Myth #1 The Earth is Naturally Getting Warmer – Mallory Culbertson

In the realm of climate change denial, there is a pervasive myth of “natural warming”, the idea that the Earth’s climate just naturally fluctuates between the extremes of very cold and very warm, so the warming we’re seeing is just part of that natural change. This myth takes many forms with various scientific concepts serving as the logic behind them, but the one of the most common reasons cited for “natural warming” is the Milankovitch cycles, a group of 3 planetary cycles that have to do with the way the Earth moves through our solar system. The myth is roughly as follows: there are small changes in the way the Earth orbits our sun, and that causes the Earth to receive more or less solar energy, and it happens in very regular cycles. These cycles cause seasonality and temperature variations in the Earth’s climate on a scale not unlike the change predicted to see in many climate models, so they’re clearly the culprit behind climate change, right?

If only it were that simple. The Milankovitch cycles describe the cycle of earth’s elliptical orbit (the shape of the route is circles around the sun), the cycle of Earth’s procession (where the Earth’s North pole points in space), and the cycle of the Earth’s tilt (the angle at which the Earth is tilted on its axis). The first cycle, the cycle concerning Earth’s orbit, is the cycle folks tend to blame for climate change, since it determines how close our Earth gets to the sun. The logic here is that if the Earth gets closer to the sun it gets warmer, and cooler as it gets farther away, which isn’t inaccurate. Historically, the changes in our orbit have been enough to encourage the Earth in and out of Ice Ages. However, the easiest way to debunk this myth is with the timescale on which it operates. The Milankovitch cycle in question is a slow process, as in, on the order of 100,000 years slow. The rate at which we’re seeing the climate change currently and the rate of the change we’re predicting to see if we don’t drastically scale back our carbon pollution, is more in the range of multiple degrees in the next 100 – 10,000 years, about 90,000 short of a Milankovitch cycle. So while there are in fact natural cycles that impact the Earth’s climate in a big way, they aren’t to blame for current warming trends, we are.

Let’s contemplate on this fact for a moment though. Take a second, and really consider how much of an impact our species has had on our planet. In a relatively short amount of time, certain members of our species have been able to make the same, if not greater, impacts on the Earth than the mechanics of space can in 100,000 years. How wild is that? It’s certainly not the most positive impact, but a massive impact all the same. But what could that mean if our collective species decided to make a positive impact? What sort of change could we make if we were all making it together, for the common good, for the betterment of our entire world?