October 4, 2019 (updated October 5, 2019)
Published by Gayathry
Researchers observed a “loose tooth” of ice dangle from the edge of the Antarctic ice sheet for 20 years, waiting to be detached. However, the wrong portion was observed as a nearby sheet of ice along with the same rift system, larger than its wobbling neighbor has broken off the Amery ice board according to the Australian Antarctic Division.
The massive iceberg known as D28 covering 1,636 square kilometers (632 square miles) with a depth of nearly 210 meters deep (689 feet) is approximately the size of urban Sydney. It is the largest iceberg weighing about 315 billion tonnes formed by the Amery ice shelf in more than fifty years.
Helen Fricker, a researcher from the Scripps Institution of Oceanography said that it is the molar compared to a baby tooth. Fricker says that the disintegration of the ice shelf from its edges is a natural phenomenon known as calving. It is to make space for new streams of ice and snow. Each individual ice sheet undergoes a different rate of calving which varies across seasons and takes more than decades to complete since it is an important way to balance masses of ice sheets around the world.
Researchers were unable to predict the location and timeline of calving in this case as all these parameters make it difficult to anticipate from beforehand. Fricker said that they anticipated a huge iceberg would break off between 2010 and 2015 when they first observed a split at the front of the ice board in the early 2000s. The event ultimately occurred after all these years however not at the location predicted by the researchers.
Amery ice shelf produced an iceberg like this covering an area of 9000 square kilometers in 1963. This ice shelf is normally expected to undergo one major calving event every six or seven decades, and so far two have been observed in the cycle. Hence this is not related to the global change of climate, although this is not the situation always.
For example, instead of every six years, the calving rate of Pine Glacier situated in Western Antarctica has accelerated, spreading deeper and shedding huge icebergs in 2013, 2015, 2017, and 2018 which is clearly not as per its normal timeline.
Sue Cook from the Institute of Marine and Antarctic Studies (IMAS) said that she expects the calving rate to increase because of climate change. She explained that icebergs will start becoming thinner as waters around Antarctica warm-up making them more vulnerable to breaking up.
August 13, 2019
Published by Kalpit Veerwal
Although it might sound crazy, architects have proposed the design for a submarine which produces icebergs in an attempt to restore the ice caps of Arctic. The team aims to form new glaciers in this technique by bringing together a swift of these vessels that will eventually help to balance arctic eco-system.
Recently, an international contest conducted by the Association of Siamese Architects awarded a second prize to the revolutionary proposal. It is yet to be checked if the idea can be practically implemented.
The Arctic Ocean has lost 95 percent of its oldest ice over the last three decades. This intense melting in association with global warming has created an ecological imbalance in the Arctic. It has damaged the natural food chain of the Arctic forcing fish, seals, wolves, polar bears into ever lesser regions. The team hopes to help the Arctic through their prototype inspired by the similar lines of re-forestation resulting in ‘re-iceberg-isation’ in the Arctic.
The submarine would function by re-freezing Arctic marine water into hexagon-shaped icebergs, each about 2,027 cubic meters (535,477 gallons) eventually gathering together to form new ice floes. The floating submarine would extract some of the salt from the collected marine water in a tank using a method of reverse osmosis making freezing easier. The left-over seawater would be frozen into a hexagon-shape iceberg and released back into the ocean after a month by the use of air turbines.
Group member and Indonesian designer Faris Rajak Kotahatuhaha mentioned the primary objective is to recover the arctic ecosystem which impacts the global climate. It does not control the emissions but it could help ensure affluent habitats and hunting stage. The size of the design would have to be enormous in order to actually avoid further sea-level rise as claimed in a video for the new prototype by the architects.
The actual risk of sea-level rise is not the melting icebergs as they are already floating in the ocean but the melting land ice which flows into the ocean. The newly created icebergs would have to somehow end up on land to make an impact. The newly formed icebergs protect ocean water by reflecting Sun’s energy and blocking absorption but to make a big influence, they need to cover a large area of the arctic ocean.
Atmospheric scientist Michael Mann commented that the model is like attempting to save sandcastle from the waves using a paper cup. There are various questions apart from sea-level about the powering of the submarine and whether adequate wind energy can be collected to freeze their huge swallows of water. It is also to be seen if these vessels are powered by renewable energy. Even now our best solution to control the rise of sea levels is to reduce the emissions.