ANTARCTICA is losing ice at a rapid rate, according to new satellite information.
Glaciers are now sliding into the sea because of the warming Southern Ocean as ice vanishes five times faster than it did in the 1990s.
The West Antarctic ice sheet used to be stable a few decades ago but new evidence shows that up to a quarter of it is now thinning.
In the worst hit locations, more than 100 metres of ice thickness has been lost.
Completely losing the West Antarctic ice sheet would result in global sea levels rising by about five metres.
This amount of sea level rise would drown coastal cities around the world.
Scientists think that sea levels are now rising at the extreme end of what was predicted to happen gradually just a few years ago and current losses of ice are said to be doubling every decade.
This research has been published in the journal of Geophysical Research Letters.
It describes how scientists used satellites images to compare the sizes of ice sheets from 1992 to 2017 with weather information.
Professor Andy Shepherd, who led the study, said: “From a standing start in the 1990s, thinning has spread inland progressively over the past 25 years – that is rapid in glaciological terms.
“The speed of drawing down ice from an ice sheet used to be spoken of in geological timescales, but that has now been replaced by people’s lifetimes.”
Shepherd also stressed that some glaciers, such as the Pine Island and Thwaites glacier basins, are past the halfway point of melting.
This new work should help researchers to more accurately pinpoint where sea levels will rise so appropriate preparations can be made to try and save affected areas.
The underside of glaciers are thought to be melting because the sea is too hot and not even snowfall can counteract the damage.
Shepherd added: “In parts of Antarctica, the ice sheet has thinned by extraordinary amounts.”
He now thinks West Antarctica melting has caused 5mm of sea level rise since 1992.
He concluded: “Before we had useful satellite measurements from space, most glaciologists thought the polar ice sheets were pretty isolated from climate change and didn’t change rapidly at all.
“Now we know that is not true.”
Rising sea levels – what’s the problem?
Here’s what you need to know…
- The global sea level has been gradually rising over the past century
- Sea levels rise due to two main reasons
- The first is thermal expansion – as water gets warmer, it expands
- The second is melting ice on land, adding fresh water into seas
- This has a cyclical effect, because melting ice also warms up the planet (and oceans), causing more even ice to melt and boosting thermal expansion
- It’s currently rising at a rate of around 0.3cm per year
- The sea is huge, so that might sound harmless
- But rising sea levels can have a devastating effect over time
- Low-lying coastal areas can disappear completely, even putting areas of the UK at risk
- It can also mean sea storms and tsunamis can have a more devastating effect, reaching further in-land than they would have previously
- There’s also an increased risk of flooding
In other news, a study found that the world’s biggest ice sheet is melting 10 times faster than expected.
Another recent permafrost study found that diseases laying dormant in ancient ice could soon be unleashed due to climate change.
And, scientists have warned that two thirds of ice in the Alps will melt by 2100.
What do you think about the rapid ice melting? Let us know in the comments…
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