Project 1.  Draw two atmospheric soundings and extract some useful information.

 

  1. Download the following sounding from the University of Wyoming site.  No other sounding is acceptable. Note that  1 hPa = 1 mb.

http://weather.uwyo.edu/upperair/sounding.html

Text list; 2007; December 17; 00Z (to December 17; 00Z) for Tucson, AZ

  1. Print a sheet of graph paper and plot the following two soundings by hand.  You do not have to plot every single point – just enough to see the shape of the sounding, e.g., every second or third point.  Look at the “skew-T gif” at the Wyoming site to get an idea of where the changes occur.  You may use a spreadsheet to plot the data, instead of graph paper if you wish.
    1. On one graph, plot temperature (e.g., from –80 C to +20 C on the x-axis) vs. altitude (e.g., from 0 to 35,000 m on the y-axis).
    2. On a second graph plot pressure (e.g. from 0 to 1,000 hPa on the x-axis) vs. altitude (e.g., from 0 to 35,000 m on the y-axis).
  2. Answer the questions on the following Project Report.
  3. Staple together the Project Report and the graph and hand in your completed project during class on or before the due date (Thursday, 2/7/08).  No more than three pages are allowed.  Points will be subtracted for longer write-ups.

Project 1 Report.  Name/SID:___________________________

 

Draw the best fit straight line through the temperature vs. altitude sounding over the following two ranges:

    1. From the surface to approximately 10,000 m (the troposphere)
    2. From approximately 20,000 m to 27,000 m (the stratosphere)

Calculate the slope of each straight line.  The general formula for the slope of a straight line is:

Slope = change in Y/change in X    =   [Y(2) – Y(1)]/[X(2) – X(1)]

For example, in the troposphere a calculation would look like:

Slope = (9000 m – 900 m)/((–50 C) – (25 C))

Slope = 8100 m/–75C

Slope = –108 m/C

Note that:

The slope in the troposphere is negative (the atmosphere cools as the altitude increases).

The dimensions of “meters per degree centigrade” make sense physically.

Answer the following (show your arithmetic where necessary):

Slope in troposphere = __________________________________________

________________________________________________________________

 

Slope in stratosphere = __________________________________________

________________________________________________________________

 

The slope in stratosphere is positive because: _______________________________________________________________

 

The tropopause begins at approximately: ______________________meters

Inspect the pressure vs. altitude sounding and answer the following:

The altitude at 500 mb (hPa) is: __________________________________ meters

The pressure at Mt. Lemmon (3000 m) is: ____________________ millibars (hPa)

The pressure at the beginning of the tropopause is: ___________ millibars (hPa)