CONTEXT
Recent studies show that the AMOC could collapse between 2025 and 2095 due to the impact of anthropogenic emissions.
About the Atlantic Meridional Overturning Circulation (AMOC)
∙ It is a system of ocean currents that circulates water within the Atlantic Ocean, bringing warm water north and cold water south and is part of a complex system of global ocean currents.
∙ The global conveyor belt circulates cool subsurface water and warm surface water throughout the world. It plays a crucial role in moderating the climate of Europe and North America and influences temperatures near the Equator.
∙ The entire circulation cycle of the AMOC, and the global conveyor belt, is quite slow.
∙ It takes an estimated 1,000 years for a parcel of water to complete its journey along the belt.
∙ Even though the whole process is slow on its own, there is some evidence that the AMOC is slowing down further.
What if AMOC would collapse?
∙ AMOC is a kind of ‘switch’ for climate in the northern hemisphere, especially Europe.
∙ It would cause widespread cooling across the northern hemisphere and less precipitation in places such as Europe, North America, China and some parts of Russia in Asia.
∙ The excess heat due to a collapsed AMOC could lead to less rainfall over the Amazon rainforest and make it drought prone and dry, and it could potentially transform it to a savannah state.
∙ A slowdown of AMOC could hinder monsoon formation and rainfall in different regions.
∙ Rainfall in the Sahel region (the West African monsoon) could reduce, the summer monsoon circulation in South Asia and India could weaken; and there might be more winter storms in Europe.
∙ Weakening of the land-sea thermal gradient weakens the sea level pressure gradient and the summer monsoon circulation over the Indian region.
| Tipping elements in the Earth’s climate system– These are the critical threshold for a system that influences the climate and ecology of the planet, indicating the point beyond which that system begins to undergo a large-scale irreversible shift.– Tipping elements include long-term loss of major ice sheets on Greenland and in Antarctica, large-scale ecosystem shifts for the Amazon rainforest and northern evergreen forests, species loss for coral reefs, shrinking Arctic sea-ice, and potential weakening of the AMOC etc.a. The collapse of AMOC could have a cascading impact on the stability of other tipping elements and climate systems of the earth. |
