METR 2413 QUIZ #2 Unannounced
Answer all questions briefly. DUE in 12 minutes!
1. Like a good user, you are checking for hung or orphaned processes that gempak may have left running
on rossby or one of the metlab machines. What unix/linux command or commands do you issue (run) in order to clean
up after yourself?
ps -ef | grep [username] or ps -aux |grep [username]
then kill -9 [proccess id number] (4 points)
2. What is the difference between mandatory levels and significant levels in upper air sounding data?
Mandatory levels [1000, 925, 850, 700, 500, 400, 300, 200, 150, 100, 70, 50, 30, 20, 10 hPa]
are those constant pressure levels at which a complete evaluation of the data from radiosondes
is required (by WMO). Significant levels are those levels at which the lapse rate of temperature,
moisture, or wind change, and must be evaluated to get a reasonably accurate portrayal of the
vertical structure of the atmosphere. (4 points)
3. What wavelength (approximately) is used to detect thermal infrared radiation data displayed
on a satellite infrared weather image and why is this wavelength used?
10 - 11 microns approx. This is the atmospheric window region for infrared radiation
so there is little atmospheric absorption by greenhouse gases at these wavelengths. [This means
that IR radiation in these wavelengths that is received by the satellite is either emitted by the
surface (warmer temperatures, darker in the image)
or absorbed and re-emitted by clouds (colder temperatures, so brighter image)]. (4 points)
4. Decode the following METAR (NOTE THE UNITS!!!)
KOKC 061152Z 36011KT 10SM CLR M13/M18 A3066 RMK AO2 SLP402 T11331178
11089 21133 58021=
Day/Time = _____ / ______ CST
Decoding the 061152Z group yields the 6th day of
the month at 1152UTC, which in January is 0552CST (subtract 6 hours from UTC
to get to CST, 5 hours for CDT) (2 points)
Temperature = _____ F (to nearest tenth)
Temperature code is M13, or -13°C, and in the remarks section is T1133, or -13.3°C.
Multiply -13.3C by 1.8, then add 32.0 = 8.1°F (2 points)
Dew Point = _____ C (to nearest tenth)
Dew Point code is M18, or -18°C, and in the remarks section is T11331178, or -17.8°C.
(2 points)
Wind Speed = _____ kt
Wind code is 36011KT, wind speed is 11 knots. (1 point)
Wind Direction = _____ (compass direction, not degrees!)
Wind code is 36011KT, wind direction is 360 degrees. Compass direction is North (N). (1 point)
Total = 20 points