This Cold Spot is a BIG Problem... And it's Getting Bigger

Summary

The video examines the North Atlantic “cold blob,” a patch south of Greenland that has cooled while most of the planet has warmed. It may be a sign that the Atlantic Meridional Overturning Circulation (AMOC)—a major system of Atlantic currents that moves heat around the globe—is weakening.

How the AMOC works

Warm, salty surface water flows north from the Southern Hemisphere. As it releases heat and some water evaporates, it becomes cooler, saltier, and denser. In the North Atlantic, it sinks and flows south at depth. This sinking helps drive the circulation.

Why the cold blob matters

A weaker AMOC transports less heat north, which could contribute to cooling in the North Atlantic. The cold patch is therefore a possible “fingerprint” of a weaker circulation, though it is not proof of an impending collapse.

Potential consequences of collapse

A collapse could have several effects:

• Europe could become substantially colder, especially in winter.
• Sea levels could rise faster near European and North American coasts.
• Tropical rain belts could shift south, disrupting monsoons that many people rely on for food and water.

The AMOC is also connected to other major Earth systems, including the Greenland and West Antarctic ice sheets, the Subpolar Gyre, and the Amazon rainforest.

Broader climate effects

Research discussed in the video suggests that the AMOC may help Earth release heat into space. If it weakens, less heat may escape overall, potentially increasing global warming even as some regions cool.

Evidence and uncertainty

The AMOC has changed abruptly in the past, including during the last ice age. Direct measurements from the RAPID array began in 2004 and suggest some weakening, but the record is too short to establish a long-term trend with confidence. Indirect evidence and climate models also raise concerns, while the likelihood and timing of a collapse remain debated.

The rate of warming and AMOC stability

Earlier assessments discussed collapse at particular levels of global warming. Research by ocean scientist Rene Van Westen instead argues that the rate of warming may be crucial.

In his model experiments, rapid warming can heat the ocean’s surface faster than the deep ocean can adjust. This can disrupt the density differences needed for sinking and overturning. Slower warming gives the ocean more time to adjust and can keep the circulation stable under much greater warming.

The model identifies about 0.3°C of warming per decade as a rate at which the AMOC becomes critically unstable. The video says current warming is around or above that level. This is a model-based finding, not a settled prediction of when a collapse will occur.

The research suggests that slowing the rate of warming could help protect the AMOC, even if warming is not immediately stopped or reversed. The presenter emphasizes that action now matters, while noting that the system has not necessarily reached its tipping point.

Researchers and sources featured

• Rene Van Westen — Researcher studying the AMOC; interviewed about his modeling and rate-induced tipping research.
• RAPID array — Buoy-based network measuring Atlantic circulation since 2004.
• The “big global tipping report” — Cited for an assessment that AMOC collapse is very likely around 4°C of warming.
• An August 2025 study — Cited as estimating a lower critical warming level of about 2.5°C.