§ Mr. BeardTo ask the Secretary of State for the Environment, Transport and the Regions what assessment he has made of the findings of current scientific evidence on the contributions to global warming of(a) the greenhouse effect, (b) sun spots and (c) other cyclical influences on climate. [141521]
§ Mr. MeacherRecent scientific results from the Hadley Centre have shown that the observed temperature rise over the last 50 years is most likely to have been caused by greenhouse gasses emitted through human activities. There is some evidence of solar effects causing warming in the early part of the century but these are now secondary to the effects of greenhouse gasses. Cyclical influences due to the earth's orbit are important on time scales of thousands of years but currently have a negligible influence on global warming.