American Meteorological Society DataStreme Atmosphere American Meteorological Society DataStreme Atmosphere

American Meteorological Society DataStreme Atmosphere American Meteorological Society DataStreme Atmosphere

Lab Activities #1
? From the ? American Meteorological Society DataStreme Atmosphere American Meteorological Society DataStreme Atmosphere Web site, print or make a copy of the United States map with surface pressures. (You may have to display the map in “landscape” orientation to have room for the entire U.S. region.)
? Draw isobars from the given data. (View the ? practical isobar drawing example from module 2.) Remember to follow these general rules for drawing isobars:
? Use a pencil when initially drawing isobars.
? Try to make your curves smooth and flowing.
? Draw your isobars at standard 4-mb increments (e.g.: 992, 996, 1000, 1004 …).
? Clearly label each and every isobar line with its appropriate value.
? Do not cross or intersect isobar lines.
? Do not stop an isobar midway within a set of data values.
? Account for every incremental isobar value. (You cannot have a 1000-mb line and a 1008-mb line next to each other without a 1004-mb line in between.)
? You may draw two isobars of the same value next to each other.
? Label any closed isobars with an appropriate H or L.
? Indicate on your map the region in which you would expect the strongest winds. Explain your choice.
? Indicate on your map the region in which you would expect the weakest winds. Explain your choice.
? In this ? activity, figure 7.1 shows an upper-level 500-mb map of the United States displaying isoheights (contours) in solid blue and isotherms in dashed red. On the map, indicate regions of approximate:
? gradient winds
? geostrophic winds
Lab Activities #2
? Plot the following process on the blank Stüve diagram below.
A sample of air with a temperature of 20 degrees Celsius at 1000 mb is moved:
? dry adiabatically from 1000 mb to 850 mb, then
? isothermally from 850 mb to 600 mb, then
? saturated adiabatically from 600 mb to 500 mb, then
? dry adiabatically from 500 mb to 400 mb, then
? isobarically to –50º C

? The Stüve diagram below shows atmospheric conditions over Brownville, Texas (BRO).

? List the following information from the Brownville Stüve:
? the time & date of the sounding in both Zulu time and the city’s local time
? the ground-level air temperature
? the ground-level dew point temperature
? the level (in mb) of the strongest winds (including its direction & speed in knots)
? the level(s) (in mb) which indicate the highest relative humidity
? the level(s) (in mb) which indicate the lowest relative humidity
? the level of the tropopause (in mb)
? the most stable layer of the atmosphere (in mb)
? Knowing that cumuloform clouds tend to form in unstable* atmospheric layers and that stratiform clouds tend to form in stable atmospheric layers, indicate (1) the layers of the atmosphere that should have clouds present and (2) the type of cloud (cumuliform or stratiform) in those layers.
Unstable atmospheres include both absolutely unstable and conditionally unstable conditions.

Lab Activities #3

? Surface low sea-level pressure regions have converging surface winds, while surface high sea-level pressure regions have diverging surface winds. Regions of surface high sea-level pressure tend to be clear, and regions of surface low sea-level pressure tend to be cloudy.
? View Figure 9.2, the ideal 3-Cell Circulation Model, and state which latitudes have belts of surface high sea level pressure, and which latitudes have belts of surface low sea level pressure.
? Based on Figure 9.2, which latitudes experience generally cloudy conditions?
? Based on Figure 9.2, which latitudes experience generally clear conditions?
? Noting those general characteristics, discuss the similarities and differences of the atmospheric features found between the ideal 3-Cell Global Circulation Model and the animated Global Infrared image, Figure 9.3. For any differences noted, explain what you think would be responsible for those differences.
? Figure 9.5 (A and B) shows monsoonal wind patterns across southern Asia. Which panel (A or B) depicts the winter monsoon, and which depicts the summer monsoon? For which monsoon would you most likely need an umbrella in Bombay?
3. Figure 9.6, below, shows isopleths of sea-surface temperature across the Pacific Ocean for November 1982 and November 1988. El Niño was in progress during one of these years. Identify the year and explain your conclusion.