[ExI] The causality analysis of climate change and large-scale human crisis

[Keith Henson]

One of the authors of this paper also wrote the one on wars in China
due to weather fluctuations.

Abstract

Recent studies have shown strong temporal correlations between
past climate changes and societal crises. However, the specific causal
mechanisms underlying this relation have not been addressed. We
explored quantitative responses of 14 fine-grained agro-ecological,
socioeconomic, and demographic variables to climate
fluctuations from A.D. 1500 to 1800 in Europe. Results show that
cooling from A.D.
1560–1660 caused successive agro-ecological, socioeconomic, and
demographic catastrophes, leading to the General Crisis of the Seventeenth
Century. We identified a set of causal linkages between
climate change and human crisis. Using temperature data and cli-
mate-driven economic variables, we simulated the alternation of
defined “golden” and “dark” ages in Europe and the Northern Hemi-
sphere during the past millennium. Our
findings indicate that climate change was the ultimate cause, and
climate-driven economic
downturn was the direct cause, of large-scale human crises in pre-
industrial Europe and the Northern Hemisphere.

https://www.pnas.org/content/pnas/early/2011/09/29/1104268108.full.pdf

It is amazing what we have learned about the past.

>From our viewpoint, the problem is that wars in response to bad
weather for the crops are about as inevitable as water flowing
downhill.

Bad weather straight to wars via famine.

Keith