What is climate? What is the climate system? What is climate change?

Climate: Different from weather, climate refers to the average or statistical state of meteorological elements (such as temperature, precipitation, wind, etc.). ) and long-term (month, season, year, year to hundreds of years or longer) weather phenomena mainly reflect the basic characteristics of a certain area, such as cold, warm, dry, wet, etc., and are usually characterized by the average value of a certain period and the deviation value from the average value (called anomaly value in meteorology).

Climate system: it is a unified physical system including atmosphere, hydrosphere, land surface, cryosphere and biosphere, which can determine the formation, distribution and change of climate.

Climate change: in the history of the earth, the climate is constantly changing, but the speed of this change is generally slow, and natural creatures adapt to this change through their own adjustment and evolution. However, since the industrial revolution, due to human activities, mainly burning a lot of fossil fuels and emitting a lot of greenhouse gases, the concentration of greenhouse gases in the atmosphere has risen sharply, which has led to the enhancement of global greenhouse effect and may cause global climate change. Therefore, in the United Nations Framework Convention on Climate Change, climate change is defined as: climate change caused by direct or indirect human activities that change the composition of the global atmosphere, that is, climate change that exceeds the natural climate variability observed in a comparable time period.

(Quoted from China Climate Change Network)