COME ON, Christian Vassie (Letters, January 1) – let’s get real!

To the best of my knowledge, all coal mined on this earth contains the isotope carbon 14. To use your own favourite phrase, “by definition” according to carbon dating theory coal cannot be millions of years old because carbon 14 has a half life of 5,700 years.

When the coal measures were laid down, atmospheric CO2 was at least 30 times its current level. So to replenish the depleted forests we need to increase the levels of CO2, plus the fact that increased temperature and rainfall will also help to achieve this.

Ken Barnes, NorthView, Catterton, Tadcaster.