Icon: enlarge
Permafrost soils (in Alaska)
Photo: Smith Collection / Gado / Getty Images
What are tilting elements?
Tilting elements are parts of the Earth system whose climate-related changes can themselves have a significant impact on the climate.
In this context, tipping points are often used.
This is how researchers describe critical thresholds in the climate structure which, if exceeded, can lead to climate change.
Often it is a self-reinforcing process that can hardly be reversed by countermeasures and continues to run even if the actual cause has already been eliminated.
The best way to imagine is a house of cards from which you can initially easily withdraw one card after the other without anything happening.
But then the structure suddenly collapses completely without further cards being drawn.
Why are tipping elements so important in the climate crisis?
A classic and well-known tipping element are the permafrost soils in Siberia or North America.
When these permanently thaw deeply frozen soils, they release huge amounts of the greenhouse gases CO₂ and methane, which they have stored in the form of carbon compounds for centuries to millennia.
The thawing process is also accelerated because microorganisms in the soil decompose these carbon compounds and thereby release heat into their surroundings.
It is estimated that the top three meters of the permafrost soil alone contains 1,000 billion tons of carbon.
The melting of the Arctic sea ice can also be seen as a critical tipping element.
As the white ice surfaces on the sea disappear, more and more of the darker sea surface is exposed.
Unlike ice, this hardly reflects the sunlight, but mostly absorbs it, which in turn leads to a rise in temperature and the melting of further ice surfaces (ice-albedo feedback).
Researchers have identified more than a dozen of such larger tipping elements, including the destruction of ecosystems such as the Amazon rainforest or changes to wind systems such as the jet stream over the northern hemisphere.
It is believed that the various elements influence each other.
A kind of domino effect would be the possible consequence that could possibly bring the earth a new hot season in the end.
When exactly and whether certain tipping points will be reached is often not clear.
Some researchers warn that certain tipping points have already been exceeded and other systems could pull along.
Previous climate term: Kyoto protocol.
