Don’t be lulled

CLIMATE-change sceptics have seized on a leaked draft version of an IPCC (Intergovernmental Panel on Climate Change) report on the current rapid pace of ­global warming, focusing on a section concerning the hypothetical connection between the sun, galactic cosmic rays (GCRs), and global temperatures. (The report can be easily accessed by a brief internet search.)

According to this hypothesis, solar power drives the GCRs, which “seed” clouds, which have a cooling effect on the environment.

In short, increased solar activity produces a strong solar magnetic field which deflects GCRs away from Earth, hence less clouds and increased warming, while decreased solar activity has a cooling effect: more GCRs near Earth means more clouds, more reflected sunlight, thus more cooling.

Unfortunately for the sceptics, the IPCC report concludes this hypothesis is wrong. The sun does not drive global warming. 

Iain McConnell (Letters, 20 January) is one doubter who chooses, nevertheless, to blame the sun. In fact, the large body of peer-reviewed literature and data concludes that the sun has made little, if any, contribution to global warming over the past 50 years, so his assertion that “global climate has nothing to do with man but is simply based on sun changes” is hard to defend.

Mr McConnell has seized on ­reports of reduced sunspots as evidence of a cooling climate, but research has shown that, although declining solar activity (sunspots), combined with volcanic activity, has caused a slight cooling effect over the past three decades, this has not been enough to offset the inexorable rise in overall warming. 

I would ask climate-change sceptics to consider this simple fact: the destruction of rainforests accounts for roughly one fifth of recent human-produced carbon dioxide emissions.

Since the total amount of greenhouse gas we add to the atmosphere is more than 30 billion metric tonnes a year, and rising, this one ­example amply illustrates the impact just one of our ­activities has had on the planet.

Carolyn Taylor

Wellbank

Broughty Ferry, Dundee

AN EXCELLENT contribution from Iain J McConnell who points out that the “sun has gone to sleep” and this could result in global cooling. (Letters, 20 January).

Researchers say solar activity is a fraction of what they expect and conditions are “very similar” to those before the Maunder Minimum, a time in 1645 when a mini ice age hit, freezing over the River Thames.

Last year, Nasa warned “something unexpected” is happening on the sun and Richard Harrison at the Rutherford Appleton Laboratory in Oxfordshire told the BBC: “I’ve been a solar physicist for 30 years, and have never seen anything like this.”

The Space and Science Research Corporation revealed that of the 24 climate parameters it tracks, 18 now show global cooling as the dominant trend.

Cooling will be far worse than a few degrees of warming so we need to prepare reliable energy sources such as nuclear not unreliable wind turbines so we do not experience a “nuclear winter”.Global warming theorists who rely on computer models that have failed to predict the past 16 years are running out of excuses.

Clark Cross

Springfield Road

Linlithgow, West Lothian