Climate change is a long-term change in the statistical distribution of weather patterns over periods ranging from decades to millions of years.It may be a change in average weather conditions or the distribution of events around that average (e.g.,more or fewer extreme weather events).Climate change may be limited to a specific region or may occur across the whole Earth.
气候变化是从几十年到上百万年期间,气候模式的统计数据分布长期变化.气候变化可能发生于一般的气候条件下,也可能发生于该气候条件下的事件分布,（比如较多或较少的极端气候事件）.气候变化也可能局限于特定的地区,也可能发生在全球范围内.