What about
the role of carbon dioxide in climate? Al Gore did a great job to
dramatize the recurring glacial cycles in his widely acclaimed work of science
fiction. But he missed two inconvenient truths.
First, ice cores show that in the
glacial spring-time the temperature rose before the CO2 levels
rose. Therefore, the rising CO2 cannot be a cause of the
warming – it is a result of CO2 being expelled from the
warming oceans.
Second, at the top of every summertime
in the glacial cycle, the high levels of CO2 in the atmosphere were unable to
prevent the cooling into the next cycle of ice.
We are already in the autumn of the current glacial
cycle, and nothing man can do will change that. Global temperatures today
are lower than they were in Roman and medieval times. They will still
fluctuate with the effects of daily, lunar, yearly, and sun-spot cycles, but
the long-term trend of maximum and minimum temperatures will continue drifting
downward. Once summer temperatures in places like Siberia are unable to
melt last winter’s snow, the already growing glaciers will join to form ice sheets,
and Earth will once again be gripped by another long Glacial Winter.
The
transition from Greenhouse Earth to Icehouse Earth always occurs
suddenly. Once our verdant greenhouse is gone, life of Earth will never
be the same again.
The warm days, seasons, years, and epochs
have never been a deadly threat to life on Earth. Frost, snow, hail, and
ice are the killers. If our descendants do not have the energy,
resources, and wisdom to keep their people warm and fed through the coming
glacial epoch, humans may follow our Neanderthal cousins, who perished in the
last glacial winter, just 20,000 years ago.
It
is a wonder of the modern era that people who cannot accurately forecast next
weekend’s weather claim they can regulate the temperature of the whole globe by
bashing industry and taxing carbon.
There
is no evidence in climate history that carbon dioxide has a
detectable effect on global temperatures. However, if our continued use
of cheap, reliable hydrocarbon energy does slightly delay the onset of the next
glacial winter, we and all life on Earth should count ourselves extremely
lucky.
Viv Forbes is a
qualified geologist who has spent much of his life studying geological and
climate history as written in the rocks. He has also spent several years
in formal and private study of climatology and meteorology. He is the
founder of the Carbon Sense Coalition and a non-executive director of a small
Australian company developing a coking coal mine.
