Greenhouse gases are the biggest contributor to global warming and climate change all around the world. Greenhouse gases include, carbon dioxide, methane, nitrous oxide, and more. These gasses are created naturally, but by human activity as well. Some harmful activities and produce greenhouse gasses include burning fossil fuels, car and airplane fumes, and others. These gases create a blanket around the Earth, causing the heat from the sun to stay in the Earths atmosphere, instead of letting it back into space. Not all heat from the sun is supposed to reach the Earths surface. Only half of the heat supposed to, while 30% goes straight into the atmosphere, and 20% gets reflected straight back into space. The greenhouse effect prevents the heat from going back into space, and heats up the world. Another factor causing global warming, is the increasing amount of trees being cut down. Naturally, trees and other plants would absorb some of these gases. The amount of trees cut down, means that there are less trees to absorb the gases. Global warming influences changes in rainfall and causes floods. Extreme rainfall is caused when the hot air evaporates all the water on earth to the atmosphere. The more water evaporated, the more rain we can expect. The change in weather also causes hotter weather causing droughts or melting ice glaciers and rising sea levels. These changes influence the environments of animals on earth like polar bears and sea turtles. To polar bears, ice is extremely important. Since polar bears eat mostly fish and seals that are mostly in the middle of the ocean, they use ice to get there and catch their food. Lack of food is currently the number one reason of death in polar bears. This is especially harmful to cubs, causing the population of polar bears to decrease rapidly. Another problem with cubs is the fact that female cubs give birth during the winter and when cubs are newborn, they need a lot o