The MAGA Republicans contend that climate change is a hoax. And most Democrats put climate well down their list of priorities. We think this state of affairs exists because most Americans are still in the dark on the basics of climate change. And it isn’t that complicated.
Scientists were expecting (hoping) that we’d have until the mid-2030s before the earth’s ambient air temperature would increase by 1.5 degrees Celsius (equivalent to 2.7 degrees Fahrenheit). They then hoped, assuming big cuts to fossil fuel consumption, that we’d keep the global temperature rise to no more than 2 degrees C. Sadly, we’ve ALREADY exceeded a 1.5 C increase for most of the last 18 months. America’s most famous climate scientist James Hansen says we’ve already blown past 1.5 C and most scientists now believe we’ll blow by 2 C in the 2030s. Furthermore, half of all scientists surveyed believe we’ll blow past 3 C by 2100 (5.4 F). Looks like the scientists were too conservative.
The slice of the atmosphere that really matters is only 7 miles thick. That’s it. The volume of the atmosphere is 7 times the 197 million square mile surface area of earth: 1.4 billion cubic miles of atmosphere. That’s the volume of air that we’re pumping the CO2 and other greenhouse gases into, where they will reside indefinitely into the future.
100 years ago, the CO2 concentration in the atmosphere was around 300 ppm. It’s now 427 ppm, a 40% increase. Sunlight passes unobstructed through the atmosphere and produces radiant, infrared heat. That heat reflects back up into the atmosphere. However, CO2 and other greenhouse gases like methane block the radiation from escaping the atmosphere. Turning up the density of greenhouse gases around the planet is like turning up the knob on an electric blanket. And there’s a delay from when you add the CO2 and when you start to feel warmer, just like an electric blanket. As a result, we’ve already got much warmer temperatures baked in for the next few decades even if emissions went to zero tomorrow.
We know how much crude oil, natural gas and coal is produced and burned on the planet every year and therefore the amount of CO2 and other emissions pumped into the 7 mile thick atmosphere. In 1966, we were pumping 11 billion tons per year, in 1990 about 21 billion tons and in 2024 about 40 billion tons. With emissions of this magnitude, we’re going up by 2.84 ppm per year of CO2. At this rate, by 2050 we’ll be close to 500 ppm, a 66% increase from the 300 ppm just 70 years ago.
In 1896 the Swedish scientist Svante Arrhenius predicted that a doubling of atmospheric CO2 would produce global warming of 5-6 degrees Celsius or 9-11 degrees Fahrenheit. Exxon scientists predicted in the 1980s that doubling CO2 in the atmosphere would increase global temperatures by 2 to 3 degrees C. That number now seems low as we’re already up 1.5 C with only a 40% increase in CO2 levels. Other reputable scientists have predicted warming of as much as 7 to 14 degrees C from a doubling of CO2 in the atmosphere. So, the truth probably lies somewhere in the middle.
You can’t blame folks for being in the dark, or worse, believing it’s a hoax. It wasn’t taught in school, and you won’t get it from your favorite newsfeed. It took me (Doug) some months of studying in 2019 to boil it down to this understanding. Once so informed, we at TCC started studying and writing about solutions. It’s not a good story and we’re past the time when it would have merely been “hard" to solve. We’re hoping with a Harris/Walz administration and a sensible Republican party that great things can be achieved!
