From the very beginning in the 1980’s I stated that if the line in the sky was not a jet stream, it had to be a deformation zone. For large cloud patterns that is true but if we look closer, well everything is a deformation zone. It all depends on the spin you put on those cloud lines. Let’s take a closer look at jet streams from the very start.
Rotation is vorticity. Simple. Rotation results from either speed shear or curvature. That’s all there is to it. Simple too! Speed shear resulting from a puff of wind creates a three dimensional ring of rotation – the unified swirl theory – Bob and I are crushin’ that. Curvature of a flow will also cause rotation. The curvature will increase the sense of rotation on one side of the stream lines and decrease the opposite sense of rotation on the other. If you can visualize the three dimensional smoke ring of rotation, imagine how bending the curvature of the flow will concentrate the smoke ring on the bent side while spreading it out on the opposite. Clearly Bob Dylan was considering these questions when he started his smoke ring experiments in 1963.
Now what happens when we have a series of smoke rings and how do we make them? This is where the jet stream is the best example of a strong, linear wind. I used to refer to everything as an axis of maximum winds because the same processes occurs on smaller scales as long as it is a relative maximum in the flow. Here we can get over that and just call everything a jet stream to make it simpler.
There are three conceptual models that we can create to explain what patterns we might see associated with this long puff of moving air.
The perfect jet stream created by a perfectly linear temperature gradient between the warm equator poles and the cold poles might look like the purple arrow below. Imagine the three dimensional ring of rotation surrounding the jet stream. The smoke ring might look like an endless donut resulting purely from speed shear along the entire length of the wind. North is directed toward the top of the page and we are looking down at the atmosphere.