PPT part 2 Flashcards
A confluent trough
confluent and curvature figure
a confluent trough has
major and minor development areas
a confluent trough figure
confluent trough and ridge figure
diffluent trough and ridge figure
How features evolve
- amplification
- ridges amplify
- extension
- troughs extend
- also known as sharpening
- declining
- ridges decline
- relaxation
- troughs relax
diffluent trough (extends/sharpen) & (relax)
diffluent ridge (amplification/sharpens) & declines
diffluent ridge - confluent trough
give rapid ……………………..
rise of pressure
diffluent trough - confluent ridge
gives rapid
fall of pressure
Jet propagation steps
- consider an air parcel entering a jet
- the parcel accelerates into the jet as PGF increases
- air is transported across the jet entrance
- which leads to areas of convergence and divergence aloft
- and the reverse happens at the jet exit
- remember Dines’ two layer model -> vertical motion
- Descending air warms adiabatically - ascending air cools adiabatically
- warming decrease temperature gradient at jet enterance -> jet weakens
- cooling increases temperature gradient at jet exit -> jet strengthens
which leads to areas of convergence and divergence aloft
and the reverse happens at the jet exit
(figure)
which leads to areas of convergence and divergence aloft
and the reverse happens at the jet exit
remember Dines’ two layer model -> vertical motion
figure
Jet propagation final figure
blocking patterns