Until recently, measurements off the Dutch coast showed no apparent acceleration in sea level rise. But the newer numbers push the measurements statistically over the edge. Researchers from TU Delft actually came here last year for the result Sea level in the Netherlands is rising faster today than it was thirty years ago. Deltares scientists now also see acceleration using a slightly different method. It is only possible to draw a line through the series of measurements by twisting it up around 1993.
Previously, the sea level in the Netherlands rose at a rate of 1.8 mm per year, the institute notes, to 2.9 mm at present. In fact, the pace has not increased suddenly since 1993, but it has increased gradually, as researcher Bart van den Horek confirms. ‘But you get the best.’ suitable With notes if you made a grille that year.
The United Nations Climate Panel (IPCC). already noticed That global sea levels are rising faster and faster, due to the expansion of ocean warming and melting of glaciers. However, this acceleration was not evident at the guard stations at Delfzell, Harlingen, Den Helder, Imweden, Hoek van Holland and Vlissingen. Perhaps because the sea level fluctuates wildly every year, due to gusts of wind and currents.
mirror sea
The issue came to the fore five years ago, when geologist Salomon Cronenberg referred to it in his book. mirror sea. There has certainly been an acceleration in carbon dioxide emissions2so sea level was supposed to react to that, right? De Volkskrant. Even then, critics have suggested that the increase may have been hidden in the wildly fluctuating Dutch numbers.
About the author
Martin Keulemans is science editor for De Volkskrant, specializing in microlife, climate, archeology and genetic engineering. He was named Journalist of the Year for his reporting on the Coronavirus.
Recording in a file Sea Level Monitor, official report It is the coastal policy that now settles the issue. “Especially people who focus on a local perception of the problem sometimes say: It’s clearly not that bad with us, and we don’t have to do much about it yet,” says Van den Hork. “But now we can establish: What we see around the world, we also discover here.”
This does not mean that sea level rise scenarios need to be modified upwards. KNMI assumes that the sea near the Netherlands will be somewhere between 30 and 121 cm higher than it was at the end of this century, mainly depending on how much greenhouse gases the world emits, and whether the melting of Antarctica in particular will gain momentum. . . By the way, the most likely increase is less: from 44 to 76 cm.
More acceleration
Meanwhile, observations off the Dutch coast lag distinctly behind most climate scenarios. But that doesn’t say much, van den Hork believes: Sea level scenarios are particularly good in long-term trends. From the point of view of risk management, I would find it irresponsible in any case to say: it’s not so bad. The reality could eventually turn out to be more dramatic than the scenarios, due to faster melting of glaciers and other ice masses.
The rise is likely to accelerate further, says sea level expert Riccardo Riva (TU Delft), who was not involved in the Deltares study. If you look at the global acceleration, we’re going to add about a tenth of a millimeter every year. I expect to see that here too. Riva says she is “very happy” with the new analysis: “Their method is different, and yet we agree. It really couldn’t be more beautiful.” When asked, Cronenberg said he didn’t have time to take a closer look at the results.
By the way, the mod will not change much in everyday practice. At most, the new series of gauges will help determine how much sand is being deposited in place, in order to keep the coastline safe.
