Why is News :
- A recent climate study warns of a potential collapse of AMOC, which could lead to a prolonged winter freeze in Europe, even amid global warming.
- AMOC’s decline is now viewed as a possible tipping point in Earth’s climate system.
What is AMOC?
- A major component of global thermohaline circulation, often described as a climate conveyor belt.
- Transports warm water from the tropics northward (e.g., via the Gulf Stream) and returns cold, dense water southward at depth.
- Regulates Atlantic temperatures, stabilizes climate, and supports marine ecosystems.
How AMOC Works
- Warm, salty water flows north, cools in higher latitudes (North Atlantic), and sinks due to increased density.
- This cold, deep water then flows southward, completing the circulation.
- Drives heat and nutrient distribution, impacting weather patterns from the Amazon to the Arctic.
Current Status and Risks
- AMOC has weakened significantly since mid-20th century.
- Projected to slow by 18–43% by 2100.
- Key driver: Melting of Greenland Ice Sheet increases freshwater influx, disrupting salinity and density gradients.
- At risk of crossing two major tipping points:
- Salt-transport feedback
- Deep-ocean convection threshold
Consequences of AMOC Collapse
What Are Climate Tipping Points?
- Critical thresholds in Earth’s systems beyond which irreversible and self-reinforcing changes occur.
- Even a small temperature or pressure change can push systems into catastrophic new states.
Key Tipping Elements at Risk
- Greenland and West Antarctic Ice Sheets
- AMOC
- Amazon Rainforest Dieback
- Arctic Permafrost Thaw
- Coral Reef Collapse
| UPSC Relevance : GS1Geography, OceanographyOcean currents, climate geography GS3Environment, Disaster ManagementClimate change, extreme weather risksEssayEnvironmental Ethics and Global CommonsClimate justice, global interdependence UPSC Mains Questions Climate tipping points represent irreversible damage to Earth systems. Discuss their significance in global environmental policy. (GS3) |