Tag Archives: Climate change

THE NORTHWEST PASSAGE

21 Feb

For centuries explorers and ships have been lost in an attempt to find a path through this icy maze, a path that would allow faster transit between the Atlantic and Pacific oceans (said to be 40% quicker than through the Panama Canal). Amundsen realized that sea nearest to the mainland remained passable for longer for navigation. He was the first to sail from the Atlantic to the Pacific but the journey took years (1903-1906). His route was through shallow waters.
In 1957, three American Coast Guard Cutters, Storis, Bramble and Spar became the first to navigate a Deep Water Passage through the Northwest Canadian Archipelago but the time and costs involved were not economic in commercial terms. Now as an example of the benefits of climate change, the recent opening up of the Northwest Passage is one of the most remarkable. Previously any cargo vessel needed an escort from Canadian icebreakers.
The ice melt reached a point last year that allowed a strengthened cargo vessel to navigate through the passage without this escort. 23,000 tons of nickel were transported from a Canadian mine to China via the deep-water passage, saving time and costs – a remarkable first!
The Passage is within the Arctic Circle. Inevitably, as with the Antarctic, sovereignty questions arise. The United States, Canada, Russia and Denmark (Greenland), all have significant interests within the region. In addition, as mentioned in the Geographical (February, 2015), the Inuit population hunt and travel over the area. Canadian Rangers now mount permanent sovereignty patrols. Some Russians (inevitably) have suggested that the Rangers role is a militarization issue; the Rangers operate snow machines that keep the passage open. Let’s hope that their role will be accepted as a service to the worldwide community.

New(ish) Antarctic news

31 Jul

Two newish pieces of news on climate change

NEW HUGE ICEBERG

Pine Island Glacier, which is on the west coast of Antarctica, is the most rapidly shrinking glacier in the planet.It is also the longest and fastest flowing glacier in Antarctica and has now produced a huge iceberg; eight times the size of Manhattan Island!! The original crack was seen in October 2011.

Apparently big tabular bergs come off from the end of the ice shelf every 6-10 years so this development is not necessarily related to climate change. But scientists have seen thinning and increased flow in Pine Island Glacier recently, this, they think may be due to warmer water getting under and melting the ice shelf. So there may be a connection.

GLASS SPONGES

I had never heard of glass sponges.  They are invertebrates, their elegant lattices are made of silica.

Their home was in deep water beneath the permanent ice shelves. Until previously they were thought to take years (centuries) to spread.

Unexpectedly, under newly thawed ice sheets, they have produced an invertebrate invasion on the sea floor! It is now known that the ghostly sponges are capable of unexpectedly rapid progression, sprouting in a few years in the Larsen Ice Shelf region (the northwest part of the Weddell Sea). Comparative studies between 2007 and recently found a large increase in the numbers of glass sponges ie they are capable of rapid reproduction, growth spurt and colonisation of large areas of seafloor in short times.

Since they have evolved over 550 million years this is a remarkable example of old and new developments.

Is this Global Warming produced by human activity?