The greenhouse effect and global warming are issues that geologists talk about all the time. The greenhouse effect is a natural process that keeps the earth at livable temperatures. The sun's energy warms the earth when its heat rays are absorbed by greenhouse gases and become trapped in the atmosphere. Some of the most common greenhouse gases are water vapor, carbon dioxide, and methane. If there were no greenhouse gases, very few rays would be absorbed and the earth would be extremely cold. When too many rays are absorbed, the Earth's atmosphere begins to warm, causing global warming. Global warming can lead to many problems that affect the environment we live in. To talk about global warming, we first need to understand what causes the greenhouse effect. Many of the sun's rays are absorbed by water vapor naturally present in our atmosphere. Water vapor accounts for 80% of natural greenhouse warming. Is the remaining 20% ​​due to other gases present in very small quantities? (Murck, Skinner, and Porter 488). Carbon dioxide is also a great absorber of the sun's heat rays. Humans can cause the release of a large amount of carbon dioxide. Every time we burn fossil fuels, we release more carbon dioxide. Emissions from automobiles also increase the amount of carbon dioxide in the atmosphere. If there is more carbon dioxide in the atmosphere, more sunlight will be absorbed. This will cause a warming of the atmosphere and the earth's temperature. The warming of the earth will cause the oceans to become warmer. As they warm, more water evaporates, causing more carbon dioxide to be released into the atmosphere. Once this process begins, it is extremely difficult to control. If the temperature continues to rise, more carbon dioxide will be released. Another greenhouse gas is methane: ?Methane absorbs infrared radiation 25 times more effectively than carbon dioxide, making it an important greenhouse gas despite its relatively low concentration? (490). Many studies have been conducted on how methane is released into the atmosphere. Methane in the atmosphere is "generated by biological activity related to rice cultivation, leaks in domestic and industrial gas pipelines, and the digestive process of domestic livestock, particularly cattle." (490). One environmental effect of global warming is that higher temperatures will lead to a change in the water cycle. Some places may experience more rain. Warmer temperatures will cause more evaporation from lakes, rivers and oceans. In some areas this may be the case