terça-feira, 17 de dezembro de 2019

When will the Netherlands disappear?



When will the Netherlands disappear?

The low-lying country has centuries of experience managing water. Now climate change is threatening to flood it completely.

By NAOMI O'LEARY 12/16/19, 7:30 PM CET Updated 12/17/19, 4:42 AM CET

Illustration by Steven P. Hughes for POLITICO

OVERDIEPSE POLDER, Netherlands — The local phonebook in the Dutch area of Noordwaard is a record of a community that no longer exists: Lists of numbers for homes that have been demolished, leaving just square patches in the grass where their foundations stood.

Once a thriving farming area, Noordwaard is now an expanse of reedy marshlands in the southwest Netherlands, deliberately designed to flood in order to keep nearby Dutch cities dry. "Several years ago, when you came to that polder, big nice farms were there, acres with potatoes and onions," said Stan Fleerakkers, a dairy farmer who lives nearby. "Now when you drive there, there's nothing left of it."

The Noordwaard polder was one of 39 such areas selected for the Dutch government’s “Room for the River” program, in which land was given back to the water. It’s a modern reversal of the centuries-old practice of land reclamation by the famously low-lying country.

It’s also a snapshot of the future the country faces: With unprecedented sea level rise forecast as a result of climate change, the Dutch government is racing against the clock to figure out how to keep one of the world’s richest countries from disappearing into the North Sea.

Sea rise forecasts range from levels that are manageable as long as the increase is gradual, to doomsday scenarios that would outpace authorities’ ability to respond. Quietly, experts are beginning to model out potential futures on behalf of the government.

If emissions continue on current trends, the IPCC predicts 84 centimeters of sea rise by 2100, and as much as 5.4 meters by 2300

In more optimistic scenarios, the feted Dutch dikes, storm barriers, pumps, and adaptations can cope, but at a cost — and even then only up to a point.

“On the other end of the spectrum is controlled abandonment, which isn’t nice, because we somehow need to lead 10 million people somewhere,” said Maarten Kleinhans, professor of geosciences and physical geography at Utrecht University. “And as soon as this gets known, as soon as the shit hits the fan, there won’t be any investments anymore and local economies will collapse.”

 “This is really a nightmare scenario, but a serious one,” he added. “It could be less of a nightmare if we start planning now.”

Rising seas
A certain amount of sea rise is already inevitable, set in motion by global warming and ice melting caused by decades of carbon emissions. The Intergovernmental Panel on Climate Change, the United Nations body that collates and assesses scientific results, predicts 30 to 60 centimeters of sea rise by 2100, even if countries make good on their pledges to cut emissions under the Paris Climate Agreement. The quicker emissions are cut, the lesser the risk of unmanageable rise. But so far, the developed world is failing to meet its targets.

If emissions continue on current trends, the IPCC predicts 84 centimeters of sea rise by 2100, and as much as 5.4 meters by 2300. The IPCC has also warned that a rise of more than a meter by 2100 is not unlikely, and advised at-risk countries to plan accordingly. Such a rapid rise, with accelerating increases likely to follow, would leave many countries powerless to respond on time.

Rising sea levels create a snowball effect that accelerates the rate at which the phenomenon will continue. Essentially, the worse it gets, the worse it will get: Trapped bubbles of greenhouse gases break free, increasing global warming, and running meltwater helps destroy the remaining ice. The Antarctic ice sheet is also so large that it exerts a gravitational pull on the oceans: As it shrinks, sea water will redistribute away from the South Pole, causing an additional rise.

“We've lost almost half the Arctic ice now, and both the ice sheets of Greenland and Antarctica are losing mass and contributing to sea level rise significantly,” said Michiel van den Broeke, a professor of polar meteorology at Utrecht University.

“This is also at some point irreversible, and we should be very careful not to cross this tipping point, because that means we will be committed to sea level rises of many meters, and that is something that the Netherlands cannot cope with.”

Just how many meters of rise the Netherlands can deal with depends on the time it has to prepare, but it is in low to mid-single digits. According to the Dutch government, current defenses are adequate up to 2050. Improving them is slow work: The last 30 years of flood defense works in the Netherlands allowed it to deal with just 40 more centimeters of sea level rise.

The options available also come with trade-offs. Sand can be deposited on beaches — if there is enough time, and enough sand. Dikes can be raised, but this leaves those living inside them at greater risk if things go wrong. They are also porous: Water can be pumped out, but salt cannot. As a result, the salination of the land increases, with consequences for Dutch agriculture.

The ability to manage water is a point of pride in the Netherlands. Now, the Dutch government is trying to get ahead of the curve.

Storm barriers can be shut, but this blocks shipping to the port of Rotterdam, which accounts for a significant chunk of the Dutch economy. Interference with the shoreline also affects the Dutch fishing industry. And if the land is below sea level, the rivers that flow over it need to be pumped out over the barriers to the sea, which costs energy.

There is a point at which it doesn’t make financial sense to save the land.

“Technically, a lot is possible. We can raise coastal defenses or dikes. But at a certain point you must ask yourself if this a viable solution,” said van den Broeke. “Plan B is retreat. Give part of the land back to the sea.”

It doesn't help that vast swathes of the country are already sinking. It's a phenomenon common to the world's deltas: Human habitation stops the sedimentation processes that originally raised the land; extraction of ground water lowers it further; and the land compresses under its own weight. The jewel of Dutch wealth and industry, the megalopolis of the Randstad that includes Amsterdam, Rotterdam, The Hague and Utrecht, is located in the country's vulnerable, low-lying west.

“Some of the deepest areas in the Netherlands are 10 meters below sea level already,” said Kleinhans. “If you breached the coast now, the sea would roughly get to Utrecht, in the central Netherlands. It is really a scary situation, and there is really a false sense of security.”

Mapping the future
The ability to manage water is a point of pride in the Netherlands. Its wealth, institutional preparedness and technical know-how have given it an edge over other low-lying parts of the world.

The regional Water Boards, some founded in the 13th century, are independent from national government, allowing them to plan beyond the length of political cycles. Policymakers have forged strong ties to the scientific community, and there is close collaboration across institutions.

But major flood works have often been reactive, prompted by disasters such as the 1953 storm that breached the dikes and flooded almost a tenth of Dutch farmland. The disaster killed 1,836 people, destroyed homes and drowned tens of thousands of animals.

Now, the Dutch government is trying to get ahead of the curve.

This year, it commissioned a group of experts, the Sea Level Rise Knowledge Programme, to monitor the issue and map out potential responses. The group is working with four scenarios, according to Marjolijn Haasnoot, an environmental scientist at the research institute Deltares and Utrecht University, who has led the development of future scenario planning in the Netherlands.

Once rich farmland, Noordwaard is now an expanse of reedy marshlands in the southwest, deliberately designed to flood in order to keep nearby Dutch cities dry | Sijmen Hendriks/Hollandse Hoogte

Two of the scenarios — called “Protect Open” and “Protect Closed” — involve ramping up defenses with existing tools, with the option of having storm barriers either open or closed. The third, “Advance,” is an attack scenario, in which the Netherlands reclaims additional land from the sea and builds islands on it.

“Accommodate” is about retreat — identifying which parts of the Netherlands can be retained, and which should be given back to the sea to save the rest. The plan would involve building dikes and pumping out water, as well as creating deliberate floodplains. Some buildings could be built to float; homes could be erected on stilts and terps, a traditional mound used in antiquity.

To help choose the best approach in preparing for a still uncertain future, Haasnoot has developed a model that maps out potential future scenarios and determines what actions should be taken in response to each one.

She does not expect retreat to be necessary in the next 100 years, but warned that some of the other options, while technically feasible, would be disruptive. Raising dikes, lowering the level of acceptable flood risk, increasing pumping, and shutting the storm barriers, for example, all come with costs and trade-offs.

She also warned that what's coming might go beyond anything the Dutch have handled before. "There is this possibility that the sea level may rise much faster after 2050, and we need to take a lot of actions in a very short time,” Haasnoot said. “Some of the actions might be very large. We don't have experience of that."

Roadblocks
Scientists say they find the risks posed by sea level rise hard to convey to the public but insist it’s important to keep trying. It's politically difficult, they say, because it requires making sacrifices now for an uncertain and far-flung future.

“Even if it's far in the future, the implications are so high and the challenge to manage the delta is so large," said Haasnoot. “We cannot wait until we experience the effects to act.”

The Netherlands is set to miss its target to reduce emissions by 30 percent by 2020 compared to 1990 levels. This summer, seven political parties from the left and right banded together to pass a climate change law aimed at slashing emissions by 95 percent by 2050. But attempts to follow up with action have been met with fierce lobbying from those affected.

Dutch farmers blockaded cities across the Netherlands with their tractors in October in protest against government efforts to curb nitrogen pollution, which is largely caused by the farming and construction industries.

"We spend a lot of money in Holland on water management. We have to do it because if we don't, we will be flooded" — Stan Fleerakkers, dairy farmer

The army was brought in to defend The Hague, and four regional governments suspended the measures under the pressure. This was followed by similar protests by construction workers with trucks and diggers that caused traffic jams stretching 380 kilometers, according to the traffic authority ANWB.

“This will have repercussions for many decades and centuries. It takes a very brave politician to take on,” said Utrecht University’s van den Broeke. “There is still a significant part of the Dutch population that is not aware or not interested in these problems, so it does require strong leadership to make these changes.”

Kleinhans, the physical geography professor, believes that the prevalent sense of security and confidence about flood defenses among the wider population is misplaced.

“It’s a belief based on the past,” Kleinhans said. “We're facing something worse than ever in human history, and perhaps in geological history. We've never had this kind of challenge, and we're not ready for it.”

Room for the water
Ultimately, however, the Netherlands may have no other option than to adapt, or possibly retreat. A group of farmers at the Overdiepse Polder — not far from the evacuated Noordwaard marshlands — demonstrates the limits of the Dutch model.

It was a small article in a local newspaper that first alerted Stan Fleerakkers and his fellow 15 farmers that their land was listed for inclusion in the Room for the River program, a response to the Rhine floods of 1995, in which 250,000 people had to be evacuated.

“We knew if we are going to fight the government, we are going to lose,” recalled Fleerakkers. “We decided we are going to cooperate with the government, and make it our plan. We want to stay here, we want to farm, we want to expand.”

Rather than leave, half the farmers convinced the authorities to help them stay. The result is certainly a feat of engineering and planning. The farmers now live in large, Scandinavian-chic farmhouses, newly-built on terps elevated six meters above their meadow lands, and linked to the nearest village by roads raised at the same height. In winter, they move their cattle up into their elevated barns.

Beachcombers soak up the sun on Scheveningen, in the Hague. The Netherlands must constantly replenish the sand on its beaches due to rapidly rising sea levels | Sem van der Wal/AFP via Getty Images

The tradeoff for remaining is that their land now doubles as a basin designed to deliberately flood to save the nearby urban centers of Waalwijk and 's-Hertogenbosch. The dike at the end of their fields, beyond which container ships pass along the river Maas, was deliberately lowered to usher in the river water when it exceeds a certain point. It is expected to flood once every 25 years, and to flood seriously twice a century.

The question is whether that approach is scalable as sea levels continue to rise. The relocation of the Overdiepse farmers took place in a time of luxury, both of funds and of time. To move just 16 farmers took from 1999 to 2015. Every step of the process was oiled with money.

The government bought Fleerakkers' old farm at a generous price. He remained living and working on it while the government built the terp and dyke works for his new home. If a flood ever occurs outside of winter months, he is guaranteed compensation for any damages and lost crops. He also has an agreement that the government will buy his farm, at the price of farms not located in floodlands, should he ever choose to move.

"It's not as expensive as when a village is flooded," said Fleerakkers. "We spend a lot of money in Holland on water management. We have to do it because if we don't, we will be flooded — no factories, no people who live here, it will all be gone."

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