Most climate change scientists will agree that one of the biggest factors effecting the phenomenon is carbon dioxide emissions, which have jumped significantly since the beginning of the Industrial Age about 200 years ago. Our main energy sources remain much the same as they were back then, fossil fuels, including coal and petroleum. While some major forms of pollution, such as nitrous oxides and soot, have nearly been eliminated, there still remains the carbon dioxide emitted when these fuels burn.
True, there are renewable resources that are in the mix, but for the most part, everything from lawnmowers to power plants is powered in some way by fossil fuels. The increase of industrialization has led to a corresponding increase in carbon dioxide emissions, a major greenhouse gas. Greenhouse gases trap heat in the atmosphere instead of letting it radiate into space, and thus we are in the throes of climate change.
The Dean of Duke University’s Nicholas School of the Environment, Bill Chameides, thinks that the answer is more complicated than just carbon dioxide emissions. In an article posted in Huffington Post Green pages, Dean Chameides takes a look at the heat we as a species produce in all of our activities. Add this to the energy that the earth absorbs from the sun, and our carbon dioxide emissions, and the result is the climate change that we are experiencing all around us.
True, our activities are pretty small, but like the straw that broke the camel’s back, it has an effect. Take for example, energy input from the sun, averaging 174PWh [Petawatt-hours], or 174,000,000,000,000,000,000 watts per hour, of which about 90PWh reaches the earth’s surface, about 32,850PWh annually. The greenhouse effect is estimated at about 1PWh annually and global energy use was 20PWh in 2008. Global energy use is increasing, but still not anywhere near what the earth gets from the sun.
Still, Dean Chameides’ concern is that climate change scientists might not be taking our own energy use into account. He points to the laws of thermodynamics, the first of which, the law of conservation, states that energy never disappears, but can be converted into other forms. The second law, the law of thermodynamic equilibrium, infers that eventually all forms of energy eventually are converted into the most random form of energy, heat.
No matter what we do, from turning on a stove, an obvious heat source, or starting an electric motor, a not-so-obvious heat source, according to Dean Chameides, it all ends up as heat energy. If we consumed 20PWh in 2008, the law of conservation dictates that we generated 20PWh of heat energy. Is it significant? Perhaps not, but it is part of a very complicated equation pitting humankind against the planet. Climate change is much more complicated than simple carbon emissions.