Global warming affects temperature, it causes it to rise over time. The rise in temperatures affects something called the greenhouse effect. The greenhouse effect is when the sun's rays are trapped by the ozone layer and increases the heat and temperature even more. Emissions from fossil fuels (petroleum) add to pollutants in the atmosphere, this intensifies the greenhouse effect.
Because of the increased heat, sea levels will rise due to the melting of polar ice. Some think that the rises in temperature will hit 130-150 F in the next 20-30 years.This will cause widespread flooding. Some authors say that the southern part of Florida will be underwater.