What does 'climate' actually mean?

Lots of people discuss 'climate change'.

 What does the word 'climate' mean?

Folks forget how climate is defined.....

Climate is normally defined as 'an average over 3 conventional decades'.

A conventional decade is, for example, 2001-2010, or 1961-1970.

So ..... 3 full, conventional decades......such as 1981 to 2010.

For example .... rainfall in Ireland.


And another example - 'Average temperature 1951-1980'

The definition of 'climate' goes back at least 100 years.

So if we are discussing climate change, that is what 'climate' means.

But in recent times, there has been a lot of variation in global temperatures.

So it can be useful to look at single conventional decades.




Data from the World Meteorological Organisation.

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