Climate change is a change in the statistical distribution of
weather patterns when that change lasts for an extended period of time (i.e., decades to millions of years). Climate change may refer to a change in average weather conditions, or in the time variation of weather around longer-term average conditions (i.e., more or fewer
extreme weather events). Climate change is caused by factors such as processes, variations in
solar radiation received by Earth,
plate tectonics, and
volcanic eruptions. Certain human activities have also been identified as significant causes of recent climate change, often referred to as "
global warming".