Ice sheets across northern Europe repeatedly met and merged in the North Sea, submerging Britain under frozen water around 1.4 million years earlier than thought.
That’s according to a new study by Manchester and Aberdeen universities that looked at ancient sediment cores around the UK.
Researchers say Britain was repeatedly submerged under a massive ice sheet that generated icebergs more than three times the height of Big Ben.
Beginning around 2.5 millions years ago, this sheet periodically advanced into waters around 820 feet (250 metres) deep where it eventually met and merged with a larger sheet from Scandinavia.
Scientists say the discovery marks a significant breakthrough in our understanding of the extent of past glaciation in North West Europe.
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Britain was repeatedly submerged under a massive ice sheet that extended out into the centre of the North Sea over a million years earlier than previously thought. Periodically, ice sheets from the British Isles and Scandinavia would advance, with the two repeatedly merging in the centre of the North Sea by 1.9 million years ago
A research team led by scientists from the Universities of Aberdeen and Manchester analysed sediment cores and seismic data from deep beneath the North Sea to make the discovery.
The North Sea basin has been continually preserving layer upon layer of sediment over millions of years, which contains evidence for past ice sheets that is not available onshore.
Experts searched these different layers for traces of long-disappeared ice sheets through the evidence in core samples – including their sedimentary structures, minerals and the presence of microfossils.
They discovered that extensive ice sheets repeatedly covered much of the UK and Ireland and, at the same time, an even larger ice sheet covered much of Scandinavia.
The researchers explained that, back then, the North Sea was narrower and deeper than it is today, similar to a large ‘fjord’.
By 1.9 million years ago, the two ice sheets repeatedly merged in the centre of the North Sea, filling the ‘fjord’, as they advanced and retreated in response to climate changes controlled by the Earth’s orbit.
Until now, the scientific consensus said glaciation on this scale first occurred in the North Sea about 1.1 million years ago.
The new research, however, shows it first happened 1.4 million years earlier.
About the findings, published in the journal Science Advances, study leader Dr Brice Rea, of Aberdeen University, said: ‘Through our work with Apache North Sea we obtained sediment core samples from beneath the North Sea at a depth where they are rarely obtained, and combined this with a range of geophysical datasets that were being worked on at the University of Manchester.
‘Coalescence of the British ice sheet and ice from Scandinavia, which we show occurred at about 1.9 million years ago, wasn’t thought to have happened until about 780,000 years ago.
‘Our findings completely change our understanding of how far back in time large ice sheets covered the British Isles and merged with ice from Scandinavia.’
Until now, the scientific consensus has been that glaciation on this scale first occurred in the North Sea about 1.1 million years ago. The new research, however, shows it first happened 1.4 million years earlier. This image shows how the ice sheets appeared around 2.5 million years ago
Earlier this month, a fascinating new interactive map revealed what Britain looked like during the last ice age.
The map reveals where corridors of ice and glacial lakes formed 22,000 years ago, during the peak of the ice age, when a half mile-thick ice sheet covered Britain and Ireland.
Dubbed Britice, the interactive map allowed users to type in their postcode or city to see how their area was affected, and check nearby landforms.
These include enormous glacial lakes, shown in light blue, and areas where rocks and sediments have been deposited by glaciers, shown in brown.
There have been at least five documented major ice ages during the 4.6 billion years since the Earth formed.
The last one took place in the Pleistocene Epoch which began 2.6 million years ago. The ice age peaked 22,000 years ago and lasted until about 11,700 years ago.
The map of the glaciated British landscape, created by scientists at the University of Sheffield, contains more than 170,000 landforms from over 100 years of field investigation.
It is the most complete overview of glacial landforms to date, according to researchers behind the project.
The landforms featured in the map were left behind when a vast ice sheet covered the UK during the last ice age, carving its way through the country and leaving geographical scars that are still present today.
Researchers looked at these marks to track how the ice sheet grew, flowed and eventually disappeared during a this period when average temperatures across Europe dropped 5°C (9°F) below the average today.
This change was enough to stop snow and ice in northern regions from melting during the summer months, covering much of Scotland, Wales, the midlands and northern England in perpetual ice.
Project scientist Dr Jeremy Ely said: ‘The landform information tells us about how the last British-Irish ice sheet behaved.
The online map shows where corridors of ice and glacial lakes formed in the United Kingdom 22,000 years ago, when a kilometre-thick ice sheet covered Britain and Ireland. The coverage of the ice sheet is shown in this image by the lighter colouration. The last ice age peaked about 21,000 years ago and ended about 11,500 years ago
The online map highlights different geographical features using a range of shaded lines and colours. Areas where water has pooled to form enormous glacial lakes are shaded in light blue, while regions of moraine – a mass of rocks and sediment carried and deposited by a glacier – are coloured brown. Pictured is how the North Yorkshire Moors looked 22,000 years ago
Areas shaded in yellow in this snapshot of Northern Ireland show subglacial rib regions – sculpted ridges formed by moving ice. Green areas show regions from which rocks known as erratics were carried long distances by glacial ice flows and meltwater. These areas are dubbed erratic source areas. Green lines show where their erratics were carried
During the last ice age, temperatures dropped so far that snow and ice in northern regions from melting during the summer months, covering much of Scotland, Wales, the midlands and northern England in perpetual ice. The new map reveals that the furthest southern region affected by the geological event was Cambridge, which was covered by a huge glacial lake (blue)
‘We can see how it dammed rivers, creating large glacial lakes which covered Manchester, Doncaster and Peterborough.
‘Corridors of fast flowing ice, known as ice streams, flowed toward the east over Edinburgh and toward the west over Glasgow.
‘Ice also covered the entirety of Ireland, flowing through the Irish Sea, where it coalesced with Welsh ice, causing it to flow southward toward the Isles of Scilly.’
The online map highlights different geographical features using a range of shaded lines and colours.
Pink lines on the map show glacially streamlined bedrock, which have been eroded by ice and water flow. Grey lines show a cirque, a bowl-shaped depression on the side of or near mountains carvedout by ice. Crag and tails are revealed by yellow lines. These are a tadpole-shaped landforms developed by glacial erosion of rocks on unequal resistance
22,000 years ago ice covered the entirety of Ireland, flowing through the Irish Sea, where it coalesced with Welsh ice. This image shows southern regions of Ireland, with erratic sources and their flows of rocks in greem while subglacial ridges are depicted in yellow. Brown shows regions of moraine
Routes where huge lumps of rocks were carried, typically by shifting glacial ice, are called erratic pathways and are shown as dark green lines on the map (left). Red lines show eskers, which are long ridges of gravel deposited by meltwater, while channels burrowed by meltwater from the ice sheet are delineated as light blue lines
The landforms featured in the map were left behind when a vast ice sheet covered the UK during the last ice age, carving its way through the country and leaving geographical scars that are still present today. This image shows the sheer extent of ice coverage over northern England and southern areas of Scotland
WHAT DID BRITAIN LOOK LIKE DURING THE LAST ICE AGE?
The last Glacial Maximum was around 22,000 years ago when much of Europe was covered in ice.
During the ice age, which ended about 11,500 years ago, ice covered about 30 per cent of the land in the world.
In Britain, glacial ice and waterflows spread as far south as the Bristol Channel.
Average temperatures were 5°C (8°F) colder than they are today, allowing a one-kilometre-thick sheet of ice to cover much of the country.
The temperature remained below 0°C all year round in northern regions, particularly Scotland, allowing the sheet to remain on the land all year.
Ice connected Britain with Scandinavia, allowing a host of large wildlife to roam free between the UK and mainland Europe.
During this period Britain would have seen the likes of woolly mammoths, giant deer and wolves roaming its icy planes.
Large glacial lakes covered Manchester, Doncaster, Newcastle and Peterborough and much of the country was uninhabitable for humans.
Corridors of fast flowing ice, known as ice streams, flowed toward the east over Edinburgh and toward the west of Glasgow.
All of Ireland was covered in ice, which was flowing through the Irish sea where it met Welsh ice and then flowed south toward the Isles of Scilly.
Much of Scotland, Wales, the midlands and northern England was covered in perpetual ice.
Cambridge, which was covered by a huge glacial lake, was the most southern region to be heavily affected by the icy climate.
Over time the ice and its hefty waterflows carved out the land of Britain, forming geological scars that can still be seen today.
These include glacial ridges sculpted by moving ice and winding flows of rock that travelled for miles across the country.
Areas where water has pooled to form enormous glacial lakes are shaded in light blue, while regions of moraine – a mass of rocks and sediment carried and deposited by a glacier – are coloured brown.
Routes through which huge lumps of rocks were carried, typically by shifting glacial ice, are called erratic pathways and are shown as dark green lines on the map.
Red lines show eskers, which are long ridges of gravel deposited by meltwater, while channels burrowed by meltwater from the ice sheet are delineated as light blue lines.
The map shows that a glacial lake (light blue) formed around the north-west corner of East Anglia around the rectangular bay and estuary known as the Wash. This was kept from flowing into the North Sea by glacial lake dams (dark blue)
Northern Scotland featured an array of erratic sources (green regions) that pumped rock along winding rivers of glacial meltwater (green lines)
The Britice project, funded by the Natural Environment Research Council, has seen researchers work for six years to model the build-up and retreat of the last British-Irish ice sheet. This image shows what Wales would have looked like
The Britice project, funded by the Natural Environment Research Council, has seen researchers work for six years to model the build-up and retreat of the last British-Irish ice sheet.
The programme has involved more than 70 scientists from around the world who have visited 28 different islands and collected more than 15 tonnes of samples from 914 sites.
As well as the online map, a physical accompanying map poster has been distributed to all secondary schools in the UK to assist pupils studying glacial landscapes and processes as part of their GCSE and A Level studies.
HOW DID STONE AGE HUNTERS DEAL WITH ICY TEMPERATURES IN BRITAIN 11,000 YEARS AGO?
Stone Age hunter gatherers in Britain 11,000 years ago were far more resilient to extreme cold weather than scientists previously thought, according to a recent study.
Experts found that a dramatic drop in temperatures, severe enough to halt woodland development, had no substantial impact on human activity at Star Carr.
Prehistoric dwellers at the middle Stone Age archaeological site, which dates to around 9,000 BC, persevered through a cold snap that lasted more than 100 years.
The study sheds new light on debate surrounding the sensitivity of hunter-gatherer societies to environmental change, suggesting they were hardier than assumed.
Researchers at Royal Holloway, University of London, and the University of York examined items found at the site, around 23 miles (37 km) north-east of York.
The rich archaeological record gave scientists the rare opportunity to compare the climate record, discovered through analysis of ancient peat taken from core samples, with evidence of human activity.
This included worked wood, animal bones, antler headdresses and flint blades, found buried in layers of mud.
These artefacts are evidence of the continued productivity and endurance of people at Star Carr throughout the years of extreme cooling, which saw average temperatures drop by more than 3°C (5.4°F) in the space of a decade.
They found pioneering early modern humans who lived at site at the end of the last ice age carried on with life as usual, despite plummeting temperatures.
Speaking to MailOnline, researcher Nicky Milner said: ‘This was a time before farming, before pottery, before metal. People were living by hunting and gathering for their food
‘However, they were still highly skilled and could build houses, had axes to chop down trees and could make boats.
‘Despite the climate change, they seem to have carried on living much the same as they had done previously – hunting the same animals and living by the side of the lake, which presumably provided them with various resources.’
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