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Who Bears Responsibility for Climate Change?

Duane Pendergast (04/01/26)  

Over the past century or two, scientists have noted that human use of fossil fuels could change the composition of the atmosphere by adding  carbon dioxide that results from burning it. They also noted that the increase could possibly lead to additional heating of the atmosphere by the sun. Over the last few decades it has become clear that the carbon dioxide content of earth’s atmosphere is indeed increasing. Over the past decade, it seems an increase in temperature has   been measured. So far it is very small, barely discernible in the “noise of day to day, season to season and year to year variations. 

Recently, many have read the work of those few dedicated scientists who study climate change.  They conclude the case has been made that humans are changing  the climate. They rush to blame this on the human discovery and use of fossil fuel and any other major energy source. They claim that, to save the world, we will have to sharply curtail energy use to reduce our emissions. The selfish so-called “developed” nations are the first to be blamed by these  purveyors of bad news.  Countries deemed to be “developing”, including long standing bastions of civilization such as China and India are deemed to be suffering deleterious climate change caused by the alleged excesses of Canada, the United States and others who have been early to harness earth’s stored energy for human use.  

I am weary of all the apologetic discussion associated with our use of energy for human benefit. Frankly, I like energy. So does almost everyone I know. It is the basis for the flourishing of humans on earth. I like our planes, trains, and automobiles. I like television and the Internet. I like to travel. I’m confident that the science and technology  that has brought us abundant energy, also provides the basis to come to understand and manage the impact it may have on climate. 

There are few better places for us to contemplate man’s impact on earth, than from the confines of an aircraft 40,000 feet above earth’s surface. From there, one can see that vast areas of the earth’s surface are under the control of humans. From that vantage point it is easy to reflect on human development of agriculture and the impact it may have had on earth’s  cycling of carbon through plant and animal life, soils and the atmosphere. The bit of history imparted to us in school, combined with a flight across Europe, India, China and Japan, reminds us those countries were  developed thousands of years ago. One wonders to what extent the development of agriculture there might have influenced forests and in turn the carbon cycle long before humans developed a thriving economy based on the recycling of Mother Nature’s store of fossil fuel. 

I am thus excited to see that see that at least one climate scientist, William Ruddiman, Professor Emeritus of Environmental Sciences at the University of Virginia, has completed a quantitative study of the impact of early agriculture on climate change.


Professor Ruddiman noted relatively recent anomalies in the record of cyclic variations of atmospheric methane and carbon dioxide from ice cores spanning hundreds of thousands of years. Beginning a few thousand years ago, coincident with the development of agriculture, the amount of these gases in the atmosphere tends to be higher than expected from earlier cycles. Professor Ruddiman goes on to study the effect of early agriculture activity in some detail. He finds that the associated clearing of forests and rice cultivation is likely an important factor in modifying atmospheric greenhouse gas content. He indicates early agriculture may have helped prevent glaciation in North eastern Canada and even suggests that the regrowth of forests initiated  by the depopulation attributed to bubonic plague played a role in the Little Ice Age (1300 to 1900 AD).  

Human use of fossil fuels and other forms of energy has greatly benefited us and associated ecosystems.  We have understood for a long time that it could affect climate through the release of greenhouse gases. Greater understanding and appreciation of the role humans have played through agriculture and forestry is needed if climate change proves to be a problem requiring modification of human behaviour to resolve. Professor Ruddiman’s paper may shift our thinking in that direction. So-called “developed” and “developing” countries need to recognize and accept responsibility for the roles they have played in the past.  Hopefully humans will work together to develop solutions to climate change which integrate human use of energy with their agricultural activity and the global carbon cycle.

Professor Ruddiman’s paper "When did Global Warming Start?" was published in Climatic Change, Volume 61, pp. 261-293 in 2003. It is available from Kluwer Academic Publishers.   Editorial comment on the paper by Thomas J. Cowley is freely available there.


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