People keep asking, why sea level rise caused by climate change is such an issue. It is slow and we can just adapt during centuries, no? I grew up between two seas ("Schleswig-Holstein meerumschlungen") so let me try to give you an impression what climate change means when you live at a coast.

It is true that the Netherlands and also in Northern Germany 50 cm of sea level rise can be dealt with by building the dams just higher. However, sea level rise is going to exceed this level already this century.

Furthermore, big parts of these areas are below sea level already and active (pumps, Netherlands) and passive (Siele, Germany) drainage has been important for centuries. This is what all the windmills in the Netherlands were used for.

The passive drainage will stop working at a sea level rise of 60 cm because the water pressure will be too high. Building dams higher does not solve this.

In other regions on earth the soil is too porous and the water pressure will just push the water up from below. This is happening already today – the so-called "nuisance flooding" in Miami is an example. Dams will not stop this from happening.

That said, in our region this will start only at about 60 cm sea level rise, which we will reach during this century quite for sure. It will get wet from below, not matter how high the dams are. And remember: we are talking about salt water that will leave the ground barren.

However, flooding due to storms will cause this problem way earlier than the sea level rise.

People living at the coast of the North Sea in Germany still have the oral tradition of "de grote Mandränke" that shaped the coast line and islands as we know them today. It killed at least ten thousand people in the 17th century (there was another one in the 14th century but never mind).

A more recent memory is the big flooding in 1962 where hundreds of people died in and around Hamburg. Back then, "only" the dams of the rivers broke. The sea dams were held just so. Actively, by people carrying sand sacks for several nights. And we were lucky.

This is a threat today. Combined storm and Spring tide (at full or new moon) are always dangerous. I recall the sea level just a few centimeters below the dike crown in the late 1980's, when I was still a child. I went to check every hour whether the water was still rising. This happened right after the dams were built higher. After two days the high water level dropped. The dikes did not soke through and held. "The sea giveth and the sea taketh away" is a common saying around here.

When the sea dikes should break, salt water will flood most of the Netherlands and big parts of northern Germany. Have a look at 0 m sea level rise on these maps to get an impression of the endangered areas:
coastal.climatecentral.org/map…

And storms are getting stronger and more frequent. The business as usual IPCC scenario predicts devastating storms will happen every year instead of once in a century around 2050. This means storms like "Xaver" in 2013. It caused the dike crown at Artlenburg (again: "only" a river dam) to break along 4 km. It took 2 years until repairs allowed to fight a next highwater event. It cost ~4 million Euro. Even heavier storms every year? It is nothing I am looking forward to. Actually, it scares me. A lot.

I hope, these examples show that sea level rise will not cause a slow, gradual change that we can easily adapt to. Besides losing a lot of land where we now grow food. Adding the storms makes the change way more disruptive and this is going to happen within decades, not centuries. In the Pacific Ocean it is happening now – the first village on the Fijis was relocated in 2014. But I had to learn that this is too far away and affects too few people for most of the people living here to care.

A last remark: A fast rise of the water level will destroy the wadden sea. This unique place with a huge biodiversity will be just gone. Visit this UNESCO World Natural Heritage while it still exists – it is really beautiful and comparable to the Great Barrier Reef and the Grand Canyon! waddensea-worldheritage.org/

We can still prevent all this from happening on large scale but time is running out fast. Stop burning fossil fuels now!