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Key atmospheric-related constants, defined for the earth.
Class attributes:
* epsilon: Ratio of gas constant for dry air to gas constant
for water vapor [unitless].
* g: Gravitational constant [m/s**2]. Set to g_wmo.
* g_approx: Approximate value of gravitational constant [m/s**2].
This value is commonly used in rough calculations.
* g_rean: Gravitational constant [m/s**2] used in most calcula-
tions in the NCEP/NCAR reanalysis. See the FAQ for details:
http://dss.ucar.edu/pub/reanalysis/FAQ.html.
* g_wmo: Gravitational constant [m/s**2] used by the WMO to cali-
brate barometers.
* Gamma_d: Dry adiabatic lapse rate [K/m].
* R_d: Gas constant for dry air [J/(K kg)].
* R_univ: Universal gas constant [J/(mol kg)].
* R_v: Gas constant for water vapor [J/(K kg)].
* c_p: Specific heat at constant pressure for dry air [J/(K kg)].
* C2K_add_offset: Value to add to degrees Centigrade to convert
to Kelvin. 0 deg C is defined to be at the ice point, which is
273.15 K. Note the triple point and ice point are different.
In Kelvin, the fundamental reference point is the triple point,
which equals 273.16. See Weast (p. F-73, 90) for details.
* ice_point: The ice point of water [K].
* kappa: Ratio R_d to c_p [unitless].
* triple_point: The triple point of water [K].
This class accepts no arguments and has no methods.
References:
* Glickman, T. S. (Ed.) (2000): Glossary of Meterology. Boston,
MA: American Meteorology Society, 855 pp.
* Peixoto, J. P., and A. H. Oort (1992): Physics of Climate.
New York, NY: American Institute of Physics, ISBN 0-88318-711-6,
520 pp.
* Shea, D. J., S. J. Worley, I. R. Stern, and T. J. Hoar (1995,
2003): An Introduction to Atmospheric and Oceanographic Datasets,
NCAR Technical Note NCAR/TN-404+IA. Boulder, CO: NCAR. Web
copy: http://www.cgd.ucar.edu/cas/tn404/.
* Weast, R. C. (Ed.) (1987): CRC Handbook of Chemistry and Physics
(68th Edition). Boca Raton, FL: CRC Press, Inc.
* Wallace, J. M., and P. V. Hobbs (1977): Atmospheric Science:
An Introductory Survey. San Diego, CA: Academic Press, ISBN
0-12-732950-1, 467 pp.
Examples:
>>> from atmconst import AtmConst
>>> const = AtmConst()
>>> const.R_d
287.05000000000001
>>> const.g
9.8066499999999994 |