Much like Venus, Earth is heating up due to the increase in carbon dioxide, which contributes to the green house effect. This phenomenon contributes to raising the average surface temperature about 35 degrees Celsius and is responsible for much of the polar ice caps melting to water. What's worse is that the carbon dioxide that is currently heating up the surface temperature is still increasing due to the increase in industrial production and automobile exhaust.
On the planet Venus, the same effect is responsible for making Venus the hottest planet in the solar system, even if it further than the Sun from Mercury. The Sun's solar energy is absorbed by Venus and re-radiated out into space. However the thick atmosphere on Venus traps this energy, raising the average surface emperature. It is so hot, in fact, that Venus would glow dimly red if one were standing on the surface.
Greenhouse Effect 
