Where's Our Ice?
“Arctic ice is rapidly disappearing, and the region may have its completely ice-free summer by 2040 or earlier,” informs IPCC (United Nationsʼ Intergovernmental panel on Climate Change). Our satellites witnessed a heart-breaking sight last thursday, as a chunk of the Petermann Glacier, cooly ﬂoated into the warm waters.
Antarctica is also in no less danger. In 1995, the Larsen A ice-shelf collapsed. In 2002, the Larsen B ice shelf, that had existed for 12,000 years broke apart from Antarctica and ﬂoated away. These vast movements of ice are called ʻcalving events.ʼ Letʼs take a further look at the condition in our poles.
What are ice-shelves?
Just like dams act like a barrier to stop the ﬂow of water, ice-shelves stop glaciers or ice-sheets from ﬂowing into the ocean. They are thick ﬂoating platforms of ice, that are connected to the landmass. Due to gravity, glaciers are pulled towards the ocean, but end up ʻemptyingʼ into the ice-shelf. As this continues, ice-shelves will extend forward for decades to come. Snow accumulation on the top and melting from the bottom also balances the ice on the ice-shelf.
The Role of Climate Change
Researchers believe climate change may play a major role in ice-shelf collapse. Warm waters accelerate the melting of ice-shelves, before it can be replenished by snow or ice from other glaciers. This results in the collapse of ice-shelves. They, then ﬂoat away and latch themselves onto landmasses like Greenland, Canada and Antarctica. These ice- shelves could be a few hundred miles long, or even the size of Texas. Right now, smaller ice-shelves are breaking off, but it is suspected, that larger ice-shelves and glaciers are also in danger in the future.
What are the Effects on Glaciers?
What happens when a dam breaks up? The fast-ﬂowing water engulfs the streams, and swallows neighboring towns. Similarly, glaciers have no ice-shelves to resist the force of gravity. The glaciers end up surging into the waters. Take the example of the Crane glacier, which fed the Larsen B ice-shelf. Ever since, Larsen B collapsed, Crane glacier is cracking up. Many other glaciers are also disintegrating.
From 2001 to 2006, glaciers that once fed the Larsen A and B ice shelves lost about 11.2 billion tons of ice per year. More than 14.5 cubic miles of glacial ice also melted into the oceans.
The Warming World
“You donʼt have to be a rocket scientist to realize that in a warming world, ice is going to melt- so itʼs not surprising that Greenland is responding,” said director of the Bristol Glaciology Centre at the University of Bristol. Even though, the volume of ice lost in the past years havenʼt contributed much to the rise in sea-level, the future is still unpredictable. Thousands of such ʻcalving eventsʼ are happening, and as the temperatures increase, rise in sea-level might become a bigger issue. Some believe, ʻcalving eventsʼ are part of a natural cycle. Whatever be the reason, scientists say that we are in for a tough time, and lack of attention wonʼt stop anything. Things might not be the same as before.