Kill dates of black mosses are archives of Antarctic glacier history

Credit: coolantarctica.com

Natural climate variation is and always has been an ongoing process in Antarctica, just like everywhere else. Research suggests conditions similar to recent years prevailed about 850 years ago in at least one region.
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Mosses, one of the few types of plants living in Antarctica, have a tenuous existence, threatened by advancing glaciers, says the U.S. National Science Foundation.

When glaciers move, they can entomb or cover a plant — starving it of light and warmth. Scientists have discovered that the timing of when a glacier killed a moss, the kill date, provides an archive of glacier history.

The date the plant died coincides with the time the glacier advanced over that location. As glaciers recede, the previously entombed mosses are exposed, now dead and black.

What Climate Crisis? A Primer On Earth’s Turbulent Climatic Past

Ross Ice Shelf, Antarctica

Blinkered climate obsessives, from protesters to governments, need to wise up about their pet topic. Professor Ian Plimer offers some assistance to trace gas worriers.
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For more than 80 percent of the time, Earth has been a warm wet greenhouse planet with no ice, says Ian Plimer at Spectator AU (via Climate Change Dispatch.

We live in unusual times when ice occurs on continents. This did not happen overnight.

The great southern continent, Gondwanaland, formed about 550 million years ago. It occupied 20 percent of the area of our planet and included Antarctica, South America, Australia, South Africa, and the Indian subcontinent.

Gondwanaland was covered by ice when it drifted across the South Pole 360-255 million years ago. Evidence for this ice age is in the black coal districts of Australia, South Africa, and India.

Bering Land Bridge formed surprisingly late during last ice age, say researchers

Credit: alaskapublic.org

A researcher said: “Remarkably, the data suggest that the ice sheets can change in response to more than just global climate,” calling into question some long-held ideas. A professor connected to the study commented: “These findings appear to poke a hole in our current understanding of how past ice sheets interacted with the rest of the climate system, including the greenhouse effect.” Well, fancy that. The commentary notes that ‘global temperatures were relatively stable at the time of the fall in sea level, raising questions about the correlation between temperature, sea level and ice volume’. In short, the ice sheets grew faster than scientists had thought.
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Princeton scientists found that the Bering Land Bridge, the strip of land that once connected Asia to Alaska, emerged far later during the last ice age than previously thought, says Eurekalert. 

The unexpected findings shorten the window of time that humans could have first migrated from Asia to the Americas across the Bering Land Bridge. 

The findings also indicate that there may be a less direct relationship between climate and global ice volume than scientists had thought, casting into doubt some explanations for the chain of events that causes ice age cycles.

The study was published on December 27 in the Proceedings of the National Academy of Sciences.

“This result came totally out of left field,” said Jesse Farmer, postdoctoral researcher at Princeton University and co-lead author on the study. “As it turns out, our research into sediments from the bottom of the Arctic Ocean told us not only about past climate change but also one of the great migrations in human history.”

Insight into ice age cycles

During the periodic ice ages over Earth’s history, global sea levels drop as more and more of Earth’s water becomes locked up in massive ice sheets.

At the end of each ice age, as temperatures increase, ice sheets melt and sea levels rise. These ice age cycles repeat throughout the last 3 million years of Earth’s history, but their causes have been hard to pin down.

By reconstructing the history of the Arctic Ocean over the last 50,000 years, the researchers revealed that the growth of the ice sheets — and the resulting drop in sea level — occurred surprisingly quickly and much later in the last glacial cycle than previous studies had suggested.

“One implication is that ice sheets can change more rapidly than previously thought,” Farmer said.

During the last ice age’s peak of the last ice age, known as the Last Glacial Maximum, the low sea levels exposed a vast land area that extended between Siberia and Alaska known as Beringia, which included the Bering Land Bridge. In its place today is a passage of water known as the Bering Strait, which connects the Pacific and Arctic Oceans.

Based on records of estimated global temperature and sea level, scientists thought the Bering Land Bridge emerged around 70,000 years ago, long before the Last Glacial Maximum.

But the new data show that sea levels became low enough for the land bridge to appear only 35,700 years ago. This finding was particularly surprising because global temperatures were relatively stable at the time of the fall in sea level, raising questions about the correlation between temperature, sea level and ice volume.

“Remarkably, the data suggest that the ice sheets can change in response to more than just global climate,” Farmer said. For example, the change in ice volume may have been the direct result of changes in the intensity of sunlight that struck the ice surface over the summer.

“These findings appear to poke a hole in our current understanding of how past ice sheets interacted with the rest of the climate system, including the greenhouse effect,” said Daniel Sigman, Dusenbury Professor of Geological and Geophysical Sciences at Princeton University and Farmer’s postdoctoral advisor.

“Our next goal is to extend this record further back in time to see if the same tendencies apply to other major ice sheet changes. The scientific community will be hungry for confirmation.”

Full article here.
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Study: The Bering Strait was flooded 10,000 years before the Last Glacial Maximum

What may be the largest source of abiotic methane gas on Earth

Natural gas flare [credit: Wikipedia]

abiotic — Not associated with or derived from living organisms. Calling methane, aka natural gas, a ‘fossil fuel’ is shown by geological evidence to be inaccurate.
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Methane (CH4), the chief constituent of natural gas, is one of the most widely used “clean” fuels, says Phys.org.

Although methane is usually considered to originate from organic matter, recently, more and more evidence shows that methane can be produced by abiotic processes.

In a recent paper published in National Science Review (NSR), Professor Lifei Zhang’s team from Peking University demonstrated that large amounts of methane gas can form during prograde metamorphism in a cold subduction zone, evidenced by the massive CH4-rich fluid inclusions in eclogites from Western Tianshan, China.

Earth can regulate its own temperature over millennia, new study finds

This schematic shows the relationship between the different physical and chemical processes that make up the carbonate-silicate cycle. In the upper panel, the specific processes are identified, and in the lower panel, the feedbacks associated are shown; green arrows indicate positive coupling, while yellow arrows indicate negative coupling [image credit: Gretashum @ Wikipedia]

There’s always been a carbonate–silicate cycle, which Wikipedia declares ‘is the primary control on carbon dioxide levels over long timescales’. Warmists have shoe-horned this into their atmospheric theories, as we can see from the appearance of ‘greenhouse effect’ in the graphic above. Carry on, Earth.
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The Earth’s climate has undergone some big changes, from global volcanism to planet-cooling ice ages and dramatic shifts in solar radiation, says Eurekalert.

And yet life, for the last 3.7 billion years, has kept on beating.

Now, a study by MIT researchers in Science Advances confirms that the planet harbors a “stabilizing feedback” mechanism that acts over hundreds of thousands of years to pull the climate back from the brink, keeping global temperatures within a steady, habitable range.

Just how does it accomplish this?

Faster in the Past: New seafloor images of West Antarctic Ice Sheet upend understanding of Thwaites Glacier retreat

Some like to call it the Doomsday Glacier. The research results are probably open to a variety of interpretations, in terms of predictions. But we’re told that whatever is being observed at present is by no means exceptional, making attempts at attribution of its ever-changing condition to human activity even more problematic. Volcanic activity is an obvious confounding factor here.
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The Thwaites Glacier in West Antarctica — about the size of Florida — has been an elephant in the room for scientists trying to make global sea level rise predictions, says Science Daily.

This massive ice stream is already in a phase of fast retreat (a “collapse” when viewed on geological timescales) leading to widespread concern about exactly how much, or how fast, it may give up its ice to the ocean.

The potential impact of Thwaites’ retreat is spine-chilling: a total loss of the glacier and surrounding icy basins could raise sea level from three to 10 feet.

‘We are not ready’: Divisions deepen over rush to finalise deep sea mining rules

Seabed mining

The ‘energy transition’ is supposed to replace thousands of coal-fired power stations and over a hundred million barrels of oil per year, amongst other fuels like gas and wood, in the name of an invented ‘climate crisis’. Not going to happen on the scale required, even if this new supply of minerals were to become available – with the aid of fossil fuel powered machinery. All that mining will, or would be, waste product one day.
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A growing number of countries are demanding more time to decide on rules that would allow companies to mine the deep seabed for minerals needed to manufacture batteries for the energy transition, says Climate Change News.

Last year, the small island state of Nauru, triggered a never-before-used procedure giving the International Seabed Authority (ISA), the UN body which regulates mining activities in international waters, until July 2023 to fast-track deep sea mining exploitation rules.

Countries have discussed mining the bottom of the oceans for years but no commercial extraction has started in international waters. The ultimatum would allow the nascent industry to apply for mining permits as soon as next year.

Ancient ‘megafloods’ tilted the very direction of Earth’s crust, scientists find

Image credit: NASA

Ice age flooding, recreated in models.
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Earth’s last major ice age locked up gargantuan amounts of water in vast glaciers, says Science Alert.

Once they melted, it was a spectacle to behold as tremendous floods gouged channels into the face of the planet.

The remnants of one of the largest of these ancient deluges are still visible in eastern Washington, in an area now known as the Channeled Scablands.

For a long time, geologists have been struggling to understand the dynamic properties of these floods, until a recent key insight was made.

These ancient glaciers were so large and heavy, they actually tilted Earth’s crust beneath them – when weight was released due to melting, the land would have moved too, changing the course of the megaflood.

Using modeling of ancient megafloods, researchers decided to test whether glacial isostatic adjustment (GIA) – deflections in the crust as heavy chunks of ice form and melt – would affect the routing flow and erosion in two prominent Scabland tracks.

“We used relatively simple, yet plausible, numerical experiments to test whether GIA could have had a substantial impact on flood routing and erosion for two major scabland tracts, Cheney-Palouse and Telford-Crab Creek,” write the authors of the study.

“To this end, we modeled GIA to reconstruct the topography of the Channeled Scabland at different times during the period of Ice Age flooding.”

Up until now, reconstructions of ancient megaflood routing had investigated how other variables would affect them – things like erosion and the movement of sediment, the three-dimensional mechanics of the environment, or how ice dams break, for example.

But they would also base these reconstructions on present-day topography, approximating how past landscapes may have looked.

“People have been looking at high water marks and trying to reconstruct the size of these floods, but all of the estimates are based on looking at the present-day topography,” said lead author Tamara Pico, assistant professor of Earth and planetary sciences at UC Santa Cruz.

Geologists realized that the effects melting glaciers were having on Earth’s crust were also likely playing a role in the routing and behavior of these megafloods.

“GIA caused crustal deformation in the Channeled Scabland with rates up to 10 millimeters per year, orders of magnitude above regional tectonic uplift rates and, therefore, may have influenced flood routing,” note the authors.

“The course of ancient, glacial outburst floods was likely influenced by glacial isostatic adjustment (GIA), and reconstructing these events informs our understanding of how floods shape landscapes on Earth and Mars,” they added.
. . .
The researchers believe the deformation of Earth’s crust due to the expanding and contacting of the ice sheets would have altered the elevation of the landscape by hundreds of meters over this period.

Moving forward, the researchers want to simulate past megaflood events which incorporate the multiple factors that determine their routing.

However, understanding the important role that ice age crustal deformation plays during flood routing and erosion in these ancient megafloods is a step in the right direction.

Full article here.

Tug of sun, moon could be driving plate motions on ‘imbalanced’ Earth, suggest researchers

Credit: reference.com

Plate tectonics has always been good for a science controversy or two. This one throws some solar-planetary spice into the mix, putting a focus on the Earth-Moon barycentre.
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A study led by geophysicist Anne M. Hofmeister in Arts & Sciences at Washington University in St. Louis proposes that imbalanced forces and torques in the Earth-moon-sun system drive circulation of the whole mantle, says Phys.org.

The new analysis provides an alternative to the hypothesis that the movement of tectonic plates is related to convection currents in the Earth’s mantle.

Convection involves buoyant rise of heated fluids, which Hofmeister and her colleagues argue does not apply to solid rocks.

They argue that force, not heat, moves large objects.

Climate-friendly farming: Greenland’s melting glaciers offer an answer

Greenland drink break [image credit: leisurelylifestyle.com]

As a bonus in today’s climate obsessed times, carbon credits could come into play for farmers to sell with this discovery. Even Danish brewers can benefit. Why fear glacier melt if it makes life better?
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On a shore near Greenland’s capital Nuuk, a local scientist points to a paradox emerging as the island’s glaciers retreat: one of the most alarming consequences of global warming could deliver a way to limit its effects, says Reuters (via Yahoo News).

“It’s a kind of wonder material,” says Minik Rosing, a native Greenlander, referring to the ultra-fine silt deposited as the glaciers melt.

Known as glacial rock flour, the silt is crushed to nano-particles by the weight of the retreating ice sheet, which deposits roughly one billion tonnes of it on the world’s largest island per year.

Professor Minik Rosing and his team at the University of Copenhagen have established the nutrient-rich mud boosts agricultural output when applied to farmland and absorbs carbon dioxide from the air in the process.

Earth Tipped on Its Side 84 Million Years Ago, New Evidence Suggests

Diagram showing solid-body rotation of the Earth with respect to a stationary spin axis due to true polar wander. [Credit: Wikipedia]

The researchers say their finding ‘challenges the notion that the spin axis has been largely stable over the past 100 million years.’
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We know that true polar wander (TPW) can occasionally tilt whole planets and moons relative to their axes, but it’s not entirely clear just how often this has happened to Earth, says ScienceAlert.

Now a new study presents evidence of one such tilting event that occurred around 84 million years ago – when dinosaurs still walked the Earth.

Researchers analyzed limestone samples from Italy, dating back to the Late Cretaceous period (100.5 to 65.5 million years ago), looking for evidence of shifts in the magnetic record that would point towards an occurrence of TPW.

Bacteria fossils trapped in the rock, forming chains of the mineral magnetite, offer some of the most convincing evidence yet of true polar wander in the Late Cretaceous – and it may help settle a scientific debate that’s been going on for decades.

Iceland’s volcanic eruption the longest in half a century

A local expert comments: “There seems to be still enough magma from whatever reservoir the eruption is tapping. So it could go on for a long time.”
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It will be six months on Sunday that the volcanic eruption currently mesmerising spectators near Reykjavik first began, making it the longest Iceland has witnessed in more than 50 years, says Phys.org.

The first lava began spewing out of a fissure close to Mount Fagradalsfjall on the evening of March 19 on the Reykjanes peninsula to the southwest of Reykjavik.

And the ensuing spectacle—ranging from just a slow trickle of lava at times to more dramatic geyser-like spurts of rocks and stones at others—has become a major tourist attraction, drawing 300,000 visitors so far, according to the Iceland Tourist Board.

Iceland’s sixth volcanic eruption in 20 years is already longer than the preceding one in Holuhraun, in the centre-east of the island, which lasted from the end of August 2014 until the end of February 2015.

‘Icelandia’: Is Iceland the tip of a vast, sunken continent?

Evidence for plate divergence in Iceland [image credit: Rob Young @ Wikipedia]

There could be more to Iceland than meets the eye. A lot more, if these theorists are right.
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Academics believe they have identified a remarkable geological secret: A sunken continent hidden under Iceland and the surrounding ocean, which they have dubbed “Icelandia”, says Phys.org.

Academics believe they have identified a remarkable geological secret: A sunken continent hidden under Iceland and the surrounding ocean, which they have dubbed “Icelandia.”

An international team of geologists, led by Gillian Foulger, Emeritus Professor of Geophysics in the Department of Earth Sciences at Durham University (UK), believe the sunken continent could stretch from Greenland all the way to Europe.

It is believed to cover an area of ~600,000 km2 but when adjoining areas west of Britain are included in a “Greater Icelandia,” the entire area could be ~1,000,000 km2 in size.

If proven, it means that the giant supercontinent of Pangaea, which is thought to have broken up over 50 million years ago, has in fact not fully broken up.

The 27.5-million-year cycle of geological activity

Scientists previously proposed 26 million year cycles of mass extinctions, but this appears to correct the period. They suggest ‘cycles of activity in the Earth’s interior’ could be behind their new period, but then say: ‘However, similar cycles in the Earth’s orbit in space might also be pacing these events.’ Their study also says ‘a strong secondary signal occurs at a period 8.9 Myr’.
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Geologic activity on Earth appears to follow a 27.5-million-year cycle, giving the planet a ‘pulse,’ according to a new study published in the journal Geoscience Frontiers. Phys.org reporting.

“Many geologists believe that geological events are random over time. But our study provides statistical evidence for a common cycle, suggesting that these geologic events are correlated and not random,” said Michael Rampino, a geologist and professor in New York University’s Department of Biology, as well as the study’s lead author.

Over the past five decades, researchers have proposed cycles of major geological events—including volcanic activity and mass extinctions on land and sea—ranging from roughly 26 to 36 million years.

But early work on these correlations in the geological record was hampered by limitations in the age-dating of geologic events, which prevented scientists from conducting quantitative investigations.

Iceland: could a volcanic period be ahead?

Lava fields of the Reykjanes Peninsula [image credit: Vincent van Zeijst @ Wikipedia]

24th February: ‘Southwestern Iceland was rocked by a series of earthquakes’, reported DW.com. ‘Experts say shocks from the quake, which registered 5.7 in magnitude, sparked increased volcanic activity, triggering a number of aftershocks registering over 4.0 for hours after the initial quake hit.

“It’s an intense activity zone, we are all well aware of that but I’ve never experienced or felt so many strong earthquakes in such a short period of time. It’s unusual,” as the Icelandic Meteorological Office’s (IMO) earthquake hazards coordinator Kristin Jonsdottir told Icelandic public broadcaster RUV.’

The article below appeared five days ago.
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“If an eruption occurs, it would likely mark the beginning of such a [volcanic] period – lasting a few centuries, I believe,” states Magnús Á. Sigurgeirsson, geologist at ÍSOR Iceland GeoSurvey – a consulting and research institute in the field of geothermal sciences and utilization.

“That’s at least how it has been the past three times, and even dating further back, but we don’t have as exact data available on that,” he tells Iceland Monitor.

He is referring to the uncertainty regarding whether an eruption can be expected soon on the Reykjanes peninsula, Southwest Iceland.

Magnús assembled data on the past three volcanic periods in the area. These were 3,000-3,500 years ago, 1,900-2,400 years ago, and finally between the years 800 and 1240 AD.

His information is based on geological maps of the Reykjanes peninsula and on a comprehensive book on volcanic eruptions in Iceland called Nátt­úru­vá á Íslandi, eld­gos og jarðskjálft­ar.

Research reveals that during the latter part of Holocene – a term used to describe a period that began about 11,700 years ago – the volcanic systems on the Reykjanes peninsula have erupted every 900 to 1100 years.

Less is known about the first part of Holocene.

Each eruption period appears to have lasted about 500 years, and during that time most of the volcanic systems appear to have been active, albeit generally not simultaneously. The volcanic activity is characterized by eruptions that each last a few decades. Lava flows from volcanic fissures that can be as long as 12 km (7.5 mi).

On the Reykjanes peninsula, there are six volcanic systems, lined up side by side, pointing from southwest to northeast. Farthest west is that of Reykjanes, then those of Svartsengi, Fagradalsfjall mountain, Krýsuvík, Brennisteinsfjöll mountains and, finally, Hengill mountain.

The last volcanic period began around the year 800 in Brennisteinsfjöll mountains and in the Krýsuvík system, creating the lava fields of Hvammahraun and Hrútafellshraun.

Full article here.
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Update: Lava eruption from long-dormant Icelandic volcano (MARCH 20, 2021) — close to Fagradalsfjall mountain

Earth’s outer shell ballooned during massive growth spurt 3 billion years ago

So the Earth is, or was, a kind of giant balloon. We know seafloor spreading is still ongoing, and can affect global sea levels on historical timescales.
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Ancient fragments of Earth’s crust acted as ‘seeds’ for new crust to grow from, says LiveScience.

Around 3 billion years ago, Earth’s crust ballooned during a massive growth spurt, geoscientists have found.

At that time, just 1.5 billion years after Earth formed, the mantle — the layer of silicate rock between the crust and the outer core that was more active in the past — heated up, causing magma from that layer to ooze into fragments of older crust above it.

Those fragments acted as “seeds” for the growth of modern-day continents.

Doggerland: How did the Atlantis of the North Sea sink?

Hypothetical map of Doggerland [image credit: ancient-origins.net]

This seems semi-topical on the day Britain signs off on its new deal with the EU countries. Going back into history, but not all that far back, the river Thames flowed into the Rhine. North Sea trawlers still find bones of mammoths and other such fossils in their nets today.
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For a long time, scientists believed that a powerful tsunami destroyed Doggerland 8,200 years ago, says DW.com.

Sediment analysis now suggests that the land once connecting Great Britain with the rest of Europe had a later demise.

Around 10,000 years ago, at the end of the last ice age, the sea level in northern Europe was still about 60 meters (197 feet) below what it is today.

The British Isles and the European mainland formed a continuous landmass.

Relatively large rivers crossed this landmass, but in a different way than we know today.

Newly discovered Greenland hot rock mantle plume drives thermal activities in the Arctic

Topographic map of Greenland

We’re told ‘The North Atlantic region is awash with geothermal activity’. Any day now we should be hearing how a few extra molecules of (human-caused) CO2 make the Earth’s innards hotter than they used to be. Or maybe we won’t.
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A team of researchers understands more about the melting of the Greenland ice sheet, says SciTech Daily.

They discovered a flow of hot rocks, known as a mantle plume, rising from the core-mantle boundary beneath central Greenland that melts the ice from below.

Scientists discover volcanoes on Venus are still active

Venus

The presence of sulphur in the atmosphere hinted at this.
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A new study identified 37 recently active volcanic structures on Venus, reports Phys.org.

The study provides some of the best evidence yet that Venus is still a geologically active planet.

A research paper on the work, which was conducted by researchers at the University of Maryland and the Institute of Geophysics at ETH Zurich, Switzerland, was published in the journal Nature Geoscience on July 20, 2020.

“This is the first time we are able to point to specific structures and say ‘Look, this is not an ancient volcano but one that is active today, dormant perhaps, but not dead,'” said Laurent Montési, a professor of geology at UMD and co-author of the research paper. “This study significantly changes the view of Venus from a mostly inactive planet to one whose interior is still churning and can feed many active volcanoes.”

The tsunami that devastated ancient Britain just over 8,000 years ago: new evidence

Position of the Storegga Slide (west of Norway). The yellow numbers give the height of the tsunami wave as tsunamites recently studied by researchers [credit: Lamiot @ Wikipedia] – Mer du Nord = North Sea

The report states: ‘It is thought the tsunami, the largest to hit Northern Europe since the end of the last ice age, happened following a period of global climate change.’
We can only speculate as to the cause(s) of such climate happenings.
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Scientists have found new evidence of a massive tsunami that devastated ancient Britain in the year 6200 BC on the east coast of England, reports the Daily Mail.

The giant tsunami event, known as the Storegga Slide, was caused when an area of seabed the size of Scotland – around 30,000 square miles – under the Norwegian Sea suddenly shifted.

New geological evidence reveals three successive waves tore across an ancient land bridge connecting Britain with the rest of Europe, known as Doggerland, now submerged beneath the North Sea.