All four regular readers of this blog (Hi Mom!) are no doubt aware of my occasional consternation with Benny Peiser and his bollocksed-up reading of climate science. But despite that, I’ve been an enthusiastic consumer of Benny’s CCNet for years. I started reading it when I was writing a lot about near-earth objects – asteroids and the like – and very much in the thrall of the journalistic opportunities offered by the “Holy shit, we’re all going to die!” school of NEO thought. The range of discussion on CCNet has long been helpful in calming my journalistic impulses in that regard.
On climate, I think Benny has earned his critics’ scorn because of his enthusiasm for outliers in the face of a broad consensus about key questions about current and future climate. So I generally treat his posts on climate science as a quick way to track the outliers on one fringe and don’t pay too much attention, aside from the occasions when my annoyance, against my better judgment, boils over.
But one of the problems in the climate wars is the scientized way we all argue about the climate science while spending little time on the rather intricate questions of societal effects. Both sides have their views on this, but the discussion is engaged very little. That’s the set of questions on which Benny’s contribution is of great value to me – the questions of what impact climate variability and change had in the past on human societies and might in the future. I’m interested in this, because drought (variability) has been a defining characteristic of the development of human societies where I live. In that regard, Benny’s posted a couple of noteworthy items recently
The first is a link to a paper by Petra Dark on the effect of climate change circa 850 BC on settlement patterns in Britain.
Climate deterioration at around the time of the Bronze Age/Iron Age transition has for long been argued to have resulted in upland abandonment in northern and western Britain, and recent research has provided evidence that a major climate downturn from 850 cal BC caused settlement abandonment in western Europe and potentially worldwide. It is, however, unclear to what extent only ‘marginal’ sites were affected, due to the lack of any systematic attempt to view the evidence for settlement and land-use change across a range of landscape types with differing sensitivities to environmental change. This paper addresses this issue by an evaluation of 75 pollen sequences spanning the late Bronze Age and early Iron Age in Britain to assess whether climatic deterioration was sufficient to cause widespread land abandonment. The results provide no evidence for wholesale land-use change at this time; the overall picture is one of continuity of land use or even increased agricultural activity.
(If you don’t have library access, Benny’s posted a lengthy excerpt on CCNet.)
Back on April 3, Benny highlighted a paper on a similar theme by Nick Brooks, which argued that rather than causing societal collapses, climatic change leads to increasing societal complexity and technological advance:
There is direct evidence of adaptation to increased aridity in the archaeological literature relating to the Sahara and Egypt. In the other regions examined, the data are consistent with the notion that increased social complexity was largely driven by environmental deterioration, although further local-scale archaeological and palaeoenvironmental data are required to clarify the processes involved.
This last point is a case that can be interestingly argued here in the southwest, where a number of researchers have argued (persuasively, I think) that climate change played a role in the termination of the classic Anasazi. The question here is whether one ought to call that a “collapse,” or whether their departure from the San Juan Basin might rather be considered a migration and adaptation, with a resulting society that was more robust to climate change. A similar argument can be made (thought I’m less familiar with the details) for the termination of the classic Maya.