C11 - Upper Winds and Jet Streams Flashcards
The Wind at higher levels are faster than those at the surface. Why is this (2)?
- Reduction of Density.
- Varying Temperature between different Air Masses.
True or False. The Pressure difference at the Surface with relation to the Winds, are always the same in Upper Winds?
True.
What type of Pressure will you find over Cold and Warm Air (2)?
- Cold Air = Low Pressure.
- Warm Air = High Pressure.
What is Buys Ballot’s Law for Upper Winds in both Hemispheres (2)?
- Northern Hemisphere, with your back to the Wind, the Cold Air is to your Left.
- Southern Hemisphere, with your back to the Wind, the Cold Air is to your Right.
What Flight Level would you be at with a Pressure Level of 700 hPa?
FL 100 / 10,000 ft.
What Flight Level would you be at with a Pressure Level of 300 hPa?
FL 300 / 30,000 ft.
What Flight Level would you be at with a Pressure Level of 150 hPa?
FL 450 / 45,000 ft.
What Flight Level would you be at with a Pressure Level of 500 hPa?
FL 180 / 18,000 ft.
What Flight Level would you be at with a Pressure Level of 200 hPa?
FL 390 / 39,000 ft.
What is the term given to the Cold Air movement across the Poles using Buys Ballot’s Law?
Westerly.
True or False. The Speed of Upper Winds Increase due to Latitude?
True.
Approximately how many knots of increase in Wind can you find at 20° Latitude?
20 kt.
Approximately how many knots of increase in Wind can you find at 60° Latitude?
40 kt.
What is the term given to the Wind found in the Equatorial Region?
Easterly.
When do Easterly Winds become apparent?
During the Hemisphere’s Summer.
At what speed would you classify Upper Winds as a Jet Stream?
> 60 kt.
What is fundamental in creating a Jet Stream?
Strong Temperature Gradient.
What is the Length, Width and Depth of a Jet Stream (3)?
- Length = 2,000 NM.
- Width = 200 NM.
- Depth = 2 NM.
Name four types of notable Jet Streams?
- Sub Tropical.
- Polar Front.
- Artic Front.
- Tropical Easterly.
What are the Latitudes of a Sub Tropical Jet Stream found during Summer in both Hemispheres (2)?
- Northern Hemisphere = 40° N.
- Southern Hemisphere = 20° S.
What are the Latitudes of a Sub Tropical Jet Stream found during Winter in both Hemispheres (2)?
- Northern Hemisphere = 20° N.
- Southern Hemisphere = 40° S.
True or False. The Sub Tropical Jet Stream are Seasonal?
False. They are permanent.
What is the average Height and Pressure of the Sub Tropical Jet Steam (2)?
- 40,000 ft.
- 200 hPa.
When is the stronger Sub Tropical Jet Stream found?
Winter.
What type of Air does the Polar Front separate (2)?
- Cold Polar Maritime Air.
- Warm Tropical Maritime Air.
In the Northern Hemisphere, with your back to the Upper Winds, where will you find the Cold Polar Maritime Air?
To your left.
At what Latitude can you find the of a Polar Front Jet Stream during the Summer in both Hemispheres?
60° N / S.
At what Latitude can you find the of a Polar Front Jet Stream during the Winter in both Hemispheres?
40° N / S.
What is the average Height and Pressure of the Polar Front Jet Steam (2)?
- 30,000 ft.
- 300 hPa.
What is the average speed of the Polar Front Jet Stream?
80 to 130 kt.
True or False. The Polar Front Jet Stream are Permanent?
True.
What is an Artic Front?
A Frontal Boundary separating Cold Artic Air and Warmer Polar Air.
True or False. The Artic Front Jet Stream is found in both Hemispheres?
False. Only the Northern Hemisphere.
At what Latitude would you find the Artic Front Jet Stream?
60° N.
What is the average Height and Pressure of the Artic Front Jet Steam (2)?
- 20,000 to 25,000 ft.
- 400 to 450 hPa.
True or False. The Artic Front Jet Stream are Permanent?
False. Only found during Winter.
At what Latitude would you find the Tropical Easterly Front Jet Stream?
10 to 20° N.
What is the average speed of the Tropical Easterly Jet Stream?
< 100 kt.
What is the average Height and Pressure of the Tropical Easterly Jet Steam (2)?
- 40,000 to 45,000 ft.
- 100 to 200 hPa.
True or False. The Tropical Easterly Jet Stream are Seasonal?
True.
What does CAT stand for?
Clear Air Turbulence.
How any Metres are there in a Decametre found in a Contour Chart?
1 da = 10m.
