Calculating the Ice Ages and modelling Plate Tectonics

7 May 2014

At ... for May 5th, we have a couple of stories of interest. If there was not Plate Tectonics, we are informed, life may not have evolved. Astronomers at the Smithsonian Centre for Astrophysics say also that if the Earth was smaller and less massive there would have been no tectonics - or continental drift, or any of the nice bits of uniformitarian consensus earth science. No way to build mountains, for example - assumed to be as a result of Plate Tectonics.

Is this a kind of riposte to the Expanding Earth hypothesis? If is has expanded it must have been smaller and if there is life it could not have been smaller - or some kind of logic like that. Needless to say the claims result from modelling and computer simulation - which all depends on what they factored into their model (and what they might have left out). CAGW theory was of course a prerequisit component of the model as we are informed carbon dioxide acts as a thermostat - not the water in the oceans and in the atmosphere.

However, the study does include a bit of catastrophism - but suitably dated long ago, over 3 billion years ago to be precise. An impact or impacts were necessary in order to get Plate Tectonics in motion - but no such evidence for the impact can be found as the rocks would be so old they would have subducted in the course of time.

The online journal Nature Communications, a unformitarian organ, claims climate change during the Ice Age tallies with orbital changes of the Milankovitch kind - thereby stoutly defending their batting crease. The new study says temperature fluctuations and the agrowth and decline of pluvial lakes in the Great Basin correspond with orbital changes (23,000, 45,000 and 100,000 year cycles). Rather than use data which relies on dating estimates from rates of compaction as in ice cores, they say they have used, instead, stalagmite based record (which presumably relies on an estimate of stalagmite rate of growth). Oh well, it is said to agree closely with foraminifera in deep sea sediment cores - and yet these have a question mark hanging around them too. What they are saying, in one way, is that ice cores are unreliable - but we will use unreliable foraminifera oxygen isotopes as a matter of faith.

They used stalagmites from caves in Nevada and used this to compare with a speleotherm based climate record from elsewhere - which used uranium isotopes which were then compared to the oxygen isotopes of foraminifera shell accumulations in the oceans. The pluvial lakes of the Great Basin will reappear in 55,000 years time we are confidently informed - but who is going to be around to know. They also say they can see evidence that the Great Basin has been warming over the last 1600 years (from AD400) - which must be news to climate scientists of various persuasions. They attribute this to human influence in the region - camp fires in the desert perhaps. If they had said 160 years - from 1850AD, it might have been a trifle more believable - but can speleotherms be so exact, in 100s rather than 1000s of years?