Saturday, December 15, 2018

Canada CHS layer update in the GeoGarage platform

45 nautical charts have been updated & 1 new inset added
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Fake maps, very dishonest


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Friday, December 14, 2018

Why deep oceans gave life to the first big, complex organisms

Fossil photo from the Ediacara Biota.
(Photo by James Gehling)

From Phys

In the beginning, life was small.
For billions of years, all life on Earth was microscopic, consisting mostly of single cells.
Then suddenly, about 570 million years ago, complex organisms including animals with soft, sponge-like bodies up to a meter long sprang to life.
And for 15 million years, life at this size and complexity existed only in deep water.

Scientists have long questioned why these organisms appeared when and where they did: in the deep ocean, where light and food are scarce, in a time when oxygen in Earth's atmosphere was in particularly short supply.
A new study from Stanford University, published Dec.12 in the peer-reviewed Proceedings of the Royal Society B, suggests that the more stable temperatures of the ocean's depths allowed the burgeoning life forms to make the best use of limited oxygen supplies.

Graphic showing origins of different Ediacarans
Thermal stability in the deep ocean fostered complex life
All of this matters in part because understanding the origins of these marine creatures from the Ediacaran period is about uncovering missing links in the evolution of life, and even our own species.
"You can't have intelligent life without complex life," explained Tom Boag, lead author on the paper and a doctoral candidate in geological sciences at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth).

The new research comes as part of a small but growing effort to apply knowledge of animal physiology to understand the fossil record in the context of a changing environment.
The information could shed light on the kinds of organisms that will be able to survive in different environments in the future.

"Bringing in this data from physiology, treating the organisms as living, breathing things and trying to explain how they can make it through a day or a reproductive cycle is not a way that most paleontologists and geochemists have generally approached these questions," said Erik Sperling, senior author on the paper and an assistant professor of geological sciences.

Playful illustration shows the appearance of life on Earth as well as the events that preceded it (and were necessary for it).
Complex life develops in the ocean at first, but soon it will try to see how it is on land.
Sea animals are coming out on land in search of food and new experiences.

Goldilocks and temperature change

Previously, scientists had theorized that animals have an optimum temperature at which they can thrive with the least amount of oxygen.
According to the theory, oxygen requirements are higher at temperatures either colder or warmer than a happy medium.
To test that theory in an animal reminiscent of those flourishing in the Ediacaran ocean depths, Boag measured the oxygen needs of sea anemones, whose gelatinous bodies and ability to breathe through the skin closely mimic the biology of fossils collected from the Ediacaran oceans.

"We assumed that their ability to tolerate low oxygen would get worse as the temperatures increased.
That had been observed in more complex animals like fish and lobsters and crabs," Boag said.
The scientists weren't sure whether colder temperatures would also strain the animals' tolerance.
But indeed, the anemones needed more oxygen when temperatures in an experimental tank veered outside their comfort zone.

Together, these factors made Boag and his colleagues suspect that, like the anemones, Ediacaran life would also require stable temperatures to make the most efficient use of the ocean's limited oxygen supplies.

 Factors governing oxygen supply to animals. 
(a) Average annual partial pressure of O2 (pO2) in the global ocean at surface. 
(b) Average annual solubility of O2 (αO2) in the global ocean at surface. Values increase with latitude owing to the thermal effects on Henry's solubility coefficient. 
(c) Average annual diffusivity of O2(DO2) in the global ocean at surface. 
(d) Average annual bioavailability of O2 in the global ocean at surface, expressed using the oxygen supply index (OSI)
Despite the increased solubility of O2 in cold water, the kinematic viscosity also increases substantially, reducing the diffusivity of O2 at a rate greater than the offsetting effect on solubility.
As a result, the supply of O2 to respiratory surfaces actually decreases approximately linearly as water becomes colder.

 Refuge at depth

It would have been harder for Ediacaran animals to use the little oxygen present in cold, deep ocean waters than in warmer shallows because the gas diffuses into tissues more slowly in colder seawater.
Animals in the cold have to expend a larger portion of their energy just to move oxygenated seawater through their bodies.

But what it lacked in useable oxygen, the deep Ediacaran ocean made up for with stability.
In the shallows, the passing of the sun and seasons can deliver wild swings in temperature—as much as 10 degrees Celsius (50 degrees F.) in the modern ocean, compared to seasonal variations of less than 1 degree Celsius at depths below one kilometer (.62 mile).
"Temperatures change much more rapidly on a daily and annual basis in shallow water," Sperling explained.

Impact of seasonal temperature variation on aerobic respiration in low pO2 conditions
In a world with low oxygen levels, animals unable to regulate their own body temperature couldn't have withstood an environment that so regularly swung outside their Goldilocks temperature.

The Stanford team, in collaboration with colleagues at Yale University, propose that the need for a haven from such change may have determined where larger animals could evolve.
"The only place where temperatures were consistent was in the deep ocean," Sperling said.
In a world of limited oxygen, the newly evolving life needed to be as efficient as possible and that could only be achieved in the relatively stable depths.
"That's why animals appeared there," he said.

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Thursday, December 13, 2018

Mechanics of Nazaré

Nazare in full glory.
Photo: Andre Bothelo

From Surfline

How one break in Portugal creates the world's largest waves

A wave that produces the 80-foot Guinness world record for largest wave ever ridden needs no introduction.
Even to the non-surfing community, little is needed when mainstream media regularly runs photos and videos of every XXL swell that hits the small Portuguese fishing town.
Hell, CNN’s Anderson Cooper even rode through the rocks on the back of a ski — piloted by none other than previous world record holder (also caught at Nazaré), Garrett McNamara.

Above: Under the right conditions, XL Nazare looks almost inviting.
Photo: Jeremiah Klein

Nazaré is well known for good reason.
It regularly produces the largest rideable waves on planet Earth.
And thanks to the ultimate deepwater canyon set up, Nazaré’s surf size potential is only bound by the size and direction of the swell it receives.

Swell Source
  • Strongest swells of year from October through April when intense mid-latitude frontal lows track eastward across the North Atlantic, interacting with adjacent high pressure.
  • Typical storm track moves towards Europe helping maximize swell potential.
  • Strongest swells from WNW to NW, are often consistent, ranging from short to long period.
  • Travel time from one to five days.
  • Peak hurricane season from mid-August through mid-October can offer a variety of swell directions. Recurving tropical cyclones often undergo extratropical transition (most common, October) or enhance developing winter storms. Tropical systems can impact the region with wind and weather, like Cyclone Leslie in October 2018.
  • Local windswell events do occur and can provide fun surf. Events are not as strong as above mentioned swell sources and do not produce the signature XL surf.
The preferred swell source and swell window for Nazare.

Swell Window
  • Nazaré’s swell window is technically open from SW (226°) to N (357°). West to NW angled swells are strongest and most common; WNW swells are ideal.
  • Between the Peniche peninsula at 226° and 251° lies a small group of islands known as the Berlengas Archipelago. A fraction of swell energy filters through these islands and are not as strong as more prominent West-NW swells.
  • Southerly angled swells are usually local windswell events (e.g., ahead of an approaching front), often coinciding with unfavorable onshore wind.
  • Nazaré receives more northerly angled swells up to 357°. North-northwest to N swells are not a favorable direction — shorter period swells generally sweep across the beach, longer period swells see an occasional canyon set that is too crossed up. Wave amplification through refraction by the canyon and associated constructive interference is not as impactful from the north.
Doesn’t look very playful now, does it? And good luck timing the sets.
Photo: Andre Bothelo

Bathymetry

Bathymetry is vital in how waves behave when approaching and breaking along shore, refracting energy into or away from different locations with each variation in swell direction or period.
The surf at certain points can be amplified to greater heights, while other spots are left in a swell void.
And the best spot on the planet to observe extreme wave refraction is Nazaré.

The large, deepwater Nazaré Canyon has the potential to significantly amplify the surf at the beach just to the north of the bay.
Wave-face height can multiply three, four, even five times the offshore deepwater swell height.
But this magnification is highly dependent on the incoming swell angle and period.
Generally, Nazaré favors a longer period swell from the WNW.

Energy in longer period swells extends deeper within the water column, feeling the contours of the ocean bottom sooner, and with a greater degree of effect.
Since swells always refract toward shallower water, longer period swells start to turn and bend sooner and more effectively.


For Nazaré, there is a steep contrast between the large and deep canyon running offshore and the much shallower ridge that lines the northern slope.
This canyon/ridge relationship extends a long distance far offshore all the way up to the break.
The portion of the swell running through the deep canyon maintains a greater percentage of its raw open ocean energy and forward speed closer to shore.
And upon interacting with the adjacent ridge, much of this energy will refract out of the canyon and focus back in toward the break.

The various bends of the canyon also play a role, helping create a more complex scenario of refracting and converging waves.
Meanwhile, the inbound swell traveling over the shallower water north of the canyon starts to gradually slow down and shoal when nearing the coast — and much of this energy focuses toward Nazaré as well.
The result is a compression of these refracting swell lines as they converge at the break, amplifying the waves.

However, there is another key factor at work besides just refractive pileup that helps contribute to the extreme magnification of the waves here, and that is constructive interference (Note – A spot like the Wedge also has this X-factor going on).
After extensive research on the bathymetry, running various swell scenarios through our high-powered computer simulations, and athlete observations, we do know the “magic numbers” for the canyon to perform at its maximum potential.
And the direction is just as important as the period.

From Surfline Labs: Animation (4x normal speed) from Surfline Labs shows the swell that provided the world record wave on November 8th, 2017.
It shows the effects of the Nazare canyon to create mutant, XXL peaks.
The reds indicate peaks, the blues show the troughs — the biggest (red) peaks only appear sporadically when a multitude of factors come perfectly together.
It was timing, and luck, that allowed Ricardo Koxa to catch, and break, the world record wave.


Given the unique layout of this underwater landscape, incoming long period swells from the WNW are ideal for Nazaré.
These swells have just enough west in them to allow the canyon to refract at its fullest potential, yet just enough north that most of the swell is refracting back toward this particular stretch of beach, instead of away to the south.
The north component allows the portion of the swell not running through the canyon to converge with the waves refracting out of the canyon — a combo of NW and SW waves in the surf zone.

If there is too much north in the swell, then the canyon has difficulty refracting swell back toward the north, thus providing less energy and lowering the potential for larger surf.
The sets that do refract from the canyon are almost too peaky with more slopey, mushy shoulders.
There is often more current running on these more northerly angled swells as well.


Monitoring of the Nazaré canyon : Monican observatory

For W to WSW swells, the refracting energy from the canyon is more evenly split to the north and south, also lowering the potential for larger surf at Nazaré.
SW swells are partially shadowed by offshore islands.
The surf is not as peaky on these swells, as west lines north of the canyon square up more to the coast with less convergence from waves refracting from the canyon.
For more southerly angled swells, the canyon refracts more energy to areas to the south, considerably lowering the refracting factor and peaky nature of Nazaré.

A ski is not required to ride this train — until it gets to a certain size.
Photo: Klein

Wind

Like most spots, Nazaré prefers calm or light to moderate offshore wind (east to southeast).
Strong offshore wind can create hazardous conditions and is almost as problematic as an onshore wind, especially in big surf.
Strong offshores make it very difficult to paddle into waves and creates surface chop running up the wave faces.
Bigger, faster-moving waves have a greater opposition to stronger offshore flow, aggravating the sea surface even more.

High pressure overhead or to the north to northeast of Portugal sets up offshore flow for Nazare.

Located on the far southwestern edge of Europe, Nazaré fares better than those at higher latitudes when it comes to severe winter weather.
Systems tracking through the higher latitudes, or storms that lift northward before nearing Europe, can provide good swell with less adverse local weather.

But storms tracking through the lower latitudes can bring poor wind and weather along with swell.
Approaching fronts often bring onshore winds and stormy conditions to the region.
High pressure building in behind these fronts, either over the region or to the north or northeast, turns the wind offshore and improves local weather.
Nazaré can handle light onshores as the waves themselves block the wind on big days and the cliffs shelter the waves from a southerly wind.

The view from the cliff.
Safer than a view from the water.
Photo: Klein

Best Conditions for Nazaré
  • Best Tide: Mid, prefers incoming
  • Best Swell Direction: West-Northwest to Northwest
  • Best Swell Period: Longer period
  • Best Wind: Calm or light to moderate offshore (east-southeast)
  • Best Size: Works on all sizes, no limit on max size
  • Best Season: Fall generally best, winter and spring very solid too
  • Resources for Nazaré
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Wednesday, December 12, 2018

Sails make a comeback as shipping tries to go green

Car manufacturer, Groupe Renault, is partnering with French designer and operator of cargo sailing ships, NeoLine, to reduce the carbon footprint of the Group’s supply chain.
NeoLine has designed a 136-meter ro-ro with 4,200 square meters of sail area it says has the potential to reduce CO2 emissions by up to 90 percent through the use of wind power primarily, combined with a cost-cutting speed and optimized energy mix. commission the vessels by 2020-2021 on a pilot route joining Saint-Nazaire in France, the U.S. Eastern seaboard and Saint-Pierre and Miquelon (off the coast of Newfoundland in Canada).

From The Sentinel by Kelvin Chan

As the shipping industry faces pressure to cut climate-altering greenhouse gases, one answer is blowing in the wind.

European and U.S. tech companies, including one backed by airplane maker Airbus, are pitching futuristic sails to help cargo ships harness the free and endless supply of wind power.
While they sometimes don't even look like sails -- some are shaped like spinning columns -- they represent a cheap and reliable way to reduce CO2 emissions for an industry that depends on a particularly dirty form of fossil fuels.

The merchant shipping industry releases 2.2% of the world’s carbon emissions, about the same as Germany, and the International Maritime Organization estimates that could increase up to 250% by 2050 if no action is taken.
Finnish company Norsepower may have a solution in the spinning cylinders they’ve designed for ships to harness wind power and produce forward thrust.
The result is a ship that needs less fuel to travel the seas - a major boost to the industry that transports 90% of international trade.
VICE News took a ride on the Estraden, a cargo ship fitted with Norsepower Rotor Sails, to see the technology that can reduce a ship’s carbon emissions by 1000 tons per year.
If all 50,000 merchant ships adopted Norsepower Rotor Sails, the costs saved on fuel would be over $7 billion a year, and the emissions prevented would equal more than 12 coal fired power plants.
While zero emission ships could be achieved using Rotor Sails paired with other alternative fuel sources, the economic incentives haven’t been strong enough to mobilize the industry just yet.
But strides such as those taken by Norsepower could help kickstart a widescale greening of the industry.

"It's an old technology," said Tuomas Riski, the CEO of Finland's Norsepower, which added its "rotor sail" technology for the first time to a tanker in August.
"Our vision is that sails are coming back to the seas."

Denmark's Maersk Tankers is using its Maersk Pelican oil tanker to test Norsepower's 30 meter (98 foot) deck-mounted spinning columns, which convert wind into thrust based on an idea first floated nearly a century ago.

Separately, A.P. Moller-Maersk, which shares the same owner and is the world's biggest container shipping company, pledged this week to cut carbon emissions to zero by 2050, which will require developing commercially viable carbon neutral vessels by the end of next decade.

This is Enercon's E-Ship 1 128m cargo vessel built in 2010 designed for the transportation of wind turbine components. She is a most unusual looking ship featuring four 27m tall Flettner Rotor Sails which rotate rapidly, due to the magnus effect this design helps reduce engine fuel costs with greater efficiency.

The shipping sector's interest in "sail tech" and other ideas took on greater urgency after the International Maritime Organization, the U.N.'s maritime agency, reached an agreement in April to slash emissions by 50 percent by 2050.

Transport's contribution to earth-warming emissions are in focus as negotiators in Katowice, Poland, gather for U.N. talks to hash out the details of the 2015 Paris accord on curbing global warming.

Beluga Projects SkySails

Shipping, like aviation, isn't covered by the Paris agreement because of the difficulty attributing their emissions to individual nations, but environmental activists say industry efforts are needed.
Ships belch out nearly 1 billion tons of carbon dioxide a year, accounting for 2-3 percent of global greenhouse gases. The emissions are projected to grow between 50 to 250 percent by 2050 if no action is taken.

Notoriously resistant to change, the shipping industry is facing up to the need to cut its use of cheap but dirty "bunker fuel" that powers the global fleet of 50,000 vessels -- the backbone of world trade.

The IMO is taking aim more broadly at pollution, requiring ships to start using low-sulfur fuel in 2020 and sending ship owners scrambling to invest in smokestack scrubbers, which clean exhaust, or looking at cleaner but pricier distillate fuels.

The GoodShipping Program is the world’s first initiative to decarbonize container shipping by changing the marine fuel mix – switching from heavy fuel oil towards sustainable marine fuel.
The Program enables cargo owners to make a change: their footprint from shipping will be reduced significantly, regardless of existing contracts, cargo routes and volumes.

A Dutch group, the Goodshipping Program , is trying biofuel, which is made from organic matter.
It refueled a container vessel in September with 22,000 liters of used cooking oil, cutting carbon dioxide emissions by 40 tons.

In Norway, efforts to electrify maritime vessels are gathering pace, highlighted by the launch of the world's first all-electric passenger ferry, Future of the Fjords, in April.
Chemical maker Yara is meanwhile planning to build a battery-powered autonomous container ship to ferry fertilizer between plant and port.
Ship owners have to move with the times, said Bjorn Tore Orvik, Yara's project leader.
Building a conventional fossil-fueled vessel "is a bigger risk than actually looking to new technologies ... because if new legislation suddenly appears then your ship is out of date," said Orvik.

Batteries are effective for coastal shipping, though not for long-distance sea voyages, so the industry will need to consider other "energy carriers" generated from renewable power, such as hydrogen or ammonia, said Jan Kjetil Paulsen, an advisor at the Bellona Foundation, an environmental non-government organization.
Wind power is also feasible, especially if vessels sail more slowly.
"That is where the big challenge lies today," said Paulsen.

The performance of the EcoFlettner, which has been tested on the MV Fehn Pollux since July, clearly exceeds the expectations of the scientists.
“The data we have evaluated so far signifcantly outmatch those of our model calculations,” says Professor Michael Vahs, who has been researching the topic of wind propulsion for seagoing vessels at the University of Applied Science Emden / Leer for more than 15 years.
“In perfect conditions, this prototype delivers more thrust than the main engine.”
15 companies from around Leer have been involved in the development and construction of the sailing system. The whole project is funded by the EU and coordinated by Mariko in Leer.
The rotor is 18 meters high and has a diameter of three meters.
After lengthy test runs ashore, the rotor is now being tested under real conditions aboard 90- meter-long multi-purpose freighter MV Fehn Pollux.
On board MV Fehn Pollux more than 50 different data are continuously collected and computed in real time by the Flettner control system on the bridge.
The computer uses the data to calculate the optimum settings for the rotor under the current conditions.

Wind power looks to hold the most promise.
The technology behind Norsepower's rotor sails, also known as Flettner rotors, is based on the principle that airflow speeds up on one side of a spinning object and slows on the other.
That creates a force that can be harnessed.

Rotor sails can generate thrust even from wind coming from the side of a ship.
German engineer Anton Flettner pioneered the idea in the 1920s but the concept languished because it couldn't compete with cheap oil.
On a windy day, Norsepower says rotors can replace up to 50 percent of a ship's engine propulsion. Overall, the company says it can cut fuel consumption by 7 to 10 percent.

Maersk Pelican: Trialling a pair of Norsepower Rotors under trading conditions

Maersk Tankers said the rotor sails have helped the Pelican use less engine power or go faster on its travels across, resulting in better fuel efficiency, though it didn't give specific figures.

One big problem with rotors is they get in the way of port cranes that load and unload cargo.
To get around that, U.S. startup Magnuss has developed a retractable version.
The New York-based company is raising $10 million to build its concept, which involves two 50-foot (15-meter) steel cylinders that retract below deck.
"It's just a better mousetrap," said CEO James Rhodes, who says his target market is the "Panamax" size bulk cargo ships carrying iron ore, coal or grain.


High tech versions of conventional sails are also on the drawing board.
Spain's bound4blue's aircraft wing-like sail and collapses like an accordion, according to a video of a scaled-down version from a recent trade fair.
The first two will be installed next year followed by five more in 2020.
The company is in talks with 15 more ship owners from across Europe, Japan, China and the U.S. to install its technology, said co-founder Cristina Aleixendrei.

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