I am thrilled that the Climate March in New York City yesterday had such a huge turnout. It felt like the beginning of an important movement to finally take more decisive action. The organizers estimate that more than 300,000 people attended. Marching it certainly felt full of energy and representative of a broad cross section of society

On my way to the march I ran across a WSJ op-ed piece on how little we still know about how the climate works (via this tweet). That reminded me to write about three fallacies with regard to climate change that are important to dispel.

1. We don’t know enough about the climate and hence shouldn’t do anything.

This is a fallacy because we *are* doing something already. We are releasing a massive amount of CO2 and other human made greenhouse gases. The scientific fact that we understand very little about how climate works over the long run is the very reason we should be doing less. And less happens to include *not* release the emissions in the first place. If you suddenly found yourself on an advanced spaceship traveling through the far reaches of a galaxy would the right course of action be to press buttons at random before you understand how it works? Releasing the gases *is* pressing the buttons.

2. There are other factors that have a larger influence on Earth’s climate than greenhouse gases, such as the level of solar activity.

This is also a scientific fact but, so what? It is simply not a reason to continue emitting high levels  CO2, methane, etc. Here is an analogy. Being hit by a car has a larger impact on your health than smoking. There is a chance that you will get hit by a car. Does that mean you should smoke? Of course not. There are some things you control and others you don’t. The ones you don’t include ones with far bigger impact. That’s *always* true for individuals, companies and societies. We generally accept that this is not a reason to be complacent.

3. Requiring a carbon tax would slow down and potentially break an already fragile economy.

We aren’t great about predicting where the economy will go at any one moment, but we have learned one thing about it from the past: it is anti-fragile. Stress helps the economy. We have seen that through wars (unfortunately) and also through technological innovation (which acts as a stressor on incumbents). A big change, such as taxing CO2 emissions, would ultimately result in a significant increase in economic activity. This is now more true than ever as we already have significant investment activity and technological progress in non-carbon fields.

So next time you hear or see one of these three fallacies don’t let them stand! In the meantime it will be interesting to see what, if anything, comes out of the UN climate summit.