Conclusions

Correlation is not causation, but many, if not all, of man’s worst times since the last glacial maximum occur during colder and dryer periods. Often these times were made worse by warfare as in the Greek Dark Ages, the sacking of Rome, the collapse of the Akkadian Empire, etc. The colder and more arid climate could have been part of the cause of the wars. We go to war when we are starving and thirsty. More importantly, I was unable to find evidence of a crisis that was due to warming.

Given that man-made Carbon Dioxide is a very recent phenomenon, the radical climatic changes before 200 years ago cannot be attributed to man’s influence. They must be natural. The recent warming of 0.85°C from 1880 to 2012is pretty small compared to other temperature changes in the Holocene. It is clear from history that natural forces can cause significant climate changes. It is also clear that droughts are usually associated with colder periods, not warmer periods. Some climate changes are probably due to variations in the Earth’s orbit, but some might be due to variations in TSI (total solar irradiance) or other solar influences. How much is due to nature and how much is due to man is unknown.

Much of the last 18,000 years is characterized by more rapid sea-level rise than we see today. The current rise of sea level is very slow relative to the past and we are arguably more adaptable due to modern technology.

In the words of Professor Steven Mithen (page 507)

“The next century of human-made global warming is predicted to be far less extreme than that which occurred at 9600 BC [11,600 BP]. At the end of the Younger Dryas, mean global temperature had risen by 7°C in fifty years, whereas the predicted rise for the next hundred years is less than 3°C. The end of the last ice age led to a 120 meter increase in sea level, whereas that predicted for the next fifty years is a paltry 32 centimeters at most,…”