3 Causes for concern

The increased greenhouse effect due to human activity is called the anthropogenic greenhouse effect (sometimes called the enhanced greenhouse effect) to distinguish it from the natural effect discussed earlier. The effect on the Earth is very much as though the output of the energy from the Sun has increased. This increases the mean surface temperature of the Earth, often referred to as global warming, which then causes other changes to our climate. These include an increase in the number of extreme weather events.