Cyclone and Steep Meander Trough Case Studies
Six events during which a deep cyclone intensifies simultaneously with a steep trough in the upper jet of the Gulf Stream. The joint development has similar aspects for all six events:
- The center of the deep cyclone is shifted downstream of the center of the upper trough.
- The trough axis rotates counterclockwise during the event as the low pressure center translates slowly downstream.
- The cross-frontal component is frequently > 20 cm s-1, offshore (to the right) entering troughs and onshore (to the left) entering crests.
- The ultimate fate of each event varied, with some of the events ending with ring pinch-off and others with the fields relaxing as upper and lower layer centers became more aligned.
- Anticyclones in the deep pressure field develop upstream and northward of the northern edge of the downstream loop of the meander trough in 3 events: May, June, and July 1989.
