SURVEY OF METEOROLOGY II LAB #2
Global Circulation - Jet Identification and Structure
Lab Objectives:
Examine the structure and location of the subtropical and polar jet streams relative to each other
To examine the relationship between the polar jet and the polar front
Practice identification and locating semi-permanent highs and lows in weather data
ASSIGNMENT:
Do question #2 in your book on page 137.
Use GARP to plot the 250 mb isotachs from the 00UTC AVN model run for today over the northern hemisphere The isotachs should be color filled, starting at 50 kts. Plot contours of isotachs starting at 50 kts, every 10 kts.
For the 36 hr forecast time in the mode run, do you see both the polar and subtropical jets? If so, indicate where they are on a print out of this image.
Now, plot a vertical cross section through the jet at the time and location where the jet(s) was (were) obviously strong. In your cross section, again plot isotachs of wind speed in knots using the same convention as above. Superimpose isotherms (degrees Celsius). Choose an appropriate contour interval so that the plot is not overly cluttered. Print out this graphic.
Do you see any near surface frontal boundaries in the temperature data? If so, comment on their location relative to the jets aloft.
What is the approximate width and depth of the jets? What is their approximate altitude?
Where is the tropopause? Indicate it's position on the diagram. Where are the jets relative to the tropopause?
Now plot water vapor satellite imagery at 12 UTC today over the US. Superimpose the AVN 250 mb isotach data that you plotted in question #2. Print out this graphic.
How does the jet stream appear in the satellite data? In other words, what features in the satellite data determine the jet's position?
Turn in a hard copy of this lab.
READ CHAPTER 4 BEFORE THE NEXT LAB SESSION
last updated: 09/10/04 11:22 AM