Climate change is a long-term change in the statistical distribution of weather patterns over periods of time that range from decades to millions of years. It may be a change in the average weather conditions or a change in the distribution of weather events with respect to an average, for example, greater or fewer extreme weather events. Climate change may be limited to a specific region, or may occur across the whole Earth.

According to the National Oceanic and Atmospheric Administration (NOAA), there are 7 indicators that would be expected to increase in a warming world (and they are), and 3 indicators would be expected to decrease