Narcissistic President of The USA Believed Fox News Claims

One shouldn't bring attention to the current idiocy in charge of the USA, not when my own Government is in the process of bringing the UK to the edge of a precipice. But this particular tweet from Donald Trump repeats such a common place fallacy that it it's worth going over why it's wrong.

On the 12th of March 2019 the President of the United States of America thought it worth his time to tweet:

Patrick Moore, co-founder of Greenpeace: “The whole climate crisis is not only Fake News, it’s Fake Science. There is no climate crisis, there’s weather and climate all around the world, and in fact carbon dioxide is the main building block of all life.” @foxandfriends Wow!

— Donald J. Trump (@realDonaldTrump) March 12, 2019

Ignoring the question of whether Patrick Moore was a co-founder of Greenpeace (he says he was, Greenpeace say he wasn't), or why it matters, the issue I'm focusing on is the claim that in fact carbon dioxide is the main building block of all life.

I have two main problems with this: 1) it's irrelevant and 2) it's not correct.

Irrelevant

It's irrelevant because it's implying that something either has to be good or bad and cannot be both. In fact many things are important or essential for life but can also be deadly in other contexts. Water is essential for life, but even a small amount can drown you. Iron is essential for life, but you wouldn't want to be hit on the head by an iron bar. Sunlight is the source of all life, yet that doesn't mean you can ignore the risks of sunburn. (The people who argue for more CO2 on the grounds that it's the gas of life rarely argue for more solar panels despite solar energy being the source of nearly all energy.)

Incorrect

Now it's a fact that carbon dioxide is essential for the life cycle, but it is not correct to call it the main building block of life. It's carbon that is the main building block of life, carbon dioxide is just the main delivery system for carbon.

A very simplified description of the role of carbon in the life cycle of plants and animals goes something like this:

• Plants absorb carbon dioxide from the air.
• Plants use energy from the sun to convert the carbon from CO2 into carbohydrates, releasing oxygen in the process. The carbon as a store for solar energy.
• During the night plants burn some of the carbon for energy, creating carbon dioxide which they release into the atmosphere.
• Animals do not use carbon dioxide at all. They either eat plants or other animals, stealing the carbon and energy stored by the plants.
• Animals burn carbon for energy by breathing in oxygen and combining it with the stored carbon, producing carbon dioxide as a by product
• This carbon dioxide is breathed out as a waste product.

The point of this is that whilst it's often suggested that carbon dioxide is a live giving chemical, the reality is that for humans and other animals it's at best useless and at worst harmful and even deadly. It's an irony that long before anyone coined the term gas of life, carbon dioxide was mainly know as a killer gas.

None of this, of course, has anything to do with the problem of CO2 emissions. The problem with increasing atmospheric CO2 is the danger of increasing the greenhouse effect and so warming the planet. Nothing to do with whether you view it as beneficial to your health or not.