SCIENTISTS at the Climatic Research Unit at the University of East Anglia would not disclose either their raw data of world temperatures or the computer programs used to produce their predictions.

After the most recent cool period (which ended around 1975), carbon dioxide levels and temperatures did rise together, giving some credibility to the unproven theory that increased carbon dioxide was causing the increased temperature.

Before that, scientists thought that the world was entering a new ice age. Some of the same people have since been the keenest advocates of global warming.

The emails leaked from the CRU show scientists worldwide trying to cover up the fact that the temperature was no longer rising in line with their predictions.

One email mentioned the need to "hide the decline".

Even Professor Phil Jones, presently suspended from the unit over the "Climategate" emails, admits that there has been no statistically significant rise in world temperature since 1995 although carbon dioxide continued to increase during this time.

Fifteen years is long enough to qualify as an indicator of "climate" rather than just "weather" (John Davis March 4).

So either carbon dioxide is not driving temperature increase significantly or something more powerful (possibly the sun's activity) is overriding it.

Carbon dioxide is a beneficial, life-giving gas which promotes plant growth.

Mr Davis is, of course, quite right that more thrifty, efficient use of fuels is desirable. But there is no need to panic and the ridiculous system of carbon quotas and taxation is simply an EU/government wheeze to tax us all more heavily.

Edward Spalton,

Sutton Lane,

Etwall.