By Helen Ecker··an average:
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Oddly enough, the weather could be getting (much) colder instead of warmer in the Netherlands, as a result of global warming. Climate scientists are increasingly concerned that an important ocean current that brings warm air our way could be shut down.
A shipping container full of measuring equipment will leave for Greenland on Friday, so they can take measurements in the ocean on site. The research focuses on what’s called the AMOC, a tidal current in the Atlantic Ocean that carries warm ocean water to the Arctic and also keeps us warm. The AMOC is at risk of reaching a tipping point sooner than expected.
“I hope you don't try it”
If that happens, it will likely happen at such a rapid pace that it will be very difficult for people to adapt, one expert has concluded. Stady Earlier this year, KNMI, TU Delft, Utrecht University and the NIOZ Institute for Marine Research called for broader research.
Femke de Jong is in charge of the research mission to Greenland at NIOZ. According to her, there is no longer any doubt whether the AMOC will decrease in strength. “But whether the flow is really ‘collapsing’ is still a matter of debate. That is why there is reason for further research. This is scientifically interesting, but personally I hope that I will not be exposed to the collapse of the AMOC.”
“A drop in temperature of five to ten degrees.”
Scientists believe that the consequences could be dire, especially in Western Europe. In a relatively short time, depending on the climate policy followed, a completely different climate could develop, leading to a sharp cooling in Western European countries.
Some scientists estimate that this could lead to a temperature drop of five to ten degrees in a number of places in northern Europe, while in our country it could reach three to five degrees, although research into this is still ongoing. Others believe that it will be less.
René van Westen from Utrecht University is currently completing a study into the potential impacts in the Netherlands. “The cooling effect could cancel out the warming in the Netherlands, and could be even stronger,” he says. His research will be published later this year.
Rapidly reduce carbon emissions
Although much remains unclear about the AMOC, climate scientists are in complete agreement on one thing: concerns about the Gulf Stream’s demise once again underscore the need to rapidly reduce greenhouse gas emissions. Because these emissions, especially carbon dioxide, ultimately push the AMOC to a tipping point.
What is AMOC?
AMOC is an acronym for Atlantic Meridional Overturning Circulation. This ocean current comes from the south and flows towards the North Pole. There the water cools, sinks several kilometers to the depths, and then flows back south.
Because all the water in the ocean is connected to each other, the Gulf Stream affects climate around the world. As a result, if it stops, ecosystems and rainfall patterns around the world could change, and sea levels could rise even more.
Whether and when this tipping point will occur is a complex question, says Professor Caroline Katsman from TU Delft. “We may have already achieved it, but we can’t prove it because we have so few observations in the deep sea.” She compares it to a cartoon, where a cartoon character runs up a cliff and hangs in the air for a moment before falling.
reduce emissions
Only when the cartoon character falls does it become clear that there is no solid ground under his feet anymore. “We may have already crossed that abyss. But unlike this kind of comic, we still have influence over the process.”
It is expected that if emissions decline soon, the AMOC will slow down more slowly.
To get more certainty quickly, scientists from several institutes have submitted a research proposal. One thing they want to investigate is whether climate models are right on this point. “There’s a strong suspicion that climate models underestimate the possibility of reaching the AMOC tipping point quickly,” Katzman says.
Ocean measuring stations
Concerns about the AMOC have grown dramatically in the past year, in part because the Atlantic Ocean has warmed dramatically. It’s still not clear what’s causing this. It’s becoming increasingly clear that ocean temperatures are a better indicator of climate change than the atmosphere. Seawater absorbs 90% of the extra heat generated by greenhouse gas emissions.
There have been many temperature stations on land for more than a century. There are far fewer of them in the ocean. This makes it difficult to understand the processes that play a role in its warming.
