Weather and climate
To understand what climate change is, we have to appreciate the difference between weather and climate. "Weather" changes constantly and relates to the local temperatures, winds and precipitation (rain, hail, sleet and snow) that we experience every day. "Climate" refers to the patterns (over long periods of time, typically 30 years) of average weather and its variations and extremes across different regions of the earth.
Changes in climate
The earth's climate has changed many times in response to natural causes. These include interactions between the oceans and the atmosphere, changes in the earth's orbit and volcanic eruptions. Use of the term "climate change" now usually refers to changes which have happened since the early 1900s when the climatic effects of the the global industrialisation of human society began to be seen.
A Climate Change Strategy and Action Plan for Wigan Borough is available.