Natural vs. Manmade climate change

I’m a believer that climate change is happening. I also believe that climate change is a natural process that has been happening for millions of years. On the other hand, the evidence seems clear that humans have recently caused it to occur much faster than what natural processes alone can explain.

Because of these beliefs, I joined the Mid-Ohio Valley Climate Action group last November. MOVCA is an “activist group” working to focus local attention on addressing the human causes of climate change through communication, education and social action. Because of my background as an engineer, plus as a statistician, MOVCA assigned me the task of developing a public opinion survey to gauge awareness and sentiment in our local area. Over the past six months we’ve gathered about 235 local responses to the survey which we modeled after one developed by Yale University in 2012. Yale together with George Mason University administered their survey nationwide to over 13,000 people and published their results in 2014.

The results from their survey and ours both indicate that most people believe as I do (about 80 percent). On the other hand, people disagree over how much of what we see and experience as climate change is natural, and how much is Manmade. Yes, there are those few who believe that climate change is: not happening, or is all natural or all manmade. And, people also disagree on what to do about it – which is unfortunate, because we either all succeed on this issue, or we all fail. The “doubters” and the “uninformed” can undo the efforts of the “believers” – globally.

I’m recently retired; so as an engineer, I’ve had the time to immerse myself in the science of climate for these past months. As a statistician, I’ve looked at charts and graphs all my adult life relating one variable against another, and am familiar with concepts of dependent versus independent variables, signal versus noise, correlation and significance, cause and effect, etc. And, here’s what I think I know.

First, there is a difference between climate and weather – weather changes hour by hour, while climate changes naturally century by century. Anyone who says, “it’s snowing, so much for global warming,” is mixing two very different subjects.

Second, the principal drivers of natural climate are changes in the Earth’s orbit and changes in the Earth on its axis. These changes go through natural cycles occurring over thousands of years. For example, they cause the resulting ice ages. There are other drivers (factors), but orbit and axis are the dominant ones.

Third, while changes in the Earth’s orbit and axis are the “drivers” of Natural Climate change, they are not the direct cause – they cause climate to change Indirectly. The direct cause is change in the concentration of CO2 (carbon dioxide) in the atmosphere. Atmospheric CO2 is kept in natural balance by natural processes. However, change in Earth orbit and axis causes that balance to readjust, releasing extra CO2 (primarily from the oceans). Atmospheric CO2 concentration increases causing the planet to warm and climate to change.

Fourth, now enters man into the equation, pumping CO2 into the atmosphere plus other gases which act the same as CO2. This comes mostly from our extraction and burning of fossil fuels.

Can you connect these four dots, and use them to draw a line to our likely, if not inevitable future? I hope, collectively, we can find the solution to this problem. While the cause seems clear and simple, the solution (what to do about it) is extremely complex and difficult.

David E. Ballantyne