The Northern Hemisphere Jet Stream is suggested to have two states, rigid or wavy, zonal or meridional. The stable state brings rigid Jets and the less stable state brings wavy Jets. In the stable state the Jet is usually North or South of a given place say Minnesota. In the less stable state, the Jet appears to jump North or South frequently as in diagram c). The orb will to someone in Minnesota, be in one of two tracks. With a wavy jet it is suggested that cold and warm air masses are mixing their content in Earth’s attempt to cool itself. Tsonis 2007 gave me this idea when they wrote about a wave-2 and wave-3 anomaly. Jennifer Francis published some zonal meridional wind data from the Northern Hemisphere that seemed to somewhat match up with the Tsonis paper. What is of great interest to me it how fast the movement is through the Z curve in the wavy state when looked at from one place. Minnesota at times of the year could find itself on the opposite side of the jet as fast every other week. Diagram a) could be the definition of a linear system. Diagram a) could be a frequent state experienced in Minnesota over decadal periods. Yet when diagram c) is experienced in Minnesota more frequently, we would think the system has rearranged itself. I am suggesting this would be a temperature induced change to the system. That linear under increasing temperatures does not just drift upwards or sideways, we get a Z curve. Z curve results may suggest temperature plateaus where air mass mixing cools the Earth.
Diagram above from: http://www.sparcs-center.org/key-concepts/tipping-points-and-resilience.html