Tuesday, November 12. A normal Tuesday, right? Well, almost. That was the day it snowed―snowed―in Chattanooga and on the mountain. Usually, for this part of the south, the brunt of winter is after the New Year, and certainly any chance of snow fall is during that time as well. So what in the world? Does this early snow indicate that global warming is reversing, or maybe is just a myth all together?
Sorry to break it to you, but no, of course it doesn’t mean that. In fact, there’s a chance that this early snow could even be a side-effect of global warming. How does that make sense, you might ask? Doesn’t global warming mean that things will be, you know, warmer?
To answer these questions, and many more, our very own Dr. Phill Broussard has graciously offered his insight and wisdom into the issue as a whole. As a professor of physics and a lover of all things science and stewardship, Broussard has done a hefty amount of study on the concept of global warming and is here to enlighten us all. So with his help, let’s see if we can understand a little bit better what’s going on in our world, and what it means for our future.
So yes, global warming does mean that overall, the Earth is getting warmer. What’s alarming about this most of all is the rate that the Earth is warming. Broussard mentioned that the tendency of the average temperature of the Earth is to change very slowly. He said that, “[The Earth’s temperature] has usually varied about 1°C over a timescale of tens of thousands of years. The current rise of 1°C is over 60 years.”
This is a large increase, as not only is the Earth heating up, but it’s also heating up more quickly than in the past. In fact, according to the Natural Resources Defense Council (NRDC), “All but one of the 16 hottest years in NASA’s 134-year record have occurred since 2000.” This is cause for at least some attention and investigation.
This warming has a lot to do with Earth’s atmosphere and (yep, you guessed it) greenhouse gases. Greenhouse gases get a bad rep, and the term is thrown around a lot in climate change discussions, but they’re not all evil. Greenhouse gases are a part of Earth’s atmosphere contributing to the greenhouse effect.
Broussard said, “If the Earth had no atmosphere, the average temperature of the Earth would be about -22°C. The reason the Earth’s average temperature is NOT that cold is due to the greenhouse effect of the atmosphere.” Greenhouse gases are not inherently a bad thing, in fact they make the Earth pleasant and liveable. When the greenhouse gases start to pile up, that’s when it becomes an issue. Enter, carbon dioxide.
Carbon dioxide (CO2) is one of those terms you hear all the time when talking about global warming, and how big, scary carbon dioxide is heating up the planet. Exaggerated or not, there’s definitely some truth to that. The warming effect that climate change is having on the Earth is mostly due to water vapor and carbon dioxide in the atmosphere. “The water vapor produces about ⅔ of the warming,” said Broussard, “and carbon dioxide gives the remaining ⅓.”
These gases are part of the greenhouse effect, which is when the greenhouse gases in the atmosphere trap in heat from the sun that has bounced off the Earth’s surface. This is a natural and necessary process. What’s not natural and necessary is too much of those greenhouse gases. The reason carbon dioxide is promoted as so big and scary is because the increase of this gas is causing some big and scary issues.
“Carbon dioxide levels have now increased from 320 ppm [parts per million] in 1960 to over 400 ppm in 2016,” said Broussard. There are studies that have shown that as this rise in carbon dioxide occurs, the average temperature of the Earth has risen with it, about 1°C since 1960. And what’s causing that CO2 to rise? Yes, that would be us humans.
According the Broussard, “The increase in carbon dioxide can be directly tied to our use of fossil fuels, mainly coal, oil, and natural gas, to produce the energy we use for heating, transportation, and electricity.”
The NRDC agrees, stating that in the United States every year, the burning of fossil fuels to make electricity produces about 2 billion tons of CO2, with coal-burning power plants being the number one polluters. “The country’s second-largest source of carbon pollution,” the NRDC says, “is the transportation sector, which generates about 1.7 billion tons of CO2 emissions a year.”
Emissions! Another buzzword. There is lots of talk in climate change circles about humans emitting carbon dioxide and trying to become a zero emissions country. But what’s really the big deal? What’s so terrible about emissions and the Earth heating up a couple of degrees?
Christian scientist Katharine Hayhoe explains this by discussing the human body and the Earth. Over time, the Earth’s temperature has been about as stable as your body’s temperature. However, if your body heats up by one degree Celsius, nearly two degrees Fahrenheit, your body temperature jumps from 98°F to almost 100°F. Now imagine it going up another degree Celsius. It’s cause for some alarm.
On her YouTube channel called “Global Weirding,” Hayhoe explains some of the effects of this increase in temperature. She explains that the world would be affected economically, and that if the world warms by 2°C, the average GDP of many poor countries would drop by 5-10%, as climate change is likely to most negatively impact the impoverished. It would also affect population, as warmer temperatures would increase air pollution. An increase in Earth’s temperature by 2°C would mean an additional 150 million deaths (on top of the 4 million deaths already occurring) from air pollution alone.
In a report by the National Academy of Sciences that she coauthored, Hayhoe also says that per degree of warming, “we expect a 3-10% increase in the amount of rain falling in the heaviest events, a 5-15% reduction in the yield of major crops, and a 200-400% increase in the area burned by wildfire across the Western U.S.”
So, is everything gloom and doom? What can we do as humans, as Christians, in the face of our changing climate? Reducing emissions and/or cutting them out all together is a large part of curbing the rising temperatures. “In order that we prevent totally irreversible changes in our climate,” Broussard says, “we must zero out carbon emissions in about 8 years.”
This is tricky, and would take large-scale reconstruction and industrial change. In addition to backing this change, Broussard urges us to think of those who will be the most affected by climate change, the poor. “The poor are the ones who suffer from the pollution due to fossil fuel usage, and are the ones who suffer most from the extremes of weather,” he says. The common response among Christians is to “deny the reality of climate change,” and often be last in the fight to limit the damage of a heating-up planet.
As Covenant students, Broussard also encourages us to vote, and be mindful of those whom we vote for. Understand what candidates believe in terms of climate change and how it affects us, and see what industries candidates might be funded by (via opensecrets.org). In 2017, Broussard mentioned in his Chapel talk that “God views no faithful effort as too small, but we do need to respond,” which is an excellent reminder for us lowly Covenant students. Change can occur, but not without an attempt towards such goals.