I was really amazed by the strong feelings stirred up by Sarah Clayton's letter criticising the Channel 4 programme The Great Global Warming Swindle.

This caused me to look a bit more deeply into that programme, and the whole debate.

So who is right and wrong?

Certainly, NASA, the United Nations (supported by the vast majority of the world's leading climate change scientists) and the EU all believe that the world has heated up considerably over the last two or three decades, and that the rise in temperatures is too great to be explained by natural changes.

They also believe there is a very strong link between these changes and the amount of pollution of all sorts that us humans chuck into the atmosphere.

On the other hand, there is a (much smaller) number of sceptics who think we are over-reacting to natural changes.

The Channel 4 programme tried to explain this, but rather shot itself in the foot by using distorted and out of date figures.

For example, the period of cooling between the 1940s and 1970s was apparently caused by sulphate pollutants which reflect sunlight.

Since clean air laws were introduced, some of this pollution has been cleared up - which gives us a more accurate picture.

Also, the link between solar activity and global warming is not clear cut.

The Channel 4 graph showing a close link between the two is quite simply wrong and out of date.

The corrected version of the graph shows no correlation between the data. There are a number of other errors which would take a very long letter to point out!.

So, what to think?

I'm no scientist so - like the vast majority of people - I rely on others.

Do I believe the UN, NASA and EU scientists, or a Channel 4 programme maker whose "facts" have been shown to be rather dodgy?

A no-brainer, I think.

The other issue is - shouldn't we in any case be doing all we can to reduce pollution and the waste of resources?

Some of the people supporting the Channel 4 view agree we should cut waste, and I for one am trying to cut my fuel bills through better insulation, turning off things when not used, and so on.

After all, it saves me money!

But it seems very sad that we are rushing to destroy the world's natural resources of oil and gas, which took hundreds of millions of years to create and which we will have used up within 200 years.

Perhaps we do need to regulate and tax in order to change people's behaviour, before it really is too late.

ED CRISWICK Chantry Hurst Epsom