If 'climate' and 'weather' are the same, why would there be two words?

Lots of people discuss 'climate change'.

What does the word 'climate' mean?

Climate is 'an average over 3 decades'.

For example .... rainfall in Ireland.

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

And another example - 'Average temperature 1951-1980'

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

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

Climate change means change in the 30-year average.

Not over a week, or a season.

But in recent times, global temperatures have changed quickly.

So it can be useful to look at single decades.

Data from the World Meteorological Organisation.