

Tropical climate is the first of the five major climate groups in the Köppen climate classification identified with the letter A. Tropical climates are defined by a monthly average temperature of 18 °C (64 °F) or higher in the coolest month, featuring hot temperatures and high humidity all year-round. Annual precipitation is often abundant in tropical climates, and shows a seasonal rhythm but may have seasonal dryness to varying degrees. There are normally only two seasons in tropical climates, a wet (rainy/monsoon) season and a dry season. The annual temperature range in tropical climates is normally very small. Sunlight is intense in these climates.

There are three basic types of tropical climates within the tropical climate group: tropical rainforest climate (Af), tropical monsoon climate (Am) and tropical savanna or tropical wet and dry climate (Aw for dry winters, and As for dry summers), which are classified and distinguished by the precipitation levels of the driest month in those regions.

The Köppen climate classification is the most widely used climate classification system. It defines a tropical climate as a region where the mean temperature of the coldest month is greater than or equal to 18 °C (64 °F) and does not fit into the criteria for B-group climates, classifying them as an A-group (tropical climate group). A-group regions are usually found in the tropics, below 23.5 latitude in both the southern and northern hemisphere; they include areas around the Equator, Central America, North-central portions of South America, central Africa, southern portions of Asia and parts of North Australia and the Pacific Ocean islands.

In Group A, there are three types of this climate: the tropical rainforest climate (Af), tropical monsoon climate (Am) and tropical wet and dry or savanna climate (Aw or As). All of the three climates are classified by their P_dry (short for precipitation of the driest month). Tropical rainforest climate's P_dry should be greater than or equal 60 mm (2.4 in). Tropical monsoon climate's P_dry should be in the range from ${\displaystyle (100-{\tfrac {mean\ annual\ precipitation\ in\ mm}{25}})}$ to 60 mm. Tropical wet and dry or savanna climate's P_dry should be less than ${\displaystyle (100-{\tfrac {mean\ annual\ precipitation\ in\ mm}{25}})}$.

Tropical climates normally have only two seasons, a wet season and a dry season. Depending on the location of the region, the wet and dry seasons can have varying duration. Annual temperature changes in the tropics are small. Due to the high temperatures and abundant rainfall, much of the plant life grows throughout the year. High temperature and humidity is the most suitable environment for epiphytes to grow. In many tropical climates, vegetation grows in layers: shrubs under tall trees, bushes under shrubs and grasses under bushes. Tropical plants are rich in resources, including coffee, cocoa and oil palm. Listed below are the types of vegetation unique to each of the three climates that make up the tropical climate biome.

Tropical rainforest vegetation including: Bengal bamboo, bougainvillea, curare, coconut tree, durian and banana.

Tropical monsoon vegetation including: teak, deodar, rosewood, sandalwood and bamboo.

Tropical wet and dry or savanna vegetation including: acacia senegal, elephant grass, jarrah tree, gum tree eucalyptus and whistling thorn.