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Is Clear Air Turbulence becoming more common?

flightradar24.com

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Re: Is Clear Air Turbulence becoming more common?

#21

Post by piombisallow »

gosub100 wrote: post #14
nytesky wrote: post #9

I wonder if this is like an immune system response by mother nature, it’s attacking the thing that’s warming it up i.e. air travel? Self correcting systems

couldn't possibly be due to more planes flying more flights.

They haven't actually analyzed reported turbulence, it's just a simulation study: "Turbulence data from aircraft could also be analyzed, but the time period for which quantitative, automated measurements are available is far shorter than the 42 years covered here, making trend detection problematic."

Re: Is Clear Air Turbulence becoming more common?

#22

Post by osipov »

Commercial pilot here. Instead of climate change, we should be talking about continuous descent profiles (CDPs) that have become more common in the past years 5-10 years. These profiles with idle engines allow for a smoother, more fuel-efficient descent by reducing the need for level-off segments. However, CDPs can increase the perception of turbulence during descent. This is because aircraft remain at higher altitudes for longer periods, where atmospheric instability and wind shear are more pronounced. This increased turbulence is not due to climate change but rather the result of these optimized descent procedures aimed at reducing fuel consumption and minimizing environmental impact.

Re: Is Clear Air Turbulence becoming more common?

#23

Post by sandywaffles »

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) .

Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

Re: Is Clear Air Turbulence becoming more common?

#24

Post by hiatus »

sandywaffles wrote: post #23

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) . Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

> Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

I didn't realize private jets fly so high. What's the reason for the difference in elevations?

Re: Is Clear Air Turbulence becoming more common?

#25

Post by siffin »

HPsquared wrote: post #18
Retric wrote: post #17

Earlier quoted context omitted.

It’s a heat engine but more than just temperature changes are occurring. “The new study, by University of Chicago Professor Tiffany Shaw and NSF NCAR scientist Osamu Miyawaki, uses climate models to show that climate change intensifies this density contrast because moisture levels for air above the tropics will increase more than above the poles.” https://news.ucar.edu/132935/jet-stream-winds-will-accelerat... .

Fair enough, I guess it's a pretty non-linear system!

I also think some of the confusion is coming from the use of the term 'weakening'. It is true that the primary jetstream wind pattern is weakening relative to it's stabler state.

That weakening means the jetstream meanders more, with more latitudinal movement in its form.

The strength overall of the jetstream wind is weaker when it's meandering, but can also be much more intense in places.

This says nothing about humidity or energy or pressure, just windspeed and direction.

Re: Is Clear Air Turbulence becoming more common?

#26

Post by cinntaile »

sandywaffles wrote: post #23

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) . Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

Why do they fly higher? I expected them to fly lower.

Re: Is Clear Air Turbulence becoming more common?

#27

Post by pc86 »

hiatus wrote: post #24
sandywaffles wrote: post #23

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) . Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

> Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+. I didn't realize private jets fly so high. What's the reason for the difference in elevations?

Private jets don't really fly at 50k that often but I'm sure there are some that can. 40-42k is pretty common though. There are a handful of reasons. In no particular order: 1) additional separation between recreational private flights and scheduled commercial flights 2) higher performance in small private jets with typically less than 1k lbs of people and cargo 3) winds are generally faster the higher you go so you'll usually go about at high as you're able, at least in one direction.

Most private jets aren't someone flying a billionaire around in a $60M Gulfstream, they're $3M toys being flown around by the owner to go to their ski trip.

Re: Is Clear Air Turbulence becoming more common?

#28

Post by ddoolin »

hiatus wrote: post #24
sandywaffles wrote: post #23

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) . Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

> Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+. I didn't realize private jets fly so high. What's the reason for the difference in elevations?

Traffic separation. Since they can fly at those altitudes, it makes sense to put them there, away from other commercial airliners.

Re: Is Clear Air Turbulence becoming more common?

#29

Post by w14 »

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. (https://www.ntsb.gov/safety/safety-studies/Documents/SS2101....)

I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

Re: Is Clear Air Turbulence becoming more common?

#30

Post by pc86 »

sandywaffles wrote: post #23

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) . Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

Ah yes those pesky billionaires putting the tropopause right below where all their private jets fly.
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