Understanding Global Warming: It’s Not Complicated
It seems that whenever politicians discuss Climate Change, the conversation turns into an “Are you a scientist?/ No, but I know scientists” exchange.
During the past few decades we have absorbed the idea that thinking about climate change requires us to be scientists. That’s just not true. To the contrary, all of us, from our common everyday experience, can understand what’s going on.
And here it is: We all know that, right now, we use fossil fuels for our energy source. These are essentially carbon: coal or carbon plus some hydrogen ― gasoline, propane, and so on. We all know that burning fuel requires oxygen ― think of candles or carburetors or fires. When we use fossil fuels, the oxygen combines with the carbon in the fuel, producing carbon dioxide. And energy, of course.
We in the United States (i.e. people, not nature) use a lot of fossil fuels. According to Lawrence Livermore National Labs, in 2014 we created 11,930,000,000,000 pounds of CO2 while producing energy to run our homes, factories, and transportation systems. (If you add the rest of the world, you get a total of 71,210,000,000,000 pounds.) That’s a lot of additional CO2 going into our atmosphere.
It turns out that carbon dioxide absorbs infra-red radiation. You may not already know this, but it’s easy to believe if you have ever used a microwave oven. In a microwave oven, water absorbs infra-red (i.e. “beyond red” — or, technically, anything beyond about 800 nm) radiation (oddly enough, the wavelengths in a so-called “microwave” oven for safety reasons are much longer than microwaves), gets hot, and transfers that heat to whatever else is in there. (Try heating something with no water — e.g. a dry paper towel — and see what you get.)
Carbon dioxide behaves the same way. Carbon dioxide has approximately the same geometry as water — one central element, with another element on each side. In other words, carbon dioxide is O-C-O; water is H-O-H. And they behave the same: those symmetric arms on either side of the central atom wiggle up and down when exposed to the right wavelength of energy. (Like a violin string can start vibrating when a certain frequency is played on another string.) Why this is true is a topic for scientists (and philosophers), but just think of the sky as a big microwave oven (with radiation actually in the microwave region).
Carbon dioxide is very stable so it accumulates. And every year, when we use fossil fuels for energy, we (people, not nature) are emitting more and more of this heat absorbing material into our atmosphere. And the temperature in that atmosphere increases. That’s what we should expect to happen.
And sure enough, it does. The amount of CO2 in our atmosphere has gone from about 280 ppm (parts per million) in the 1800’s (the beginning of the Industrial Revolution and the beginning of a large reliance on these fuels) to about 396 ppm in 2014. At the same time, the average temperature has gone up by 1.4 degrees Fahrenheit.
Making things warmer (i.e. “Changing the Climate”) may seem the equivalent of moving to Florida (oh boy!), but climate isn’t really the most immediate problem. Of course, there are the longer term effects of increasing the amount of water in the ocean from melting ice, and the expansion of the ocean due to its increased temperature, both of which are leading to rising sea levels, but that’s a problem for maybe island countries in Asia or somewhere else far away.
The problem already upon us, right here and right now, is what making things warmer is doing to the weather.
Most people have some sense that our weather is getting a little strange: We live with temperature swings that we don’t quite remember from our childhood — sometimes 30 degrees from one day to another. We read about a “thousand year” storm in South Carolina, with rainfall of 16 to 24 inches in just three days. California is in the fourth year of a “100 year drought”, fighting record forest fires and record mud slides. It’s actually hard to keep up with examples — a few days ago, Texas had up to 20 inches of rain in a few days.
We reassure ourselves — “the weather is always changing” . . . and we’re right. Sort of.
In fact, the nature of weather is that it is always changing; it’s the result of many different cycles imposed upon each other, the 24 hour rotation of the earth; the 365 day cycle of our elliptical path around the sun; the 7 year cycle of sun spots; plus the incredibly important circulation patterns in our atmospheric and in our ocean moving heat from the equator to the poles. All moderated by geography (think of El Nino).
The critical point is that when we heat up the atmosphere we (again, i.e. people) are changing those cycles, and that is also something that we can understand. Think of our weather system as a chimney. If you build a chimney correctly, you will get a good “draft”, and the smoke will go straight up. If you make the chimney too short, or too broad for its height, it doesn’t work so well. And then the draw is sluggish, and unpredictable.
That’s what we are changing. Once upon a time, the temperature difference between our icy poles and our warmer equator produced a relatively strong “draft”, i.e. a strong circulation pattern between the poles and the equator in both our oceans and our atmosphere, which in turn confined the jet stream, keeping its amplitude around 10 degrees latitude, more or less.
Today, because we are warming up the atmosphere and the ocean, the temperature difference is decreasing: we have less ice and snow at the poles, and for shorter periods of time. As you know, ice and snow are really good at reflecting sunlight — that’s why people get snow-blindness. With warming, we are creating more open water, which works in the opposite direction — it absorbs sunlight. As the poles warm up, the temperature gradient becomes weaker, and our planetary “chimney” doesn’t work as well.
The result is just what you would expect: an increasingly sluggish circulation — i.e. an unconfined and meandering jet stream. Swings are more pronounced, weather fronts go from Canada to Texas and create “super storms” (Sandy had a diameter of more than 1,000 miles); fronts get stuck and produce multi-year droughts; the warmer air carries a lot more water so when it dumps, it really dumps, flooding where no floods have ever been before. [ Note: This was written before the rains that are being blamed on El Nino — a phenomenon that once was on about a seven year cycle. What do they think generated this extreme version on an increasingly erratic apparance?]
Of course, the details of exactly what and when and understanding all of the feedback loops are subjects for scientists (and fascinating ones too). But for most of us, what’s not to understand??
Well, there is just one little thing — it’s the way our elected leaders, responsible for protecting our country and the people who live in it, have spent literally decades coming up with reasons for denying that we have a problem. (e.g.”It’s cold outside — how can you say there is warming?”)
The U.N. formed its first panel on climate change in 1988; while campaigning in 1990, George Bush Sr. said “those who think we are powerless to do anything about the greenhouse effect are forgetting about the White House effect”. Since then our leaders have gone to great extremes to keep their heads in the sand, and ours along with them. In the 2008 and 2012 elections, talking about climate change was political suicide.
What we are doing to our weather systems is already scary, and even scarier is the fact that we are continuing to add to, rather than address, the problem. We are already seeing tragic storms and destabilizing weather patterns, but we’re barely slowing down. You think refugees from Syria are a problem? Wait till we have refugees from Bangladesh, or even from California.
It’s high time we insisted that our representatives in the House and in the Senate stop pretending that this is a “debate”, and instead do something about this MOST serious threat to our country. And high time that we refuse to elect or re-elect anyone who doesn’t see the United States addressing climate change as our number one priority, with a track record to help us believe them.
One other thing I should mention –back at the beginning, when I cited the amount of carbon dioxide that we emitted in 2014, you may have noticed that we were a little above 10% of the total for the world. That’s right — the United States, with about 4% of the world’s population, is responsible for about 17% of the CO2 currently going into our atmosphere. When politicians point fingers at China and India, that is only another distraction. In fact, it is really the other way around: if we show no leadership or sense of responsibility, why should emerging economies even try?
In the ’30s we electrified American; in the ’50s we built an interstate highway system; in the ’60s we put a man on the moon. We can switch to clean energy; we can even create programs to reduce carbon dioxide in the atmosphere (hint: think plants). We can do this — if we want to have a future, we have no choice.
Mary Essary Hoyer
BS, Chemistry, Loyola University
Founder and Former Director, The Foresight Project, www.theforesightproject.org