Monday, August 5, 2019

Saildrone launched with seafloor mapping capabilities in the Gulf of Mexico shows promise for remote Arctic mapping

Rear Adm. Shepard M. Smith, director of NOAA’s Office of Coast Survey, Richard Jenkins, co-founder and CEO Saildrone, Brian Connon, director of USM’s Hydrographic Science Research Center.
Saildrone USV during its initial mission in the Gulf of Mexico.
Credit: Saildrone

From NOAA

NOAA’s Office of Coast Survey, the University of Southern Mississippi (USM), and Saildrone accomplished a key milestone in the research and testing of unmanned technology that can lead to enhanced seafloor mapping capabilities with the launch of the first Saildrone — a wind-driven and solar-powered unmanned surface vehicle (USV) — equipped with multibeam echo sounder technology in the Gulf of Mexico.
NOAA anticipates the success of this mission and technical achievement will lead to mapping projects in the Arctic.

Though it only has 25 robots deployed, Saildrone founder Richard Jenkins says the company is already selling forecasts to sports teams, insurance companies and hedge funds
"The ocean is driving our weather, and both the climate and the oceans are changing rapidly. We have to understand that."

“The operational deployment of multibeam technology on a Saildrone in the Gulf of Mexico and subsequent data output puts us closer toward the use of autonomous systems to map critical areas such as the Arctic,” said Rear Adm. Shepard M. Smith, director of NOAA’s Office of Coast Survey, “the potential for ocean mapping is extraordinary.”

The Saildrone USV was deployed into the Gulf on June 25 for its initial data collection mission and ran for 8 days.
After evaluating the data collected by the USV and making some software improvements, USM launched the vehicle again on July 19 and recovered on June 22.

“These two missions provided great insight into the potential for this technology for ocean mapping, said Brian Connon, director of USM’s Hydrographic Science Research Center, “success of these missions and advancements in this technology are due to collaboration among government, academia, and the private sector.”

Launching the first Saildrone USV mapping mission using multibeam echo sounder technology was not without its challenges.
The mission achieved three primary technological advancements in the areas of power management, communication, and automation; all critical for a mission in the Arctic where operational resources are not readily available.

Hydrographic survey systems were originally designed to run from larger ships that have power resources.
On a long-duration unmanned vehicle power is limited, and in this case, harnessed from the sun.
This creates limitations in data collection.
Saildrone worked with Norbit, the multibeam sonar manufacturer, to create an efficient system that is capable of high resolution data collection on a tight power budget.

Communication can also pose an issue on long-duration USVs.
Sending the USV commands, whether to change navigation patterns or adjust the sonar, is conducted via satellite.
The challenge is understanding what the sonar is doing while out at sea.
It is a complex instrument and coding for it remotely has proven possible on these missions.

Autonomous, ocean-going vessels have been launched from Alaska for oceanic research in the Bering Sea. NOAA has partnered with Saildrone, Inc. to monitor the vital signs of the sea–wind, temperature and salinity, to take a look at important Walleye pollock fish stocks, track Northern fur seals and locate right whales through sound.

Finally, determining data quality is a challenge.
It is not possible for the system to send the data in its entirety back to the operator via satellite for real-time evaluation.
So data quality must be determined another way while it is operating remotely.
This is an evolving area of remote operation and one that automation and the ability of the sonar to “self-correct” will play a critical role.

Over all, autonomous solutions can be far more efficient than traditional methods of hydrographic surveys.
Unmanned vehicles can be deployed from almost anywhere.
Their state of the art guidance systems speed survey progress, and reduce the need for infill lines.
Autonomous systems can access areas that are either too hazardous or too difficult for conventional vessels to get to, expanding the extent of survey coverage and enabling safer operations.


“Unmanned systems such as Saildrone, paired with multibeam technologies, are the future of exploration in remote or difficult to reach areas and provides a more efficient survey option,” said Richard Jenkins, CEO of Saildrone.
USM and Saildrone collaborated to configure the USV for this mission under a grant provided by NOAA’s Office of Coast Survey.
Saildrone develops and manufactures autonomous sailing drones, with a wide range of capabilities including providing high quality oceanic and atmospheric observations.


NOAA partners with Saildrone in other capacities such as data collection for fisheries management and weather/climate forecasting.
The Hydrographic Science Research Center here at the University of Southern Mississippi works to expand the use of autonomy technology in seabed mapping and ocean cartography.
The center performs research funded by grants through the Northern Gulf Institute.

Links :

Sunday, August 4, 2019

“Skandalopetra” : when in Greece, dive as the Greeks

“Skandalopetra” is freediving with a stone-plate (“petra”) as a ballast, which in turn is attached with a rope to the boat.
This method was used by Greek sponge-divers to descend to the ocean floor to collect sponges.
A few pulls on the rope by the freediver indicated to the Kolizeri (rope-guy on the boat) to bring him back to the surface.
Modern-day Skandalopetra as a sport is done in a bathing-suit and nose clip (and no sponges are involved). No wetsuit, mask or fins are allowed.
The biggest challenge?
The ever-present thermocline in Greek waters, as it hits you like a brick wall, and makes equalization a serious issue.
No wonder all the traditional sponge-divers had permanently damaged eardrums.
Sponge diving was mainly practiced in Kalymnos and Symi (both near Rhodes in the Aegean Sea).

Saturday, August 3, 2019

Rolex Fastnet Race 2019

2019 marks the 48th edition of biennial Rolex Fastnet Race.
Organised by the Royal Ocean Racing Club since 1925 and partnered by Rolex since 2001, the 605nm race is a classic examination of strategy and skill.
Attracting a mix of passionate Corinthians and professionals, this is offshore racing at its very best, with complex weather patterns and testing tidal currents to be negotiated.
For Rolex, this type of sailing challenge lies at the heart of its enduring six-decade-long support for the sport.

On Saturday, 3 August an intrepid fleet of 400 yachts will set sail from Cowes, on the south coast of the United Kingdom, bound for the Fastnet Rock off southern Ireland and the return. leg to the finish in Plymouth.
photo : Carlo Borlenghi

"Sea Fever: For Those in Peril" - Fastnet Race Disaster, 1979 from Hidden Picture Productions
This is a short extract from the 60' programme "For Those in Peril" that Jonathan directed for BBC4. First transmitted as part of the BBC's "Sea Fever" season, the film tells the story of the evolution of coastal rescue in the UK from the start of the 20th century.

 Royal Navy Honors 40th Anniversary of the Fastnet Race Rescue :
This extract tells the story of the Fastnet race disaster of 1979 (so 40 years ago) that launched the biggest maritime rescue operation since Dunkirk.
A freakish storm turned the Celtic Sea into a terrifying washing machine that tossed the 303 entrants about and killed 15 sailors.
This documentary is a tribute to the Royal Navy rescue crews and has a focus on Nick Ward's experience on the Holland Half Tonner Grimalken, and which is recounted in his book "Left for Dead".
The documentary includes some footage from the start of the infamous race, and look out for a shot of the top boat of the Admiral's Cup that year (of which the Fastnet Race was the series finale), the Peterson 39 Eclipse, just to windward of the star performer from the 1977 series, Imp.
You can also see the Irish yacht Golden Apple of the Sun being towed into Plymouth after she had lost her rudder in the storm.
Her crew were airlifted off the boat and she was recovered by the Royal Navy 20 hours after the storm's height.

Links :

Friday, August 2, 2019

Greenland is melting away before our eyes

Temperatures in the 49th state are rising twice as fast as the rest of the world, causing water levels to rise and endangering places of natural beauty.

From RollingStone by Eric Holthaus

“I have my fingers crossed for it not being washed away”

Amid an ongoing heat wave, new data show the Greenland ice sheet is in the middle of its biggest melt season in recorded history.
It’s the latest worrying signal climate change is accelerating far beyond the worst fears of even climate scientists.

 The heatwave that smashed high temperature records in five European countries a week back is now over Greenland, accelerating the melting of the island's ice sheet and causing massive ice loss in the Arctic.

The record-setting heat wave that sweltered northern Europe last week has moved north over the critically vulnerable Greenland ice sheet, triggering temperatures this week that are as much as 25 to 30 degrees Fahrenheit warmer than normal.
Weather models indicate Tuesday’s temperature may have surpassed 75 degrees Fahrenheit in some regions of Greenland, and a weather balloon launched near the capital Nuuk measured all-time record warmth just above the surface.
That heat wave is still intensifying, and is expected to peak on Thursday with the biggest single-day melt ever recorded in Greenland.
On August 1 alone, more than 12 billion tons of water will permanently melt away from the ice sheet and find its way down to the ocean, irreversibly raising sea levels globally.

A tweet from the Danish Meteorological Institute, the official weather service of Greenland, said “almost all the ice sheet, including Summit” measurably melted on Tuesday.
According to a preliminary estimate, that melt covered 87 percent of the ice sheet’s surface, which would be the second-biggest melt day in Greenland’s recorded history.
Separate weather monitoring equipment at Summit Camp at the top of the 10,000-foot-thick Greenland ice sheet confirmed the temperature briefly reached the melting point.

 This river is in West Greenland, close to the capital Nuuk.

Localization with the GeoGarage platform (DGA nautical chart)

Downhill, meltwater was seen dramatically streaming off the edge of the ice sheet in massive waterfalls.
Climate scientist Irina Overeem, who placed a meltwater monitoring station in western Greenland eight years ago, recorded a dramatic video of a rushing torrent of water.
In a comment posted on Twitter, she said “I have my fingers crossed for it not being washed away.” In an email to Rolling Stone, Overeem described the nature of life in Greenland these days: After recording that video, she spotted a warning of the major glacial water runoff on the announcement board of the main supermarket in the capital city.
A similar glacial flood in 2012 was so intense it washed away bridge.

Flying over Greenland last week, impressive huge rivers on the west coast.

Ice core records show melt days like these have happened only a handful of times in the past 1,000 years.
But, with the advent of human-caused climate change, the chances of these full-scale melt events happening are sharply increasing.

Even just a few decades ago, an event like this would have been unthinkable.
Now, island-wide meltdown days like this are becoming increasingly routine.
The ongoing melt event is the second time in seven years that virtually the entire ice sheet simultaneously experienced at least some melt.
The last was in July 2012, where 97 percent of the ice sheet simultaneously melted.

In the 1980s, wintertime snows in Greenland roughly balanced summertime melt from the ice sheet, and the conventional wisdom among scientists was that it might take thousands of years for the ice to completely melt under pressure from global warming.

 A satellite image shows melt ponds on the surface of the northeastern Greenland ice sheet on July 30.
(ESA/Sentinel-2)

That’s all changed now.

With a decade or two of hindsight, scientists now believe Greenland passed an important tipping point around 2003, and since then its melt rate has more than quadrupled.
This week alone, Greenland will lose about 50 billion tons of ice, enough for a permanent rise in global sea levels by about 0.1mm.
So far in July, the Greenland ice sheet has lost 160 billion tons of ice — enough to cover Florida in about six feet of water.
According to IPCC estimates, that’s roughly the level of melt a typical summer will have in 2050 under the worst-case warming scenario if we don’t take meaningful action to address climate change.
Under that same scenario, this week’s brutal, deadly heat wave would be normal weather in the 2070s.


This animated gif shows the mass Greenland's Jakobshavn Glacier has gained from 2016-17, 2017-18 and 2018-19.
Areas with the most growth — about 33 yards (30 meters) — are shown in dark blue.
Red areas represent thinning.
The images were produced using GLISTIN-A radar data as part of NASA's Ocean's Melting Greenland (OMG) mission.
More information on OMG can be found here: https://omg.jpl.nasa.gov/portal/.
Credit: NASA/JPL-Caltech / NASA Earth Observatory
 Greenland's Jakobshavn Glacier

Xavier Fettweis, a polar scientist at the University of Liège in Belgium who tracks meltwater on the Greenland ice sheet, told Rolling Stone in an email that the recent acceleration of these melt events means the IPCC scenarios “clearly underestimate what we currently observe over the Greenland ice sheet” and should revisit their projections for the future.

“This melt event is a good alarm signal that we urgently need change our way of living,” said Fettweis.
“It is more and more likely that the IPCC projections are too optimistic in the Arctic.”
Altogether, the Greenland ice sheet contains enough ice to raise global sea levels by about 24 feet.

 Melt ponds in Western Greenland, active 2019 wildfire and 2017 wildfire burn scar (August 1, 2019)
Cpernicus sentinel-3
 courtesy of @Pierre_Markuse

Unusual wildfires across Siberia, Scandinavia, Alaska, and Greenland have been raging all summer, and by one estimate released about 50 million tons of carbon dioxide in the month of June alone — equivalent to the annual emissions of Sweden.
In Switzerland, some glaciers melted so rapidly during last week’s heatwave that they sent swirling mudflows racing downhill.
In the Arctic Ocean, sea ice is at a record-low extent as the melt season continues to lengthen.
In Alaska, ecosystems are rapidly changing, especially in the Bering Sea region where this year’s ice-free season began in February.

About 200 million tons of sediment enter the Sermilik Fjord in southwestern Greenland every year. Mining just some of it could make Greenland a major exporter of sand to the world.

As daunting as this is, the latest science on Greenland also points to a window of hope: Greenland’s meltdown is not yet irreversible.
That self-sustaining process of melt-begetting-more-melt would kick in at around 1.5 or 2 degrees Celsius of global warming.
That means whether or not Greenland’s ice sheet melts completely is almost entirely in human control: A full-scale mobilization ­— including rapidly transforming the basis of the global economy toward a future where fossil fuels are no longer used — would probably be enough to keep most of the remaining ice frozen, where it belongs.

Links :

Thursday, August 1, 2019

New Zealand (Linz) update in the GeoGarage platform

21 nautical raster charts updated & 1 new chart added