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Thursday, October 25, 2018

The End of the Ice Age

Sorry to rain on your parade but it ain't over.  We are still in the middle of an Ice Age.  It has been going on for about 2.8million years and is not over.  It is actually, if named  correctly, an epoch.  Namely the Pleistocene Epoch.  This Epoch is colloquially called the Ice Age.

During the Pleistocene Epoch (Ice Age)  there have been many icy periods (Glacials or glacial periods) and relatively ice free periods (Interglacials or Interglacial periods).  We are at present in the Holocene Interglacial and the previous one around 125,000 years ago was the Eemian Interglacial. Between the Eemian and the Holocene Interglacials was a glacial period in which glaciers extended from the Arctic to a bit past the American Canadian border. You could say that the Holocene Interglacial started 20,000 years ago since that was the peak of the previous Glaciation but melting really got underway a little less than 12,000 years ago so that is usually taken as the beginning of the Holocene Interglacial.

We should already be beginning our slide into the next Glacial period (not Ice Age - remember, we are still in an ice age) but the plow, rice paddies and the destruction of forests slowed our slide into the next galcial just long enough for the Industrial revolution to kick in and send us into a warming phase.  Read Plows, Plagues and Petroleum by Ruddiman for chapter and verse on the plow, plagues and rice paddies.  Despite early (from about 8000 years ago) human influence delaying our slide into the next glaciation, we apparently were finally just starting into the next glacial period when the industrial revolution reversed the trend.

The final straw in our slide into the next Glacial was the demise of the population of North America due to European diseases and the black death in the 'Old world'  Both resulted in forests regrowing and the sucking down of Carbon dioxide just enough to start the accumulation of snow way up on the high lands of Baffin Island.  Apparently there is still a halo of dead lichens around this area where the expanding permanent ice and snow killed the lichen.  Green house gases then increased enough to reverse the accumulation of snow.

Some scientists are predicting that we are going into a sort of Maunder Minimum in which sun activity decreases.  No way, though, that this will reverse our warming.  We have put way too much Carbon dioxide into the atmosphere.

Our output of green house gases, by the by, long before the industrial revolution, is the explanation of why this interglacial has been so much more stable, weather wise, than previous interglacials.

With our output of Green House Gases and especially Carbon dioxide, we have put off the next glacial and with a little luck we may put it off until the next Interglacial.

However, we now have too much of a good thing and it is time to put carbon back into the soil, into trees and to stop adding more to our atmosphere.  We have the technology.  Any reasonably bright year 12 student could tell the politicians exactly what they should be doing but the politician won't listen.  They want to be elected next time and need the money from the vested interests to succeed.  Until we make it illegal for anyone to contribute anything to any politician for any reason whatsoever, we will be pushing the brown stuff uphill with a spoon.  Never was the old adage, Who Pays the Piper Calls the Tune more true.

One of the barriers to the use of renewable energy is it's unpredictability.  In the long term, you know more or less how much wind and sunshine you will get at any location but it comes in unpredictable booms and busts.  There are may fixes including notably,  demand balancing of our grids (electricity priced to reflect the extent of availability over  demand and devices that use electricity selectively when it is most available and hence least expensive).  However, a really good battery for stationary applications would go a long way to help.  Fortunately there are technologies in the wings, which could fill in the gaps left by other methods and systems.  There are Vanadium and Iron flow Batteries,  Liquid metal batteries and  the Zinc bromide flow and gel batteries.

It looks like we are over the hump.  Tesla sold a mega battery to a wind farm in Australia.  What is particularly significant is that it is on track to produce revenue equal to a third of it's capital cost by the end of the first year of operation.  Economics trumps all other motivations.  This could be even better if the alternate battery technologies take off and become less expensive than Li batteries.

You might ask yourself, why I get so up tight over terminology - namely the misuse of the term Ice Age.    You will see in the popular literature and even in scientific papers, the use of the term Ice age to mean the glacial period between the present Holocene interglacial and the previous Eemian interglacial.  Why is this important.  We as humans are prone to lie to ourselves.  For instance, we note that the megafauna of North America disappeared when the Ice Age ended.  And we admit that man might have had something to do with it but it was probably climate change.  Nonsense.

First, as I said, we are still in an Ice age.   (The Pleistocene Epoch to be totally correct) so it hasn't ended.  But that is the least of the deception.  The Mega Fauna survived repeated cycles of glacials and interglacial and depending on how you define them, there have been between 30 and 50 such cycles within the present ice age (Pleistocene epoch).

No, the NA mega fauna disappeared at the end of the most recent Glacial period.  They survived quite happily the end of many previous Glacials and the subsequent interglacial and only the recent one caused their demise.  The only difference was the arrival of the first people who ate their way through these animals from one end of the Americas to the other.  If you don't think that primitive hunters could wipe out the mega fauna of the Americas, just look at the extinctions in Australia (50,000 years ago) and New Zealand (700 years ago) or in  any other  area when man first arrived.   Now we are finishing the job with habitat destruction.  Soon we will be alone in the world and then pooooof.   We are Gone Burgers. Evolution can begin again from whatever remnants remain.

ps.  Note that there are indications that around 12,000 years ago, there was a major meteorite hit on North America which left a layer of sediment recording it's existance.  This could have had an effect on the fauna of North America but there would only need to be a few 'refugia' left for the animals to make a come back.  Future work may shed more light on this possibility.

The Anthropocene actually started at different times in different locations with the arrival of man.  So much for first people being the guardians of nature.  In actual fact, they eliminated any animal that they could hunt faster than it could reproduce. Now modern man is finishing the job.

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