Wednesday, 2 December 2015

Irish Times - is it Global Cooling or Global Warming ?

"Most discoveries are made regularly every 15 years'' - The Doctor's Dilemma, Play by George Bernard Shaw. 

The threats posed by rising temperatures worldwide are no longer seen as theoretical, but real and already evident in Africa, south east Asia, the Arctic and elsewhere - Irish Times, November 2015.
The world's cooling climate is reverting to conditions prevalent between 1600 and 1850 - Irish Times, May 1976 

By 1976, science had put 12 men on the moon and Richard Dawkins had just published, The Selfish Gene, an incredible analysis of genetics and the role of evolution in it.  The reason I state this is to show that science was at an advanced stage at this time. So the fact that there was consensus that the world was cooling at the time should carry alot of weight. However, the cooling at the time was mistaken for a long term trend when in fact the world slowly began to warm not long after the publication of "Global Cooling" articles such as the below in 1975 and 1976.

We can see the cycle of the Atlantic Multidecadal Oscillation (AMO) below and how concern about global cooling or warming have occurred in the period with the respective temperature variances  : 

The overall temperature trend in the past few hundred years, however, has been one of warming :

The above graph was produced from 14 separate global temperature proxies (sediments, boreholes, pollen, oxygen-18, stalagmites, magnesium to calcium ratios, algae, cave formation, etc. over a wide geographical range) and shows a warming trend starting around 1700, with warming  and cooling periods about the trend.  It is a remarkably accurate graph considering it was not produced from direct temperature readings. We can see that in the 5th century, the climate was getting warmer. This explains how Irish monks could live on Skellig Island off the coast of Kerry until circa 12th century, when temperatures were similar to what we have today. 

It also explains how St.Brendan made his voyage around the Atlantic about the same time and that Tim Severn's re-creation in the 1970s was indeed made under colder conditions. It explains the Vikings invasions of Greenland and Iceland. The pre-1700 Little Ice Age is also there.

So the climate began warming up circa 1700, long before man made carbon emissions and it's just aswell it did as nobody would have liked to have lived through another ice age. Going back to Dawkins, we know that humans evolved to adapt over short term climatic conditions and we are therefore blind to the overall trend lasting over hundreds and thousands of years.

The articles below, from the Irish Times in the mid-70s, shows we should not be confident about predicting the future climate. Of course, controlling pollution (a separate issue) is something which we do need to do something about. But our government seems to think (aswell as most of the political class) that building more industrial wind turbines will somehow sort out the main polluting sectors in Ireland - that of transport, heating and agriculture.

1 comment:

  1. It's strange how ordinary people fear the cold and love the heat, while greens, eco warriors and taxation enthusiasts fear the heat and love the cold. Yet taxes on home heating fuel cannot be collected in hot weather. The suffering caused from being too cold is much more awful than enduring a hot day. The cost of salting roads, snow ploughs and rescue is limited to very cold periods. Few crops will grow in winter, Very strange.