Maps show the number of feet tall a mountain and a city is above sea level.

If the same information was added to post codes, it would make everybody fully aware of the danger climate change has for us, and the importance of action to minimise it. Example: If York is 100 feet above sea level, my post code might be YO30 5ZQ100 and would change as the seas rise.

Do readers think this would be a good idea?

George Appleby, Leighton Croft, Clifton, York.