Climate research

The general effect has long been understood and it was common knowledge that the hole that remains has been a factor holding back warming. Concern about the hole in the ozone layer in the 1980s was emphatically not about preventing global warming, but about the effect of solar radiation on life on earth. Grasping this old story as an excuse to suggest the scientists don't know what they're doing irresponsible or just plain ignorant.

Further, you failed to understand the blunder in the IPCC report, which had falsely claimed the Himalayan glaciers could vanish by 2035. This claim came from one of three IPCC working groups, WG2, looking at impacts, adaptation and vulnerability. The science of climate change is dealt with by WG1. The glaciologists working for WG1 spotted the mistakes in the report, but their concern was not acted upon. However, these glaciologists have objected only to the timescales mentioned in the WG2 report. They were clear about the effect of global warming and the fact that glaciers are retreating.

It is therefore simply not true to say the scientific evidence has been called into question by this sorry episode. The IPCC's review process clearly needs overhauled, and its tin-eared approach to valid criticism is a concern. However, to claim the glaciers are not melting and that it's a "proven fact" that these two stories justify greater scepticism about global warming is breathtakingly wrong.

JAMES CHRISTIE

Dryburgh Crescent

Perth