The atmosphere is probably the widely known Earth system. The atmosphere’s effect on our daily lives is obvious; it is where the weather happens. The atmosphere is also an important part of what makes Earth livable. It blocks some of the Sun’s dangerous rays from reaching Earth and traps in heat, making Earth a comfortable temperature. Additionally, the oxygen within our atmosphere is essential for life.


The term weather describes the state of the atmosphere at a given point in time and geographic location. Weather events do not occur at random but are dependent upon scientific principles and processes. Clouds, temperature, precipitation, winds and storms are dependent on interactions between global systems and local conditions such as geography, latitude, moisture levels and solar energy absorption.

Weather forecasts provide an estimate of the conditions we expect to experience in the near future and are based on statistical models of similar conditions from previous weather events. Temperature, amount and form of airborne moisture, cloudiness and strength of wind are all different components of our weather.

Weather can sometimes be confused with climate which refers to the “average” weather conditions for an area over a long period of time. The global change in climate has caused an in increase in cases of extreme weather. For example, the EPA reports that annual precipitation totals in the contiguous United States have risen 0.5 percent per decade since 1901. An increase in extreme weather events such as tornadoes, tropical storms, hurricanes, floods, lightning strikes, drought or cold can be harmful to life on the planet as well as the economy.