UPPER WINDS Flashcards
1
Q
What are upper winds driven by?
A
Pressure gradient at each level
2
Q
How are upper air contour charts drawn?
A
Constant pressure surface, height contours (or isoheights) drawn. The orientation and spacing of contours gives the wind direction & speed.
Close together = strong wind & vice versa
3
Q
What is vertical geostrophic windshear caused by?
Otherwise known as?
A
Mainly due to differences in temperatures.
Thermal winds
4
Q
Why are westerly winds the strongest near mid-latitudes?
A
Tropics receive more radiation than the poles, most of the temp difference is experienced at mid-lats
5
Q
What is a jet stream?
A
A region of strong winds >60kts, can reach in excess of 300kts.
Usually applied to the strong westerly wind belt in upper troposphere.
6
Q
A
