[konschubert]

That’s also what I read:

The poles warm FASTER than the equator. Thus, the global temperature gradients are getting smaller.

And as a result, not only does the Jetstream weaken: as a result, weather patterns become more stable which leads to greater continuous periods of draught or flooding.

[Retric]

Your intuition is incorrect. Global warming increases the jet stream.

“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....

[elevation]

> The poles warm FASTER than the equator

The article cites the Prosser Report which contradicts this claim, but I find it hard to understand how this could be true for very long. Why wouldn't the atmosphere stabilize as gradients diminish?

[photochemsyn]

Because the earth's rotational axis is not perpendicular to incident sunlight (hence dark polar winters). As winter sets in, gradients steepen relative to warming equator. It's all complicated by the general increase of atmospheric water vapor as warming proceeds, which can have different effects depending on whether the water vapor is gaseous or forms cloud droplets, which reflect sunlight. It's a hard physics problem.

[coldtea]

jetstream != gulf stream

[HPsquared]

Jet stream is also driven by temperature differences, like basically all weather. Heat engines.

[Retric]

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....

[HPsquared]

I guess it's like someone putting water on the coals in a sauna and the people feel a huge wave of heat due to the increased heat transfer, even though they've literally cooled down the coals.

[HPsquared]

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

[siffin]

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.