Weather is temperature, precipitation (rain, hail, sleet and snow) and wind, which change hour by hour and day by day. Climate is the general long-term character of the weather and the nature of its variations that we experience over time. The Earth’s climate has changed on many timescales in response to natural factors. Over thousands of years we see the Earth move in and out of ice ages. At the other extreme, El Nino (variations in surface temperature of ocean water across the tropical eastern Pacific Ocean) come and go every few years, temporarily raising the Earth’s temperature. Over the course of the last century there has been an unusual increase in the average global temperature, accompanied by changes in extremes of weather. The term ‘climate change’ is often used to refer to changes to our climate arising from human activities.
Answered by the Met Office team, OPAL Climate Centre.