Talk:NRLMSISE-00

Latest comment: 5 years ago by Prevalence in topic Logarithmic scale graph

== This is a pretty immemorable reference! Is it meant to entirely supersede the International Standard Atmosphere of 1976? Linuxlad 15:37, 9 May 2006 (UTC)Reply

Distribution

edit

In the source paper, distribution is described thus : "The present NRLMSISE-00 distribution package is an ASCII file containing the model source, a test driver, and the expected output of the test driver. Users may acquire the file via two methods: (1) download from our website (http://uap-www.nrl.navy.mil/models_web/msis/msis_home.htm); (2) send e-mail to NRLMSISE-00@uap2.nrl.navy.mil (no subject or message), which will result in a reply with the file as an attachment."

At this time (see signature), the website is not responding. A related (?) site https://www.nrl.navy.mil/ppd/sites/www.nrl.navy.mil.ppd/files/source_code/nrlmsise00.f does return what looks like relevant FORTRAN code, but assessing if this is actually the required data is beyond my very old FORTRAN skills.

AKarley (talk) 00:02, 2 March 2019 (UTC)Reply

Logarithmic scale graph

edit

The minor horizontal grid lines in the graph make little sense. It's a log scale, so you use a geometric sequence for the major gridlines (like 1, 10, 100, 1000, or in this case 10-3 10-6, 10-9...), but linear sequences for the minor gridlines between them (for example 8 minor gridlines between 1 and 10, at 2, 3, 4, 5, 6, 7, 8 and 9). Here, the major grid increases with a factor 1000. But what about the minor grid? It's obviously not geometric (since it isn't equidistant). And it isn't a linear sequence, since that would be (1, 112, 223, 334 .. 889, 1000). The first segment would be 2/3 of the total distance. So what is it? The distances seem to correspond to log 2, log 3, log 4 ... log 10. So these are the minor gridlines meant for a major grid that increases with a factor 10. With a factor 1000, those gridlines don't correspond to values 2 to 9 or 200 to 900, but to values 23 to 93 (8, 27, 64, 125, 216, 343, 512, 729). A grid is meant to make it easy to read the approximate coordinates of a point on the graph. Here, only the major gridlines are helpful. Prevalence 11:46, 20 March 2019 (UTC)Reply