Jy blaai in die argief vir history.

Climate Change: The debate in Geobulletin (resumed)

28/01/2013 in Uncategorized

Anna het oor die naweek in die Kaap gekuier en is op pad terug op die Interkaap-bus, trek nou seker al verby Springbok. Soos ‘n groot hond is ek geneig om so vas te slaap dat ‘n wekker of selfoon-oproep my nie sommer sal steur nie. Terwyl ek nou wakker is is dit ‘n goeie geleentheid om te blog, terwyl normale mense nog slaap.

Ek het in ‘n reeks poste berig oor ‘n debat in die “Geobulletin”, kwartaalblad van die Geologiese Vereniging van S.A., oor klimaatsverandering. Dit het in die Desember-uitgawe begin met ‘n brief deur Rose Prevec wat meen “deniers” hoort nie in die debat nie. In die Maart-uitgawe het John Trusswell (skrywer van universiteitshandboeke oor geologie) en ek (word genoem in “A Century of Geological Endeavour in Southern Africa, 1895-1995”), haar standpunt aangeval. Sy het repliek gelewer in die Junie-uitgawe, waarop my en John Trusswell se replieke in September geplaas is. In September was daar ook ‘n bydrae deur emeritus-professor John Geissman (VSA) en ‘n verwysing deur die redakteur van “Geobulletin” -albei glo in AGW. In die Desember 2012-uitgawe lees die laaste paragraaf in ‘from the editor’s desk’ soos volg:

“The ongoing saga of the threat that climate change poses to our earthly paradise is continued in another letter from Deon le Roux and in an article from William McClenney. Both contributions question the role of carbon dioxide as a cause of climate change, and are rather technical. However they highlight the dangers of thinking that the causes of climate change are easily understood.”

Ek wil lesers nie verveel met holrug-geryde argumente oor die aangeleentheid nie. William McClenney, “a California Licensed Professional Geologist and Registered Environmental Assessor” se artikel verskaf egter data wat minder algemeen bekend is en word hier in aflewerings geplaas.

Climate Change – The Short Story

In some ways, I applaud the sense of urgency that accompanies the perceived need to do something to affect climate change. The need is there in more ways than you presently know. But the means could be another matter entirely.

The Akkadian Empire under Sargon (2,300-2,200 BC), mankind’s first empire ever, succumbed to climate change that happened rather suddenly. A 300 year long period of drought struck this nascent civilization and toppled what turned out to be only a 100 year empire. The Old Kingdom of Egypt and the Harappans of the Indus Valley suffered a similar fate 4.200 years ago, succumbing to an abrupt drought that ended those civilizations, with Egyptians “forced to commit unheard of atrocities such as eating their own children and violating the sacred sancity of their own dead (Fekri Hassan, 2001)”.  The Mayans had pretty much the same luck with three periods of extreme drought at 810, 860 and 910 AD. Sadly just two years after the last drought, which saw 95% of the Mayan population gone, wet years returned to the Yucatan.

(to be continued)