Global warming basics – Part 1: Why CO2 is not the villain

How it started – CO₂ on the rise

Since 1956, Charles David Keeling started to measure CO₂ levels. He soon noticed that CO₂ levels were at their highest in April and dropped to their lowest in October, before they started rising again.

Why does CO₂ have such seasonal variation? The northern hemisphere is comprised of most of the Earth’s land mass. On land, green plants grow and take up CO₂ from the air in spring and summer, thus drawing down large proportions of CO₂. In autumn and winter, when plants don’t grow, CO₂ levels rise again.

Overall, since that first measurement in 1956, the average level of CO₂ has been increasing every year.

And the world has related the rise in CO₂ levels to burning of fossil fuels.

Are fossil fuels to blame for rise of CO₂ levels in the air?

Walter Jehne, Australian soil microbiologist, says that Earth’s yearly CO₂ emissions are over 130 billion tones of CO₂ overall. Every year, about 120 billion tons of CO₂ are draw down. So there is extra 10 billions tons of CO₂ that is accumulating every year, leading to overall CO₂ rise in the atmosphere.

What proportion of Earth’s CO₂ emissions are actually associated with burning fossil fuels?

Fossil fuels contribute to mere 8 billion tons of CO₂, yearly.

And the planet’s atmosphere is accumulating 10 billion tons of CO₂ every year. So even if we stopped use of fossil fuels tomorrow, CO₂ levels would continue to rise.

Decreasing CO₂ levels – pointless exercise?

Plus, if we managed to remove not just 10 billion tons CO₂ that is extra every year, but even more (20 billion tons) to achieve carbon negative future – we still won’t see our results any time soon.

That’s because of the oceans. They store huge amounts of CO₂ and have been soaking up the excess from the air for the past 50 years. That has led to acidification of the oceans.

So once we start drawing down more CO₂ from the air, the oceans will respond. They will release CO₂ they have been storing in their waters and this would continue for 1000s of years.

Yes – me, you, our children and grandchildren will never see lower levels of CO₂ in the air. We may manage to stop the yearly increase, but that’s about it.

But don’t despair. CO₂ is just a symptom of a problem, not the problem itself…

The planet is heating up

There is no question about the fact that the planet is heating up. Sun’s radiation hits our atmosphere with a certain energy (at a power of 342 Watts/m²). If the climate was to remain stable, equal energy of radiation should be released back into space. But it isn’t.

In fact, less energy is leaving the planet (power of 339 Watts/m²). That means, our planet is getting hotter.

And CO₂ is responsible for only less than 4% of heat dynamics of our planet.

Water governs 95% of heat dynamics of our planet

Water vapour is responsible for how heat is handled in the atmosphere.

Why is no one talking about it? Why have we not modelled the effect of water on climate before?

That’s because it’s variable – it depends on temperature and many other factors. Just as weather cannot be predicted years ahead, water dynamics, or hydrology, cannot be either.

Scientists thought, water is Nature’s business and humankind has no control over it.

But we are responsible for far more than we realize. We manage nature – and we’ve changed it beyond recognition.

Read Part 2 to find out more.