Atlantic Meridional Overturning Circulation
Source: Down to Earth
GS I: Geography
Overview
- News in Brief
- Atlantic Meridional Overturning Circulation (AMOC)
Why in the News?
A major ocean current system that helps regulate climate and weather patterns worldwide may come to a halt this century, much sooner than earlier believed.
News in Brief
- Atlantic Meridional Overturning Circulation (AMOC), which moves warm ocean water from the tropics to the northern Atlantic Ocean basin, could collapse between 2025 and 2095 due to the impact of anthropogenic emissions, says a July 25, 2023 paper by scientists from the University of Copenhagen, Denmark.
- Based on the current emissions rate, the collapse is likely to occur in the 2050s, the scientists say with 95 per cent confidence in the study published in Nature Communications.
Atlantic Meridional Overturning Circulation (AMOC)
- The Atlantic Meridional Overturning Circulation (AMOC) is a crucial component of the Earth’s climate system, responsible for redistributing heat around the globe.
- It is a large-scale ocean circulation pattern that transports warm, salty water from the tropics northward in the upper layers of the Atlantic Ocean and colder water southward at deeper levels.
- This circulation is vital in regulating climate and affecting weather patterns, sea levels, and ecosystems.
Key Facts on AMOC
- Mechanism: The AMOC operates like a conveyor belt, driven by differences in temperature and salinity. Warm, salty water from the Gulf Stream moves northward along the surface, releasing heat and moisture into the atmosphere, which moderates the climate of Western Europe.
- Strength: The strength of the AMOC can vary due to natural climate variability and human-induced factors. It is typically measured in terms of the volume of water transported per unit of time, with estimates suggesting a range of 15 to 20 million cubic meters per second.
- Impacts: Changes in the AMOC can have far-reaching consequences. A weaker AMOC could lead to cooler temperatures in Europe, altered precipitation patterns, and disruptions to marine ecosystems, including shifts in fish populations and coral bleaching events.
- Potential Feedback: There are concerns that ongoing climate change could weaken the AMOC by melting ice caps, increasing freshwater input from melting glaciers and ice sheets, and altering precipitation patterns. Such changes could create feedback loops, further destabilizing the climate system.
Noted Observation
- Historical Changes: Paleo-climatological evidence suggests that the AMOC has undergone significant fluctuations in the past, including abrupt slowdowns during periods of rapid climate change, such as the Younger Dryas around 12,000 years ago.
- Contemporary Observations: Recent studies have documented a slowdown in the AMOC over the past century, potentially linked to global warming. For instance, data from the RAPID array of monitoring stations in the North Atlantic show a weakening of the circulation since the mid-20th century.
- Extreme Weather Events: Changes in the AMOC can influence weather patterns, contributing to events like the “Beast from the East,” where cold air from the Arctic is drawn southward, causing severe winter weather in Europe.
Conclusion and Way Forward
- Understanding and monitoring the Atlantic Meridional Overturning Circulation is essential for predicting and mitigating the impacts of climate change.
- Continued research, coupled with improved climate models and observational networks, can help refine our understanding of the AMOC’s dynamics and anticipate potential changes in the future.
- Additionally, concerted efforts to reduce greenhouse gas emissions and limit global warming are crucial for preserving the stability of this vital oceanic circulation pattern and minimizing its disruptive effects on weather, ecosystems, and society.
Daily Current Affairs: Click Here