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It appears that one of the world's most important ocean currents could collapse, leading to unprecedented consequences across the planet. We learned this because despite the overall warming on Earth, there is one place that is actually getting colder. It is literally called a " cold spot". So what's going on? I'm here to explain everything as simply as possible so you can tell your friends about it. You may have heard of AMOC, or Atlantic Meridional Overturning Circulation. It is essentially a huge system of ocean currents that moves water north and south. In the tropics, water warms and also becomes saltier as the
salt concentration increases due to evaporation. The current then moves north towards Europe. There it releases some of its heat into the atmosphere, affecting the climate of Europe. This is one of the reasons why many places at the same latitude, like New York and Madrid, have such different weather conditions. While New York is blanketed in winter snow, Madrid remains warmer and milder thanks to the heat reaching Europe via the AMOC . When the water reaches the north, it cools, and this cold salt water naturally sinks to the depths of the ocean due to its density. And, as if on a conveyor belt, it returns south along the ocean floor, eventually restarting the cycle. This current also
transports nutrients around the world. However, scientists have noticed that this system of currents is slowing down. Although we only have a few decades of precise data from buoys across the ocean that truly indicate a slowdown, measurements of silt samples and satellite data confirm the trend. More importantly, if the AMOC were to slow down, models predict that this particular region would cool because less warm water would flow into it-and we are seeing this, despite warming in almost the rest of the world. In addition, as Greenland's glaciers are melting five times faster than they were 30 years ago, more cold freshwater is entering the area, mixing with the saltwater, diluting it.
This prevents her from sinking quickly, further contributing to the weakening of circulation. So what happens if the AMOC weakens significantly or stops altogether? This already happened about 13,000 years ago and was accompanied by a massive cooling with the formation of ice sheets in the Northern Hemisphere, creating near- glacial conditions for over 1,000 years. This turned vast areas of forests in the north into Arctic tundra and led to the extinction of many megafauna. The main theory is that it was caused by an excessive amount of meltwater from glaciers, which disrupted the flow. Perhaps even more frightening is that in some places these glacial conditions have occurred in just a few decades. If this happened today,
northwestern Europe would feel it first. Without the influx of warm air, the worst-case models show temperatures in places like Oslo reaching -50°C and in the UK dropping by 10°C. Of course, this would radically change the agricultural landscape of large parts of Europe, but the consequences go far beyond that. This would affect monsoons in Africa and Asia, changing rainfall levels and the ability to grow crops like rice that feed a huge portion of the planet. In North America, we would see a significant rise in sea levels from Florida to Newfoundland, and that's on top of the effects of global warming. Of course, these are worst-case scenarios for a complete collapse, but the reason many scientists are worried is the so-called
point of no return. It looks like a chair. If you lean back, you can usually get it back to its original position, but once you pass the balance point, there is no going back. The inertia is too great in one direction, and scientists worry that the AMOC may have a point of no return that we won't be able to overcome back. However, research shows that even a moderate slowdown of the AMOC, say by 25-40%, rather than a complete collapse, would still dramatically alter weather and climate systems worldwide. We will see much more unpredictable winters, as well as extremely hot summers across Europe. There is also the fact that when the AMOC current sinks to the ocean floor, it takes CO2 with it, leaving
less of it in the atmosphere, like a giant carbon sink. When the flow slows or stops, deep waters rich in carbon can release huge amounts of it back into the atmosphere. So what are the chances that this will actually happen? A 2023 study published in Nature estimated the likely point of no return at 2057, with a 95 percent confidence interval between 2037 and 2109. But this caused considerable controversy in the scientific community. While we have evidence from buoys measuring currents, silt samples showing flow speed, satellite data, and the presence of a cold spot, scientists believe we need more data until around 2035-2040 to make bold predictions. But the general consensus is that we
are seeing a slowdown in the flow. If you look at the AMOC flow graph, you can see that it is constantly fluctuating, and while there seems to be a general downward trend, it is difficult to say whether it will last forever. The honest answer is that we don't know yet. According to the IPCC's current position, collapse is unlikely to occur before 2100, but it is worth continuing to monitor and prepare for changes, even if it simply weakens. Thanks for watching, and see you again soon to discuss science. Peace be upon you.
