A tipping point in the climate system is a limit which when passed can lead to massive changes in the state of the system. Tipping points are more closer due to global warming which is occurring in the modern era and will come as the earth’s temperature rises to 2 degrees Celsius as in the pre-industrial period. Potential tipping points have been identified in the physical climate system, in impacted ecosystems, and both. For example, ice cover in the northern hemisphere has increased and melted many times over a million years. Humans are ignoring the growing risk of tipping points that if passed could hamper the climate system into a less habitable climate state scientists have warned.
Research has shown that there is a higher risk of unchangeable changes to the climate system at smaller global temperature increases. There is also proof that exceeding tipping points in one system like loss of arctic sea ice can increase the risk of crossing tipping points in others. There are chances that we will lose control of this system and there is a significant risk that it will happen. It is very difficult for the climatic conditions to improve to the previous state. It is a process that is getting out of control.
Scientists have identified nine parts of the climate system which are near tipping points, some of them are interconnected:
- Arctic sea ice is very important for reflecting the sun’s energy into space but is vanishing as the planet is warming.
- The Greenland ice sheet will make the sea level rise to 20 feet if it melts.
- Boreal forests will emit more carbon dioxide (CO2) than they absorb if they get decayed.
- Permafrost,whichemitsmethane and other greenhouse gases as it melts.
- The Atlantic meridional reversible circulation, a key ocean current that would transfer global weather patterns if it stopped.
- The Amazon rainforest, which will roll over from the major absorber of greenhouse gases to a major releaser.
- Warm water corals, will dieon a large scale as the ocean warms which will hamper fisheries.
- The West Antarctic ice sheet will raise sea level by at least10 feet if it melted completely and is already in danger of melting by warming.
- Parts of the East Antarctic ice sheet will make the sea level rise tremendously if it melts.
By looking at arctic changes one can know about the links between parts of the climate system which is at tipping point and its impact on increasing effects of global warming. Diminishing sea ice increases ocean heat because it reflects less sun energy into space and makes dark water suck up more warmth. The ocean heat transfers to land and along with other heating elements melt the permafrost.
The melting of the Greenland ice sheet is also slowing down the Atlantic meridional reversible circulation, a primary Atlantic ocean current that carries heat between the northern and southern hemispheres and leads to rainfall around the planet. It will hamper monsoon rains important for agriculture in developing countries.
There are three types of tipping points in the climatic system which are:
Tipping caused by division
This happens when a particular parameter in the climate which is moving in a direction for a longer period ultimately passes through a point at which a dangerous division takes place and climate loses its stability.
Tipping caused by noise
It refers to tipping caused by changes from one state to another due to the vulnerability of the climatic system. Tipping caused by noise shows no early signs as in tipping caused by division. It is unpredictable.
Tipping caused by rate
It is tipping which is based on assumption that there is a permanent state for the particular element of the climate and if it is not disturbed then there will be only small reactions for a small stimulant. But when these changes occur more rapidly then a larger reaction may appear.
Some tipping points are closer now only
Some tipping points like the meltdown of alpine glaciers and almost total loss of coral reefs are very closer even if we meet the climate goals of the Paris agreement. There is a worry that if multiple tipping points are reached then measures taken would be enough or not in stabilizing the climate system.
A report published by the united nations has shown that despite urgent warnings about the effects of rising greenhouse gas emissions the global efforts to slow down global warming are much short of what scientists have fixed. So if we want to delay in reaching tipping points in the climate system then we have to enforce all policies related to global warming seriously.