Weather v. Climate

The daily high temperatures this month seem like they are riding a roller-coaster.   While these variations are par for the course in a transitional month like October, they often get people talking about the weather.  In listening to some of these conversations, however, I frequently hear the terms “weather” and “climate” confused.  To set the record straight, weather and climate are related, but different.  The main difference between the two is time.

Weather is the short-term state of the atmosphere at a particular time and place.  It references current local conditions like temperature, wind, and precipitation.  Driven mainly by the relative differences in temperature and air pressure from one location to the next, weather is constantly changing.

Climate is the long-term, ”normal” weather conditions of a given region.  It refers to the prevailing weather that we expect for particular seasons based on past experience and tends to be stable for the course of centuries.  Over extended periods of geologic time, however, climate does change. For example, our planet has seen the extremes of both ice ages with massive glaciers and warmer periods with higher sea levels.

While the Earth’s climate has changed a number of times throughout its long history, the changes happening today are occurring more quickly than they have in the past.  Experts say rising global temperatures – the result of increasing greenhouse gases in the atmosphere – are causing weather patterns to shift and, in turn, regional climates to change.