COSPAR International Reference Atmosphere (CIRA) 1986 ----------------------------------------------------- This directory includes two versions of the CIRA 1986 model of the Committee on Space Research (COSPAR): /cira86/ The original version as provided by E. Fleming (Nov 1989) in binary form including also a simple Fortran program written at NSSDC to read the binary data files. /cira86ascii/ A slightly modified version provided by J. Barnett (July 1990) in ASCII format. ----------------------------------------- ERRORS and INCONSISTENCIES noted by users ----------------------------------------- ================================================================================== Date: Mon, 22 Nov 1999 12:32:06 -0700 From: "Justin C Dyster" To: Bilitza@ndadsb-f.gsfc.nasa.gov cc: "Victor J Wagner at 5-840136-TU" , "Donald H Coleman at 5-805161-TU" Subject: COSPAR 1986 Sir, As per our telephone conversation on 22 November 1999 I am sending you this e-mail in reference to the COSPAR International Reference Atmosphere 1986, 0 - 120 km. I was examining the pressures at the 60 km (200,000 ft., any month, at 30N latitude) when I noticed that they varied by approximately a factor of 10 from the US Standard Atmosphere, 1976 table at the same altitude. In addition at any month as your altitude increases the pressure varies irregular It rises and drops suddenly at specific altitudes. If someone could please give me some explanation to these issues I would greatly appreciate it. Sincerely, Justin Dyster Raytheon Electronic Systems System Engineering LEAP Tucson, AZ 85734 Phone: (520) 794-8226 E-Mail: jcdyster@west.raytheon.com ================================================================================== Date: Wed, 24 Oct 2001 09:55:05 +0200 From: Francis.Dalaudier@aerov.jussieu.fr (Dalaudier francis) Subject: Found errors in CIRA ascii files ? Cc: chandra@chapman.gsfc.nasa.gov, Anabelle.Menochet@tornado.badc.rl.ac.uk Dear colleague, while using the CIRA ascii files found at http://www.badc.rl.ac.uk/cgi-bin/data_browser/data_browser/badc/cira/data [same as ftp://nssdcftp.gsfc.nasa.gov/models/atmospheric/cira/cira86ascii/] I found what look very much like an error... I was initially rather surprised, since I believed that the CIRA model was now completely "debugged" after nearly 15 years of worldwide usage. However, after cross checking my sources, I found that the error is even present in the original publication : CIRA 1986, Part II Middle Atmosphere Models, D. Rees, J.J. Barnett, K. Labitzke (ed.), Advances in Space Research (COSPAR), Volume 10, Number 12, 1990. on pages (12)400 - (12)401 and (12)454 the error on page (12)454 is benign : The last 5 lines from file shant.lsn Height (mb) Height 80S 75S 70S 65S 60S 55S ... 1.00 372.66 8.0 3.4 3.8 3.9 4.0 3.8 2.5 ... 0.75 478.51 6.1 3.4 4.0 4.2 4.2 4.3 2.6 ... 0.50 614.42 4.2 3.1 4.1 4.3 4.3 4.1 3.1 ... 0.25 788.93 2.2 3.6 3.6 3.6 3.9 3.8 3.3 ... 0.00 1013.0 0.1 3.6 3.6 3.6 1.3 1.7 2.0 ... should read : (undefined values set to blank) 1.00 372.66 8.0 3.4 3.8 3.9 4.0 3.8 2.5 ... 0.75 478.51 6.1 3.4 4.0 4.2 4.2 4.3 2.6 ... 0.50 614.42 4.2 3.1 4.1 4.3 4.3 4.1 3.1 ... 0.25 788.93 2.2 3.9 3.8 3.3 ... 0.00 1013.0 0.1 1.3 1.7 2.0 ... However, the error on pages (12)400 - (12)401 is more serious ! If you consider the files nhz.lsn ans shz.lsn, and write down all the lines corresponding to 0.00 Scale Height (last line each month), it is obvious that the "ground" geopotential for OCTOBER is WRONG. The "OCTOBER" line is obviously flawed with respect to other monthes. You can look a sample at the end of this message. A graphical representation is even more dramatic ! This error propagate also upward (in October only) and can still be visually detected up to 1.25 scale height (6 lines of data). It seems that one (or a few) wrong data were used in calculation of geopotential height. I was not able to detect similar problems on other files (temperature, wind, pressure). Nevertheless, it may be judicious to check also the other data files. Thank you. Best regards Francis Dalaudier ___________________________________________________________________ >From nhz.lsn Scale Pressure Height (mb) 0 ... 60N 65N 70N 75N 80N 0.00 1013.0 -30 ... -21 -6 14 20 11 0.00 1013.0 -32 ... -19 -5 18 35 46 0.00 1013.0 -31 ... -11 -8 21 36 31 0.00 1013.0 -29 ... 1 11 24 37 49 0.00 1013.0 -26 ... 8 15 25 30 30 0.00 1013.0 -19 ... -13 -15 -11 -9 -11 0.00 1013.0 -18 ... -11 -18 -14 -9 -5 0.00 1013.0 -17 ... -17 -15 -11 -7 -2 0.00 1013.0 -17 ... -22 -22 -10 -4 -5 # 0.00 1013.0 271 ... -162 -225 -277 -321 -355 #OCTOBER 0.00 1013.0 -25 ... -26 -22 -9 -1 1 0.00 1013.0 -30 ... -23 -19 -6 2 5 >From shz.lsn Scale Pressure Height (mb) 80S ... 20S 15S 10S 5S 0 0.00 1013.0 999 ... -6 -20 -28 -30 -30 0.00 1013.0 999 ... -10 -23 -30 -32 -32 0.00 1013.0 999 ... -1 -17 -26 -30 -31 0.00 1013.0 999 ... 6 -9 -21 -28 -29 0.00 1013.0 999 ... 17 -1 -15 -23 -26 0.00 1013.0 999 ... 33 12 -5 -15 -19 0.00 1013.0 999 ... 40 15 -3 -13 -18 0.00 1013.0 999 ... 42 18 0 -11 -17 0.00 1013.0 999 ... 34 14 -2 -11 -17 # 0.00 1013.0 999 ... 256 266 269 269 271 #OCTOBER 0.00 1013.0 999 ... 13 -3 -14 -22 -25 0.00 1013.0 999 ... 2 -13 -24 -29 -30 ___________________________________________________________________ ________________________________________________________________________ | Francis Dalaudier |tel: 33 1 64 47 42 11 | | Service d'Aéronomie du CNRS |fax: 33 1 69 20 29 99 | | BP 3 |e-mail : | | 91371 VERRIERES-LE-BUISSON CEDEX | francis.dalaudier@aerov.jussieu.fr | | FRANCE | | |__________________________________|_____________________________________| ================================================================================== Date: Thu, 22 Nov 2001 18:05:38 +0100 (CET) From: "STEINER Rene'" Sender: To: Subject: CIRA-86 Dear Dieter, I've found a non-consistency between your electronic version of CIRA-86 and the one contained in Rees, D., J.J. Barnett and K. Labitzke: CIRA: 1986, Part II: Middle Atmosphere Models. As far as I could trace the differences, they appear only in the height region 75 to 90 km. For example, let's take a look at: ftp://nssdcftp.gsfc.nasa.gov/models/atmospheric/cira/cira86ascii/twp.lsn and page 430 of the book: At 80°S, twp.lsn says 200.7, 172.4, 145.7 and 139.1 for 75, 80, 85 and 90 km, respectively. The file, however, says 200.1, 171.7, 147.9 and 142.9. As I couldn't find any remark that the model has been updated since, I'd like to know whether the discrepancies are due to a mistake or due to some new data. Best regards, Rene' -- Rene' STEINER steiner@ieee.org www.sbox.TUGraz.at/home/s/steiner Space Research Institute Austrian Academy of Sciences ==================================================================================