Crew Commentary

Today’s Climate Change is all about People

Tim Rumage - Planetary Ethicist


While the new Director of the EPA may be confused about the role of human activity in climate change, the data and evidence are not. They clearly point the finger at humankind and our activities.


There are four types of greenhouse gases (GHGs) involved in climate change and global warming. They are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and fluorinated gases. In terms of volume, the ranking of highest emissions to the lowest is: CO2 > CH4 > N2O > Fluorinated Gases. In terms of Global Warming Potential (GWP) the ranking order is reversed: Fluorinated Gases > N2O > CH4 > CO2. One pound of a particular fluorinated gas (sulfur hexafluoride) captures as much heat as 11.4 tons of CO2.


Fluorinated gases are man-made chemicals. Nature does not create them. They are in the atmosphere contributing to global warming only because man produced them and released them (either intentionally or accidentally) into the atmosphere. From a climate change perspective, what matters is that they are in the atmosphere – not the how and why of their industrial production and use, nor the method of their release.


Currently the volume of CO2 released into the atmosphere surpasses the GWP of fluorinated gases. As of 3pm EST on March 11, 2017, more than 7.2 billion tons of CO2 had been released into the atmosphere this year. 


To help you visualize that number, put the image of a full-grown elephant in your mind. Now assume that elephant weighs four tons. To get 7.2 billion tons of full-grown elephants into the air by 3pm on March 11th, you would need to launch 303 elephants into the air per second, every second, since the beginning of the year. Do you think that 1,800,000,000 CO2 elephants floating over your head would not have an impact? Keep in mind; these are additional to the 200+ billion CO2 elephants that humankind has already added to the atmosphere (above natural levels) over the last few decades.


How do we know that we are responsible for those CO2 elephants? By looking closely at the CO2. There are three natural isotopes of carbon: Carbon-12, Carbon-13 and Carbon-14. The difference between them is the number of neutrons in the nucleus of the atom. So Carbon-14 has a higher atomic weight than Carbon-13, which has a higher atomic weight than Carbon-12.  


In climate issues, it is the ratio of Carbon-12 to Carbon-13 that tells the story. Plants and animals have more Carbon-12 and less Carbon-13 in their bodies than is found in the atmosphere. And fossil fuels, being derived from dead plants and animals, have more Carbon-12 and less Carbon-13. So, when fossil fuels are burned, they release more Carbon-12 than they do Carbon-13. When we see that the amount of Carbon-12 is increasing in the atmosphere relative to Carbon-13, then we know it’s the result of burning fossil fuels.


The Planet does not care how we feel about it or what we think of it.  The integrated systems that make Earth the only life-supporting planet that we currently know of, simply responds to what we do. When we increase the amount of heat trapping gases in the atmosphere, the atmosphere (where we live) gets hotter. 


Heat is a form of energy – the movement of atoms and molecules. The more heat there is, the faster atoms and molecules move. They become more kinetic. Heat is a transferable form of energy. Place a hot cup of coffee on a table, and the coffee cools as the heat (energy) is transferred to the atoms and molecules in the room. Temperature is the measure of the average kinetic energy of an object or substance. 


32OF is the freezing point and melting point of water. Slower moving molecules cause the water to freeze. Adding a little bit of heat makes the molecules move faster, which causes the ice to melt.


So as we increase heat capture by increasing GHGs, we experience rising temperatures, melting ice, warming oceans and more frequent forest fires. With more heat in the atmosphere, it contains more energy (and more water vapor) so we experience more frequent and more violent storms.


There’s no question that humanity is the cause of the rapid rate of climate change. The question is whether or not we are willing to work together (across party lines and the boundaries of counties, provinces, states and countries) to stop adding greenhouse gases to the atmosphere; and, therefore, to reduce the harmful impacts of a warming climate. It’s a simple question, with a difficult answer. Are we the parents of the future or the children of the past?