Saturday, May 28, 2016

Ten-year gap in major hurricanes continues

 Improving hurricane forecasts means testing historical storms with today's sophisticated models and supercomputers. NASA and NOAA work together in gathering ground and satellite observations, as well as experimenting with research forecast models.
As a result of this collaboration, model resolution has increased, and scientists are discovering more about the processes that occur within these powerful storms.
The Global Precipitation Measurement (GPM) Mission is a joint NASA and Japan Aerospace Exploration Agency (JAXA) mission that measures all forms of precipitation around the globe. GPMs Microwave Imager, or GMI, has proven useful in seeing beneath the swirling clouds and into the structure of tropical cyclones.
The information gathered by GPM and other missions will be used to improve forecast models.
Credit: NASA Goddard/Ryan Fitzgibbons 

Could the first tropical storm of the Atlantic hurricane season
break the 10-year “hurricane drought” record?

Friday, May 27, 2016

Recreational boating fatalities decreasing

This video was made for AV-OG-TIL a Norwegian NGO,
working to reduce the harmful effects of alcohol.
The aim is to raise awareness around the dangers of intoxication while operating a boat, when pregnant or together with children.
Docking is an art form best practiced sober.

From Maritime Executive

May 21 – 27 was North American Safe Boating Awareness Week

The U.S. Coast Guard released its 2015 Recreational Boating Statistics report last Tuesday, revealing that boating fatalities nationwide that year totaled 626, the third-lowest number of yearly boating fatalities on record.

From 2014 to 2015,
  • injuries decreased from 2,678 to 2,613, a 2.4 percent decrease;
  • deaths increased from 610 to 626, a 2.6 percent increase;
  • and the total number of accidents increased from 4,064 to 4,158, a 2.3 percent increase.

 About the importance of wearing a life jacket :
The National Safe Boating Council created a new public service announcement campaign, “Silly Humans,” featuring Shaw Grigsby, Bassmaster Elite Series Angler and host of “One More Cast” on The Sportsman Channel.
This light-hearted campaign follows two fish who think they are smarter than some humans, but they are no match for an accomplished angler who boats responsibly and wears a life jacket.
“If you’re not a fish, you’ve got to wear your life jacket,” reminds Grigsby.

The report also shows that in 2015:
  • The fatality rate of 5.3 deaths per 100,000 registered recreational vessels reflected a 1.9 percent increase from the previous year's rate of 5.2 deaths per 100,000 registered recreational vessels.
  • Twenty-two children under age 13 died while boating that year. Twelve children (55 percent) died from drowning. Two children (17 percent) of those who drowned were wearing a life jacket; half of the remaining 10 children who were not wearing a life jacket were not required to do so under state law.
  • Property damage totaled approximately $42 million.
  • Alcohol was the leading known contributing factor in fatal boating accidents and was listed as the leading factor in 17 percent of deaths.
  • Operator inattention, operator inexperience, improper lookout, machinery failure and excessive speed ranked as the top five primary contributing factors in accidents.
You rock !
Where the cause of death was known, 76 percent of fatal boating accident victims drowned; of those drowning victims, 85 percent were not wearing a life jacket.
Where boating instruction was known, 71 percent of deaths occurred on vessels where the operator had not received boating safety instruction.
The most common types of vessels involved in reported accidents were open motorboats, personal watercraft and cabin motorboats.
The vessel types with the highest number of fatalities were on open motorboats, kayaks and canoes.


The Coast Guard reminds all boaters to boat responsibly while on the water: wear a life jacket, take a boating safety course, attach your engine cut-off switch, get a free vessel safety check and avoid alcohol or other impairing substance consumption.

The Coast Guard also encourages the use of the safe boating application available on most smart phones.
The phone application can help boaters request safe boating information, request safety checks, file a float plan, review navigation rules, report hazards or pollution and request emergency situation. Although the safe boating application is a great tool, it is still recommended to have a marine VHF-FM radio installed on your boat or carry a handheld version.
Calling on VHF-FM radio is the most reliable way to call for help in case of an emergency.

Thursday, May 26, 2016

Major fishing deal offers protection to Arctic waters

The agreement is the first time the seafood sector has voluntarily imposed limitations to industrial fishing in the Arctic.
Photograph: Matthew Lloyd/Bloomberg/Getty Images

From The Guardian by Jessica Aldred

Leading seafood suppliers, including McDonald’s, Tesco and Birds Eye, say suppliers won’t expand cod fisheries into pristine Arctic region

Fishermen and seafood suppliers struck a major deal on Wednesday that will protect a key Arctic region from industrial fishing for cod.
Companies including McDonald’s, Tesco, Birds Eye, Europe’s largest frozen fish processor, Espersen, Russian group Karat, and Fiskebåt, which represents the entire Norwegian oceangoing fishing fleet, have said their suppliers will refrain from expanding their cod fisheries further into pristine Arctic waters.
“From the 2016 season the catching sector will not expand their cod fishing activities with trawl gear into those areas where regular fishing has not taken place before,” the deal reads.
The agreement follows an investigation by Greenpeace in March which revealed that suppliers of cod to major British seafood brands were taking advantage of melting Arctic ice to push further north with fleets of destructive giant bottom trawlers.
Using satellite tracking data, it found that an increasing number of Russian and Norwegian trawlers had fished in the northern Barents Sea around Svalbard in the past three years, an area deemed by scientists to be ecologically significant.

  This vessel was photographed operating in Bellsund within the borders of the national park on the west coast of Spitsbergen.
Photograph: Nick Cobbing/Greenpeace

The region, which includes the Svalbard archipelago - the “Arctic Galapagos”, is home to vulnerable species including the polar bear, bowhead whale and Greenland shark.
Experts consider bottom trawlers - often dubbed giant “bulldozers” - to be a highly destructive fishing method, which is already responsible for damaging up to half of Norway’s coldwater corals reefs.
Marine conservation biologist Prof Callum Roberts said: “Over the last 200 years it has converted once rich and complex seabed habitats to endless expanses of shifting sands and mud. Areas of the Arctic protected by sea ice represent one of the last pristine refuges from trawling and need urgent protection to prevent them from suffering the same fate.”

The area of the Barents Sea covered by the agreement is adjacent to major fishing grounds where at least 70% of all the Atlantic cod that ends up on dinner plates around the world comes from.
The agreement, which spans the whole supply chain and covers an area twice the size of France, is the first time the seafood sector has voluntarily imposed limitations to industrial fishing in the Arctic. Any fishing companies operating in these pristine Arctic waters will not be able to sell their cod to the brands supporting this agreement.

 Map of the area of northern Barents Sea including the waters around Svalbard where some of the world’s largest seafood and fishing companies have committed not to expand their search for cod into.
Photograph: Greenpeace 

Greenpeace UK campaigner, Daniela Montalto, said: “This is a major step in the right direction. This unprecedented alliance have today taken a stand for the fragile Arctic environment, and set an important precedent for other industries eyeing up this region. The challenge for these companies is now to deliver on their commitment to Arctic protection and show real results out on the water. The melting ice should be a stark warning of the dangers of climate change, not an opportunity to plunder this fragile ecosystem.”

Giles Bolton, responsible sourcing director for Tesco, said: “Our customers tell us it’s important they can be sure the fish on our shelves is caught in a way that doesn’t harm the ocean environment, and this landmark agreement means vulnerable marine life in the Barents and Norwegian seas will be protected. We will keep working with our suppliers, relevant authorities and NGOs to help safeguard this unique marine habitat for future generations.”

The deal comes after a record low for Arctic sea ice this winter.
A huge expanse of the Arctic sea never froze over and remained open water as a season of freakishly high temperatures produced deep – and likely irreversible – changes on the far north.

Currently there is no law in place to protect Arctic areas that were once covered by ice.
Greenpeace welcomed the “temporary stop-gap” the agreement brought but warned that large areas of water left open for longer periods made an urgent case for legal protection by the Norwegian government.
“The Norwegian government must now acknowledge the growing resistance to reckless exploitation of the fragile Arctic environment, not only from the millions of people around the world who want the Arctic protected but also from the corporate world. Now is the time to take concrete steps towards legal protection of Svalbard and the northern Barents Sea so that Norway can meet its international obligation for marine protection,” Montalto said.

Links :

Wednesday, May 25, 2016

Squids and octopuses — the ‘weeds of the sea’ — are on the rise

(The National Aquarium of New Zealand via AP)

From The Washington Post by Rachel Feltman

I for one welcome our cephalopod overlords.
The number of cephalopods — squid, octopus and other squishy sea aliens — has shot up over the past six decades, even as humanity's influence on the ocean (read: climate change, pollution and overfishing) has caused many marine populations to plummet, according to a study published Monday in Current Biology.

 Japan: Giant deep sea squid swims in bay

In other words, the ocean is becoming a more difficult place to live — and all of that empty space means everything is coming up octopus.
"Cephalopods are often called 'weeds of the sea' as they have a unique set of biological traits, including rapid growth, short lifespans and flexible development," study author Zoë Doubleday of the University of Adelaide said in a statement.
"These allow them to adapt to changing environmental conditions (such as temperature) more quickly than many other marine species, which suggests that they may be benefiting from a changing ocean environment."

The researchers analyzed the rate at which cephalopods have shown up in fishing catches or sampling efforts from 1953 to 2013.
The study included 35 cephalopod species or genera representing six families.
As a whole, they found that the group was thriving and becoming more prolific.

Giant Australian cuttlefish in Spencer Gulf, South Australia. (Scott Portelli)

Doubleday didn't set out trying to show that these populations were booming.
In fact, she and her colleagues were troubled by the apparent decline of the giant Australian cuttlefish.
Luckily, it looks as if things are on the up-and-up for that population as well.
"To determine if similar patterns were occurring elsewhere, we compiled this global-scale database," she explained. "Surprisingly, analyses revealed that cephalopods, as a whole, are in fact increasing; and since this study, cuttlefish numbers from this iconic population near Whyalla are luckily bouncing back."

But while that's great news for the giant Australian cuttlefish, scientists aren't so sure how to feel about an ocean where squid, cuttlefish and other octopods are all on the rise.
“I guess if you're a squid or octopus fisherman, these increases may seem like a great thing,” Benjamin Halpern from the University of California, who wasn't involved in the study, told the Atlantic magazine.
“But such dramatic global changes are quite worrisome. When we change the oceans this much, we move things into a new state — one that we know much less about. We might have more squid on our plates in the short run. What are we risking losing in the long run?”

The point is that we don't really know how an influx of these voracious predators will change the ocean — and that's a little scary.
So should we prepare for a future with a lot more tentacles?
That's unlikely.
Cephalopods may be super versatile, but their population booms are expected to rise and fall in a pretty self-regulating fashion — as was the case with the giant Australian cuttlefish.
In fact, the researchers don't think cephalopods are necessarily safe from the same overfishing that's helped them prosper.
It "will be critical to manage cephalopod stocks appropriately so they do not face the same fate as many of their longer-lived counterparts," they write in the study.

Links :

Tuesday, May 24, 2016

‘Biodegradable’ plastics are a big fat lie

 Sailing seas of plastic :
How much plastic is floating in our oceans ?

From HuffingtonPost by Chris d'Angelo

A prediction that the world’s oceans will contain more plastic than fish by 2050 is likely to intensify the push for sustainable, environmentally friendly alternatives.
Biodegradable plastics have long been touted as a “greener” technology, but a new report from the United Nations says these plastics do little, if anything, to actually protect the planet and marine creatures.
“Plastics marked as ‘biodegradable’ do not degrade rapidly in the ocean,” says the report, published Monday.

 Lemon shark is pictured with plastic bag caught around its gills in the Bahamas 
Jonathan Bird via Getty Images

The 179-page report on plastic marine debris is one of several documents released in time for the United Nations Environment Assembly, which kicked off Monday in Nairobi, Kenya.
Plastics, which can cause serious ecological harm, “are now ubiquitous in the ocean, found in every ocean and on every shoreline from the Arctic through the tropics to the Antarctic,” the report states.
Biodegradable plastics — which have been used for shopping bags, water bottles and food containers — are designed to be less durable and capable of degrading quickly in the environment. But the problem, according to the U.N., is that the conditions required for such plastics to break down exist almost exclusively in industrial composters, not in the ocean.
The description is “well-intentioned but wrong,” Jacqueline McGlade, chief scientist at the U.N. Environment Program, told The Guardian.
“A lot of plastics labelled biodegradable, like shopping bags, will only break down in temperatures of [122 degrees Fahrenheit] and that is not the ocean,” McGlade told the publication.
“They are also not buoyant, so they’re going to sink, so they’re not going to be exposed to UV and break down.”

 Plastic garbage is pictured on Eastern Island, in the Northwest Hawaiian Islands.
Roberta Olenick via Getty Images

The U.N. estimates that global plastic production grew 4 percent from 2013 to 2014, exceeding 311 million metric tons. At least 8 million metric tons — the equivalent of one garbage truck every minute — leak into the ocean each year, according to the World Economic Forum.
The U.N. says improving waste collection and management is the “most urgent solution” to reducing plastic litter, but social attitudes are also critical.
“There is a moral argument that we should not allow the ocean to become further polluted with plastic waste, and that marine littering should be considered a ‘common concern of humankind,’” the report says.
In other words, don’t pat yourself on the back the next time you reach for those biodegradable plastic bags.
We need to do a lot more than that.

Links :

Monday, May 23, 2016

How can modern satellites photos possibly be accurate to 20 centimeters in 10 kilometers?

3D WorldView-1 satellite view showing some of the ground survey points in PhotoSat’s Eritrea test area.

 From GIScafé by Gerry Mitchell (Photosat)

My intuition rebels at the notion that a satellite orbiting 750 kilometers above the earth, traveling at 7 kilometers per second could possibly take photos of the ground accurate to 20 centimeters in 10 kilometers.
When I realize that these satellites have scanning cameras which take their photos like push brooms, with the north end of the photo taken a few milliseconds before or after the south end, and that the whole satellite is vibrating while the photos are taken, my mind boggles.
It just does not seem that such high accuracy should be possible.
The satellite photos themselves, checked with tens of thousands of ground survey points, clearly demonstrate that the accuracy is real.

How do the satellites and cameras work?

We engineers and geoscientists in the commercial realm don’t actually know how these satellites and cameras really work.
Almost all of the technical details of the imaging satellites, their cameras and their ground processing stations, are classified.
Or if they are not classified they are certainly very difficult to discover.
I have had many conversations with satellite engineers who seem like they would love to tell me why their satellites perform so amazingly well.
However, sadly, they are not allowed to.
They simply can’t discuss classified technology with anyone who doesn't have the appropriate security clearances.

Whenever I have one of these conversations it always seems to me that part of what the engineer knows is public and part is classified but the engineer cannot be sure that he or she can remember what is still classified and what isn’t.
Since the engineers don’t have perfect memories it is safest to say nothing.
I have had satellite engineers decline to confirm information that is published on their own company’s websites.
This can make for some very awkward conversations.
We engineers and geoscientists in the commercial world only have access to the satellite photos themselves and very general public information about the satellites and their cameras.

How accurate are the satellite photos?

When the Digital Globe WorldView-1 ( WV1) satellite photos first became commercially available in 2008, PhotoSat acquired stereo photos for a test area in and Eritrea where we had over 45,000 precisely surveyed ground points.
When we shifted the WV1 photos three meters horizontally to match any survey point we were amazed to discover that all of the survey points within 10 kilometers matched the satellite photos to within 20 centimeters.
We eventually documented this discovery in an accuracy study white paper that we presented at conferences and is now published on our web site.

Now, eight years after that initial WorldView-1 accuracy study of the Eritrea test area, we have processed hundreds of satellite photos from the WorldView, Pleiades, SPOT and KOMPSAT satellites and have come to expect this incredible accuracy.
I am still in awe that this is possible and I still don’t know how it is achieved.
I do know that the photos are amazingly accurate.

WorldView-1 satellite photo over the PhotoSat test area in Eritrea.
The over 15,000 ground survey points used to confirm that the satellite photo accuracy is better than 20 centimeters in 10 kilometers are shown as black dots.
The completely black areas are survey points every 20 meters along lines separated by 100 meters.

Colour image of a one meter PhotoSat survey grid produced from the WorldView-1 satellite photos.  The ground survey points demonstrate that the PhotoSat grid is accurate to 35 centimeters in elevation.

Sunday, May 22, 2016

Cavitation explained

Cavitation is the formation of vapour cavities in a liquid – i.e. small liquid-free zones ("bubbles" or "voids") – that are the consequence of forces acting upon the liquid. 
t usually occurs when a liquid is subjected to rapid changes of pressure that cause the formation of cavities where the pressure is relatively low.
When subjected to higher pressure, the voids implode and can generate an intense shock wave.