Walls of perception

Levi Siver's segment from Walls of Perception from Levi Siver

To ride is to be passionate about nature.You have to face nature the way it is, pit your strength against it, and stand in front of it humble and confident at the same time.
Nature is wild and unpredictable.
You can’t cheat nature…

Building on the success of the 2010 release, The Watermen Experience, Oxbow and Poor Boyz Productions team up again for this year’s film: Walls of Perception.
The new production presents 7 amazing riders (Matt Meola, Kai Lenny, Duane Desoto, Levi Siver, Jason Polakow, Antoine Delpero, Ian Alldredge) surfing different spots around the world (Maui, Oahu North Shore, Coco Islands ), before bringing them together in one unique place: the Marshall Islands.
The islands are a magic playground where everything becomes possible, where you can engage in all the various disciplines (shortboard, longboard, stand-up paddle, windsurf, kitesurf).

Shown from the riders’ perspective, the Oxbow team breaks down the stereotypical walls of the surf industry proving that there is no wrong way to ride a wave.
No matter which rider or sport, when you live life to the fullest there is only a fine line between your dreams and reality.

The riders of the Oxbow team bring us their unique spirit once again, with a production that’s really out of the ordinary and which reflects their authentic mindset.
Always looking for epic sessions and unique sensations, they invite us into their daily life, so that we can understand and share how they feel when they ride: their Walls of Perception.
“Look deep, deep into nature, then you will understand…”

Sailing fast on a Figaro - 35kts - rough weather

Jean-Pierre Nicol sailing around Porquerolles with 35 knots of wind.

>>> geolocalization with the Marine GeoGarage <<<< 

The french skipper Corentin Douguet sailed his Figaro Beneteau in 55 knots wind

Chasing ice: could time-lapse photography save the planet?

From Time

The Extreme Ice Survey, an artistic and scientific project founded by award-winning photographer James Balog, has 27 cameras pointed at 18 glaciers around the world.
Together, they snap 8,000 frames worth of time-lapse footage per year.
Thus the Extreme Ice Survey (EIS) is able to capture alterations to the arctic environment—changes that might seem to be slow, glacially so, are rendered dramatic.
Almost equally dramatic was the organization’s beginning, which is documented in a film called Chasing Ice, now screening at South by Southwest.

Rappelling into Survey Canyon, looking down at moulin channel dropping meltwater 2,000 vertical feet into crevasses through the Greenland Ice Sheet. EIS director James Balog is shown.

Between equipment unable to withstand the icy conditions and a faulty timer in an early camera, the project had a difficult start.
“I thought I was going to buy off-the-shelf parts and I was naïve about the hardware. I ended up designing custom stuff,” Balog says.
“We had a lot of money on the line, we had a lot of plans on the line, a lot of people on the line.”

It took months of trial and error, but their system of Nikon D200 DSLR cameras, solar panels, batteries, heavy-duty tripods, waterproof cases and wind-proof anchors is now reliable.
Some of the cameras are checked on and their images downloaded only once a year.

Balog’s initial attraction to the ice was one of aesthetics—“the sculpture, the beauty, the light, the form, the color,” he says—and a forthcoming photo book from EIS will showcase those facets of the glaciers.
But the technology innovated by Balog and his team doesn’t just allow EIS to take those pictures: the Survey aims to put them to good use.
Balog, who had been a skeptic about climate change until about 20 years ago, says that seeing the evidence of climate change may make a difference where human stubbornness otherwise persists.
He takes a zen perspective on change, believing that whatever landscape is underneath the glaciers, to be revealed by their melting, will also be perfect in its own way, but says he is disheartened by the extent to which people refuse to recognize their place in causing that change and its inevitable climatic, political and military consequences.

Photographer James Balog shares new image sequences from the Extreme Ice Survey, a network of time-lapse cameras recording glaciers receding at an alarming rate, some of the most vivid evidence yet of climate change.

“The deeper I got into it, the more I realized that our aesthetics were the pathway to communicate the science effectively, the knowledge base that the scientists had,” Balog says.
“The visual information can only be part of the puzzle but that’s the piece of the puzzle that I know how to put in the board.”

The footage from Chasing Ice dates back to the very beginning of the project.
At the time, Balog predicted he would want to have it on film but had no definite plans in mind.
It was not until 2009 that Jeff Orlowski, who had begun as an unpaid assistant cameraman for EIS, asked Balog for the rights to put the video to use.
The resulting film, directed by Orlowski, was given the Excellence in Cinematography Award at the 2012 Sundance Film Festival and has been acquired for TV broadcast by the National Geographic Channel.

Although Balog was not involved in the film’s production, he sees it as a part of the larger mission of EIS.
“I hope this becomes part of the wake-up call that will jostle people out of their intellectual hibernation,” he says, “and at the same time, if you stand back from all of that and you just look at the incredible beauty of what we’ve been shooting the past six years, it’s mind-boggling.”

Visualizing ocean shipping

100 years of ship paths in the seas :
This shows mostly Spanish, Dutch, and English routes--they are surprisingly constant over the period (although some empires drop in and out of the record), but the individual voyages are fun.
And there are some macro patterns--the move of British trade towards India, the effect of the American Revolution and the Napoleonic Wars, and so on.

 From SpatialAnalysis

I recently stumbled upon a fascinating dataset which contains digitised information from the log books of ships (mostly from Britain, France, Spain and The Netherlands) sailing between 1750 and 1850.

The creation of this dataset was completed as part of the Climatological Database for the World’s Oceans 1750-1850 (CLIWOC) project.
The routes are plotted from the lat/long positions derived from the ships’ logs.
I have played around with the original data a little to clean it up
(I removed routes where there was a gap of over 1000km between known points, and only mapped to the year 1800).
As you can see the British (above) and Spanish and Dutch (below) had very different trading priorities over this period.

What fascinates me most about these maps is the thousands (if not millions) of man hours required to create them.

 A looped visualization of all the voyages in the Climatological database for the world's oceans as if they occurred in the same year, to show seasonal patterns in ship movements and predominant shipping lanes from 1750 to 1850.

Today we churn out digital spatial information all the time without thinking, but for each set of coordinates contained in these maps a ship and her crew had to sail there and someone had to work out a location without GPS or reliable charts.

Contrast that with this map of cargo ships (bigger than 10,000 gross tonnage) during ONLY 2007 :

Routes, ports and betweenness centralities in the GCSN.

(a) The trajectories of all cargo ships bigger than 10 000 GT during 2007.

The colour scale indicates the number of journeys along each route.

Ships are assumed to travel along the shortest (geodesic) paths on water. 

(b) A map of the 50 ports of highest betweenness centrality and a ranked list of the 20 most central ports.

(from The complex network of global cargo ship movements)

Links :

• Zolnai blog : Cliwoc data

Cryosat mission's new views of polar ice

 

 This animation, generated using data from ESA's CryoSat satellite, shows changes in Arctic sea-ice thickness between October 2010 and March 2011.

Every year, the Arctic Ocean experiences the formation of vast amounts of floating ice during the winter months, and melting during the summer months.
(Note: due to the satellite's 92° inclination, a small area around the north pole is not observable)
credit: CPOM/UCL/ESA/Planetary Visions

From BBC

Europe's Cryosat mission is now watching the ebb and flow of Arctic sea ice with high precision.

The radar spacecraft was launched in 2010 to monitor changes in the thickness and shape of polar ice..Scientists have spent the past two years getting to grips with its data.
And on Tuesday, they reported that Cryosat was now delivering an unprecedented view of the seasonal growth and retreat of sea ice spanning the entire Arctic basin.
The researchers also released a map showing the difference in height across the Greenland ice sheet.

"The message is that Cryosat is working extremely well.
Its data are very reliable and the measurements we have match reality," said Prof Volker Liebig, the director of Earth Observation at the European Space Agency (Esa).
"We now have a very powerful tool to monitor the changes taking place at the poles," he told BBC News.
The Esa director delivered an update on the mission at London's Royal Society.
The information was also being released here at the European Geosciences Union (EGU) meeting in Vienna, Austria.

Several satellites have already detailed the recent and rapid erosion of summer sea ice extent as the Arctic has warmed.

But Cryosat's innovation has been to provide a means to get at a figure for ice volume - a far more significant number in terms of understanding the long-term viability of the ice.

To do this, the satellite carries one of the highest resolution synthetic aperture radars ever put in orbit.
The instrument sends down pulses of microwave energy which bounce off both the top of the ice and the water in the cracks, or leads, which separate the floes.
By measuring the difference in height between these two surfaces, scientists can, using a relatively simple calculation, work out the overall volume of the marine cover.

The Cryosat team, led from University College London, has spent the period since launch working through the satellite's measurements, validating and calibrating them against a number of independent observations.
These include data from plane-borne instruments, from direct on-the-ice assessments, and even from scientific sea-floor moorings that profile the ice floes as they pass overhead.
"We can now say with good confidence that Cryosat's maps of ice thickness are correct to within 10-20cm," said Dr Seymour Laxon, from UCL's Centre for Polar Observation and Modelling (CPOM).

Tuesday's release shows a complete seasonal cycle, from October 2010, when the Arctic Ocean was beginning to freeze up following the summer melt, right through to March 2011, when the sea ice was approaching peak thickness.
Cryosat found the volume (area multiplied by thickness) of sea ice in the central Arctic in March 2011 to have been 14,500 cubic kilometres.

This figure is very similar to that suggested by PIOMAS (Panarctic Ice Ocean Modeling and Assimilation System), an influential computer model that has been used to estimate Arctic sea ice volume, and which has been the basis for several predictions about when summer sea ice in the north might disappear completely.

In addition to the announcement on sea ice, the Cryosat team also published a digital elevation model (DEM) of Greenland.
The big island, too, has experienced some rapid changes of late and is losing tens of billions of tonnes of its ice cover to the ocean annually.
The DEM is a map of varying height, and the visualisation on this page incorporates a year's worth of data.

How to measure sea-ice thickness from space

Cryosat's radar has the resolution to see the Arctic's floes and leads
Some 7/8ths of the ice tends to sit below the waterline - the draft
The aim is to measure the freeboard - the ice part above the waterline
Knowing this 1/8th figure allows Cryosat to work out sea ice thickness
The thickness multiplied by the area of ice cover produces a volume

For Cryosat, it is another illustration of its capability.
Radar satellites have traditionally struggled to discern the detail in the steep slopes and ridges that mark the edges of ice sheets, but the Esa spacecraft can recover far more information thanks to a special interferometric observing mode that uses two antennas.

"This is really the first demonstration of the interferometer in action," said Prof Andrew Shepherd from Leeds University.
"The DEM contains about 7.5 million data points, and we're pretty confident this will be the best elevation model for Greenland, by some margin. Our next step is to compare it to previous data to see how Greenland has changed."

Cryosat's principal investigator, Prof Duncan Wingham - formerly of UCL but now chief executive of the UK's National Environment Research Council - summed up: "We have years of data to come, but I think it's quite clear that we will provide synoptic, accurate, Arctic-wide thickness; and that we will be able to determine the accuracy of the predictions of when the Arctic will be ice-free in Summer.

"And I think it's also clear we can now sustain coverage of [ice sheets on Antarctica and Greenland] right down to the coast."

The Cryosat update was timed to coincide with this week's 50th anniversary of UK activity in orbit.
April 1962 was the month Britain became a space-faring nation with the launch of its first satellite, Ariel-1.
As part of the celebration, current capabilities and missions with strong UK interest are being highlighted.