"turbulence is on the rise" Is it?

[G0ULI]

The very existance of the northern and southern jet streams was unknown until the Second World War. Exploiting them to speed up journey times is an even more recent trend.

We have very little data to assume that the default circulation of the jet streams has been smooth and laminar for eons although historical and physical evidence of climate around the world can be used to infer the track of the jet streams. It may well be that the last fifty years represent a particularly calm period and the jet streams are reverting to more normal circulation.

Alternatively it may be that the many aircraft exploiting the jet stream core are responsible for upsetting the balance of this phenomenon and actually increasing the turbulence of the air flow, as pointed out by other posters.

So this could be an effect of climate change, or an effect of aircraft effectively robbing some of the energy from and disrupting the smooth flow of the jet streams.

Wind farms are known to disrupt local weather patterns, so why shouldn't the presence of hundreds, if not thousands, of wide bodied jets not have a measurable effect? Why is anyone surprised that the aircraft themselves might be responsible?

There are always energy costs associated with moving things from one place to another. If you extract energy from the wind to reduce fuel costs, that energy is lost to the natural weather system and absorbed by the aircraft in order to increase its ground speed. Several thousand aircraft a day, all individually absorbing a little energy, soon adds up to a lot.

I maintain that the accuracy of GPS navigation systems tends to ensure that aircraft all track along very similar courses which can further concentrate the disruption to the normal jet stream flow and the possibility of wake turbulence in otherwise clear air.

I do appreciate there is a difference between CAT and wake turbulence, but the subtleties are probably lost on the passengers in the back when their drinks go flying.

Is there a correlation between a general increase in global temeratures and the average height at which commercial jets fly. In the 1960s 30,000 feet was considered high. Jets are regularly flying at heights in excess of 40,000 feet today. It seems to me that the increase in global temeratures has pretty much tracked the height of the average flight over the Atlantic (and elsewhere) as it has increased. Just how much did Concorde contribute to atmospheric change? There does appear to have been a slight dip or slowing in temerature rise since it stopped flying. There are such a huge number of variables, it will be very difficult to prove the case one way or another for perhaps several decades to come.

So a good project to seek funding for, even if the results may be a long time coming and somewhat inconclusive in ways to mitigate the effect, apart from avoiding flying in the jet stream.