I recently read of efforts by a young Swiss duo, both engineers, whose company, Climeworks, sucks CO2 out of the air and carbonates water, injecting the water underground into basaltic rock. To its own surprise, Climeworks finds that the gas converts to solid carbonate forms underground in a couple of years. So is this a stable way to remove greenhouse gases from the air? There are other uses for captured CO2 of course but the quantities are minuscule compared to global emissions. So the pundits talk of capturing the carbon dioxide and storing it in underground caverns or pumping it under pressure into the depths of the ocean. Why isn’t there more talk among technologists of reducing emissions, instead of accepting emissions as a given and figuring out ways of converting them at great cost to benign forms?

A friend recently commented on efforts to remove atmospheric CO2 and store it underground. It’s like swallowing gas, he says. You know what happens when you have too much gas. You either fart or burp, or both. Accumulated internal gas is painful and you wouldn’t do it to yourself, so why do they want to do it to the earth? Do they know what will happen when the earth farts? So why don’t we plant trees instead?

Relative strengths of major greenhouse gases. Image courtesy IPCC

Planting trees is a solution. An average tree sucks up 25 kilos of carbon per year. Humans emit 30 to 40 gigatons of CO2 every year. Let’s say emissions are kept at 30 gigatons a year. Thirty billion tons. That’s… let’s see, forty trees take up one ton per year, so multiply 30 billion by 40… so you get 1,200 billion. That’s 1.2 trillion trees per year just to break even!

How many trees are there on earth already? I found a BBC report of a 2015 Yale University study that estimates the number of trees currently on earth at 3 trillion. That’s 3,000,000,000,000. Since atmospheric CO2 concentrations are going up steadily, the situation would be much worse without these 3 trillion trees. So we still have to suck up the additional 30 gigatons a year, or else reduce emissions. If we take 7 billion to be the global population, leaving aside the old, the infirm and the very young, that leaves around 3 billion people of tree planting age worldwide. In order for 3 billion people to plant 1.2 trillion trees per year, each one will have to plant 400 hundred trees per year.

Persistence of greenhouse gases in the atmosphere. Image courtesy IPCC

Can (and would?) 3 billion people plant 1.2 trillion trees in a year? Of course not. But if even 10% of that number were to plant 10% of the target, we would be well on our way to doing what we need to do. Is this realistic? Quick answer: No. So is there a quick fix? Yes. Eat less meat. Depending on the type of feed, a cow produces 70 to 120 kg. of methane per year. Remember, methane as a greenhouse gas is 23 times more potent than CO2, so cutting down on meat is a quick way to reduce emissions. And it has the added benefit of freeing up pastureland for tree planting. So now we’re beginning to get a handle on things.

If we pump huge quantities of CO2 underground and undersea, the earth might fart (so to speak), with unintended consequences. But cows already fart on an ongoing daily basis, emitting considerable quantities of methane, so eating less meat is a relatively painless quick fix. And then there are lots of concomitant steps that are in the process of hesitantly being implemented, like switching to public transportation and electric cars. And, oh yes, the most environmental step the world is taking is the #MeToo movement! Let’s write that on our foreheads as a reminder to the world. Education and empowerment of women is the fastest way to reduce global greenhouse gas emissions and save our planet.