Earth’s Climate is Always Changing

Visualization depicting specific atmospheric humidity on June 17, 1993, during the Great Flood that hit the Midwestern United States. Source: NASA Center for Climate Simulation: Data Supporting Science

Our atmosphere is a highly variable system that changes over a range of different times (hours, days, weeks, months and years) and distances. Even small scale variations in circulation patterns can cause changes in the climate - especially temperature and precipitation. Remember that climate describes the long-term conditions. Variations in local climate are common from year to year, but climate looks at the big picture over longer periods of time.