Greenhouse Effect
There's gases that trap this infrared heat clos to the Earth's surface. The gases are called Greenhouse Gases and the trapping of heat near the Earth surface is called the Greenhouse Effect. the green house effect is good because if it wasn't for it life would not exist in this planet. The greenhouse acours naturally, but it increases more when we burn fossil fuels. some of this greenhouse gases are Water Vapor (H2O), Carbon Dioxide (CO2), Methane (CH4), Nitrous Oxide (N2O) and Ozone (O3).
Credits: http://upload.wikimedia.org/wikipedia/commons/d/d5/The_green_house_effect.svg
Credits: http://upload.wikimedia.org/wikipedia/commons/d/d5/The_green_house_effect.svg