Discussion
Just seen a video stating 'Since 1958, turbulence rose 40-90% over Europe and North America... studies suggest global warming could cause it to be worse by 2050'.
Are both statements true or just another chance to bang in GW?
https://www.youtube.com/watch?v=_w6OnK-Djns
Are both statements true or just another chance to bang in GW?
https://www.youtube.com/watch?v=_w6OnK-Djns
A quick google suggests the FAA receive more severe turbulence reports now than in the past even adjusting for growth in traffic. The sticking point is that reported doesn’t mean a growth in encountered necessarily. Was severe turbulence always a Mandatory Occurrence Report? And if so was it a case of the good old days where you’d call it at the high end of moderate to save the paperwork?
Anecdotally in my 10 years as a controller severe turbulence encounters do seem to have become more frequent but I’m not adjusting that for increase in traffic.
Anecdotally in my 10 years as a controller severe turbulence encounters do seem to have become more frequent but I’m not adjusting that for increase in traffic.
Eric Mc said:
Does modern ground based technology - or satellite technology - allow greater detection of turbulence over and above turbulence reports from pilots?
We get SIGMETS published by the met office so I assume they have something that helps them predict it, as for real time detection we rely solely on pilot reports. Generally you can tell it’s going to be rough just by looking at the forecast upper winds, any drastic changes in direction or speed between levels usually means bumps.
Eric Mc said:
Does modern ground based technology - or satellite technology - allow greater detection of turbulence over and above turbulence reports from pilots?
Not so much detection, but prediction. Technology is good at detecting upper winds, therefore forecasters and their computers can have a good stab at predicting clear air turbulence (CAT).It’s generally pretty good - they don’t always get it right, but you can play it safe, and give your cabin crew ample notice to get the cabin ready. A common problem is, if you’re going eastbound over any distance, you’ll want to get into the jet for a piggy-back. That means, at some point, crossing the jetstream boundaries where CAT is prevalent.
Regarding pilot reports, they are useful to a point. Small differences in routeing/aircraft size-altitude can all create significant variations to CAT experience.
However, crossing the oceans, or flying in convoy across southern Russia/northern China on big ‘trunk routes’, youre often only a few minutes behind an aircraft at your level. In which case we communicate via VHF if there’s pertinent information to be shared.
My company alone launches about 14 European flights around midnight, split between 2 aircraft types. All following the same route until the end, and each type weighing roughly similar so at the same level - so a great big conga line. We can communicate via a form of aircraft-to-aircraft text message, which is very handy. It’s certainly the most accurate turbulence forecast I experience.
Edited by Testaburger on Monday 27th August 14:00
Eric Mc said:
I was wondering because sometimes apparent increase in frequency is as much to do with better means of detection.
I’m not sure what you’re saying, Eric.With increased air traffic, there is, presumably a similar increase in pilot reports of CAT. But that’s not really detection - although it aids others in avoidance.
Incidentally, the only means to detect CAT, rather than predict it, is radar at ludicrous requencies - 80GHz.
The technology exists for that, but not aircraft-mounted with sufficient power to provide CAT detection at a practical range. Current weather radars operate around the 10GHz range.
What I'm trying to say is, how better are we now at detecting turbulence using remote sensors than we were in 1958?
In other words, how much can we rely on the frequency of turbulence reports from 1958 compared to today?
Certainly, most airliners of that era flew in a different flight regime compared to present day airliners.
In other words, how much can we rely on the frequency of turbulence reports from 1958 compared to today?
Certainly, most airliners of that era flew in a different flight regime compared to present day airliners.
I'm with Eric; I guess there are three basic differences between 1958 and now - number of aircraft, higher altitudes and possibly more enthusiasm for reporting. All of those add up to 'more turbulence'. I was trying to separate that practical side from the 'OMG it's global warming' type of conclusion which is the default conclusion for so much.
Simpo Two said:
I'm with Eric; I guess there are three basic differences between 1958 and now - number of aircraft, higher altitudes and possibly more enthusiasm for reporting. All of those add up to 'more turbulence'. I was trying to separate that practical side from the 'OMG it's global warming' type of conclusion which is the default conclusion for so much.
Well the test would be are the jet streams stronger than they were in the 50’. Surely there’s data on that somewhere?Problem with turbulence is it's a very subjective phenomena.
One person's idea of 'Light' turbulence, can be someone else's 'Severe' (from experience!).
Also, historical data on winds aloft can not give a true indication of expected turbulence.
I've sat in 200+ mph winds and it's been smooth flying, then a week later been sat in the same bit of airspace in zero wind and spilling my brew everywhere.
It's just one of those things. . . .
One person's idea of 'Light' turbulence, can be someone else's 'Severe' (from experience!).
Also, historical data on winds aloft can not give a true indication of expected turbulence.
I've sat in 200+ mph winds and it's been smooth flying, then a week later been sat in the same bit of airspace in zero wind and spilling my brew everywhere.
It's just one of those things. . . .
djc206 said:
Well the test would be are the jet streams stronger than they were in the 50’. Surely there’s data on that somewhere?
The fact is in the 1950s the numbers of aircraft encountering jet streams would be a lot less than nowadays - so the data would have been less complete and extensive.Eric Mc said:
The fact is in the 1950s the numbers of aircraft encountering jet streams would be a lot less than nowadays - so the data would have been less complete and extensive.
The problem is, data on CAT zones is far too dynamic to ‘database’.Jetstream forecasting is as good as its ever been, obviously, but CAT forecasting remains predictive - and a best guess.
Pilot reporting of CAT is not shown on the weather charts we use to study high-altitude weather along a route. One of the reasons being that they are entirely subjective, and CAT zones are moving, often rapidly.
Pilot reports are issued to us in flight. Yes, I’m sure they’re more commonplace than the 50s, but it’s not entirely routine either. I haven’t received or passed one for a good few weeks.
So, and my opinion only, is that CAT forecasting is better than the 50’s - but the main credit for that goes to the met office computers which predict them based on jetstream detection.
Short term pilot reports are a nice little aide to other aircraft in the vicinity, but a far, far smaller part of the picture when it comes to CAT forecasting.
On the way back from Tenerife
The pilot said on the way here we had it blah blah blah
Anyway two mins later a few bumpy bits.
The belt lights came on
Then it really started. Lockers were flying open and kids spewed up
Couples were holding hands,
Bloke next to me burnt his leg with his tea,
Women started crying,
My own natural reaction was to laugh.
Didn’t bother me,
If it’s a thing you can get out of you do, if you can’t then I don’t tend to,worry about it
me and my lad were smirking,
Then he shouts
“we’re all going to die”
Then some buzzers started in the galley,
And the meal trolleys were rattling like mad
Five mins later calms down lights off kids get changed in the loo panic over
Didnt bother me passed half an hour on
Off the Portugal coast it was
The pilot said on the way here we had it blah blah blah
Anyway two mins later a few bumpy bits.
The belt lights came on
Then it really started. Lockers were flying open and kids spewed up
Couples were holding hands,
Bloke next to me burnt his leg with his tea,
Women started crying,
My own natural reaction was to laugh.
Didn’t bother me,
If it’s a thing you can get out of you do, if you can’t then I don’t tend to,worry about it
me and my lad were smirking,
Then he shouts
“we’re all going to die”
Then some buzzers started in the galley,
And the meal trolleys were rattling like mad
Five mins later calms down lights off kids get changed in the loo panic over
Didnt bother me passed half an hour on
Off the Portugal coast it was
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