From a small northwestern observatory…

To give credit right up front where credit is due, today’s post was stimulated in no small part by an excellent piece written for NPR last month by Angus Chen titled 1,000 Years Ago, Corn Made This Society Big.  Then, A Changing Climate Destroyed It.

In “all my spare time”, I’ve wondered a bit about the dichotomy of North American natives versus Europeans.  The latter developed a relatively advanced society by the time of Columbus, while the former seemed to be living in the bronze age.  I’ve really not had the time, effort, or inclination to study it much, and the few pieces I’ve read didn’t seem to be very robust, from a scholarship perspective.  One stream of research notes that pre-Columbian Europe, in the crossroads of trade among three continents, had more complex influences.  However, North American tribes traded among themselves, and before the Europeans brought gifts of small pox and syphilis, the population of this continent was certainly at a critical mass.

One of the less convincing arguments stemmed from lack of wheat.  In short, a population needs a robust agriculture in order to sustain modern civilization.  One farmer needs to be able to feed more than him or herself.  To me, this was also suspect — I’d been taught as a grade schooler that east coast natives actually demonstrated advanced cultivation techniques to European immigrants.  Chen’s article turns all this on its head by noting the Mississippian American Indian culture, a group of farming societies ranging from north of St. Louis down to present day Louisiana and Georgia.  The most prominent of these was the city of Cahokia, about 15 miles east of present-day St. Louis.  Around the 9th and 10th centuries AD, this society was fairly robust and successful, with large cities, complex agriculture, and trade.  In the absence of wheat, their principle row crop was corn, and apparently this contributed their diets in the same way wheat contributed to Europeans.

However, by the time Europeans came in the 15th century, these cities had already been abandoned.  Modern research now pins the failure of this civilized society on climate change.  The rains which sustained the corn crops for hundreds of years dried up, and by 1350 AD the region faced profound drought that lasted up to 500 years.

Climate change and crop failures led to destabilization of society and government.  Current archeology points to construction of palisades, burned villages, and skeletal injuries consistent with warfare beginning around 1250 AD.  Scientists are reluctant to blame the  entire collapse on climate change, but rather that climate change was probably one of a series of problems that brought down this remarkable American civilization.

The vast majority of scientists today concur that climate change is real.  Something on the order of 97% of recently published peer-reviewed empirical studies support this.  Admittedly, there is less concurrence regarding the impact of human factors, such as CO2 emissions, but the majority of scientists still seem to agree that at the very least, human intervention has probably accelerated existing trends.  That said, speaking as an economist, this all has implications for societal change which must be addressed in an organized, cogent manner.