"Ah!!"
The plane suddenly jolted violently | giphy
The scream is the instinctive reaction of many passengers to the instant fall of the plane.
In the event of very severe turbulence turbulence, unfastened passengers, items or food on board can be thrown in one piece and hit the ceiling or seat, causing injuries or cuts.
In February 2019, a Delta Air Lines flight experienced severe turbulence
| Scrum Inc.
This sudden and violent jolt usually comes from clear sky turbulence. High in the clear sky, undetectable air turbulence sometimes slammed in, catching everyone on board by surprise.
Last month, a new study said clear sky turbulence is increasing due to climate change, meaning people will likely experience more intense bumps when flying.
The average global temperature is getting higher | WMO
Dangerous clear sky turbulence
At high altitudes, the aircraft can also fly stably when the air flows steadily horizontally. However, if the stability of the air is disrupted, it will flow in a chaotic or random way, creating turbulence.
Thunderstorms are probably the most well-known cause of turbulence. During a thunderstorm, the air will have a strong upward and downward movement, resulting in a lot of turbulence. In addition, turbulence can also be caused by factors such as mountains, rapids high in the sky, and the temperature of the air flow around the aircraft.
You may encounter turbulence when flying over mountains
| ATSB, flightsafetyaustralia
Fortunately, the aircraft is equipped with weather radar, which can detect the weather and some turbulence ahead in advance.
The plane has a weather radar | Aircraft Science
Depending on the reflected echo, the radar display will show the situation ahead in different colors: green indicates a slight bump, yellow represents a slightly stronger but controlled moderate bump, red indicates that the aircraft may be temporarily out of control, and magenta (or magenta) indicates that the aircraft is almost completely out of control.
Different colors correspond to different degrees of bumps
| IntuVue RDR-4000 Pilot's Guide
According to the radar information, the pilot makes a detour in advance to avoid the red and magenta areas. In addition, pilots report turbulence, and air traffic controllers are notified to alert other flights passing through the area.
The plane will bypass areas where there may be severe bumps | JxJ Aviation
However, Clear-Air Turbulence (CAT) is much more troublesome. Above the clouds, high above the clear blue sky, changes in the direction, speed, height and intensity of the air flow can also cause turbulence. Clear sky turbulence pilots do not see, and on-board radars do not detect it.
Regarding clear sky turbulence, "the only information we have is when the plane passed it," said Paul Williams, an atmospheric scientist.
Turbulence sometimes appears suddenly in the clear sky Graeme Marlton
Clear sky turbulence is like a rough wave hidden on the calm sea. In severe turbulence, the vertical movement of the aircraft will exceed gravity. That means, "If you're not wearing a seat belt, you're turning into a catapult and being ejected from the seat," Williams explained.
In extreme cases, people have died from their injuries. In more extreme cases, the body may be damaged or even disintegrated.
A Hawaiian Airlines plane suffered severe turbulence and a cracked ceiling in the cabin Tara Goodall
Clear sky turbulence is increasing
The research paper published in Geophysical Research Letters by Williams and colleagues analyzed atmospheric data from 1979 to 2020 to count the frequency of past clear sky end flows.
The findings show a 41 percent increase in severe clear sky turbulence over the continental U.S. since 1979. Looking back at different periods in the past, although the data has risen and decreased sometimes, it has a clear upward trend in the long run. This is also consistent with the expected impacts of climate change.
Clear sky turbulence over the continental United States increased by 41% | References[1]
The study found that the increase in violent flight bumps over the North Atlantic was the most pronounced — a 55 percent increase, with the duration of intense jolts in the region increasing from 17.7 hours to 27.4 hours per year. There is a very busy flight route here.
Violent jolts over the North Atlantic increased by 55% | References[1]
In addition to strong clear sky turbulence, moderately intense clear sky turbulence also increased by 37 percent — the duration of moderate turbulence over the North Atlantic increased from 70 hours to 96.1 hours per year.
The average duration of aircraft bumps will also increase. On transatlantic flights, for example, passengers may experience a 10-minute bump, but Williams predicts that in decades passengers may be hit by bumps that could increase to 20 minutes or half an hour.
In March this year, a Lufthansa flight was hit by turbulent skies, the plane suddenly crashed, food and various items flew everywhere, and some passengers said that they thought they were going to die... | CBS
Past studies have also noted a significant increase in clear sky turbulence over the North Atlantic, the United States and Europe between 1958 and 2001. On the east and west coasts of North America, clear sky turbulence is more common in winter. There is a similar situation in the eastern part of the continent and eastern Europe.
Williams said that based on climate change models, the frequency of clear sky turbulence in summer and autumn is also expected to increase. "By 2050, summer is expected to be as bumpy as the winter and autumn of 1950."
Higher risk and cost
Each minute of increased turbulence increases the probability of injury, aircraft damage, and maintenance.
"There's really more and more turbulence in the sky," said Sara Nelson, who has 26 years of experience as a flight attendant. Flight attendants are at higher risk of injury than passengers. About 78 percent of injuries caused by turbulence are flight attendants.
"We have flight attendants who have been thrown to the ceiling multiple times and then fallen again, resulting in fractures," Nelson said. Others were unable to work for years after being injured. "Turbulent airflow has always been the biggest threat to the job."
Most of the injuries were flight attendants | SandraTropp
To reduce the risk, some have also called for children under the age of 2 to have exclusive car seats instead of being held in arms or on an adult's lap. Babies have suffered spinal injuries due to turbulence of airflow.
It is estimated that approximately 65,000 aircraft in the United States experience moderate turbulence and approximately 5,500 aircraft experience severe turbulence each year. Turbulence causes about $2~500 million in losses to the U.S. aviation industry every year. Passengers and flight attendants are injured, the aircraft body is more likely to "fatigue", the airframe needs maintenance, there is no benefit from grounding, the aircraft will consume more fuel to avoid some turbulence, etc. all mean higher costs.
In addition, turbulence is a greater threat to small aircraft, which are more susceptible to changes in wind speed.
Airplanes are affected by climate change, and their own CO2 emissions are increasing Our World in Data
To combat more turbulence in climate change, "we should invest in improved turbulence prediction and detection systems," Professor Williams said. Researchers are already developing new techniques to detect clear sky turbulence in advance.
Until more advanced technology arrives, we don't have to worry too much, because in most cases, turbulence is not harmful, sudden severe turbulence is rare, and people who are injured are usually because they are not wearing seat belts at the time.
Wear your seatbelt as fast as possible, regardless of whether the belt indicator is lit or not
| Giphy
Looking at the high temperature warning in recent days, for the sake of safety, it is best for everyone to wear seat belts when flying in the future!
Written by | Cloud
Review | Ah Xian
Resources:
[1] Prosser, M. C., Williams, P. D., Marlton, G. J., & Harrison, R. G. (2023). Evidence for Large Increases in Clear-Air Turbulence Over the Past Four Decades. Geophys. Res. Lett., 50(11), e2023GL103814. doi: 10.1029/2023GL103814
[2] Smith, I., Prosser, M., & Williams, P. (2023, July 03). Aviation turbulence soared by up to 55% as the world warmed -- new research. Retrieved from https://theconversation.com/aviation-turbulence-soared-by-up-to-55-as-the-world-warmed-new-research-207574
[3] Taylor, M. (2023). Climate crisis leading to more turbulence during flights, says study. the Guardian. Retrieved from https://www.theguardian.com/environment/2023/jun/08/climate-crisis-leading-to-more-turbulence-during-flights-says-study
[4] Science, A. (2022, February 25). How Aircraft Avoids Turbulence | Weather Radar System. Youtube. Retrieved from https://www.youtube.com/watch?v=qV0rsIRtQpE
[5] Lane, T. (2023, July 05). What is air turbulence? Retrieved from https://theconversation.com/what-is-air-turbulence-196872
[6] NPR. (2013). Climate Change Could Bump Up Instances Of Turbulence. NPR. Retrieved from https://www.npr.org/2013/04/11/176954629/climate-change-could-bump-up-instances-of-turbulence
[7] Lane, T. (2023, July 06). What is air turbulence? Retrieved from https://theconversation.com/what-is-air-turbulence-196872
[8] Prisco, J. (2022). Why air turbulence could be about to get a whole lot worse | CNN. CNN. Retrieved from https://edition.cnn.com/travel/article/clear-air-turbulence-climate-change/index.html
[9] Christine Chung - The New York Times. (2023, July 06). The New York Times Company. Retrieved from https://www.nytimes.com/by/christine-chung
[10] Baran, M. (2023). Turbulence Is on the Rise. Is Flying Still Safe? AFAR Media. Retrieved from https://www.afar.com/magazine/turbulence-is-on-the-rise-is-flying-still-safe
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Source: Bring Science Home
Original title: The flight bumps that throw people up are increasing, and it is because of it
Edited by Childe