Men are better at navigating than women, according to a massive study, but there's not much for men to be proud about.
Scientists at University College London say the difference has more to do with discrimination and unequal opportunities than any innate ability.
The findings come from research into a test for dementia.
But it has also given an unprecedented insight into people's navigational ability all around the world.
The experiment is actually a computer game, Sea Hero Quest, that has had more than four million players.
It's a nautical adventure to save an old sailor's lost memories and with a touch of a smartphone screen, you chart a course round desert islands and icy oceans.
Introducing Sea Hero Quest, a mobile game created to change the future of dementia research.
The game anonymously records the player's sense of direction and navigational ability.
One clear picture, published in the journal Current Biology, was that men were better at navigating than women.
Prof Hugo Spiers thinks he has found the answer by looking at data from the World Economic Forum's Gender Gap Index - which studies equality in areas from education to health and jobs to politics.
He told the BBC: "We don't think the effects we see are innate.
"So countries where there is high equality between men and women, the difference between men and women is very small on our spatial navigation test.
"But when there's high inequality the difference between men and women is much bigger. And that suggests the culture people are living in has an effect on their cognitive abilities."
Sea Hero Quest has produced a raft of other findings.
Denmark, Finland and Norway have the world's best navigational skills - possibly down to their "Viking blood"
Sense of direction is in constant decline after you emerge from your teenage years
People in wealthier countries also tend to be the best navigators
The deeper the colour, the stronger the country's navigational ability
The popularity of the game has turned it into the world's biggest dementia research experiment.
Being lost or disoriented is one of the first signs of the disease.
The next step in the research is to see if catching sudden declines in navigational ability could be used to test for dementia.
Tim Parry, the director of Alzheimer's Research UK, said: "The data from Sea Hero Quest is providing an unparalleled benchmark for how human navigation varies and changes across age, location and other factors.
"This really is only the beginning of what we might learn about navigation from this powerful analysis."
This project was funded by Deutsche Telekom and the game was designed by Glitchers.
The Bermuda Triangle, a mysterious stretch of ocean between Bermuda, Puerto Rico and the tip of Florida, has allegedly, throughout the years, swallowed a horde of unsuspecting ships, planes and people.
Charles Berlitz's 1974 book kicked off a craze lasting into the 1980's
Sadly our planet’s mysteries have largely been explained
thanks to the proliferation of TV channels with midweek schedules to fill.
Many tales have been told about the vanishings.
Aliens captured the humans for research.
Some geomagnetic storm confused the pilots' navigational systems.
The lost continent of Atlantis sucked the vessels into its grasp with a mysterious, unidentified force.
Better yet, strong vortexes slurped the victims straight into another dimension.
But scientists throughout the years have pointed out that there are plausible explanations for the vanishings, and that the risks of traveling through the Bermuda Triangle are no different than other spots in the ocean.
The SS Marine Sulphur Queen, a converted T2 tanker ship carrying molten sulfur (sulphur is the British spelling of sulfur) and 39 crew members, disappeared near the southern coast of Florida.
It was last heard from on Feb. 4, 1963, when it sent a routine radio message.
When it failed to make further communication, search crews were dispatched to locate it.
After more than two weeks of looking, the rescue team only found a few shards of debris and life preservers, shown above.
It's a bit unsettling that the Sulphur Queen vanished into "the Devil's Triangle," since folklore says that the king of the underworld reeks of sulfur — and what's that creepy shadow in the photo's background, anyway?
New life has been breathed into one such theory: that the vessels could have easily been overcome by giant and unexpected rogue waves.
This hypothesis isn't new, but a group of U.K. scientists recently discussed the evidence for freak waves and other theories (including the role of human error) in a three-episode documentary series "The Bermuda Triangle Enigma," produced by the BBC for Channel 5.
This photo shows the U.S.S. Cyclops (AC-4), a massive collier ship that was lost at sea in 1918.
After leaving Barbados for Baltimore, Md., on March 4, the vessel vanished without a trace, taking 306 crew members and passengers with it.
It remains the single largest loss of life in U.S. Naval history that was not the result of combat.
"There is no doubt this area is prone to rogue waves," Simon Boxall, an oceanographer at the University of Southampton and one of the scientists on the team, told Live Science.
They are possible "anywhere you get multiple storms coming together."
The USS Nereus (AC-10) was one of four Proteus-class colliers built for the U.S. Navy during World War I. The craft was named after the mythological Greek sea god Nereus, protector of sailors.
The USS Nereus was lost at sea sometime after Dec. 10, 1941, as it made its way to Portland, Maine, from St. Thomas in the Virgin Islands.
It disappeared with a crew of 61 along the same route as its sister-ship, the USS Proteus, had vanished from the previous month.
The USS Proteus (AC-9) was a Navy collier that had been converted into a merchant ship.
It was never heard from again after Nov. 23, 1941, when it left port from St. Thomas in the Virgin Islands, bound for an East Coast port in the United States.
The approximately 540-foot-long (165 meters) ship was carrying 58 men and a cargo of bauxite ore to be made into aluminum.
Two of Proteus's three sister-ships, the Cyclops and Nereus, also vanished without a trace in the Bermuda Triangle.
Rogue waves are steep and tall, like "walls of water," and they often hit unexpectedly, according to the National Oceanic and Atmospheric Administration.
The tip of South Africa, for example, is very prone to them, where waves from storms in the South Atlantic Ocean, the Indian Ocean and the Southern Ocean all come together at once, Boxall said.
Indeed, there were similar disappearances of big container vessels and tankers off the tip of South Africa throughout the years, he said.
This also holds true for the Bermuda Triangle, where storms can come from all directions, like Mexico, the equator and farther east in the Atlantic.
If each wave can reach over 30 feet (10 meters) tall, occasionally they can coincide at the right moment and create a rogue, or "freak," wave that can be over 100 feet (30 m) high.
Engineers at the University of Southampton in England built some ship models, including one of the USS Cyclops, a vessel that vanished in the Bermuda Triangle in 1918 with over 300 people on board.
They simulated rogue waves in a wave tank and found that, indeed, ships can sink quickly if hit by them.
The bigger the ship, the bigger the difficulty staying afloat, they found.
Small ships can get swamped by them, but sometimes they can ride the wave if they hit it bow-on, Boxall said.
But big ships — designed to be supported in the front by the top of one wave and in the back by the top of another — snap in two.
Gas bubbles, magnetic anomalies…humans being humans?
People often talk about weird magnetic anomalies over the Bermuda Triangle, Boxall said.
"There aren't any," he said.
There are magnetic anomalies in the world that have to do with the Earth's mantle moving beneath the crust, but the nearest one is about 1,000 miles [1,600 km] south, off the coast of Brazil — a long way away from the Bermuda Triangle, he said.
Another theory has to do with pockets of explosive methane gas that could, due to some disturbance, float up toward the water's surface and cause the water to be less dense than the ship, leading the ship to sink.
However, no experiment to date has been able to prove that this is possible, Boxall said.
"Theoretically, it could be happening, but there are lots of places in the world where this can happen," not just in the Bermuda Triangle, Boxall said.
Instead, he thinks the most common cause for the mysterious vanishings is human error.
The Bermuda Triangle's eerie reputation
began on Dec. 5, 1945, when flight 19, a squadron of five U.S. Navy
torpedo bombers, vanished into thin air during a routine training
The planes were
fully equipped and had been thoroughly checked before they departed from
the Naval Air Station Fort Lauderdale in Florida.
made the disappearance even more mysterious is that it occurred during
peacetime, making it less likely that they were shot down.
This photo shows a U.S. Navy TBF Grumman Avenger flight, similar to the Flight 19 planes.
losing radio contact off the coast of southern Florida, Flight 19's
flight leader was reportedly heard saying: "Everything looks strange,
even the ocean," and "We are entering white water, nothing seems right."
aircrafts and 14 crew members were never found, despite a lengthy
investigation by the government. In fact, a search-and-rescue aircraft
with 13 men onboard was dispatched to locate the missing planes, but
that aircraft and its passengers also inexplicably disappeared.
The famous disappearance of Flight 19 — five U.S. Navy aircraft that vanished during a training mission in 1945 — that led one journalist in 1964 to give the area its current name, probably occurred because the crew got lost and ran out of fuel, Boxall said.
About a third of all registered and privately owned ocean craft in the U.S. are in the states and islands of the Bermuda Triangle area, he said.
And according to the most recent 2016 figures from the Coast Guard, 82 percent of incidents in this area that year involved people who had no formal training or experience of being at sea, he added.
"So, you take a third of the entire boating population of the U.S., you dump them in the Bermuda Triangle," and what you get is mysterious vanishings, Boxall said.
You don't need any licensing or specific equipment like radios or navigation maps to take a boat to sea, he added.
"A number of times, working at sea, we've come across people who are navigating using a road map, who are relying on their mobile phones as their means of communication, discovering … you get 30 miles offshore [and] you lose the signal," Boxall said.
Retrieving sunken planes and ships from the Bermuda Triangle is especially difficult because it is home to the Puerto Rico Trench, which reaches depths of about 30,100 feet (9,200 meters) and is the deepest part of the Atlantic Ocean.
Crafts that sink to such low points are seldom seen again.
This underwater photo shows an unidentified Caribbean shipwreck discovered by NOAA oceanography researchers on April 1, 2011.
In addition, "environmental considerations could explain many, if not most, of the disappearances," NOAA wrote on its website.
"The ocean has always been a mysterious place to humans, and when foul weather or poor navigation is involved, it can be a very deadly place."
NOAA also says the area could be prone to accidents because of the Gulf Stream, a strong and fast ocean current that can cause "rapid, sometimes violent, changes in weather," and shallow waters around the Caribbean islands that can prove fatal for ships.
"You can extend the Bermuda Triangle to ever bigger areas…what you'll find is that the Bermuda Triangle covers the entire globe," Boxall said.
"Rogue waves can hit lots of different places, methane bubbles can hit lots of different places, and wherever you get a high concentration of amateurs without any experience you're going to get a high concentration of mysterious disappearances."
But, you know, maybe it is aliens capturing unsuspecting humans using vortexes that lead straight into their laboratories that they've set up in the lost city of Atlantis.
What sort of life do you associate with Antarctica?
Penguins? Seals? Whales?
Actually, life in Antarctic waters is much broader than this, and surprisingly diverse.
Hidden under the cover of sea-ice for most of the year, and living in cold water near the seafloor, are thousands of unique and colourful species.
An underwater robot has captured a rare glimpse beneath the Antarctic sea ice, revealing a thriving, colourful world filled with coconut-shaped sponges, dandelion-like worms, pink encrusting algae and spidery starfish.
The footage was recorded on a camera attached to a Remotely Operated Vehicle (ROV) deployed by Australian Antarctic Division scientists under the sea ice at O’Brien Bay, near Casey research station in East Antarctica.
Our research has generated new techniques to map where these species live, and predict how this might change in the future.
Biodiversity is nature’s most valuable resource, and mapping how it is distributed is a crucial step in conserving life and ecosystems in Antarctica.
The ocean surrounding the Antarctic continent is an unusual place.
Here, water temperatures reach below freezing-point, and the ocean is covered in ice for most of the year.
While commonly known for its massive icebergs and iconic penguins, Antarctica’s best-kept secret lies on the seafloor far below the ocean surface.
In this remote and isolated environment, a unique and diverse community of animals has evolved, half of which aren’t found anywhere else on the planet.
These solitary sea squirts stand up to half a metre tall at 220m depth in the dark, cold waters of East-Antarctica.
Images such as this one were taken with cameras towed behind the Australian Icebreaker Aurora Australis.
Australian Antarctic Division
Colourful corals and sponges cover the seafloor, where rocks provide hard substrate for attachment.
These creatures filter the water for microscopic algae that sink from the ocean surface during the highly productive summer season between December and March.
In turn, these habitat-forming animals provide the structure for all sorts of mobile animals, such as featherstars, seastars, crustaceans, sea spiders and giant isopods (marine equivalents of “slaters” or “woodlice”).
Most Antarctic fish have evolved ‘anti-freeze blood’ allowing them to survive in water temperature below zero degrees C.Australian Antarctic Division
Mapping biodiversity is hard
Biodiversity is a term that describes the variety of all life forms on Earth.
The unprecedented rate of biodiversity loss is one of the biggest challenges of our time.
And despite its remoteness, Antarctica’s biodiversity is not protected from human impact through climate change, pollution and fisheries.
Although scientists have broadly known about Antarctica’s unique marine biodiversity for some time, we still lack knowledge of where each species lives and where important hotspots of biodiversity are located.
This is an issue because it hinders us from understanding how the ecosystem functions – and makes it hard to assess potential threats.
Why don’t we know more about the distribution of Antarctic marine species?
Primarily, because sampling at the seafloor a few thousand metres below the surface is difficult and expensive, and the Antarctic continental shelf is vast and remote.
It usually takes the Australian Icebreaker Aurora Australis ten days to reach the icy continent.
A selection of the diverse and colourful species found on the Antarctic seafloor.
Huw Griffiths/British Antarctic Survey
To make the most of the sparse and patchy biological data that we do have, in our research we take advantage of the fact that species usually have a set of preferred environmental conditions.
We use the species’ relationship with their environment to build statistical models that predict where species are most likely to occur.
This allows us to map their distribution in places where we have no biological samples and only environmental data.
Critically, until now important environmental factors that influence the distribution of seafloor species have been missing.
Using predictions to make a map
In a recent study, we were able to predictively map how much food from the ocean-surface was available for consumption by corals, sponges and other suspension feeders at the seafloor.
The science behind linking food-particles from the ocean surface to the biodiversity of Antarctic seafloor fauna.
Satellites (1) can detect the amount of algae at the ocean-surface.
Algae-production is particularly high in ice-free areas (2) compared to under the sea-ice (3).
Algae sink from the surface (4) and reach the seafloor.
Where ocean-currents are high (5), many corals feed from the suspended particles.
In areas with slow currents (6), particles settle onto the seafloor and feed deposit-feeding animals such as seacucumbers.
Jansen et al. (2018), Nature Ecology & Evolution 2, 71-80.
Although biological samples are still scarce, this allowed us to map the distribution of seafloor biodiversity in a region in East Antarctica with high accuracy.
Further, estimates of how and where the supply of food increased after the tip of a massive glacier broke off and changed ocean conditions in the region allowed us to predict where abundances of habitat forming fauna such as corals and sponges will increase in the future.
Antarctica is one of the few regions where the total biomass of seafloor animals is likely to increase in the future.
Retreating ice-shelves increase the amount of suitable habitat available and allow more food to reach the seafloor.
Colourful and diverse communities are also found living in shallow waters.
Australian Antarctic Division
For the first time in history, we now have the information, computational power and research capacity to map the distribution of life on the entire continental shelf around Antarctica, identify previously unknown hotspots of biodiversity, and assess how the unique biodiversity of the Antarctic will change into the future.
It is a bright morning in the eastern Mediterranean, and a small robotic watercraft operated by Greenpeace, an environmental group, is quietly approaching two fishing boats about 160 miles north of Egypt’s coast.
Unseen by the boats’ captains and crew, the bobbing drone takes a few pictures, and its on-board image-processing systems swiftly determine that illegal drift nets have been deployed.
The fishermen hope to catch endangered bluefin tuna, but such nets can also ensnare dolphins and sea turtles.
The drone fires off a message via satellite and continues to shadow the fishing boats from a distance.
Five hours later a hastily dispatched cutter arrives, and officers from Egypt’s coast guard seize both boats and arrest their crews.
The drone, meanwhile, dips beneath the surface and continues on its monitoring mission.
That, at least, is how things could play out in the early 2030s, if proponents of aquatic drones have their way.
As the cost of building and operating such vehicles drops, satellite communications systems provide cheaper and faster connectivity, and machine intelligence improves, drones could provide a powerful means of policing illegal activities that take place, unseen, at sea.
Powered by wave action, wind power or solar panels, drones could operate for months or even years at a time, scanning large areas in swarms, monitoring environmental conditions and alerting human overseers when something looks amiss.
If drones ruled the waves, fisheries would be more sustainable, pollution would be reduced and human trafficking would be harder to get away with.
Even if drones can monitor only a small fraction of the ocean’s surface, their presence could be a powerful deterrent.
Fishing is just one area where aquatic drones could spot illegal activity.
Today around one-fifth of the annual global catch, worth around $23.5bn, is taken illegally, as fishermen exceed quotas, fish in protected areas or use banned methods such as drift nets or dynamite fishing.
The dumping of pollutants could be detected, too.
By one estimate, vessels intentionally discharge some 276,000 tonnes of oily gunk into the sea each year, nearly half as much as the Deepwater Horizon disaster spewed into the Gulf of Mexico.
Drones could use sensors to sample seawater for traces of improperly dumped fuel sludge, solvents and dirty engine oil, or deploy small, flying cameras to take aerial pictures of tell-tale oil slicks.
In coastal waters, flying “sniffer” drones operated by port authorities could fly through the exhaust plumes of large ships to check that they are not exceeding emissions limits.
(A Danish firm called Explicit uses manned helicopters to sample the exhaust from ships in the North Sea; about 6% break the rules.)
Monitoring air pollution from ships using helicopters and UAVsProject Sense introduces a cost efficient and reliable system for monitoring emissions from ships during cruise using unmanned aerial vehicles (UAV) and helicopters in combination with AIS data and advanced data analysis to sample plumes and detect non-compliant behaviour enabling effective enforcement of applicable emission regulations.
Drones could also tackle human trafficking, and the use of forced labour at sea, by spotting suspicious activity, such as boats that stay in a particular area but avoid visiting port for months at a time.
Tens of thousands of men from Cambodia, Indonesia, Myanmar, the Philippines, Thailand and Vietnam are thought to have been enslaved on fishing vessels that, to prevent escapes, offload their catch and take on supplies from other vessels far out at sea.
Enthusiasm for drone-based monitoring is not driven simply by improvements in drone technology.
It is also a consequence of the high cost of traditional means of enforcement.
Operating a US Coast Guard cutter, for example, typically costs $1,500-3,000 per hour.
And its visibility means nabbing offenders in the act is akin “to catching lightning in a bottle”, says Mark Young, a former head of enforcement for the Pacific Ocean.
Manned aircraft cost more than $10,000 per flight hour.
With today’s technology, says Mr Young, not even America can afford to fully patrol its “exclusive economic zone”, the waters within 200 miles of its shores.
Even less attention is paid to the nearly two-thirds of the ocean that is beyond any country’s jurisdiction.
Satellites are already helping in some areas.
Requiring ships to carry transponders that report their position, for example, can reveal vessels that suspiciously avoid ports or dawdle in marine protected areas.
But not all ships are required to carry transponders, and some captains switch them off.
Roughly half of fishing boats off the east and west coasts of Africa do not transmit their location, Greenpeace says.
These “dark fleet” vessels can be spotted in satellite pictures, but monitoring them in this way is problematic too.
For one thing, a high-resolution photograph of a square region, 10km (six miles) wide, costs about $2,700. SkyTruth, an environmental watchdog based in West Virginia, receives some imagery free from satellite providers.
But shots must be requested and scheduled hours in advance.
On the last 25 occasions when he has made an educated guess as to where a suspect boat would be for a photo 12 hours later, SkyTruth’s most senior analyst, Bjorn Bergman, was right half the time.
(Sea Shepherd, a controversial American conservation group, has dispatched manned “direct action” ships to interfere with rogue Chinese fishing boats that Mr Bergman spotted in the southern Indian Ocean.)
Wave Gliders provide an essential link to connect seafloor to space nearly anywhere in the ocean.
See how the Wave Glider relays information from underwater back to shore.
One firm betting that sea drones are the way forward is Liquid Robotics, a subsidiary of Boeing, an aerospace giant.
Its autonomous, surfboard-sized Wave Gliders use underwater “wings” to harvest energy from the up-and-down motion of waves to travel at one to three knots, or a bit faster using an auxiliary propeller powered by solar panels.
The drones have operated for up to a year at a time and withstood hurricanes.
Onboard systems collect data on submarines, fishing boats and pollution, firing off alerts via satellite to authorities.
Being small and silent, Wave Gliders are unlikely to be spotted by seafarers up to no good, says Gary Gysin, the firm’s boss.
Liquid Robotics has sold more than 400 Wave Gliders, which cost $200,000 or more depending on which sensors are fitted, to outfits including the Australian and American navies and Japan’s coast guard.
Future models will serve as platforms for aerial drones.
The firm sees an emerging “internet of things for the ocean” that reports not just on lawlessness, but also on the health of marine life, water temperatures and currents, to help ships plot more fuel-efficient routes.
Maritime Robotics, a Norwegian firm, sells a much faster surface drone that zips along at a blistering 60 knots under diesel power.
Called Mariner, it can switch to battery propulsion to “sneak in” for a closer look at a suspect vessel, says Vegard Evjen Hovstein, the firm’s boss.
ASV Global (ASV), in partnership with Sonardyne International Ltd., the National Oceanography Centre (NOC) and SeeByte, have successfully delivered a long endurance, multi-vehicle, autonomous survey solution.
ASV Global, the British maker of a similarly fast surface drone, expects sales this year to top $22m, up from $15m in 2017.
Dan Hook, ASV’s head of business development, imagines selling models by 2030 that can dive underwater and stick up a camera and directional microphone on “a little snorkelling mast” to determine what a boat is up to.
Efforts to combat lawlessness at sea are also expected to benefit from spending on aquatic drones by navies.
Pradeep Chauhan, a former head of intelligence for India’s navy, reckons that in addition to their military duties, naval drones will perform the “spin-off” mission of detecting lawbreaking at sea.
Leidos demonstrates maritime autonomy
Nevin Carr of Leidos, a firm based in Virginia that designs submarine-hunting surface drones for the US Navy, in which he served as a rear admiral, says movement-analysis algorithms are being devised to determine what civilian vessels are doing.
That could include identifying ships that are smuggling drugs, weapons or humans, says Jayanath Colombage, a former commander of Sri Lanka’s navy during its fight against the Tamil Tigers, who partly funded their insurgency with such smuggling until being defeated in 2009.
Within ten years Greenpeace expects to have a fleet of aerial, surface and even underwater drones, with the latter seeking, among other things, signs of unlawful seabed mining, says John Murphy, the outfit’s head of drones.
Sea drones are still expensive, but costs will continue to drop because they share so many components with smartphones.
Fees for satellite-data services will also plummet, experts reckon, as new constellations of broadband satellites are launched.
And, says Bjarne Schultz of Norway’s Directorate of Fisheries, analysis of data on individual skippers’ behaviour, and the migratory patterns and market prices of fish, will allow drones to be sent to the areas where illegal activity is most likely to occur.
More broadly, both coast guards and environmental groups believe that maritime drones will make the dispatching of manned patrols far more targeted and cost-effective.
When it comes to preventing lawlessness at sea, swimming robots could be about to make a big splash.
It was a tale of two storms.
The first consisted of the rain and thunder forecast for Bournemouth by the BBC weather app on the Saturday spring bank holiday.
The second came when the first failed to materialise and a tourism manager in the town complained that visitors who stayed away could have come after all and enjoyed sunshine and blue skies.
This opportunity to rage at inaccurate forecasting, bash the BBC and highlight the grievances of small businesses did not go to waste.
For the Sun, it was a “blunderstorm”.
The Mail gave voice to furious social media users whose weekend had been ruined by “crap forecasting” and “total incompetence”.
The Spectator even managed to use the row to take pot shots at climate-change predictions.
So, just another non-storm in a media teacup?
Perhaps, yet the story highlights important questions about how technology is transforming both weather forecasting and our relationship with it.
Is our ability to predict temperature, precipitation and wind speed improving?
If so, how come forecasts can vary so widely depending on which smartphone apps we use?
How long have human meteorologists got before supercomputers and artificial intelligence make them redundant?
And when can we expect 100% accurate forecasts?
The foundation of modern weather forecasting involves gathering huge amounts of data on the state of the atmosphere and Earth’s surface, such as temperature, humidity and wind conditions.
Gaps in the data are filled by extrapolating from available observations and past forecasts.
Forecast models consisting of sets of equations governing physical and chemical processes use this as a starting point to calculate future conditions.
The impact of weather forecasting on human activities is hard to overstate.
A 2011 study by the economist Jeffrey Lazo found that US GDP alone could vary by as much as $485bn (£366bn), depending on the weather.
No wonder huge sums have been invested in improving predictive capabilities.
Meteorologists' ability to predict atmospheric pressures three to 10 days ahead has improved at a rate of about one day per decade since 1981
The number of weather observations has risen dramatically, along with their quality.
The Met Office, for example, is integrating wind-speed data gathered from transponders carried by large aircraft for navigation purposes into its models.
Nasa’s GOES-16 satellite, declared operational in December, scans the Earth much more quickly and in greater resolution than previous satellites.
In February, the UK completed a £10m upgrade of its rainfall radar network, allowing it to deliver five times more data than before.
All this data is fed into “petaflop” supercomputers capable of doing a thousand trillion calculations per second.
These are needed because of the complexity of forecast models that approximate atmospheric processes.
These models have become ever more complex as the science has advanced.
The extra number-crunching firepower also enables “ensemble forecasting”, whereby forecast models are run multiple times using slightly different starting data to explore the probabilities of various outcomes.
This combination of more data, bigger computers and better algorithms has delivered impressive results.
A study published in Nature in 2015 found the ability of meteorologists to predict atmospheric pressures three to 10 days ahead had been improving at a rate of about one day per decade since 1981.
The Met Office says its four-day air pressure forecasts are now almost as accurate as its one-day forecasts were three decades ago.
The digital revolution has transformed how we get and use weather forecasts.
Smartphone apps offer highly localised predictions and wider time frames – from what will happen in the next hour to a fortnight’s time.
There are 8,000 apps with the word “weather” in their title for Android phones and 2,400 for iPhone users.
With so much choice, how can non-experts work out which are most reliable?
Measuring forecasting accuracy is far from simple.
What is most important – temperature, rain or wind conditions?
Is average overall error most useful, or how often a prediction meets reality?
“There are many, many ways to measure forecasting accuracy,” says Eric Floehr, founder of ForecastWatch, a US company that analyses the performance of weather providers.
“Different forecasters perform better on different measures, longer or shorter timeframes or in certain geographical regions.”
AccuWeather’s predictions were best for temperature averages and highs, probability of precipitation and wind speed.
The Weather Channel and Weather Underground came top for low temperature predictions.
Dark Sky came last in all these categories.
In the UK, the BBC app has the most users, followed by the Met Office’s.
In February, the BBC switched from using the Met Office to generate its app forecasts to MeteoGroup, a forecasting company owned by a US private equity group, on grounds, it says, of service quality and value for money.
Floehr provided the Observer with separate data on 12 forecasters covering 29 UK locations during 2017.
In a composite measure of accuracy, the Weather Channel and Weather Underground came top, AccuWeather fifth, MeteoGroup (the BBC’s new provider) sixth and the BBC ninth (based on Met Office forecasts).
On the correct prediction of precipitation, MeteoGroup came fourth overall and the BBC 10th of the 12.
Most regular weather app users will be familiar with the dilemma of trying to decide which to believe when predictions disagree.
Given the improved accuracy of forecasting in recent years, why is there still such wide variation between different providers?
Some forecasters can access more observations than others.
And they use different algorithms based on different forecast models with different levels of detail.
Some apps simply churn out computer models’ predictions, others employ meteorologists to supervise and correct these, especially in unusual or extreme weather.
NOAA hurricane tracking
Which weather forecast should you believe?
“We have unique relationships with governments and companies that allow us to obtain the most relevant, real-time data, and use over 125 global, regional, national and local forecast models, says Jonathan Porter, a vice president at AccuWeather.
“We’re constantly integrating new datasets and enhancing our algorithms.
Our human meteorologists provide an extra layer of expertise when needed.”
Even if the raw data coming out of algorithms used by different forecasters were identical, there could still be differences by the time their reached our screens.
“One big difference between apps is what information they choose to show,” says Derrick Ryall, head of public weather service at the Met Office.
“Some choose to simplify things while others put in a lot detail.
A lot can come down to perception of accuracy.”
Another source of difference between apps is that, contrary to what some might expect, accuracy is not the sole consideration.
In his 2012 book The Signal and the Noise, US statistician Nate Silver highlighted how plotting forecasters’ rain predictions against actual weather showed some consistently erred on the pessimistic side, especially at lower and higher probabilities of rain.
“As a consumer you are going to be a lot more upset with a forecaster if you get rained on and forget your umbrella, than if you don’t have to use the umbrella you took,” says Floehr.
“Because of this, some forecasters tend to over-forecast precipitation.”
Some leading forecasters are now moving away from this approach.
Peter Neilley, a senior vice president at the Weather Company says it stopped having a “wet bias” around three years ago.
“Rather than trying to make judgments ubiquitously about what’s important to people, we pay more attention to the probability of precipitation so people can make their own judgments,” he says.
The BBC app has faced widespread accusations of pessimism.
It now includes hourly percentage chances of rain, which have caused confusion.
“If you try to compare the weather symbol with just the probability of rain you won’t always see a direct correlation because other elements have an influence on that symbol,” said Nikki Berry, a senior meteorologist at MeteoGroup.
The BBC app sometimes displays a daily rain icon even when it predicts a less than 50% chance of rain during just one hour of that day.
“We use the most significant or impactful weather on that day so people aren’t caught out,” says Berry.
She adds that those making important decisions based on forecasts should look beyond weather icons for more detail on the BBC website weather page.
As in many other spheres, advanced computers are increasingly muscling in on roles previously done by meteorologists.
As faster processors take over the grunt work, forecasters are shifting towards the more complex aspects of their profession.
“There is very little human touch to the forecasts people receive on their smartphones,” says Floehr.
“Meteorologists are increasingly focused on communicating forecasts, and helping people turn them into actionable intelligence.
At some point in the next 10-20 years there will no longer be meteorologists in the forecast loop.”
However, those for whom the joy of complaining about the weather is only surpassed by a good moan about forecasters – whether in the media or not – can rest assured.
Science tells us there is no such thing as a perfect weather forecast.
“To know everything about the weather you would need to model every single particle in the atmosphere and all interactions between them,” says Neilley.
“That isn’t even theoretically possible, because the computer doing the modelling would generate heat and become part of the system, and then need modelling.
Putting a thermometer in the air changes conditions a tiny bit.
So no, weather forecasts will never be perfect.”
And the latest forecast is… Smartphone data will soon be improving prediction accuracy
Satellites have been key in driving better predictions one day and more ahead, but are less useful over shorter time scales.
Barometers provide air pressure readings that can help signal imminent changes.
Digital barometers have been included in some smartphones since 2011 to assist location tracking, and around 1bn smartphones can now measure air pressure.
Prof Cliff Mass at the University of Washington has shown smartphone data can help improve the accuracy of short-term air pressure and rain forecasts.
It could also help to predict wind changes.
“Cellphone data could help us better predict things like thunderstorm initiation, and have a big impact in places where we have less data than we’d like,” says Mass, who is also using machine learning to improve the quality of smartphone air-pressure data.
He is working with the Weather Company, which collects 250m pressure readings via its Weather Channel app.
Peter Neilley of the Weather Company said this data should be incorporated into its forecasts during 2019.
Other forecasters, including Dark Sky, have also been experimenting with using smartphone air-pressure data.