I have been involved with science communication and education for the majority of my adulthood. The array of venues in which I have taught, subjects I have conveyed, and audiences I have engaged has been vast; each delicate combination of venue, subject, and audience throwing a delightful challenge my way. In a non-native tongue, I have explained the wonders of photosynthesis to disinterested German schoolchildren in the middle of a Saxon forest. I have performed freestyles about magma to convince dozens of Detroit pre-teens why I was marginally different from other fluffy, pontificating snow-white Teachers for America. I have taken tipsy corporate adults at company holiday parties on journeys through electromagnetism at the Museum of Science in Boston. Surprisingly (or not), this looks quite similar to the electromagnetic journey on which I take sober third-graders. Physics, chemistry, biology, geology. Libraries, natural spaces, museums, classrooms, summer camps. Babies, children, teens, adults. You name the combo, and I’ll pull out my bag of tricks, outfitted with analogies, props, demonstrations, deep questions, lesson plans, relevance, and utter enthusiasm. Not to toot my own horn, but somebody once said that I was “like Miss Frizzle, but with more street cred.”
So why do I have such a difficult time explaining climate change to my own mother?
Well, dear reader, if you are like me, you may have become embroiled in friendly debate with close relatives and acquaintances around this weighty and newsworthy issue. However, if you are also like me—i.e. not a practicing climate scientist—the challenge of explaining and understanding the various nuances of climate science can become a tangled mess pretty quickly, especially at a venue like the Thanksgiving table. Climate science features complicated scientific principles: lagging thresholds , energy conservation, systems, cause and effect, and averages over long periods of time, all wrapped in statistical uncertainty. Climate scientists use obscure methods to collect climate data and seemingly unwieldy models to make predictions about the future. We hear about the potentially apocalyptic outcomes of climate change, and yet, ahhh, I walk around outside, and it’s sunny and calm, and the world remains lovely here in Boston for yet another day. It is pressing that people care about this practically invisible abstraction, but why?
These complex elements alone lend themselves to misconception, but add to the mix a few opposing political campaigns that touch deeply personal values, and your jittery, ominous concerns may be met with a plenitude of responses ranging from the mild, maternal, and marginally comforting, “Oh, honey. It’s not that bad,” to something much more enraged and defensive. Hopefully, “How to Explain Climate Change to Your Own Mother: A Guide in Multiple Installments” will help increase your understanding of the (possibly literally) hottest problem of our times, as well as build up your arsenal of scientific evidence and climate discussion fodder. This guide will examine what a climate scientist actually does, untangle the range of outcomes climate change may bring, deconstruct a couple of my personal favorite misconceptions, and discuss some of the other societal and political barriers preventing public understanding of and action around climate change.
To kick off this guide, however, I’d like to start with exploring some of the basic science behind climate change. Greenhouse gases and that nebulous beast also known as carbon are particularly logical threads to begin pulling on when fiddling with that giant, scratchy climate change sweater. Earth’s atmosphere is made up of a number of gases. Oxygen and nitrogen together make up 99% of gases in the atmosphere, but traces of other gases such as argon, water vapor, and nitrous oxide are also present in the mix. While oxygen and nitrogen let heat from the sun permeate down to Earth and then back out into space, a few trace gases—remember, gases that make up less than 1% of our atmosphere—absorb and trap the sun’s incoming heat without letting it reradiate out into space. The key players here are carbon dioxide, methane, water vapor, and nitrous oxide. They have the same physical properties as the glass in a greenhouse, and lo, they are deemed greenhouse gases. Good thing, too—these gases are the reason Earth’s average temperature is above the freezing point of water, even though they compose a relatively teensy amount of our planet’s atmosphere. Small, but potent, these greenhouse gases are essential for life. Without them, Earth would look a lot more like its runty pipsqueak little brother, Mars.
Greenhouse gases enter the atmosphere in a variety of ways. Burning trash can release nitrous oxide into the atmosphere, while methane can come from cow burps. Each gas has its own unique source, cycle, and potential for absorbing heat, but this installment will focus specifically on the dynamics of that infamous, gaseous behemoth, carbon dioxide. Carbon itself takes on many forms. Carbon dioxide gas can become carbonic acid, as it is absorbed by ocean water. Plants take in carbon dioxide and water to make sugars and give off oxygen in a photosynthetic symphony. When animals eat plants, they rearrange these sugars into other sugars, as well as fats; subsequently, when animals breathe, they breathe out gaseous carbon dioxide. Organisms then die and decay, further giving off carbon into the atmosphere or remaining sequestered as carbon in the soil. Carbon can also be a part of the compounds that make up rocks and fossils. Again, some natural processes give off carbon dioxide, like when animals breathe. Other natural processes take in carbon dioxide and rearrange it to make all the aforementioned compounds, like when plants photosynthesize. A handy, semi-interactive guide on the carbon cycle can be found here, perfect for ages 7-150.
Now, it’s no secret that human activities contribute massive amounts of greenhouse gases to the Earth’s atmosphere. While the organized burning of trash and breeding of flatulent cattle are not exactly “natural” earthly processes, the release of carbon dioxide through the burning of fossil fuels is one of the biggest man-made perpetrators in changing the chemistry of our atmosphere. A fossil fuel is the generic name for a fuel made out of dead organisms that have been compressed underground for hundreds of millions of years. The compression of these ancient creatures results in carbon-rich fuels such as coal, natural gas, and petroleum, all of which human beings dig up and use to drive cars, light up light bulbs, operate factories, grill kebobs, and generally live comfortable, modern lives. These are great feats of human engineering, really, but their effect on the atmosphere is gigantic, even though the atmosphere is gigantic itself. There are a number of figures, graphs, and empirical, measured data that could tell you just how large this influence is—in metric tons, in rising parts per million—but I find that the slightly more qualitative truths in this situation make for a more visceral explanation: when we combust fossil fuels, we release, in mere seconds, gases that have been sequestered underground for hundreds of millions of years. This is significant. Significantly more carbon dioxide in the air means significantly more heat-trapping gas in the air means a significantly changing climate.
Again, the amount of carbon dioxide we release is a physical, demonstrable reality. These gases’ absorption of relatively large amounts of heat from the sun is a physical, demonstrable reality. Scientists in the 19th century understood these physical realities; they were demonstrated as early as 1859 by John Tyndall and have been repeatedly demonstrated since. Around this time, humans had already entered the industrial era, signifying the start of an anthropogenic journey fueled by ancient, compressed organisms. Based on Tyndall’s experimental evidence (as well as evidence from many other scientists at the time), early climatologist Svante Arrhenius was essentially able to make the first rudimentary, but plausible predictions about our changing climate all the way back in 1895. The 19th century! Before 20th century subcultures and politics, before 21st century internet message boards!
Of course, there are many more lines of physical evidence we could trace to the root of what’s driving climate change, but my mother would have likely left the kitchen table at this point to go do anything else. So stay tuned for next time, where we will investigate how scientists measure climate change, how they make predictions and projections, and the various possible outcomes that climate change may bring. (Hint: more than just a sad polar bear on a melting arctic ice floe.)
- EPA, April. Inventory of US greenhouse gas emissions and sinks: 1990-2009. EPA 430-R-11-005, 2011.
Fleming, James Rodger. Historical perspectives on climate change. Oxford University Press, 2005.
- IPCC Fourth Assessment Report, 2007
- Kahan, Dan M., et al. “The polarizing impact of science literacy and numeracy on perceived climate change risks.” Nature Climate Change 2.10 (2012): 732-735.
Maibach, Edward, Connie Roser-Renouf, and Anthony Leiserowitz. “Global warming’s six Americas 2009: an audience segmentation analysis.” (2009).