The following is the list of a(n) and b(n) coefficients defining the model levels, accompanied by the corresponding half-level, ph, and full-level, pf, values of pressure for a surface pressure of 1013.250 hPa. Also provided are the Geopotential and Geometric heights, the temperature and density of the level based on the 1976 version of the International Civil Aviation Organization (ICAO) Standard Atmosphere as described at:
- U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C., 1976(PDF - 76Mbytes)
- WikiPedia entry for International Standard Atmosphere
A description of how model levels should be interpreted is available in the IFS documentation Part III- chapter 2 (DISCRETISATION --> Vertical discretisation)
n | a [Pa] | b | ph [hPa] | pf [hPa] | Geopotential Altitude [m] | Geometric Altitude [m] | Temperature [K] | Density [kg/m^3] |
---|---|---|---|---|---|---|---|---|
0 | 0.000000 | 0.000000 | 0.000000 | - | - | - | - | - |
1 | 20.000000 | 0.000000 | 0.2000 | 0.1000 | 64947.31 | 65616.42 | 231.60 | 0.000150 |
2 | 38.425343 | 0.000000 | 0.3843 | 0.2921 | 57350.89 | 57872.01 | 252.87 | 0.000402 |
3 | 63.647804 | 0.000000 | 0.6365 | 0.5104 | 53125.16 | 53572.02 | 264.70 | 0.000672 |
4 | 95.636963 | 0.000000 | 0.9564 | 0.7964 | 49623.45 | 50013.12 | 270.65 | 0.001025 |
5 | 134.483307 | 0.000000 | 1.3448 | 1.1506 | 46709.58 | 47054.67 | 269.84 | 0.001485 |
6 | 180.584351 | 0.000000 | 1.8058 | 1.5753 | 44259.61 | 44569.33 | 262.98 | 0.002087 |
7 | 234.779053 | 0.000000 | 2.3478 | 2.0768 | 42156.09 | 42436.98 | 257.09 | 0.002814 |
8 | 298.495789 | 0.000000 | 2.9850 | 2.6664 | 40294.73 | 40551.28 | 251.88 | 0.003688 |
9 | 373.971924 | 0.000000 | 3.7397 | 3.3623 | 38600.97 | 38836.35 | 247.13 | 0.004740 |
10 | 464.618134 | 0.000000 | 4.6462 | 4.1930 | 37018.28 | 37234.70 | 242.70 | 0.006018 |
11 | 575.651001 | 0.000000 | 5.7565 | 5.2013 | 35500.64 | 35699.63 | 238.45 | 0.007599 |
12 | 713.218079 | 0.000000 | 7.1322 | 6.4443 | 34017.99 | 34200.66 | 234.30 | 0.009582 |
13 | 883.660522 | 0.000000 | 8.8366 | 7.9844 | 32561.15 | 32728.48 | 230.22 | 0.012082 |
14 | 1094.834717 | 0.000000 | 10.9483 | 9.8925 | 31127.02 | 31279.89 | 227.78 | 0.015130 |
15 | 1356.474609 | 0.000000 | 13.5647 | 12.2565 | 29702.74 | 29841.91 | 226.35 | 0.018863 |
16 | 1680.640259 | 0.000000 | 16.8064 | 15.1856 | 28287.36 | 28413.56 | 224.94 | 0.023518 |
17 | 2082.273926 | 0.000000 | 20.8227 | 18.8146 | 26880.84 | 26994.77 | 223.53 | 0.029322 |
18 | 2579.888672 | 0.000000 | 25.7989 | 23.3108 | 25483.11 | 25585.48 | 222.13 | 0.036557 |
19 | 3196.421631 | 0.000000 | 31.9642 | 28.8816 | 24094.12 | 24185.62 | 220.74 | 0.045579 |
20 | 3960.291504 | 0.000000 | 39.6029 | 35.7836 | 22713.82 | 22795.11 | 219.36 | 0.056826 |
21 | 4906.708496 | 0.000000 | 49.0671 | 44.3350 | 21342.15 | 21413.91 | 217.99 | 0.070849 |
22 | 6018.019531 | 0.000000 | 60.1802 | 54.6236 | 20014.52 | 20077.62 | 216.66 | 0.087826 |
23 | 7306.631348 | 0.000000 | 73.0663 | 66.6233 | 18755.37 | 18810.77 | 216.65 | 0.107127 |
24 | 8765.053711 | 0.000076 | 87.7274 | 80.3968 | 17563.62 | 17612.18 | 216.65 | 0.129274 |
25 | 10376.126953 | 0.000461 | 104.2288 | 95.9781 | 16440.20 | 16482.75 | 216.65 | 0.154328 |
26 | 12077.446289 | 0.001815 | 122.6137 | 113.4212 | 15381.19 | 15418.43 | 216.65 | 0.182375 |
27 | 13775.325195 | 0.005081 | 142.9017 | 132.7577 | 14382.89 | 14415.44 | 216.65 | 0.213467 |
28 | 15379.805664 | 0.011143 | 165.0886 | 153.9952 | 13441.79 | 13470.22 | 216.65 | 0.247616 |
29 | 16819.474609 | 0.020678 | 189.1466 | 177.1176 | 12554.62 | 12579.42 | 216.65 | 0.284796 |
30 | 18045.183594 | 0.034121 | 215.0251 | 202.0859 | 11718.27 | 11739.87 | 216.65 | 0.324943 |
31 | 19027.695313 | 0.051690 | 242.6523 | 228.8387 | 10930.02 | 10948.81 | 217.10 | 0.367189 |
32 | 19755.109375 | 0.073534 | 272.0593 | 257.3558 | 10175.26 | 10191.54 | 222.01 | 0.403822 |
33 | 20222.205078 | 0.099675 | 303.2174 | 287.6383 | 9444.61 | 9458.63 | 226.76 | 0.441886 |
34 | 20429.863281 | 0.130023 | 336.0439 | 319.6307 | 8737.51 | 8749.51 | 231.36 | 0.481280 |
35 | 20384.480469 | 0.164384 | 370.4072 | 353.2256 | 8054.20 | 8064.40 | 235.80 | 0.521847 |
36 | 20097.402344 | 0.202476 | 406.1328 | 388.2700 | 7395.38 | 7403.97 | 240.08 | 0.563389 |
37 | 19584.330078 | 0.243933 | 443.0086 | 424.5707 | 6761.89 | 6769.08 | 244.20 | 0.605674 |
38 | 18864.750000 | 0.288323 | 480.7907 | 461.8996 | 6154.67 | 6160.62 | 248.14 | 0.648445 |
39 | 17961.357422 | 0.335155 | 519.2093 | 500.0000 | 5574.58 | 5579.46 | 251.92 | 0.691426 |
40 | 16899.468750 | 0.383892 | 557.9734 | 538.5913 | 5022.43 | 5026.39 | 255.50 | 0.734331 |
41 | 15706.447266 | 0.433963 | 596.7774 | 577.3754 | 4498.91 | 4502.09 | 258.91 | 0.776863 |
42 | 14411.124023 | 0.484772 | 635.3060 | 616.0417 | 4004.59 | 4007.11 | 262.12 | 0.818729 |
43 | 13043.218750 | 0.535710 | 673.2403 | 654.2732 | 3539.96 | 3541.93 | 265.14 | 0.859634 |
44 | 11632.758789 | 0.586168 | 710.2627 | 691.7515 | 3105.35 | 3106.86 | 267.97 | 0.899295 |
45 | 10209.500977 | 0.635547 | 746.0635 | 728.1631 | 2701.00 | 2702.14 | 270.59 | 0.937436 |
46 | 8802.356445 | 0.683269 | 780.3455 | 763.2045 | 2327.04 | 2327.89 | 273.02 | 0.973801 |
47 | 7438.803223 | 0.728786 | 812.8303 | 796.5879 | 1983.49 | 1984.11 | 275.26 | 1.008150 |
48 | 6144.314941 | 0.771597 | 843.2634 | 828.0468 | 1670.26 | 1670.70 | 277.29 | 1.040270 |
49 | 4941.778320 | 0.811253 | 871.4203 | 857.3419 | 1387.12 | 1387.43 | 279.13 | 1.069971 |
50 | 3850.913330 | 0.847375 | 897.1118 | 884.2660 | 1133.73 | 1133.93 | 280.78 | 1.097099 |
51 | 2887.696533 | 0.879657 | 920.1893 | 908.6505 | 909.57 | 909.70 | 282.24 | 1.121533 |
52 | 2063.779785 | 0.907884 | 940.5511 | 930.3702 | 713.97 | 714.05 | 283.51 | 1.143192 |
53 | 1385.912598 | 0.931940 | 958.1477 | 949.3494 | 546.06 | 546.11 | 284.60 | 1.162039 |
54 | 855.361755 | 0.951822 | 972.9868 | 965.5672 | 404.72 | 404.74 | 285.52 | 1.178087 |
55 | 467.333588 | 0.967645 | 985.1399 | 979.0633 | 288.55 | 288.57 | 286.27 | 1.191403 |
56 | 210.393890 | 0.979663 | 994.7472 | 989.9435 | 195.85 | 195.85 | 286.88 | 1.202112 |
57 | 65.889244 | 0.988270 | 1002.0236 | 998.3854 | 124.48 | 124.48 | 287.34 | 1.210406 |
58 | 7.367743 | 0.994019 | 1007.2639 | 1004.6437 | 71.89 | 71.89 | 287.68 | 1.216546 |
59 | 0.000000 | 0.997630 | 1010.8487 | 1009.0563 | 34.97 | 34.97 | 287.92 | 1.220871 |
60 | 0.000000 | 1.000000 | 1013.2500 | 1012.0494 | 10.00 | 10.00 | 288.09 | 1.223803 |
Click on the Export link to save this table as a CSV file.
Export..