Climate warming created farming
By Dennis T. Avery
A new study by Dr. Shahal Abbo of Israel says the invention of farming wasn't due to climate change because farming depends on a relatively stable climate. Dr. Abbo isn't looking at the picture broadly enough. .
The ice cores tell us the invention of farming came about not long after the end of the last Ice Age, one of the earth's key climate changes. Modern Homo sapiens had been around for over 100,000 years—but we've found no evidence of farming until after the last big ice sheets melted about 10,700 years ago
Before then, humans had been stealing birds' eggs, digging clams, gathering seeds and picking berries. Stone Age man also learned that his hunting bands could drive big carnivores away from their kills with stone-tipped spears, then feasting on meat they couldn't catch themselves.
Wondrously, the ice disappeared. The earth's climate warmed more than 10 degrees C. Chicago, for example, shifted from mile-thick glacier to sunny Corn Belt. That's certainly climate change in my book. And since the big ice sheets have been gone, the earth's climate has indeed been relatively stable.
Mostly, the temperatures over the last ten millennia have ranged up and down about 2–4 degrees C at the latitude of Paris or Washington. The major variations have been the moderate 1,500-year Dansgaard-Oeschger climate cycles documented in the ice layers and seabed sediments. Our Modern Warming is apparently the sixth such warming cycle in 10,000 years. The warmest of the recent warming cycles began 9,000 years ago, and was 2.5 degrees warmer than today.
Humans probably continued their traditional hunting and gathering in the first years after the ice receded. But in the Middle East of 9,000 years ago, the Stone Age hunters apparently began to notice recurring seasonal crops of wild cereals. At first, they probably gathered some of the grain to eat, and perhaps some more to lure sheep near enough for killing.
But as human numbers expanded under the basking sun, there may not always have been enough wild game in the Judean hills to feed everybody. The idea of deliberately planting more of the cereal seeds, domesticating livestock and shifting their diets more heavily to grain would gradually have become attractive. And, humans of 10,000 years ago were fully as intelligent, curious, and anxious to survive as we are today.
Once the idea of controlling food production ignited, the rest is history. Farmers have taken over every part of the world that can readily grow crops, and even some difficult eco-systems that are right on the margin, such as Asia's terraced mountainside rice paddies.
Many alarmists have warned that today's "unprecedented warming" would bring poorer crop yields. However, a Chinese research team reported recently in Climate Research that China's food production has increased during the Modern Warming. Credit for the food production gains goes both to the longer, warmer growing seasons—and to the fertilization effect of higher CO2 levels have on crop plants. Higher CO2 levels both stimulate crop growth and increase the plants' water use efficiency.
Chinese rice and wheat production have expanded north with the 1.1 degree warming of the past 50 years, displacing lower-yield short-season crops. In addition, the extended growing seasons have permitted higher cropping intensities: three crops in two years for many areas where before there was only annual cropping.
Logic should have told us to expect this increased food production—but logic has been in short supply among the global warming alarmists.
Dennis T. Avery is a senior fellow for the Hudson Institute in Washington, DC. He is an environmental economist and was formerly a senior analyst for the Department of State. He is co-author, with S. Fred Singer, of Unstoppable Global Warming Every 1500 Hundred Years, Readers may write him at PO Box 202, Churchville, VA 24421 or email to firstname.lastname@example.org.
Get weekly updates about new issues of ESR!