Global warming or climate change. A major problem in our world today. Observed global temperature increases. The main cause of the problem is caused by greenhouse gases. Greenhouse gases are important to the world because of carbon dioxide or methane, will retain some heat in the world not to be reflected back to the atmosphere at all. Otherwise, the whole world is like the moon. The very cold at night and hot during the day because of the atmosphere to filter the power from the sun. Which makes the world warmer