100 Places To Remember: Ross Ice Shelf, Antarctica
Geschreven op 30-4-2010 - Erik van Erne. Geplaatst in Natuur
Hush, be quiet! The mystic Barrier! The Ross Ice Shelf in the Antarctic is Earths largest ice shelf and forms part of its biggest ice mass. It contains a massive 70% of the fresh water on the planet. Named after James Clark Ross, the British naval officer and explorer who first set eyes on it in 1841, it is associated with dangerous adventures, heroic discoveries – and an uncertain future.
In 1911, when it was still known as the Ice Barrier, the explorers Robert F Scott and Roald Amundsen set off on their legendary race to the South Pole from opposite edges of the shelf. In his book South Pole, Amundsen records his immediate feelings on arriving at its huge face for the first time: Hush, be quiet! The mystic Barrier!
The Ross Ice Shelf is linked to the Antarctica but most of it floats on the sea. At 487,000 square kilometres it is almost as big as France. The sea-facing side is almost 600 km long, its vertical face rising to heights of 15-50 metres. Only 10% of the shelf is above water and visible; at its thickest, it plunges several hundred metres below the water line.
In the last 50 years, the average temperature on the west coast of the Antarctic has risen by almost 3ºC, ten times the average increase for the planet as a whole.
The temperature in and above the sea around the Antarctic is projected to rise again over the next 100 years. This could lead to the Ross Ice Shelf collapsing and breaking away from the continent, which would raise sea levels quite dramatically all over the world and cause further melting of the ice on the Antarctic continent.
Erik van Erne zegt:
22 februari 2018 om 20:01 | Permalink
Deep Bore Into Antarctica Finds Freezing Ice, Not Melting as Expected by National Geographic
At the Ross Ice Shelf in Antarctica, scientists used a hot-water drill hose to create a hole through the thick ice until they reached the perpetually dark water. What they found surprised them.
This is the Ross Ice Shelf – the biggest floating ice shelf in Antarctica. Such shelves are important because they hold back a vast amount of ice. If all such West Antarctic shelves were to collapse and spill the ice into the ocean then global sea level would rise by 10 feet. Beneath the Ross Ice Shelf is one of the least explored bits of ocean on Earth. New Zealand scientists used a hot-water drill hose to create a hole through the thick ice until they reached the perpetually dark water. They hoped to study the health and history of the shelf. Their findings surprised them. They found that the ice in the hole itself and along the base of the shelf was crystalizing and freezing rather than melting. Measurements will be taken for the next few years, to see how the Ross Ice Shelf is changing over time.