New International Cloud Atlas: 19th century tradition, 21st century technology

www.wmocloudatlas.org

From WMO

The World Meteorological Organization (WMO) has released its new, long-awaited, digitized International Cloud Atlas – the global reference for observing and identifying clouds, which are an essential part of weather, the climate system and the water cycle. It was released for the World Meteorological Day on 23rd March.

The new Atlas combines 19^th century traditions with 21^st century technology.
It contains hundreds of images submitted by meteorologists, photographers and cloud lovers from around the globe.
It includes new classifications, including volutus, a roll cloud; clouds from human activities such as the contrail, a vapour trail sometimes produced by airplanes; and asperitas, a dramatic undulated cloud which captured the public imagination.
It also features meteorological phenomena like rainbows, halos, snow devils and hailstones.

 Cloud classification

NOAA

“The International Cloud Atlas is the single most authoritative and comprehensive reference for identifying clouds. Its reputation is legendary among cloud enthusiasts and it serves as an essential training tool for professionals working in meteorological services, and in sectors such as aviation and shipping,” said WMO Secretary-General Petteri Taalas.
“Throughout the centuries, few natural phenomena have inspired as much scientific thought and artistic reflection as clouds,” said Mr Taalas.
“More than two millennia ago, Aristotle studied clouds and wrote a treatise addressing their role in the hydrological cycle. And today, scientists understand that clouds play a vital role in the Earth’s energy balance, climate and weather,” said Mr Taalas in a message for World Meteorological Day on 23 March.
“If we want to forecast weather we have to understand clouds. If we want to model the climate system we have to understand clouds. And if we want to predict the availability of water resources, we have to understand clouds,” said Mr Taalas.

Understanding Clouds is the theme of this year’s World Meteorological Day, which celebrates the anniversary of the convention establishing WMO in 1950 and showcases the essential contribution of National Meteorological and Hydrological Services to the safety and wellbeing of society.
The themes chosen for World Meteorological Day reflect topical weather, climate or water-related issues.
Understanding Clouds was chosen to coincide with the launch of the digital version of the International Cloud Atlas, after an exhaustive revision process and a public call for images from all over the world.

courtesy of the Cloud Appreciation Society (2009)

19^th Century Traditions

The International Cloud Atlas was first published in the late 19th century.
It contains a detailed manual of standards and numerous plates of photographs of clouds and certain other weather phenomena.
It was last updated in 1987 – before the Internet era.
For the first time, the 2017 edition will primarily be a web-based portal, allowing for much richer content and presentation. It may be published in hard copy at a later date.
“This is THE world reference for observing and classifying clouds and other weather phenomena. The Atlas contains pictures, definitions, and explanations that are accepted and used by all WMO’s 191 Member countries and territories,” said Bertrand Calpini, President of WMO’s Commission for Instruments and Methods of Observation (CIMO), which oversaw the revision process.
“This new edition brings together for the first time all types of measurements, including  very high-tech surface-based, in situ and space observations and remote sensing, thus giving to the human observer a revolutionary tool to understand clouds,” said Mr Calpini.
“The International Cloud Atlas task team had to choose from thousands of images from meteorologists, cloud lovers and photographers around the world,” said Chi-ming Shun, Director of the Hong Kong Observatory, which is hosting the web portal.
“We selected the best of the best.  We feel honoured to be involved in such a visible product of WMO. We applaud WMO for updating the International Cloud Atlas which provides a unique platform for engaging the public in better understanding clouds, weather and climate.”

The new classifications are available here

Classification of Clouds
The present international system of Latin-based cloud classification dates back to 1803, when amateur meteorologist Luke Howard wrote The Essay on the Modifications of Clouds.
There are ten basic cloud “genera,” which are defined according to where in the sky they form and their approximate appearance.
The new International Cloud Atlas has made no additions to these 10 genera.
High-level clouds typically have a base above about 5 000 metres (16 500 feet); middle-level clouds have a base that is usually between 2 000 and 7 000 m (6 500 to 23 000 feet); and low-level clouds usually have their base at a maximum of 2 000 m (6 500 feet).
Most cloud names contain Latin prefixes and suffixes which, when combined, give an indication of the cloud’s character. These include:

• Alto: mid-level (though Latin for high)
• Cirrus/cirro: feathers, wispy
• Cumulus/cumulo: heaped up/puffy
• Nimbus/nimbo: rain-bearing
• Stratus/strato: flat/layered and smooth

The 10 genera are subdivided into “species,” which describe shape and internal structure, and “varieties,” which describe the transparency and arrangement of the clouds. In total there are about 100 combinations.

Altocumulus volutus

The new International Cloud Atlas has added a new species: volutus or roll cloud (from the Latin volutus which means rolled), which occurs within the genera Altocumulus and Stratocumulus.
It describes a long, typically low, horizontal tube shaped cloud mass that often appeals to roll about a horizontal axis.
Five new supplementary features have been added: asperitas, cavum, cauda (often known as tail cloud), fluctus (widely known as Kelvin-Helmholz wave) and murus (known as wall cloud).
Best known of these is asperitas (from the Latin meaning roughness), Photographs of the dramatic, wave-like cloud captured the popular imagination around the world.
The Cloud Appreciation Society argued for a new classification to be used to describe clouds with this appearance.

 The wavy ridges of the rare asperitas cloud

The Atlas includes the winning photograph from a Cloud Appreciations Society competition on Asperitas.
“Asperitas was first identified with the help of citizen science, enabled by modern technology. When Cloud Appreciation Society members send us photographs of dramatic skies from around the world, it is possible to spot patterns. This is how the proposal for a new classification came about, and we are delighted the WMO has chosen to include it in their definitive reference work for cloud classification,” said Gavin Pretor-Pinney, founder of the Cloud Appreciation Society.

A new accessory cloud, flumen, has been included. Commonly known as “beaver’s tail,” it is associated with a supercell severe convective storm.
The International Cloud Atlas also proposes five new “special clouds:” cataractagenitus, flammagenitus, homogenitus, silvagenitus and homomutatus.
The suffix genitus indicates localized factors that led to cloud formation or growth, while mutatus is added when these caused the cloud to change from a different form.
These special clouds are influenced by large waterfalls, localized heat from wildfires, saturation of air above forests and humans.
Thus, a common example of homogenitus is contrails, sometimes seen after aircraft.
The World Meteorological Day ceremony will be webcast live to allow cloud enthusiasts around the world to have their first view of the new International Cloud Atlas and the new insight it provides into the beauty and power of nature.

Links :

• Eumetsat : WMO is revising the international cloud atlas
• BBC : 'New' wave-like cloud finally wins official recognition
• Mashable : There are 11 newly-classified clouds, and all of them are breathtaking 
• MNN : Say hello to the 11 new cloud atlas inductees 
• NASA : A Celebration of Clouds From Space, Earth Has an Elegant Atmosphere

Copulating seahorses and a lavish snail ballet: the underwater wonders of Jean Painlevé

From The Guardian by Hettie Judah

They may have infuriated the censor, but these beautiful films and photographs of cavorting creatures caused a sensation in the 30s.
As Ikon’s new exhibition shows, they have been overlooked for too long

 Desperately seeking the nose of a shrimp …

Jean Painlevé with his camera in a waterproof box, 1935

Photograph: Image courtesy of Archives Jean Painlevé, Paris

In the course of his lifetime, the aquatic French film-maker Jean Painlevé hung out with Man Ray and Alexander Calder, showed his work in galleries alongside the surrealists, and inspired George Balanchine to choreograph a lobster ballet.
His most successful film, 1934’s L’Hippocampe ou Cheval Marin, didn’t just incur the wrath of censors with its intimate footage of copulating seahorses.
It also provoked such a mania for the arresting little creatures that the Frenchman, somewhat improbably, launched a range of fashion accessories.
Overlooked for decades, Painlevé’s curious – and curiously beautiful – underwater movies have been championed by France’s current crop of global art stars, among them Pierre Huyghe and Philippe Parreno.
In recent years, his aquatic films have been seen in group exhibitions, becoming a point of reference for the art world’s mounting obsession with the animal kingdom.
Now Ikon in Birmingham is presenting his first British solo show.

A still from The Seahorse, 1931.

Photograph: Courtesy of Archives Jean Painleve, Paris 

It’s not often an exhibition is given its own bespoke wallpaper but, in keeping with the joy and playfulness of Painlevé’s underwater explorations, this show is something of a peculiarity itself.
The wallpaper, which enlivens the opening gallery, is a coral and seahorse design created by Painlevé’s partner Geneviève Hamon for a silk scarf.

The exhibition captures the range of Painlevé’s output in a career that stretched from the 1920s to the 70s.
On the walls hang intimate shots – the nose of a shrimp, the horn of a seahorse, the suckers of an octopus – all made with a microscope.
Taken in the 1920s and 30s, when Painlevé exhibited them blown up to monstrous dimensions, they are crisp, luminous and mysterious.

Of the four films shown, two are studies of aquatic creatures: the famous seahorses and the tiny Acera sea snails.
Both are oddly erotic in places. Painlevé allowed himself to be transported by his own delight in unexpected phenomena.
In the case of the Acera, these include hermaphroditic mating practices and a lavish, highly balletic dance, in which the snails use their tiny shells as ballast while they shoot themselves up and down in the water.
Painlevé sets this against music by Pierre Jansen – a composer best known for his work with Claude Chabrol – with each swoop echoed in the music, as though they were performing to a score for waltzing lovers.

Surreal sea … Crab Claw, 1928.

Photograph: Courtesy of Archives Jean Painlevé, Paris

While this may sound like something straight out of The Life Aquatic With Steve Zissou, Painlevé’s methods were rather more homespun than those of Wes Anderson’s titular hero.
In place of leopard sharks tracked in a minisub, the stars of Painlevé’s movies were tiny creatures – shrimp, squid, octopus, slug – caught by hand in shallow waters off the coast of Brittany.
Most of Painlevé’s films were made in aquariums in his studio laboratory, some double-walled to protect the inhabitants from the heat of the lights.
Beside the film-maker’s enthusiasm for his tiny subjects, what stands out is the use of cutting-edge and scientific equipment – underwater cameras and microscopy – that offered a new glimpse of this little-known world.
Of the other two films, one – a distinctly psychedelic study of the proliferation of liquid crystals – underscores Painlevé’s status as a scientist.
The other, which shows Alexander Calder operating a mechanical circus created in the 1920s, is a reminder of the film-maker’s close ties to the art world. Membership of the French Union of Communist Students in his younger days had also put Painlevé in touch with avant-garde film-makers including Luis Buñuel and Sergei Eisenstein, and he went on to speak and write extensively about his creative philosophies.

In 1948, he suggested Ten commandments of film-making, warning against the over-reliance on special effects and the use of monotonous sequences.
For all his associations with the avant-garde, Painlevé’s great ambition was that his films would reach the widest possible audience, spreading his enthusiasm and scientific knowledge.
They are, to this end, unapologetically entertaining, often highly anthropomorphic.
Watching the male seahorse eject hundreds of tiny babies from its pouch, Painlevé notes what seems to be alarm in the darting of its eyes, likening the whole experience to the contractions of human labour.
Part of L’hippocampe’s sensational success can be attributed to how its subjects upturned gender roles, something Painlevé clearly approved off, since one of his Commandments decrees: “You will refuse to direct a film if your convictions are not expressed.”
Narrating to some footage of female seahorses impregnating the male with eggs, Painlevé was emphatic in his approval, and no less enthusiastic about the subsequent division of labour in pregnancy and parenthood.
There’s some aquatic-themed costume jewellery on show in a glass vitrine here.
To the casual eye, it may seem a little out of place, but don’t be fooled.
That sea horse motif was a potent symbol of equality.

Links :

• The Guardian : The underwater world of Jean Painlevé in pictures

Oceans

Oceans

Mark Cunningham bodysurfing Tahiti.

Sea ice retreat could lead to rapid overfishing in the Arctic

From The Atlantic by Hannah Hoag

A consortium of countries are meeting in Iceland, where they hope to strike a deal that protects the newly accessible ecosystem.

The Arctic Ocean has long been the least accessible of the world’s major oceans.
But as climate change warms the Arctic twice as fast as anywhere else, the thick sea ice that once made it so forbidding is now beating a hasty retreat.
Since 1979, when scientists began using satellites to track changes in the Arctic sea-ice expanse, its average summertime volume has dropped 75 percent from 4,000 cubic miles to 1,000 cubic miles.
By September, the Arctic Ocean will have swapped nearly 4 million square miles of ice for open ocean.

This accelerated transformation has troubled scientists, conservationists and government officials who are anxious about the fate of the fish that may live in these waters—and for the entire ecosystem itself.
At the center of the Arctic Ocean is a 1.1 million square-mile “donut hole,” surrounded by Canada, the Danish territory of Greenland, Norway, Russia and the United States.
The donut hole does not fall under any country’s jurisdiction, and it may well be the last unexploited fishery on Earth.
According to international law, anyone could fish these newly opening high seas, if they desired, and thanks to the retreating ice, they may soon have their chance.

 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.

Image : Greenpeace

This week, delegations from the five Arctic coastal states and five of the world’s largest fishing jurisdictions are meeting in Reykjavík to hammer out a deal to prevent commercial fishing boats from casting their nets into the international waters of the Arctic until scientists complete a full assessment of its fish stocks.
“It’s my hope that we will actually bring this home, find some compromises on the key issues and produce an agreement that everyone can go ahead and sign,” says Ambassador David Balton, the deputy assistant secretary for Oceans and Fisheries at the U.S. Department of State, who is chairing the talks.

 Baffin Fisheries' MV Sivulliq

The agreement aims to avoid the tragedy that occurred in the Bering Sea in the 1980s.
At the time, the U.S. and the Soviet Union fished for pollock within their respective waters.
Almost no one believed there were fish—or foreign fleets—in the international waters between them, says David Benton, a retired fisheries manager from Alaska and a member of the U.S. Arctic Research Commission.

 Map of temperature anomalies from average during February 2017

credit NASA

A pair of Alaskan fishermen who thought otherwise chartered an airplane to fly over the donut hole and spotted close to 100 working vessels.
At its height, fishing fleets from Japan, China, Poland, South Korea and others were drawing more than a million of tons of pollock from the waters annually.
“It wasn’t illegal fishing because it was international waters,” says Benton, who is advising the U.S. delegation. But it was unregulated.

 A fishing boat cruises in the Ilulissat fjord, on Greenland's western coast.

An international treaty was quickly negotiated, but it was too late.
By the early 1990s, the pollock stock had collapsed.
Twenty-five years later it has still not recovered.

Compared with the donut hole in the Bering Sea, which clocks in close to 50,000 square miles, the one in the Arctic Ocean is enormous.
“There has been a lot of discussion about shipping in the Arctic Ocean, but in my experience the first people into an ocean are the fishermen,” says Peter Harrison, an Arctic policy and fisheries expert at Queen’s University in Canada, and a former deputy minister of Canada’s Department of Fisheries and Oceans.
Lately, as much as 42 percent of the central Arctic Ocean is open water during the summer months.

Links :

• The Guardian : Major fishing deal offers protection to Arctic waters
• Arctic : Federal Agency for Fishery: A new organization may be created to regulate Arctic fishing 
• ScienceDaily : Acidification of Arctic Ocean may threaten marine life, fishing industry 
• Scientific American : Arctic Sea Ice Sets Record-Low Peak for Third Year

Space view of Earth's magnetic rocks

After three years of collecting data, the highest resolution map of Earth’s lithospheric magnetic field from space to date has been released.

The dataset combines measurements from ESA’s Swarm satellites with historical data from the German CHAMP satellite using a new modelling technique that allowed scientists to extract tiny magnetic signals from Earth’s outer layer.

Red represents areas where the lithospheric magnetic field is positive, while blues show areas where it is negative.

From BBC by Jonathan Amos

It is the best depiction yet of the magnetism retained in Earth's rocks, as viewed from space.

The map was constructed using data from Europe’s current Swarm mission, combined with legacy information from a forerunner satellite called Champ.
Variations as small as 250km across are detectable.
Clearly seen are the "stripes" of magnetism moving away from mid-ocean ridges - the places on the planet where new crust is constantly produced.
This pattern - the consequence of periodic changes in Earth's polarity being locked into the minerals of cooling volcanic rock - was one of the key pieces of evidence for the theory of plate tectonics.
On land, the signal tends to reflect the composition and thickness of the different rock layers that make up the continents.
Generally speaking, younger crust will be thinner and have a low content in magnetic minerals. Whereas, the old cratons, those stable interior sections of continents, will tend to be thicker and have a higher magnetic mineral content.
Detecting any of this from orbit is a challenge because the signals are dwarfed by that part of the global magnetic field coming from the dynamo - the movement of liquid iron in the Earth's outer core.

 Artwork: The Swarm mission flies a trio of satellites above the Earth

(ESA)

Stand on the surface of the planet and the intensity of the global field may be between 25,000 and 65,000 nanoTeslas (a fridge magnet is a thousand times stronger).
"Again it depends where you are but the lithospheric signal is well below 100nT, even 50nT, on average," explained Nils Olsen from the Technical University of Denmark and one of the scientists who created the new space map.
"But we have certain regions where it can reach up to 2,000nT, and one of these regions is the Bangui anomaly in western Africa," he told BBC News.
This sharp signal in the Central African Republic is the possible impact site of a large iron asteroid more than 500 million years ago.

 The Bangui anomaly in western Africa may trace an asteroid impact 540 million years ago 

(ESA/DTU Space/DLR)

Another high intensity region in the crust is the famous Kursk anomaly in central Russia where substantial reserves of iron ore have been mined.
The German Champ spacecraft measured Earth's magnetic field from orbit between 2000 and 2010.
It was succeeded in 2013 by the Swarm trio of satellites operated by the European Space Agency (Esa).
Champ was lower in the sky than Swarm is currently, and so found it easier to detect the lithospheric magnetism. However, the sophistication of the new mission and the subtle differences the newer satellites can sense in side-by-side observations mean further detail still can be extracted from the data.
Champ alone was getting a resolution of 300-330km, so the combined model is a big step forward.

 The new space information will be fed into future versions of the WDMAM 

(J.KORHONEN ET AL)

Our very best global view of crustal magnetism is the World Digital Magnetic Anomaly Map (WDMAM), which was put together by scientists over many years, and includes much high-resolution aero- and ship-borne measurements.
But the WDMAM would be very patchy if it did not also include space data, said Mike Purucker from the US space agency.
"The World Digital Magnetic Anomaly Map is a 5km grid at 5km altitude around the world. The longwave component is provided by satellite observations and the shorter wavelengths by aero and marine surveys.
"[The satellite data] defines better the magnetic field under the auroral ovals where it has been very difficult to separate internal from external fields," he told the BBC.
Future versions of the WDMAM will now make use of the updated Champ/Swarm view.
Having maps of crustal magnetism is important for investigating the geological history of Earth and for understanding the distribution of commercially important mineral resources, says Kathy Whaler from Edinburgh University, UK.
"[The new Swarm/Champ] model should mean estimates to the depth at which magnetisation is lost are better.
"Our assumption is this is where the temperature reaches the Curie point. There has previously been a suggestion that this is deeper in some subduction regions, as well as possibly over old, thick, stable cratons, for example.
"We should be able to estimate these depths as a function of position on the surface more accurately, and thereby understand some of the large-scale tectonics better."

The magnetic stripes associated with seafloor spreading underpin plate tectonics theory 

(Image copyright ESA/DTU Space/DLR Image caption)

Swarm itself is trying to provide greater insights on all of the different contributors to the global magnetic field.
As well as the rocks and that dominant signal coming from the swirling convection of molten iron in the core, there are other inputs pulling on the needle of every compass.
These include the magnetism generated by electric fields high above the Earth, and even a very subtle effect derived from the movement of salt water ocean currents.

 Image caption Earth's magnetic field acts as shield to deflect potentially damaging particles coming from the Sun

(Image copyright SPL)
 

Long-term observations will tease apart the size of each contribution and how it varies through time.
"The Bravo satellite is still at slightly above 500km and the Alpha and Charlie satellites are at 443km, roughly. So we are still at a good altitude,” said Esa's Swarm mission manager, Rune Floberghagen.
“Considering the fuel situation, we are set for a very, very long mission - far beyond the upcoming solar minimum and following solar maximum, and perhaps even up to the solar minimum after that."
This would mean at least one Swarm satellite still working in 2031.

This animation shows changes in Earth's magnetic field from January to June 2014

as measured by ESA's Swarm trio of satellites.

It is a fascinating prospect because one key to understanding Earth's magnetic field is seeing how it interacts with the magnetic fields and particle matter emanating from the Sun over its 11-year cycle of activity.

The new lithospheric magnetic field map was presented on Tuesday at an Esa Swarm science meeting in Banff, Canada.

Links :

• GeoGarage blog : Magnetic oceans and electric Earth / Magnetic anomalies of the world's largest volcano / Earth's magnetic declination / Earth's magnetic field : lesson from ESA / World Magnetic Model updated / Dynamic Earth / Earth's magnetic field shifts / Earth's core, magnetic field changing fast, study says