Thursday, December 3, 2015

See how deepest ocean currents move

Chief Investigator, Dr Andy Hogg, from the ANU hub of ARC Centre of Excellence for Climate System Science worked with the National Computational Infrastructure’s VizLab team, using a high-resolution ocean model, to produce the animation.
The visualization has revealed underwater ocean storms generated by eddies, waterfalls of cold dense water that plummet two kilometres off the Antarctic Continental Shelf into the abyss and underwater waves hundreds of metres high.

From Discovery by Patrick J. Kiger

Deep in the Southern Ocean lies the densest and coldest water on the planet. But that doesn’t mean that it isn’t moving.
On the contrary, a vividly detailed animation of deep ocean currents, created by Australian scientists with the help of their country’s most powerful supercomputer, reveals a deep-sea world that’s full of dynamic activity.
It shows underwater ocean storms generated by eddies, waterfalls of cold dense water that plummet off the Antarctic Continental Shelf into the abyss and underwater waves more than a mile high.
NEWS: Map of Ocean Currents Created from Space

"Scientists who have seen the visualization have been astonished at the level of detail,” Andy Hogg, an associate professor and ARC Future Fellow at Australian National University, said in a release.
Hogg is also a member of the ARC Centre of Excellence for Climate System Science.
The animation required so much data that it took seven hours to process a single second of the finished product.

But the animation is more than just a bunch of pretty pictures.
“Being able to actually see how the bottom water moves in three dimensions rather than just looking at numerical, two-dimensional outputs has already opened new areas for scientific research,” Hogg said.
By peeling away the surface layer of water, the animation shows how the cold, dense water produced off the Antarctic coastline spreads out into the rest of the world’s ocean basins.
The water’s extreme density and coldness drive many important currents in the ocean basins connected to the Southern Ocean.

The water movement also helps the planet to cope with global warming driven by human burning of fossil fuels.
As water near the surface is drawn deep, it takes with it heat and carbon that otherwise would have been returned to the atmosphere.
 ”The inhospitable climate of Antarctica and the lack of sustained observations of the ocean in this region over a significant period of time adds to the importance of using ocean models to create visualizations like these,” Hogg explained.
From Hogg’s web page, here’s a more detailed explanation of Southern Ocean circulation.

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Wednesday, December 2, 2015

NZ Linz update in the GeoGarage platform

WWII wrecks and Darwin's ice age history unveiled by start-of-the-art technology

(ABC News)

From ABC by James Dunlevie

On first glance, Darwin Harbour appears much like any other Australian port, but a new geographic survey has documented ancient geography and ghostly shipwrecks in unprecedented detail.

 Darwin Harbour with the GeoGarage platform (AHS nautical chart)

Navy and merchant shipping sunk by Japanese air raids in 1942, as well as the wreck of a ship lost during Cyclone Tracy in 1974, have been captured in the new marine survey of Darwin Harbour by Geoscience Australia, the first results of which have been publicly released.
Beginning in May this year, the research ship Solander operated 24 hours a day over a month mapping Darwin's northern beaches and northern coastline of Cox Peninsula, using "multi-beam echo-sounder technology".

 The Booya, which sunk in high seas caused by Cyclone Tracy in 1974.

Geoscience Australia said the collaborative four-year project, with the Australian Institute of Marine Science and the NT Government, brought together "over 50 years of experience in sea-floor mapping and has enhanced efforts for better estuary and coastal management in the area".
The results of the survey, which Geoscience said revealed "relicts of Australia's ancient geography in the form of sub-marine sand dunes, ripples and sand waves", also generated new bathymetric imagery of the Booya, a ship which took shelter in the harbour as Cyclone Tracy approached but was sunk, with five lives lost.
Also mapped was the World War II American transport ship USAT Meigs, which was torpedoed and bombed during the Japanese surprise attacks of February 1942.

 An bathymetric image showing the wreck of the Booya on its side,
with the different depths indicated by colour changes.

"These images are a great contribution to our continuous efforts to better understand our marine archaeology, and to manage these historic shipwrecks in Darwin Harbour," said David Steinberg, senior heritage officer with the NT Government.
Geoscience said the mapping helped understand the area's geography as far back as "the last ice age, some 20,000 years ago", to a time when a land bridge existed between northern Australian and New Guinea.

 Coloured bathymetric image of underwater ripple formations and sandwaves
on the Darwin Harbour sea floor

"This crucial research significantly enhances our efforts for better estuary and coastal management of this area, while creating the best-mapped tropical macro-tidal system in the world," Neil Smit, a scientist on the project, said.
"It's also an exciting test case for scientists who hope to better understand complex environmental systems like Darwin Harbour."
The project was funded by Inpex, operators of the Ichthys LNG project.

(Supplied: Australian War Memorial (P05303.022))

A murky world of graves and twisted metal

Recreational divers, if they are not put off by the low visibility of Darwin's murky waters, reptilian predators or perilous jellyfish, are asked to take a "look but don't touch" approach to the many heritage-listed ship and aircraft wrecks scattered on the harbour floor.
Official records list 25 vessels, including fishing trawlers, ferries, yachts and naval craft, as wrecked or missing after Cyclone Tracy in 1974, with 16 people dying at sea.
The Booya, a 35-metre three-masted schooner, was anchored on Christmas Eve when Tracy hit Darwin.
The wreck was discovered in 2003 at a depth of about 20 metres - with authorities in recent times pleading for respect to be shown to the exclusion zone around the site, as the Booya deck "displays the efforts of the crew to save the ship".
In February 1942, the US Navy destroyer USS Peary, US transport ships Meigs and Mauna Loa, Royal Navy tanker British Motorist, cargo ship Neptuna and other shipping were caught by surprise in Darwin Harbour when over 200 Japanese planes attacked in two raids.
The Neptuna, laden with a cargo of depth-charges and explosives, was hit and caught fire, with many killed as they prepared to abandon ship by an explosion.

 A bathymetric image of what remains of the 131-metre long WWII US Navy ship Meigs,
which lies on the floor of Darwin Harbour after being sunk by the Japanese in 1942.

The Peary was reportedly hit by at least five Japanese bombs as it attempted to make for the open sea, with a hit on its ammunition store the final blow.
The Mauna Loa is reported to have sunk after being hit by two bombs that went through an open cargo hatch.
Now sitting in about 18 metres of water, the twisted deck of the Mauna Loa is littered with ammunition, motorcycles and gun carriers.
Official records list the death toll of the two raids numbering "at least 243 people", with between 300 and 400 wounded.
Over 60 subsequent attacks on Darwin would take place during the conflict.
In a final irony, the salvage rights to the scrap metal of many shipwrecks were sold to a Japanese company in 1959.

(Supplied: Australian War Memorial 044603 )

Tuesday, December 1, 2015

US NOAA update in the GeoGarage platform

Turkey blockading Russia from Dardanelles

Turkey has begun a defacto blockade of Russian naval vessels, preventing transit through the Dardanelles and the Strait of Bosporus, between the Black Sea and Mediterranean.
According to the AIS tracking system for the movement of maritime vessels, only Turkish vessels are moving along the Bosphorus, and in the Dardanelles there is no movement of any shipping at all.
At the same time, both from the Black Sea, and from the Mediterranean Sea, there is a small cluster of ships under the Russian flag, just sitting and waiting. 

- courtesy of MarineTraffic -

From The Daily Caller

Turkey slammed the door on Russian sea travel Sunday, effectively shutting off Moscow’s access to the Black Sea and raising serious concerns among experts about escalating tensions in the region.
The recent blockade is preventing Russian naval vessels from traveling in the Black Sea to Syria.
The Russian Black Sea fleet has been a key component to Russian operations in the war-torn country, primarily operating out of the Syrian port of Tartus.
Without access to the Turkish Straits, Russian attempts to increase force projection in Syria or resupply the units in the country will be extremely limited.
“This better be a joke — because if not, WW3 is about to start,” quipped John Schindler, former NSA operative and national security columnist at the Observer.

'Yauza', a logistics ship of the Russian Navy passes through the Dardanelles
in front of a Turkish submarine on Nov. 30 
(see video)

Schindler’s concern is certainly warranted.
The conflict between Russia and Turkey adds fuel to the raging fire that is Syria.
As a NATO member, Turkey is party to Article 5 of the NATO convention which considers an attack on any of the NATO allies an attack on them all, including the United States.
NATO has shown support for Turkey throughout the incident and the issue will certainly be brought up as Turkish President Ahmet Davutoglu visits NATO General Secretary Jens Stoltenberg today.

The blockade is the most recent counter in the standoff between the Turkish and Russian governments that was sparked by the downing of a Russian Su-24 bomber by Turkish forces last week.
In response, Russian President Vladimir Putin announced Saturday that Russia would begin sanctions against certain Turkish exports as well as a halt to charter flights between the two countries. Additionally, Russia armed its fighter aircraft with air-to-air missiles for the first time Monday, giving them an offensive capability against any future aggression by Turkish aircraft.
“The egos of Putin and Erdogan may spin any future incident beyond control,” Boris Zilberman, a Russia expert at the Foundation for Defense of Democracies, a D.C.-based think tank, told Business Insider.

Dardanelles Straight with the GeoGarage platform (NGA chart)
It is a 1936 agreement that gives Turkey control over the Bosporus Straits and the Dardanellesand regulates the transit of naval warships.
The Convention gives Turkey full control over the Straits and guarantees the free passage of civilian vessels in peacetime.
It restricts the passage of naval ships not belonging to Black Sea states.
The terms of the convention have been the source of controversy over the years, most notably concerning the Soviet Union's military access to the Mediterranean Sea

As the only direct Russian access point to the Mediterranean, the effects of the Turkish blockade pose both economic and military concerns for Russia.
Turkey is Russia’s second largest trade partner, while the Turkish Straits (the Bosporus and Dardanelles) are a primary shipping lane for Russian oil exports.
Any potential deployment of Russian ground forces to Syria would be significantly hampered by the blockade, along with the resupply of the current Russian forces based in Syria.
The blockade is not the first instance of conflict between Russia and Turkey over access to the Straits. In the early years after World War II, Turkey was pressured by the then Soviet Union to allow unfettered Soviet access to the Straits.
Tensions between the two countries eventually led to Turkey joining NATO in 1952, thus giving the country protection from the United States.
The access dispute has never been formally settled.

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