The climate crisis could be making transatlantic flights more bumpy, according to research into the impact of global heating on the jet stream. Jet streams are powerful currents of air at the altitudes which planes fly. . They result from the air temperature gradient between the poles and the tropics, and reach speeds of up to 400kmph. They also sometimes meander. Researchers say previous studies of the speed and location of the fastest part of the north Atlantic jet stream have found only small changes over time, although there are signs it is slowly shifting northward. Experts say the lack of dramatic alterations is because climate change produces competing effects at different altitudes. The latest study, however, took a different approach. “Just because the speed isn’t changing, doesn’t mean the jet stream isn’t changing in other ways,” said Prof Paul Williams of the University of Reading, the lead author of the research. His study, published in the journal Nature, looked at the change in wind speed with height, known as vertical shear. “The higher up you go, the windier it gets,” he said. Using three different datasets based on satellite observations, the team say they identified a 15% increase in vertical shear between 1979 and 2017, consistent with what would be expected from climate change. “The winds and the temperatures are in a certain kind of balance in the atmosphere,” said Williams. “The consequence is that it is impossible to change the temperature patterns without having an effect on the wind patterns.” The increase in vertical shear has important consequences for aircraft. “If that wind shear effect gets too strong and moving from one layer [of air] up to the next there is a big jump in speed, that is what causes turbulence,” said Williams. Story has more details. <br/>
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On the southern fringe of Beijing, a giant starfish-shaped building is about to transform the city’s economy.The new Beijing Daxing International Airport, which cost 80b yuan ($11.3b) to build, will be one of the world’s biggest when it opens in September. The Chinese government wants the airport to be a magnet for businesses and an attraction for locals as well as travellers. “The airport paves the way for, and guarantees, Beijing’s long-term economic growth,” says Yu Zhanfu, a partner at consulting firm Roland Berger GmbH. Yu says he expects it to boost the city’s role as a connection point for domestic travellers and those flying abroad. Daxing is one of many airport projects under way in Asia, collectively costing more than $100b, to accommodate a surge in travel fueled by the region’s rising middle class. The IATA forecasts Asia’s travel demand to surpass that of North America and Europe combined by 2037. About two dozen airports are slated to open over the next six years in cities ranging from Beijing to Mumbai, while many existing airports are adding terminals or runways. Daxing will increase Beijing’s capacity for travellers by more than 70% and alleviate congestion at Beijing Capital International Airport, the world’s second-busiest last year with more than 100m passengers. By year’s end, Shanghai will unveil a $3b, 83-gate terminal that will be separate from the airport’s main building. The number of trips per person in China will increase 11% annually for two decades from 2018, reaching 1.6b by 2037, the IATA predicts, with growth in India reaching 10% a year and Indonesia 9%. That compares with 1% to 2% annual growth in the US and the UK. Ng Mee Kam, director of the urban studies program at the Chinese University of Hong Kong, says governments are coming to view airports as destinations serving local consumers and businesses. “The airport is not just a transportation hub,” Ng says. “It’s becoming a city itself.” Story has more.<br/>
The government is telling airlines and passengers how it will enforce rules governing animals that people bring on planes. The Transportation Department said Thursday that airline employees can bar any animal they consider a safety threat. Airlines, however, can be punished if they ban an entire dog or cat breed, such as pit bulls. The department's enforcement office said that it doesn't plan to stop airlines from asking passengers "reasonable" questions about a service animal's vaccinations, training and behaviour. Airlines can require advance notice if passengers plan to bring an emotional support animal — several already do — but can't impose the same requirement for service animals such as guide dogs for the blind. The number of animals on planes rose rapidly in recent years as more people began bringing a companion for emotional support. Most flying pets are tame, but there have been some well-publicized instances of animals biting passengers or airline employees and other reports of animals relieving themselves in the cabin. The Transportation Department plans to publish the guidelines next week, and airlines will have 30 days after that to conform their rules with the federal policy. Airlines for America, a trade group of major US airlines other than Delta, and the flight attendants' union blamed the large numbers on passengers who fraudulently claim they need an emotional support animal to fly. Airlines must waive pet fees for comfort animals if the owner has a doctor's note vouching for their need to have the animal companion.<br/>
Dozens of flights have been grounded in Melbourne and Sydney as wild winds lash Australia's south-east. Thirty-one domestic flights have so far been cancelled out of Melbourne, mostly because of the weather. No international flights have been affected at this stage. Both Melbourne and Sydney airports have just one runway open for domestic flights, meaning fewer planes can land. Qantas said it had cancelled about a dozen domestic flights by early Friday afternoon. "We're asking customers to check their flight status for updates and we hope to get everyone to their destination today," a Qantas spokesman said. Other passengers were hit with delays and long queues at the airports. Airlines were warning passengers to check their flight status on Friday. "There's windy weather about, which is affecting services across our network. Sorry, we know this blows," Virgin Australia said on Twitter. Jetstar said strong winds in Sydney had caused cancellations and delays to domestic flights.<br/>