1. Where can I find the US Standard Atmosphere?
USA Today"Understanging Density Altitude"
USA TodayTable
UCSDDiagram
Stanford Calculator
Another Table
AnInteresting Story
Handbookof Space Astronomy and Astrophysics
Handbookof Space Astronomy and Astrophysics (part II)
2. What is the difference between "mass mixing ratio" and "mixingratio"? For that matter, what's a mixing ratio?
The mixing ratio of anything is the amount ofthat something divided by the total amount of everything. For example,in a "normal" population of people, the mixing ratio of women is 0.50 (50%,or darned close to it). The mixing ratio of people with cellular phonesmight be 0.10. In dry air, the mixing ratio of oxygen is 0.21, nitrogen0.78, argon 0.1, CO2 is 0.000365, etc, all expressed as a number fraction,i.e. number of N2 divided by total number of air molecules. We like mixingratios to be expressed in numbers that are reasonable to write and easyto state, without all the zeros that follow the decimal place, as in thecase of CO2. So we multiply up the ratio by the factor of 1000 (a "mil"),10^6 (a "million"), 10^9 (a "billion"), or 10^12 (a "trillion"), and callthe result "parts per mil (or thousand)", "parts per million" (or ppm),"parts per billion" (or ppb), and "parts per trillion" (or ppt). So, forexample, CO2 is 365 ppm.
It's easy to get the number mixing ratio, whichwe call the "mixing ratio by volume". It's a little bit (not much, though)harder to get the "mass mixing ratio". For this, you have to convert thenumbers of molecules into mass, and then divide by the total mass of theair. The easiest way to do this is to multiply the mixing ratio by volume(assuming you have it already) by the molecular mass of the specie of interest(28 g/mole for N2, 32 g/mole for O2, 44 g,/mole for CO2, etc.) and divideby the molecular mass of air (28.8 g/mole, the weighted averages of themasses of the individual components of air). So the mass mixing ratio ofCO2 is 365 ppb x 44/28.8 = 558 ppm by mass.
4. I can't get the "meridional winds" plot to work. Help!
Try this:
[1] In the "visualize NCEP data" window selectthe button "no difference processing".
http://www.cdc.noaa.gov/cgi-bin/DataIntro.pl?dataset=NCEP
[2] In the subsequent window, select "meridionalwind" as your variable below, and click on the "monthly longterm mean"statistic link above. Click "continue image specification" box. Thisshould take you to a new window that will allow you to fill in the appropriate"blanks" to get the months you need.
[3] In the next window, for "dimension 1" pick"level" (this means altitude), and for "dimension 2" pick
"latitude". This should give you the next windowthat allows you to pick the plot limits.
[4] In the last window, leave the axis defaultsalone and pick longitude "0.0" an again on "357.5" (this will average overall longitudes, at least it did for me) and pick "JAN" and "JAN" in theother boxes (this will then only give January average). Click on the selectbutton, wait a minute or two, and voila...image! Myunderstanding of the way they are plotting this is that a negative wind("v" means in the N-S direction, not "vertical") is one that is a meanflow southward, and a positive number is a mean flow northward.
Please note that by averaging over all longitudes,you can only discuss "global" features, not individual regions, like California.To do a particular region, you will have to limit your averaging to a smallerrange of longitudes.
3. What is a "sounding diagram" and how do I read (construct) one?
4. Where can I find GOES realtime Images?
5. What is the molecular weight of "X"?
The PeriodicTable of the Elements
6. What does "^&$(#*" mean?
