GEOGRAPHY AND CLIMATE

 

Tropical rainforests lie in the "tropics", between the Tropic of Capricorn and Tropic of Cancer. In this region sunlight strikes Earth at roughly a 90-degree angle resulting in intense solar energy. This intensity is due to the consistent day length on the equator: 12 hours a day, 365 days per year. This consistent sunlight provides the essential energy necessary to power the forest via photosynthesis.

Because of the ample solar energy, tropical rainforests like the Amazon are usually warm year round with temperatures from in the 72-93°F (22-34°C) range, although forests at higher elevations, especially cloud forests, may be significantly cooler. The temperature may fluctuate during the year, but in some equatorial forests the average may vary as little as a few degrees throughout the year. Temperatures are generally moderated by cloud cover and high humidity.

While the Amazon generally conforms to this pattern, parts of the basin periodically experience cold spells, when weather patterns bring cold air from Antarctica.