View source for Climate Change, War and Population Decline in Human History

'''* Article: Global climate change, war, and population decline in recent human history. By David D. Zhang , Peter Brecke, et al. PNAS, December 2007'''

URL = https://www.pnas.org/doi/10.1073/pnas.0703073104

"We show that long-term fluctuations of war frequency and population changes followed the cycles of temperature change."


=Description=

"Although scientists have warned of possible social perils resulting from climate change, the impacts of long-term climate change on social unrest and population collapse have not been quantitatively investigated. In this study, high-resolution paleo-climatic data have been used to explore at a macroscale the effects of climate change on the outbreak of war and population decline in the preindustrial era. We show that long-term fluctuations of war frequency and population changes followed the cycles of temperature change."


=Excerpt=

By David D. Zhang et al. :

"The hypothesis we propose posits that long-term climate change has significant direct effects on land-carrying capacity (as measured by agricultural production). Fluctuation of the carrying capacity in turn affects the food supply per capita. A shortage of food resources in populated areas increases the likelihood of armed conflicts, famines, and epidemics, events that thus reduce population size. As a feedback mechanism, population decline has a dominant tendency to increase the food supply per capita (seen in decreasing food prices), which results in relative peace and fast population growth. The interactions among these components in a social system create an important rhythm of macrohistory in agricultural societies."

[[Category:Civilizational_Analysis]]
[[Category:Thermodynamic_Efficiencies]]
[[Category:Articles]]