Saturday, October 19, 2019

Home review – gutsy doc charts harrowing, heroic journey by sea

Like Cheryl Strayed in Wild, Sarah Outen bravely explores mental health issues and grief as she chronicles her four-year round-the-world adventure

From The Guardian by Cat Clarke

The British adventurer Sarah Outen has made an introspective and emotionally brave film about her awe-inspiring journey around the world.
She travelled 20,000 miles in four years, powered entirely by her own steam – on bike, foot and rowing boat.
Documentaries about big adventures usually feature a scene or two in which the hero (usually male), with chest-beating bravado, goes mano a mano with nature.
Not here.
In Alaska, Outen giggles when a bear sneaks up on her having a wash.
And it takes real guts to open up as she does about mental health issues in her elegant, self-aware voiceover.

Her adventure begins in 2011 rowing across the Channel to France, and from there it’s five and half months on the bike.
A recent Oxford graduate, Outen describes herself as confident and accomplished, but feeling lost and grieving the death of her father.
In Kazakhstan, she falls for the landscape and the hospitality.
People constantly invite her in for tea and ask: “Where is your husband?”
She points to her bike, Hercules.
Make no mistake, Outen is a tough lady, but her warmth and gentleness are as helpful while travelling so far alone.
In China, she picks up a young lad, Gau, who has recently dropped out of business school – and for 2,000 miles to Beijing the film becomes a buddy comedy.

Her adventure doesn’t go entirely to plan; a tropical storm at sea wrecks her boat and causes lasting emotional and physical harm.
While recovering in the UK, Outen falls in love and asks herself what’s the point of going back to finish.
Her film – co-directed with Jen Randall – shares with Cheryl Strayed’s memoir Wild a sense of the redemptive and healing power of travel.
Outen also has the nerve to probe her motives: what is she running from and why is she always restlessly planning journeys?
And she calls her boat Happy Socks, which is the most pleasing boat name since Boaty McBoatface.

Friday, October 18, 2019

Old weather “time machine” opens a treasure trove for researchers


One key to the past is crowd-sourcing data recovery

It’s been the stuff of science fiction for generations: a time machine that would allow researchers to reach back into yesteryear and ask new questions about long-ago events.

This month, a NOAA-funded research team published an update to a weather “time machine” they’ve been developing since 2011.
This third version of the 20th Century Reanalysis Project, or 20CRv3 for short, is a dauntingly complex, high-resolution, four-dimensional reconstruction of the global climate that estimates what the weather was for every day back to 1836.

The newest update provides continuous estimates of the most likely state of the global atmosphere’s weather on 75-kilometer grids eight times a day for the past 180 years.
It’s the scientific fruit of an international effort led by researchers with NOAA's Physical Sciences Division (PSD) and CIRES and supported by the Department of Energy.

 This painting by James Gale Tyler depicts the crew of the USS Jeanette abandoning ship in 1881 after more than a year trapped in Arctic ice.
Barometric pressure observations from the ship's log comprise some of the data used to reconstruct global weather in the updated 20th Century Reanalysis dataset released by NOAA on Oct 9, 2019. Source: Wikipedia

The research opportunities that this work makes available are almost boundless, said Gil Compo, a CIRES scientist working at NOAA who leads the reanalysis project.
“We’re throwing open the door to lost history, and inviting scientists to pour through,” Compo said.
Old weather records fed into modern weather model

Using NOAA’s Global Forecast System, researchers reconstructed the global atmosphere from surface pressure readings, sea temperature and sea ice observations from archival records, some transcribed by citizen volunteers.
From this data, the model estimates temperature, pressure, winds, moisture, solar radiation and clouds.

 This U.S. Weather Bureau Map depicts northern hemisphere circulation patterns on Aug. 16, 1915, as the Galveston hurricane made landfall on the Texas coast.
Surface pressure observations from historic weather records like this allow scientists to reconstruct global weather using modern weather models.
Credit: NOAA Physical Sciences Division

Scientists have used previous 20th Century Reanalysis datasets as a foundation for a wide range of studies, from understanding large-scale climate trends to diagnosing the impacts of individual historical extreme weather events.
The dataset allows researchers to explore how climate change is influencing temperature, precipitation, and atmospheric circulation, and compare today’s storms, heat waves, droughts and floods to historic events.
“This tool lets us quantitatively compare today’s storms, floods, blizzards, heat waves and droughts to those of the past and figure out whether or not climate change is having an effect,” Compo said.
“This should be useful for climate attribution research.”

Enriching our understanding of long-ago events

Scientists have also used the previous versions of the “old weather” data to discover unknown hurricanes, study the climate impact of old volcanic eruptions, investigate the timing of bird migrations, and even explore the economic impact of diseases spread by the tsetse fly in sub-Saharan Africa.

Colorado State University hurricane researcher Phil Klotzbach said he can’t wait to begin working with 20CRv3.
“I’m a huge fan of reanalysis products,” said Klotzbach.
“I’ll probably be diving in by next week and I know my colleagues are looking forward to working with it.”

Others have used the data to enrich the scientific understanding of specific weather lodged in cultural memory, like the sinking of the Titanic or the extraordinary winter of 1880-1881, which was chronicled by Laura Ingalls Wilder in her book “The Long Winter.”

“I’ve found reanalysis composites incredibly useful and accessible,” said Barbara Mayes Boustead, a meteorologist instructor with NOAA’s National Weather Service, who has studied the winter of 1880-1881.
“We introduce them in our course on operational climate services and to weather forecast offices who want to investigate climate events like the El Niño-Southern Oscillation.”

A big appetite for big data

20CRv3 uses millions more observations than previous versions of the reanalysis, especially for earlier periods.
The new reanalysis includes up to 25 percent more available observations for years prior to 1930.
Running the model and crunching all this data required astronomical computing resources.
To accomplish this third upgrade, the Department of Energy donated 600 million cpu hours to crunch 21 million gigabytes of data at the National Energy Research Scientific Computing Center.

The result?
This new update provides a much better indication of where the weather estimates are more reliable, and where more observations are needed.
“The atmospheric estimates from 20CRv3, as well as their uncertainties, are much more reliable than those from the previous reanalysis, particularly in the 19th century,” said Laura Slivinski, a CIRES meteorologist and the lead author of a recent paper in the Quarterly Journal of the Royal Meteorological Society that lays out improvements in their reanalysis techniques.
“We’re more certain about how much we know, and where we need to know more.”
Citizen scientists help chart a “virtuous circle” of discovery

Some of the key players in the reanalysis story are groups like Atmospheric Circulation Reconstructions over the Earth, which marshals professional scientists and ordinary citizens alike to pore over historical documents like ship logs and extract meteorological observations that are used to refine old weather reconstructions.
Targeted data rescue can be extraordinarily valuable - for example, logs of 19th Century wooden sailing vessels attempting to penetrate the Arctic and Antarctic.

“These data have been invaluable to us because they come from the otherwise data-sparse polar regions,” Slivinski said.
“20CRv3 also provides a literal map to further advances in precision by identifying regions and time periods where additional weather observations will improve model estimates,” she added.

Earlier time periods, especially in the Southern hemisphere, still have high uncertainty.
Luckily, data rescue can help fix that.
“This dataset can keep getting better as we unlock more observations from historical archives,” Compo said.
“It’s really a virtuous circle.”

Links :

Thursday, October 17, 2019

Unmanned ship to go on 400-year-old journey across the Atlantic

 The Mayflower Autonomous Ship will set sail in September 2020, 400 years after the first Mayflower, and this time AI and other advanced technologies will be at the helm.

From BBC by Jen Coperstake

A fully autonomous ship tracing the journey of the Mayflower is being built by a UK-based team, with help from tech firm IBM.

The Mayflower Autonomous Ship, or MAS, will launch from Plymouth in the UK in September 2020.

The Mayflower Autonomous Ship : max speed 20 knts, length 15 m, weight 5 tons

Its voyage will mark the 400th anniversary of the pilgrim ship which brought European settlers to America in 1620.

IBM is providing artificial intelligence systems for the ship.

 Timeline :
October 2019 - January 2020: Hull constructed in Gdansk, Poland
February 2020: Hull to arrive in Plymouth, UK
February - June 2020: Fitted out with advanced navigation and research equipment
July - August 2020: Testing at sea
September 2020: Sets off from Plymouth, UK, to arrive in Plymouth, Massachusetts, USA, two weeks later

The vessel will make its own decisions on its course and collision avoidance, and will even make expensive satellite phone calls back to base if it deems it necessary.
  • The sensor technology guiding its decision-making process includes:
  • Light detecting and ranging (LIDAR)
  • Radio detecting and ranging (RADAR)
  • Global Positioning System (GPS)
  • Satellites
  • Cameras
Data on hundreds of ships has already been collected in Plymouth Sound to feed its machine-learning algorithms.

Pilgrim journey

400 years ago, on 6 September 1620, the Mayflower set sail from Plymouth to Massachusetts, with 102 passengers and around 30 crew members.

The original journey took more than two months, landing at what is now Plymouth, Massachusetts, on 21 December 1620.
The passengers onboard, mainly Christian Puritans, became known as pilgrims.

A comparison of the original Mayflower with its futuristic version

This vessel will repeat their journey but without any humans on board, and a much faster anticipated crossing time of two weeks.

The ship is being built by ProMare - a non-profit marine research organisation - along with IBM.

The project's director, Brett Phaneuf, has ancestral roots in the area where the Mayflower landed on America's east coast, dating back to 1628.
Mr Phaneuf grew up in New England hearing family folklore about the early settlers, and visiting sites connected to the crossing.
He now lives in Plymouth, UK, and was inspired by his history to contribute to the commemorations of the 400th anniversary of the Mayflower.
But he wasn't interested in building a simple replica of the ship.
"Nothing really was going to do it justice," Mr Phaneuf says.
"My immediate interest is in autonomy and we needed something that would speak to the next 400 years."

Sleek design

The ship is a trimaran with one very long slender main hull optimized for propulsive efficiency.
The two smaller hulls are for stabilization and provide the surface area for the solar panels.
The vessel will run on solar and wind power, with an emergency diesel backup generator if needed.
The hull of the ship is currently under construction in Gdansk, Poland, and is due to arrive in Plymouth next February.

Virtual reality experience of the new Mayflower autonomous ship next to the original in Plymouth Port (University of Birmingham)

"On a ship with no people there is a huge amount of volume left to do things with - there's nowhere for people to sleep, no need for storing food or water - all the things that keep people alive go away," says Mr Phaneuf.

Mr Phaneuf says many ships already have highly automated systems, but keep skeleton crews of 6-12 people.
"The ship is going to do oceanographic research but it is also an active test platform for artificial intelligence and machine-learning algorithms for collision avoidance," he says.
The team will keep an eye on its progress from a control centre in Plymouth and can take over if there is an emergency.
"Once it's past the Isles of Scilly, it's on its own," says Mr Phaneuf.

Data collection

IBM's deep learning software will help the vessel collect and analyse data to avoid collisions at sea, according to the company's chief technology officer Dr Andy Stanford-Clark.
"We are fusing all that data to create a multi-dimensional view of the world," he says.
"The ship can't keep going back to the cloud and saying 'can you check on this' as there will be long periods of time where there is no connectivity," says Dr Stanford-Clark.

The ship will use IBM's sophisticated operational decision maker (ODM) tool, which is also used by the financial industry to produce billions of complex functions.

Artist's rendition of the Mayflower Autonomous Ship showing room for science pods

Different views of the ship's design showing solar panel placement


Three research pods in the hull of the ship are being designed by scientists at the UK's University of Plymouth.
Director of the University's Marine Institute, Richard Thomson OBE, says the voyage is the first opportunity to sample the oceans for plastics, from an unmanned vessel.
Professor Thomson coined the term microplastics in a paper published 15 years ago, to describe the accumulation of fragments of plastic in the world's oceans.
'We're trying to construct a heat map of the problem but it is based on pinpoint sampling and extrapolation," he says.
"This is an opportunity to get a much deeper and data-rich picture of the situation."

image Promare

The ship's ability to make its own decisions based on immediate data availability could lead researchers to remote areas where they wouldn't otherwise think to go.
"In the future, ten years from now, if the boat is in the middle of the deep Indian Ocean, and it detects something unusual but its humans want it to do something else, it can divert itself, as it will be seeing more data and say 'this is where I want to go'," says Mr Phaneuf.

The team inside the Mayflower Autonomous Ship mission simulation room


A future of autonomous vessels roaming across the world's oceans brings up several issues around insurance, cyber-security and piracy.

Mr Phaneuf says this first voyage is being insured by insurance company Gard, which wanted to be the first company to insure an unmanned ocean vessel.

The main threat in the North Atlantic, he says, will come from the weather and the ocean conditions, rather than other vessels.
But not knowing what the ship will find is an exciting prospect.
"We know more about the surface of the moon than the surface of the ocean.
This is the first of many ships that will bring us to that state of knowledge," Mr Phaneuf says.

Links :

Wednesday, October 16, 2019

Greenland's melting ice may affect everyone's future

Icebergs in Disko Bay, Greenland.
Photograph by Michael Melford, National Geo Image collection

From National Geographic by Alejandra Borunda

NASA scientists are trying to understand how this region is responding to climate change—and how that will influence sea levels around the world.

A thousand feet above the glistening, iceberg-dotted water of the ocean off of East Greenland, oceanographer Josh Willis braces for balance, his feet spread wide on the metal floor of a specially-outfitted airplane.
He grips a wide grey cylinder, hovering it over a 6-inch-wide bottomless tube.
The pilot’s voice crackles over the intercom: “3, 2, 1, zero, DROP.”
Willis lets the cylinder go.
With a whoosh, it slips down the tube and into the wide-open air.

The plane banks hard to the right and everyone on board rushes to a window.
“I see it!” yells Ian Fenty, another oceanographer on the project, as the probe—designed to sink to the seafloor and record the properties there—splashes down.

Willis, Fenty, and a crew of other scientists and pilots are flying the edge of Greenland’s vast ice sheet to figure out how the ocean eats away at the ice, speeding or slowing its slide into the water, where it melts, raising sea levels worldwide.

In an airplane flying low over the eastern coast of Greenland, Josh Willis, the lead scientist for the Oceans Melting Greenland (OMG) research project, prepares to drop a probe through a chute in the floor of a retrofitted DC-3 plane.
The probe will fly through through the air and land in the coastal ocean, where it will measure the temperature and salinity of the water.
photograph : Jonathan Nackstrand, AFP/Getty Images

But exactly how much ice it will deposit, and how fast, is still an open question.
Greenland is currently the biggest contributor to global sea level rise.
By 2100, will its ice sheet’s melt add inches to the world’s oceans—or will it add much more?

That’s a trillion-dollar question.
Nearly 70 percent of Earth’s population lives within 100 miles of a coast, and vast amounts of infrastructure—from airports to ports to cities to roads to Internet cables—sits in zones that could flood within decades.
Small, low-lying island nations, city planners, insurance adjustors, homeowners—everyone is clamoring for the most accurate estimates of how much extra water they’ll need to prepare for.

And for that, says Willis, they need to know what happens here, where ocean meets ice.
“This is where it all happens,” he says. The flooding of the future is being defined here and now, in the glittering sea below.

A sudden lurch into melting

Greenland’s ice is shrinking, this we've known for a while, since the science of global warming, a famous climate scientist likes to say, is older than the technology that makes our iPhones fast and the Internet run smoothly.

But until the 1990s, the ice in Greenland was remarkably stable, even as air temperatures rose because of human-caused climate change.
Each year, the ice sheet lost some weight as ice flowed like taffy from the center of the ice sheet, through funnel-like outlet glaciers at its edge, spilling into the ocean.
But enough snow fell on top of the mile-high interior of the ice sheet to balance out the losses.

In the 1990s, scientists thought that the big ice sheets in Greenland and Antarctica responded slowly to changes in climate, shuddering into motion like bears waking up from hibernation.
Yes, they’d respond to the human-caused climate change that was gripping the planet, the thinking went, but it would take decades or even centuries to really see the impacts.
“Early on, we weren’t thinking about Greenland as being really critical on these kind of decadal scales, and we didn’t have tools to look at them on those time scales,” explains Twila Moon, a glacier expert at the National Snow and Ice Data Center.

NASA's Oceans Melting Greenland (OMG) mission uses ships and planes to measure how ocean temperatures affect Greenland's vast icy expanses.
Jakobshavn Glacier, known in Greenlandic as Sermeq Kujalle, on Greenland's central western side, has been one of the island's largest contributor's to sea level rise, losing mass at an accelerating rate. In a new study, the OMG team found that between 2016 and 2017, Jakobshavn Glacier grew slightly and the rate of mass loss slowed down.
They traced the causes of this thickening to a temporary cooling of ocean temperatures in the region.

But around 1997, something changed.
Scientists studying Jakobshavn glacier, on Greenland’s western coast, watched in alarm as a tongue of ice that had for years poked out into a fjord started to shrink.
The tongue was about 15 kilometers long in 1997.
By the early 2000s—a scant half decade later—that tongue was gone.
“We suspected that this could happen from time to time, but this was the first time we’d seen anything like it,” says David Holland, who led the team studying the rapid disintegration of the ice tongue.

Huge chunks of ice break off the Jakobshavn glacier in Western Greenland.
Photo by James Balog, Nat Geo Image collection

Today, the Greenland ice sheet is losing mass about six times faster than it was just a few decades ago, whatever tenuous balance that existed before long since upended.
Between 2005 and 2016, melt from the ice sheet was the single largest contributor to sea level rise worldwide, though Antarctica may overtake it soon.

Within the past 50 years, the ice sheet has already shed enough to add about half an inch of water to the world’s oceans, and that number is increasing precipitously as the planet heats.
During this summer’s extreme heat wave that parked over Greenland for a week and turned over half its surface ice to slush, meltwater equivalent to over 4 million swimming pools sloughed into the ocean in a single day.
Over the month of July, enough melt poured into the ocean to bump sea levels up by an easily measurable half a millimeter.

Scientists at the University of Alaska Fairbanks’ Geophysical Institute used data from NASA’s Operation IceBridge to develop a more accurate model of how the Greenland Ice Sheet might respond to climate change in the future, finding that it could generate more sea level rise than previously thought.

Overall, there’s enough water locked up in the Greenland ice sheet to add about 25 feet to the world’s oceans.
It’s not likely that such catastrophic loss will happen soon, as in within the next few hundred years. But the whole of the ice sheet doesn’t have to collapse to cause massive, planet-wide reverberations.
“When I started this research, I never would have guessed that warm subsurface waters could unravel an ice sheet,” says David Holland, an oceanographer at NYU.
“But it’s becoming clear that they can, and that they are.”

Links :

Tuesday, October 15, 2019

Ocean exploration changed human History—and the story started centuries before Christopher Columbus

Illustration of the Nina, Pinta and Santa Maria, the fleet of Christopher Columbus.
Bettmann/Getty Images

From Time by David Abulafia author of The Boundless Sea: A Human History of the Oceans
(with additional content from WP by Max Fisher)

One of humanity’s greatest achievements has been mastering routes across the world’s oceans.
Communities separated by thousands of miles have been brought into contact and religious ideas have spread across the waters, while artistic creativity has been spurred on by the experience of seeing the products of different civilizations.
Customs have been decisively altered by the movement of ships across the oceans.
No one drank tea in medieval Europe, but once contact had been made with the tea-drinking Chinese, tea became the obsession of millions of people from Sweden to the United States — tea is part of the founding history of the United States, as the Boston Tea Party reveals.

We tend to think that the opening of the oceans was the work of the great explorers, especially the 15th century pioneers who edged their way through uncharted waters to southern Africa, the Indian Ocean and the spice lands of the Indies.
These were sailors such as Christopher Columbus, who chanced upon unsuspected lands that blocked the expected sea route from Europe to China and Japan.
But while these men did give the Age of Discovery its name, they didn’t start the exploration of the world’s oceans — and there were also scores of merchants who followed in their wake, taking full advantage of new knowledge about the open ocean to develop trade links across the world that were the precursors of modern globalization.
These were the people who really mastered the oceans and brought the continents into contact.

Already around 2500 BC, merchants were setting out from what is now Iraq, the seat of the ancient Sumerian civilization, carrying silver ingots to India, which was the seat of another even more mysterious civilization, that of the Indus Valley.
En route, they acquired copper from Oman and brought precious objects such as carnelian and lapis lazuli from India.
Accumulating and re-investing profits, they were the first capitalists.
The Indian Ocean became one of the great channels of trade between nations.
Greek merchants from Egypt exploited the monsoon winds to ensure a swift passage to south India.

The Chinese emperors tended to discourage uncontrolled trade, though prohibitions often did more to provoke traders into finding ways around the rules.
Early compasses were used for feng shui, not navigation.
But in the 12th century AD, when the coasts of China were open to the world, Hangzhou was at the peak of its prosperity.
Later, Marco Polo would bear witness to this vigorous commercial life, with its use of paper money and its links to Java and beyond.
And in the open Pacific, hundreds of scattered islands from Hawaii to Easter Island were settled over many centuries — the Polynesians only reached New Zealand around AD 1300.
Even without written records, the Polynesians transmitted exact knowledge of how to sail these apparently boundless waters from generation to generation.

By 1500 AD, the Portuguese had begun to show interest in what the Atlantic might offer.
That interest had resulted in the settlement of uninhabited islands including Madeira, which began to export phenomenal quantities of sugar.
Portugal also founded the slave trade, bringing captives from West Africa to Europe and later to the Americas without consideration for their humanity

 When Spain and Portugal dominated the world
This map shows the Spanish and Portuguese empires at their height.
They didn't hold all of this territory concurrently, but they were most powerful from 1580 to 1640, when they were politically unified.
Portugal would later pick up more territory in Africa, not shown on the map.
We often forget that Spain controlled big parts of Europe, in Italy and the Netherlands.
In the Middle Ages, Spain and Portugal were so powerful that they signed a set of treaties literally dividing up the globe between them.
They became so rich so quickly that their trade with the Ottoman Empire, perhaps the other great imperial power of the time, filled the Ottoman economy with more gold than it could handle and plunged it economy into an inflationary crisis so severe that the empire never fully recovered.

When European sailors — from Portugal, Spain, Holland, England, Denmark and France — entered the Pacific and the Indian Ocean starting in the 16th century, they found a lively maritime world that they could never truly dominate.
They still depended on the resources and supply lines of the inhabitants of the lands they visited, even as they created routes across the entire globe that brought Chinese porcelain and silk from Manila through Mexico to Havana and then on to Spain, or through Macao and then on past southern Africa all the way to Europe.
A symbol of these global links was the porcelain produced in China bearing the words E PLURIBUS UNUM made specially for the American market.

Major shipping routes in the colonial era
This map shows British, Dutch and Spanish shipping routes from 1750 to 1800.
It's been created from newly digitized logbooks of European ships during this period.
(Unfortunately, the French data is not shown.)
These lines are the contours of empire and of European colonialism, yes, but they're also the first intimations of the global trade and transportation system that are still with us today.
This was the flattening of the world, for better and for worse.
source : CLIWOC , image James Cheshire

Since then, the oceans have only continued to tie the world together — most dramatically when new routes were literally carved out, with the building of the Suez Canal in the 19th century and the opening of the Panama Canal in 1914.
The first goods to pass through the Panama Canal consisted of a cargo of tinned pineapples from Hawaii.
The Pacific and the Atlantic were more closely tied together than ever before.

 Americans have mostly come around to accept that, despite what our grade school teachers may have told us, Europeans did not "discover" America; the original arrivals had done that 15,000 years earlier.
But Europeans did discover lots of land that had never been before seen by human eyes.
You can, embedded in this map, see successive waves of European exploration: first the Portuguese, then the Spanish, then the British and much later the Americans.
The map's creator, the always-insightful Bill Rankin, writes, "this map particularly underscores the maritime expertise of Pacific Islanders.
Unlike the islands of the Atlantic and Indian Oceans, nearly all of the Pacific was settled by the 14th century."

In the 21st century, however, new factors have changed entirely the way goods are carried across the seas, even though over 90% of world trade is carried on ships.
Containerization means that goods can be loaded in Chicago and unloaded in Warsaw without having to be unloaded at ports.
The great port cities of the world have been replaced by automated docks full of gantries and cranes.
Container ships carry many thousands of containers.

Map lets you visualize shipping traffic around the world
Interactive data visualization illustrates the incredible number of ships criss-crossing the world's oceans at any given time
source :

Business is conducted on a scale that utterly dwarfs that of even 20 years ago, transforming a familiar world.
And yet, through trade and cultural exchange, the seas continue to connect even the most distant lands.

Links :

Monday, October 14, 2019

Typhoon, Cyclone or Hurricane? Different names for the same storms

Typhoon Hagibis approaching the southeast coast of Japan on last Wednesday. Typhoon Hagibis made landfall in Japan on Saturday, bringing violent winds, record rainfall and flooding.
Credit : NASA

From NYTimes by Mariel Padilla and Jennifer Jett

Powerful tropical storms occur all around the world, but what they’re called depends on where they form.

When a tropical storm pummeled Japan on Saturday with gusts of up to 135 miles per hour, forcing millions to evacuate their homes, it was called Typhoon Hagibis.
But the storm that carved a path of destruction across the Bahamas in September was Hurricane Dorian.
And when the most powerful storm to hit Bangladesh in years destroyed thousands of homes in May, it was called Cyclone Fani.

Surging waves in Kiho, Japan, on Friday.
credit : Toru Hanai/Associated Press

What is the difference between a typhoon, a hurricane and a cyclone?
It comes down only to the storm’s location.

All three are tropical cyclones — circular storms that form over warm waters with very low air pressure at the center, and winds greater than 74 miles an hour.
But different terms are used for such storms in different parts of the world.

The word “hurricane” is used for the storms that form in the North Atlantic, the northeastern Pacific, the Caribbean Sea or the Gulf of Mexico.
Typhoons develop in the northwestern Pacific and usually threaten Asia.

 The Century’s strongest super-typhoon Hagibis hitted Japan.
image : ISS

The international date line serves as the Pacific Ocean’s dividing marker, so when a hurricane crosses it from east to west, it becomes a typhoon instead, and vice versa.

The same kinds of storms in the Southern Hemisphere are easier to keep straight.

In the southern Indian Ocean or the South Pacific, they are called tropical cyclones or severe tropical cyclones.
In the Bay of Bengal or Arabian Sea, both in the northern Indian Ocean, they are simply called cyclones.

 The rising Isuzu River in Ise, Japan, on Saturday.
Credit Kyodo News, via Associated Press

A season for every storm

In addition to having different names, hurricanes, typhoons and cyclones also have different seasons.
The Atlantic hurricane season officially runs from June 1 to Nov. 30.
The Pacific season starts slightly earlier.
Typhoons can form year round, but are most common from May to October.
The next cyclone season in the South Pacific will begin on Nov. 1 and end on April 30, 2020.

In the southern Indian Ocean, the season begins two weeks later and ends at the same time, except in the island nations of Mauritius and the Seychelles, where it extends to May 15.
Cyclones in the northern Indian Ocean have no official season, but tend to be concentrated from May to November.

What are hurricanes, typhoons and tropical cyclones and how do they form?
James Chubb at MetOffice explains how we classify the different storms and how they are formed.

Whatever they are called, tropical cyclones generally become weaker after they hit land, since they draw their energy from water evaporating from the oceans below them.
But they can travel quite far inland before they dissipate, wreaking havoc through wind damage, torrential rains and flooding.

Storms whose winds are not quite strong enough to qualify as tropical cyclones are called tropical storms if their sustained winds are 39 to 73 miles an hour, or tropical depressions (a reference to the low pressure at their core) below that range.

Tropical cyclones around the world are named according to a listmaintained by the World Meteorological Organization.
The names of the deadliest storms, like Typhoon Haiyan or Hurricane Katrina, are retired.

 Typhoon Hagibis

Grading a storm’s intensity

Hurricanes are rated in categories from 1 to 5 on the Saffir-Simpson scale, which is based on sustained wind speed.
According to the National Hurricane Center, storms in Category 3 or higher, which have wind speeds of at least 111 miles per hour, “are considered major hurricanes because of their potential for significant loss of life and damage.”

 Super Typhoon Hagibis. 
Earth's power & beauty on display.

Typhoons are monitored by the Japan Meteorological Agency, which also rates them by sustained wind speed.
It uses three classifications: “typhoon,” “very strong typhoon” or “violent typhoon.”

Powerful Typhoon Hagibis brings strong waves to the southern tip of Japan's Izu Peninsula.
It is forecast to crash into land in central or eastern Japan early Saturday evening, packing maximum gusts of 216 kilometres per hour (134 miles per hour), Japan's Meteorological Agency (JMA) said.

The super Typhoon Hagibis, now approaching Japan, is the 4th category 5 storm of 2019.
In the Pacific there was Typhoon Wutip, while in the Atlantic there was hurricane Dorian and Lorenzo.
The above animation shows the movement of Typhoon Hagibis using the Copernicus Marine Service product “Global Ocean Waves Analysis and Forecast updated Daily” significant wave height (in meters) from October 8th-14th, 2019.
Our forecast up to October 14th predicts up to 15 metre significant wave heights starting around October 10th, and these wave trains are expected to hit the southwestern coast of Japan on the 12th of October.
The significant wave height is the average height of the highest one-third of all waves. Hence, maximum wave height could be 1.5 to 2 times higher.
According to the Meteo France waves model team, that works on this Copernicus Marine Service product, wave height is generally predicted with good confidence for extreme weather events within wave models.
 source : Copernicus

The Joint Typhoon Warning Center, a United States military command in Pearl Harbor, Hawaii, also issues storm advisories using the designations “tropical depression,” “tropical storm,” “typhoon” and “super typhoon.”

Cyclones in the Indian Ocean are classified according to two intensity scales, depending on where they are, with terms like “very intense tropical cyclone” and “super cyclonic storm.”
Australia rates cyclones much the way North America rates hurricanes, in categories from 1 to 5.

As violent as they are, these storms help to regulate the global climate, by moving heat energy away from the tropics and toward the poles.

Naming the storms

Storm terminology has been highly influenced by the histories and cultural interactions of different regions.

“Hurricane” appeared in English in the 16th century as an adaptation of the Spanish word “huracán.” “Typhoon” is variously described as coming from Arabic (“tafa”) or Chinese (“taifeng”), or perhaps both.
“Cyclone” was coined in the late 18th century by a British official in India, from the Greek for “moving in a circle.”

A fascinating look at how a little girl walking in the sand of the African desert could cause a hurricane 4000 miles away.

But a storm by any other name should still be taken seriously.

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Sunday, October 13, 2019


To some, the ocean is a fearsome and dangerous place.
But to others, it’s a limitless world of fun, freedom and opportunity where life can be lived to the full.
A new documentary presented by Patagonia and directed by Keith Malloy, FISHPEOPLE tells the stories of a unique cast of characters who have dedicated their lives to the sea.
From surfers and spearfishers to a former coal miner and a group of at-risk kids in San Francisco, it’s a film about the transformative effects of time spent in the ocean—and how we can leave our limitations behind to find deeper meaning in the saltwater wilderness that lies just beyond the shore.