In the tropical rain forest biome, the climate is usually quite steady throughout the year, with average temperatures between 70 and 85 degrees Fahrenheit. Tropical rain forests also have very high average humidity, with an average high between 77 and 88 percent humidity throughout the year.
In addition to the high humidity, tropical rain forests are also categorized by very high levels of precipitation. In fact, a region must receive at least 50 inches of rainfall a year to be labelled as a tropical rain forest. Most receive much more than this, with some areas receiving as much as 400 inches in a single year. Some areas may have separate dry and rainy seasons, especially those in monsoonal areas.
Almost all tropical rain forests are located near the earth's equator, which means that they receive almost exactly 12 hours of light and 12 hours of darkness each day throughout the year. They are characterized by having incredibly tall trees that block approximately 98 percent of sunlight from reaching the ground. In addition, tropical rain forests contain more species of trees and plant life than any other type of forest or environment on the planet. It is estimated that rain forests are home to more than 15 million different species of plants and animals.