The Goldilocks Principle

You know the story of the Three Bears right? You will recall that Goldilocks tried three bowls of porridge and the middle one was just right for her.

The Goldilocks Principle has, in the past, been applied to the Earth, and its precise place in the solar system. It’s not too close to the Sun that the Earth becomes uninhabitable due to heat, and it’s not too far from the Sun that it becomes uninhabitable due to cold. It’s in the Goldilocks Zone…it’s in just the right place for diverse life to form, evolve and live.

Scientists have now asserted that the Goldilocks Principle also applies to the carbon cycle, as it is this, in combination with our planet lying in the Goldilocks Zone, that enables life to continue flourishing on the Earth.

They have proved that the earth has a built in carbon regulator that prevents the planet as a whole straying into a temperature band that is either too hot, or too cold to sustain life.

They have proved that the geological cycle, the overturning of the rocks that form the crust of the planet, act as an atmospheric carbon dioxide regulator.

It has been known for some time that rock that’s pushed to the surface when mountains are formed acts as a carbon dioxide sponge, it literally soaks up atmospheric CO2. Obviously if this went on without any form of counter measure the Earth would have turned into a giant snowball a long time ago as the warming effects of CO2 were removed from the atmosphere.

It has also been known for some time that volcanoes are a source of carbon dioxide, but they also put out other aerosols which, at best, would balance the carbon dioxide they release. But more often than not the aerosols outweigh the CO2 and have a cooling, not a warming, effect overall.

Scientists at the USC Dornsife College of Letters, Arts and Sciences, in collaboration with Nanjing University have found that the same rocks that soak up carbon dioxide when they are newly formed give out carbon dioxide when they are exposed to weathering which alters the chemistry of the rocks and releases the gas.

They have correlated periods of mountain building and atmospheric CO2 levels at the time the processes were occurring and have proven that there is a major effect on atmospheric CO2 during those periods. Levels are lower when mountain building is active as more “fresh” rock is exposed on the surface of the planet.

It should be remembered that the timescales here are geological, tens of thousands to millions of years, not something that could be noticed in our lifetimes. Having said that, we know that the mountain ranges we are familiar with, the Himalayas, the Andes and the Rockies to name a few, are all getting worn down, and are a good deal lower than when they first formed.

It’s that erosion that leads to chemical weathering of the rock, which in turn leads to higher CO2 levels…something we are currently experiencing. This could also explain why there have been much higher concentrations of CO2 in the atmosphere in the distant past, before humans and their cars and factories were even on the horizon, and also why there have been periods of intense cold like the ice ages that last for thousands of years.

You can read the report in Nature.com.