Global Warming – Geological Perspective

Carbon-silicate cycle.

A recent study by Columbia University scientists found an interesting way to extract atmospheric carbon, which aims to reduce greenhouse gases and global warming. CO2 is converted to inert and solid minerals such as calcite when it comes in contact with peridotite, which is very common in the Earth’s mantle, but more rarely on the surface. In the Sultanate of Oman, large amounts of peridotite have been exposed on the surface, and geologist Peter Kelemen and geochemist Juerg Matter claim that the natural process can be intensified to produce underground minerals that can sustain two billion tons of CO2 released each year by human activity. Source – Reuters / IOL Timothy Gardner

Al Gore is campaigning to reduce greenhouse gas emissions, and the Kyoto Protocol expires in 2012, however, we are not close to significantly reducing greenhouse gas emissions. However, at this stage, I do not intend to deal with climate change, but rather to focus on an amazing system that will keep the Earth’s climate within certain limits for a long time, and this will keep our planet in good living conditions – carbon silicate. period.

We can have a negative impact on the climate for centuries and even decades, but if we look at the issues from a geological point of view, these man-made disturbances in the great broom of geological epochs are insignificant and will not affect them. long-term productivity of the planet. However, we can suffer a lot during these short-term earthquakes – an increase of 5 degrees will make large parts of our planet uninhabitable. A distorted sense of importance worries us about our future on Earth, but only if we accept that our superiority can be anything other than a lucky roll of the dice of evolution, and that the survival of the human species is irrelevant. As for the future of the planet, then we can to some extent stop worrying about our possible role in the grand scheme of the universe. Whether we like it or not, we will eventually perish, but life will continue in countless different forms until the last supernova of the sun.

But let’s move on from philosophy and speculation to our immediate surroundings and some harsh facts about how the Earth’s climate is maintained within these important boundaries. Most of us are aware of continental landslides and plate tectonics, where the Earth’s crust is reworked as slabs fall along the edges of the plates. Where the sinking plate melts, it descends into the flames of the Earth, and its constituent elements return to the rock age with volcanic activity.

One of the most important elements of this period is calcium, which is widely used by organisms, including humans, to form shells and bones. Add a little carbonic acid to the mixture, and calcium carbonate – CaCO3 is formed – is the most common form of limestone. Limestone is one of the most common sedimentary rocks and generally represents ancient coral reefs preserved in geological records. The development of coral reefs sequestrates large amounts of atmospheric carbon over millions, sometimes billions of years, until limestone enters a tectonic mill or is exposed to erosion and erosion agents. The more CO2 in the atmosphere, the sooner limestone will form, provided there is enough calcium.

The question is, what is the source of calcium? It is formed from igneous, sedimentary and metamorphic rocks that are formed by volcanic activity as a result of plate tectonics. The same eruptions that scatter CO2 into the air deliver the chemicals needed to remove it, thus keeping everything in balance. Surprise! Wow!

Now we need a source of carbonic acid. Erosion of silicates – feldspars and micas in common rocks such as granite and sandstone forms calcium, silicon, water and all essential carbonic acids. Now, as we have already seen, the more CO2 there is, the faster limestone is formed, and the same CO2 is removed from the system. Similarly, the higher the concentration of CO2, the warmer the planet – a sad fact that we find in our value. This leads to an increase in evaporation, which in turn leads to an increase in rainfall and, consequently, an increase in weather conditions.

The greater the amount of erosion, the greater the formation of carbonic acid, which in turn leads to faster limestone production. This, of course, accelerates the removal of CO2 from the atmosphere and, as a result, cools the planet. Then cooling reduces the effects of air, carbon levels rise, and the Earth heats up again. What a beautiful, self-regulating, fantastic system! However, it will take several decades or more to overcome the change in atmospheric carbon. Cold comfort is to know that high levels of carbon in the atmosphere will probably be eliminated due to the carbon-silicate period, but certainly not in the near future. Using peridotite technology can be a short-term but expensive solution to remove carbon from the atmosphere, but although it takes several thousand years for these tires to turn, there is a more efficient machine for this.