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Can these giant dams keep Europe from drowning?
Why a 400-mile enclosure around the North Sea is not as crazy as it sounds

Proposal for the Northern European Enclosure Dam (NEED), in two main parts: from France to England, and from Scotland to Norway.
- The Northern European Enclosure Dam (NEED) would cut off the North and Baltic Seas from the Atlantic Ocean.
- It would save 15 countries, and up to 55 million people, from sea level rise—but at a cost.
- The idea is a warning more than a plan: NEED will be necessary if we don't stop global warming now.
Unprecedented scale
The top of a 4.5-m (15-ft) statue, some rooftops and a church spire are all that remains above water in Wieringerwerf, near Amsterdam, during the Wieringermeer flood of 1945.
Image: Nationaal Archief / Willem van de Poll / Anefo – CC0 1.0
Climate change is real, and it's bad. It's also gradual and impersonal. That's why it's both tempting and easy to stick your head in the sand. Do that long enough, though, and you're likely to drown, as sea level rise (SLR) catches up with you.
Here's something that might shock you into action: A plan for a giant dam to protect 15 European countries from those rising seas. The project's scale is unprecedented. Its cost phenomenal. But it's still cheaper than all the alternatives—including doing nothing. All the alternatives except one: Taking action now against climate change.
Here's how the situation looks today:
- Current global mean temperature is about 1°C (1.8°F) above pre-industrial levels.
- Rising temperatures cause rising sea levels, albeit with a lag. Global mean SLR is 18 cm (7 in) since 1880 and it's accelerating.
- Current policies imply a further global warming of up to 3.1 °C (5.6°F) by 2100, so it's virtually certain SLR will continue well beyond that date.
- The rule of thumb: For every extra °C, expect an SLR of 2.3 m (7.5 ft). Because of the lagging effect, SLR by 2100 would be 'only' 1 to 2 m (3.3 to 6.6 ft). But by 2500, it could be as high as 10 m (32.8 ft).
51 billion tons of sand
Total length: Almost 400 miles. Total cost: Up to $600 billion. PInk dots: Areas with high population density.
Image: Groeskamp & Kjellsson
The logistics of their proposal are dizzying:
- NEED would consist of two major sections: NEED-South, a dam connecting France's Breton coast (near Brest) with England's south-west coast. It would measure 161 km (100 mi) in length, with an average depth of 85 m (279 ft) and a maximum depth of 102 m (335 ft).
- NEED-North would consist of several parts, linking the Scottish mainland to the Orkney and Shetland Islands, and from there to Norway. Its total length would be 476 km (296 mi), with an average depth of 127 m (417 ft) and a maximum depth of 321 m (1,053 ft) in the Norwegian Trench.
- NEED would have a combined length of 637 km (396 mi).
- NEED would have a combined volume of 36.2 km3 (8.7 mi3), which would require 51 billion tons of sand. That is equal to one year's worth of global sand use.
- Total price for NEED: Somewhere between €250-€550 billion ($270-$600 bn).
- NEED would protect coastal communities in 15 countries, keeping the feet dry of 25 million to 55 million people; depending on SLR of between 2 to 15 m (6.6 to 49.2 ft), respectively.
Cheapest option
What would happen to the Netherlands if the sea level rose by 1.8 m (6 ft): The blue area would flood.
Image: Rijksuniversiteit Groningen
So, how do those alternatives pan out, exactly?
Since so much of most countries' population and economies is located at or near the coast, the cost of doing nothing is extreme: Up to 10 times as high as the main alternatives, protection and retreat. Being scientists rather than politicians, Groeskamp and Kjellsson only considered the latter two.
- Managed retreat is a feasible option and is indeed being implemented in the Netherlands, for example, on a small scale. But large-scale retreat for SLR would involve forced migration of large numbers of people, widespread psychological trauma, massive loss of cultural heritage, and political instability at an international level.
- The combined cost of protection on a per-country basis would soon dwarf the cost of NEED. Again, the Dutch example. In a scenario of 1.5 m (4.9 ft) SLR by 2100, the Netherlands would need to spend up to €140 billion ($152 bn) on sea defenses. That alone amounts to about one-third of the total cost of NEED.
- Spread out over 20 years, its cost would amount to at most 0.16% of the combined GDP of the 15 countries involved.
- Even if the cost were borne by the five local countries most likely affected by SLR (the UK, the Netherlands, Belgium, Denmark and Germany), it would still only amount to 0.32% of their combined GDP, tops.
Serious consequences
Some other parts of the world where solutions similar to NEED could help safeguard coastal areas from sea level rise.
Image: Groeskamp & Kjellsson
They are not presenting NEED as a panacea, however. Blocking off the North and Baltic Seas from the Atlantic Ocean will have far-reaching, and potentially serious consequences for the region's ecosystems, economies and societies.
- Rivers will continue to discharge into the enclosed seas, and this alone will lead to an annual SLR of 0.9 m (3 ft). Around 100 major pumping stations would be needed to transfer that volume to the ocean.
- The continued discharge would also lead to a freshening of the basin, with salinity projected to reduce by a factor 10 over the course of a century. This would greatly affect biodiversity and fishing.
- The damming of the North Sea would produce important changes in the tidal amplitudes, on both sides of NEED. Inside, it would be greatly reduced. Outside, it would increase by up to 0.7 m (2.3 ft) along the coasts of Wales and southwest England. This would have a major effect on the circulation of sediment, nutrients and small marine life in the area.
- NEED would lock Europe's four busiest ports—Rotterdam, Antwerp, Bremerhaven, Hamburg—behind a huge dam. New harbors would need to be built on the exterior of the dams, and/or sluices to accommodate the volume of traffic to the interior ports.
'NEED – The Northern European Enclosure Dam for if climate change mitigation fails' by Sjoerd Groeskamp and Joakim Kjellsson, was published in the January 2020 Bulletin of the American Meteorological Society. Read it in full here. Image of Wieringermeer flood found here on Wikimedia Commons. Map of Netherlands flooding found here at Oog TV.
Strange Maps #1012
Got a strange map? Let me know at strangemaps@gmail.com.
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Weird science shows unseemly way beetles escape after being eaten
Certain water beetles can escape from frogs after being consumed.
R. attenuata escaping from a black-spotted pond frog.
- A Japanese scientist shows that some beetles can wiggle out of frog's butts after being eaten whole.
- The research suggests the beetle can get out in as little as 7 minutes.
- Most of the beetles swallowed in the experiment survived with no complications after being excreted.
In what is perhaps one of the weirdest experiments ever that comes from the category of "why did anyone need to know this?" scientists have proven that the Regimbartia attenuata beetle can climb out of a frog's butt after being eaten.
The research was carried out by Kobe University ecologist Shinji Sugiura. His team found that the majority of beetles swallowed by black-spotted pond frogs (Pelophylax nigromaculatus) used in their experiment managed to escape about 6 hours after and were perfectly fine.
"Here, I report active escape of the aquatic beetle R. attenuata from the vents of five frog species via the digestive tract," writes Sugiura in a new paper, adding "although adult beetles were easily eaten by frogs, 90 percent of swallowed beetles were excreted within six hours after being eaten and, surprisingly, were still alive."
One bug even got out in as little as 7 minutes.
Sugiura also tried putting wax on the legs of some of the beetles, preventing them from moving. These ones were not able to make it out alive, taking from 38 to 150 hours to be digested.
Naturally, as anyone would upon encountering such a story, you're wondering where's the video. Thankfully, the scientists recorded the proceedings:
The Regimbartia attenuata beetle can be found in the tropics, especially as pests in fish hatcheries. It's not the only kind of creature that can survive being swallowed. A recent study showed that snake eels are able to burrow out of the stomachs of fish using their sharp tails, only to become stuck, die, and be mummified in the gut cavity. Scientists are calling the beetle's ability the first documented "active prey escape." Usually, such travelers through the digestive tract have particular adaptations that make it possible for them to withstand extreme pH and lack of oxygen. The researchers think the beetle's trick is in inducing the frog to open a so-called "vent" controlled by the sphincter muscle.
"Individuals were always excreted head first from the frog vent, suggesting that R. attenuata stimulates the hind gut, urging the frog to defecate," explains Sugiura.
For more information, check out the study published in Current Biology.
The cost of world peace? It's much less than the price of war
The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
- Conflict and violence cost the world more than $14 trillion a year.
- That's the equivalent of $5 a day for every person on the planet.
- Research shows that peace brings prosperity, lower inflation and more jobs.
- Just a 2% reduction in conflict would free up as much money as the global aid budget.
- Report urges governments to improve peacefulness, especially amid COVID-19.
What is the price of peace?
Or put another way, how much better off would we all be in a world where armed conflict was avoided?
Around $14.4 trillion in 2019, according to the Institute for Economics and Peace (IEP) which crunched the numbers. That's about $5 a day for every person on the planet.
To give some context, 689 million people - more than 9% of the world's population - live on less than $1.90 a day, according to World Bank figures, underscoring the potential impact peace-building activities could have.
Just over 10% of global GDP is being spent on containing, preventing and dealing with the consequences of violence. As well as the 1.4 million violent deaths each year, conflict holds back economic development, causes instability, widens inequality and erodes human capital.
Putting a price tag on peace and violence helps us see the disproportionately high amounts spent on creating and containing violent acts compared to what is spent on building resilient, productive, and peaceful societies.
—Steve Killelea, founder and executive chairman, Institute for Economics & Peace (IEP)
The cost of violence
In a report titled "The Economic Value of Peace 2021", the IEP says that for every death from violent conflict, 40 times as many people are injured. The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
Grounds for hope
But the picture is not all bleak. The economic impact of violence fell for the second year in a row in 2019, as parts of the world became more peaceful.
The global cost dropped by $64 billion between 2018 and 2019, even though it was still $1.2 trillion higher than in 2012.
In five regions of the world the costs increased in 2019. The biggest jump was in Central America and the Caribbean, where a rising homicide rate pushed the cost up 8.3%.
Syria, with its ongoing civil war, suffered the greatest economic impact with almost 60% of its GDP lost to conflict in 2019. That was followed by Afghanistan (50%) and South Sudan (46%).
The report makes a direct link between peace and prosperity. It says that, since 2000, countries that have become more peaceful have averaged higher GDP growth than those which have become more violent.
"This differential is significant and represents a GDP per capita that is 30% larger when compounded over a 20-year period," the report says adding that peaceful countries also have substantially lower inflation and unemployment.
"Small improvements in peace can have substantial economic benefits," it adds. "For example, a 2% reduction in the global impact of violence is roughly equivalent to all overseas development aid in 2019."
Equally, the total value of foreign direct investment globally only offsets 10% of the economic impact of violence. Authoritarian regimes lost on average 11% of GDP to the costs of violence while in democracies the cost was just 4% of GDP.
And the gap has widened over time, with democracies reducing the cost of violence by almost 16% since 2007 while in authoritarian countries it has risen by 27% over the same period.
The report uses 18 economic indicators to evaluate the cost of violence. The top three are military spending (which was $5.9 trillion globally in 2019), the cost of internal security which makes up over a third of the total at $4.9 trillion and homicide.
Peace brings prosperity
The formula also contains a multiplier effect because as peace increases, money spent containing violence can instead be used on more productive activities which drive growth and generate higher monetary and social returns.
"Substantial economic improvements are linked to improvements in peace," says the report. "Therefore, government policies should be directed to improving peacefulness, especially in a COVID-19 environment where economic activity has been subdued."
The IEP says what it terms "positive peace" is even more beneficial than "negative peace" which is simply the absence of violence or the fear of violence. Positive peace involves fostering the attitudes, institutions & structures that create and sustain peaceful societies.
The foundations of a positively peaceful society, it says, are: a well functioning government, sound business environment, acceptance of the rights of others, good relations with neighbours, free flow of information, high levels of human capital, low levels of corruption and equitable distribution of resources.
The World Economic Forum's report Mobilizing the Private Sector in Peace and Reconciliation urged companies large and small to recognise their potential to work for peace quoting the former Goldman Sachs chair, the late Peter Sutherland, who said: "Business thrives where society thrives."
Reprinted with permission of the World Economic Forum. Read the original article.
The evolution of modern rainforests began with the dinosaur-killing asteroid
The lush biodiversity of South America's rainforests is rooted in one of the most cataclysmic events that ever struck Earth.
Velociraptor Dinosaur in the Rainforest
- One especially mysterious thing about the asteroid impact, which killed the dinosaurs, is how it transformed Earth's tropical rainforests.
- A recent study analyzed ancient fossils collected in modern-day Colombia to determine how tropical rainforests changed after the bolide impact.
- The results highlight how nature is able to recover from cataclysmic events, though it may take millions of years.
About 66 million years ago, a massive asteroid slammed into present-day Chicxulub, Mexico, triggering the extinction of dinosaurs. Scientists estimate the impact killed 75 percent of life on Earth. But what's remained more mysterious is how the event shaped the future of plant life, specifically tropical rainforests.
A new study published in Science explores how the so-called bolide impact at the end of the Cretaceous period paved the way for the evolution of our modern rainforests, the most diverse terrestrial ecosystems on Earth.
For the study, researchers analyzed thousands of samples of fossil pollen, leaves, and spores collected from various sites across Colombia. The researchers analyzed the samples to determine which types of plants were dominant, the diversity of plant life, and how insects interacted with plants.
All samples dated back to the Cretaceous-Paleogene boundary, some 70 million to 56 million years ago. Back then, the region's climate was mostly humid and hot, as it is today. However, the composition and structure of forests were quite different before the impact, according to the study results.
Tropical jungle with river and sun beam and foggy in the gardenSASITHORN via Adobe Stock
For one, the region's rainforests used to have a roughly equal mix of angiosperms (shrubs and flowering trees) and plants like conifers and ferns. The rainforests also had a more open canopy structure, which allowed more light to reach the forest floor and meant that plants faced less competition for light.
What changed after the asteroid hit? The results suggest the impact and its aftermath led to a 45 percent decrease in plant diversity, a loss from which the region took about 6 million years to recover. But different plants came to replace the old ones, with an increasing proportion of flowering plants sprouting up over the millennia.
"A single historical accident changed the ecological and evolutionary trajectory of tropical rainforests," Carlos Jaramillo, study author and paleopalynologist at the Smithsonian Tropical Research Institute in Panama City, told Science News. "The forests that we have today are really the by-product of what happened 66 million years ago."
Today's rainforests are significantly more biodiverse than they were 66 million years ago. One potential reason is that the more densely packed canopy structure of the post-impact era increased competition among plants, "leading to the vertical complexity seen in modern rainforests," the researchers wrote.
The extinction of long-necked, leaf-eating dinosaurs probably helped maintain this closed-canopy structure. Also boosting biodiversity was ash from the impact, which effectively fertilized the soil by adding more phosphorus. This likely benefited flowering plants over the conifers and ferns of the pre-impact era.
In addition to unraveling some of the mysteries about the origins of South America's lush biodiversity, the findings highlight how, even though life finds a way to recover from catastrophe, it can take a long time.
New study determines how many mothers have lost a child by country
Global inequality takes many forms, including who has lost the most children
