A rain forest is any area on earth that is heavily vegetated and receives at least 40 inches of rain every year.

Although forest fires do a lot of damage, they actually provide great benefits to forests. Because they eliminate undergrowth they allow trees more room to grow and often make future fires much less dangerous to people and animals.

Higher temperatures in cities are due to a phenomenon known as the urban heat island effect. Cities become urban heat islands as a result of extensive pavement, buildings, machinery, pollution and other changes that often accompany growing populations. A big city like Los Angeles can be up to five degrees hotter than its surrounding area thanks to the urban heat island effect.