Warming to the evidence

In response to your correspondents (9 November), science is not democratic, nor ruled by apparent consensus. Rational people look at the evidence and form their own judgment. There is a spectrum of opinion in climate science, and it is unscientific for those in the mainstream to question the integrity of those they disagree with.

Iceland and Greenland were warmer 1,000 years ago than they are now. While carbon emissions rose in the 20th century, temperatures peaked in the 1930s, fell until the 1970s (giving rise to a "consensus" about global cooling) then rose again until 1998, since when there has been no upward trend.

There is nothing except circumstantial evidence to suggest that massive decarbonisation would enable us to tune the climate to our liking.

MARTIN LIVERMORE

Scientific Alliance

Cowley Road

Cambridge