Groundbreaking discovery off the UK coast reveals fingerprints of city-sized icebergs that once roved Britain and Ireland’s coasts, providing a unique window into the past behavior of the British-Irish ice sheet.
Researchers have made a groundbreaking discovery off the UK coast, uncovering fingerprints of city-sized icebergs that once roved the coasts of Britain and Ireland about 18,000 years ago. This finding provides valuable insights into the past behavior of the British-Irish ice sheet and its potential impact on Antarctica today.
Glacial remnants are fragments of glaciers that remain after the main glacier has retreated.
These remnants can be found in high-latitude and high-altitude regions, where the climate is cold enough to sustain ice masses.
They often take the form of small glaciers, 'ice caps' , or 'ice fields' .
Glacial remnants provide valuable information about past climates and can serve as indicators of future climate change.
In some cases, they also support unique ecosystems that are adapted to the harsh glacial environment.
The Search for Evidence
Scientists employed detailed 3D seismic data, collected by oil and gas companies or wind turbine projects doing ocean surveys, to search for signs of giant icebergs. By analyzing these records, they found deep, comb-like grooves interpreted as the keels of large icebergs that broke off the British-Irish ice sheet.
The Significance of Ice Shelves
Ice shelves are floating platforms of ice where glaciers extend out into the ocean. These structures play a crucial role in holding back the flow of continental ice into the ocean. The discovery of city-sized icebergs suggests that the UK had ice shelves, as these massive bergs could only be produced by such platforms.
Ice shelves are thick, floating extensions of glaciers that connect to the surrounding land.
They form when a glacier flows over the ocean and its front becomes grounded on the seafloor.
Ice shelves can be up to 1 km thick and cover vast areas.
They play a crucial role in regulating sea levels by preventing glaciers from flowing freely into the ocean.
However, 'ice shelves are fragile and vulnerable to climate change' , with many collapsing due to warming temperatures.
Estimating the Size of the Icebergs
The scientists estimated that these icebergs could be five to tens of kilometres wide and 50-180m thick, covering an area roughly equivalent to medium-sized UK cities like ‘Norwich’ or ‘Cambridge’. This finding provides a unique window into the past behavior of the British-Irish ice sheet.
Implications for Antarctica
The loss of ice shelves is a critical factor in understanding how climate change affects Antarctica today. The disintegration of Britain‘s former ice shelves coincided with the time when glaciers behind began to retreat faster and faster. Resolving the question of whether the disintegration of ice shelves triggered the runaway retreat of ice is crucial for predicting the impacts of losing today’s Antarctic ice shelves.
A New Perspective
The discovery of city-sized icebergs off the UK coast offers a fascinating glimpse into the past behavior of the British-Irish ice sheet. By analyzing these records, scientists can better understand how climate change affects Antarctica and shed light on the complex dynamics at play in the Earth’s cryosphere.
Glaciers have been a dominant feature on Earth's surface for millions of years.
They form when snow accumulates and compresses, transforming into ice over time.
The weight of the ice causes it to flow under its own gravity, carving out valleys and creating unique landscapes.
Glacial history reveals that they have expanded and retreated multiple times due to climate fluctuations.
For example, during the last 'ice age' , glaciers covered a significant portion of North America and Europe.
As temperatures rose, these glaciers began to melt, leading to their current reduced size.
