I disagree with Philip Roe that climate change is a natural, cyclic occurrence that somehow has nothing to do with man's environmental activities (Letters, September 8).

I draw Mr Roe's attention to the fact that the year 1998 stands as the hottest year since the instrumental temperature record began (which was in the mid-1800s!).

There is, unfortunately, no way on earth this can be down to natural, cyclic occurrence, because only abnormal influences can properly explain such a rapid and unprecendented increase in global mean-surface temperatures.

All the global warming effects are due to man-made pollutants in the air, specifically massive quantities of carbon dioxide (CO2) through the burning of fossil fuels. Of that there is no possible doubt. As though releasing seven billion metric tonnes of CO2 a year couldn't influence our fragile climate!

An increasing number of natural disasters (Hurricane Katrina, for example), strange changes to wildlife (animals shifting their ranges poleward) and dramatic polar events (pieces of ice the size of Jamaica breaking off and melting) make it crystal clear that man-made climate change is really happening.

Aled Jones,

Mount Crescent,

Bridlington,

East Yorkshire.

Updated: 11:02 Friday, September 09, 2005