The surface area of the Earth between the Tropic of Cancer (latitude 23.5° N) and the Tropic of Capricorn (latitude 23.5° S) represents the Tropics, or the Equatorial Zone. The Equator is at 0° latitude. The word “tropics” might conjure images of lush, steamy rainforest but surprisingly over 75% of the tropical belt endures periods of annual drought. The Tropics include desert, savanna, woodland, wetland, and rainforest, each with its own distinct climate, flora, and fauna. Prevailing wind conditions, elevation, and distance from the ocean are all contributing factors in the different tropical climates.
Rainforest plants grow in four distinct layers: the giant emergent trees, the towering canopy of broadleaf evergreen trees, the shorter understory (or lower canopy) trees intertwined with vines and shrubs, and the shady forest floor. Rainforests experience annual rainfall exceeding 2 meters (80–90 in), sometimes more than 7.5 meters (300 in or 25 feet)!