On the Energetics of Horizontal Lability (2)

[摘要] In the present report the author calculates the energy releasable from horizontally unstable situations of a wet atmosphere, a sequel to his last paper in which those of a dry atmosphere were treated of, and a modification of the former conclusion in view of the wet adiabatic upward motion of moist air is introduced.Consider the ini_??_al state of the cold and the saturated warm masses lying side by side. In the final state the cold mass descends dry-adiabatically over the ground and the warm mass ascends over it wet-adiabatically.Two cases occur according as either the lapserate a is larger or smaller than the wet adiabatic lapse-rate γm. In the former case the entropy decreases upwards and the stratification of ascending mass becomes inverse, therefore the upper half of the warm mass should descend dry-adiabatically and the wet adiabatic motion is possible only in the lower half. In the latter case the whole warm mass ascends, wet-adiabatically with the same stratification.Margules already treated a similar problem in his famous paper on the energy of storm, assuming the dry adiabatic lapse-rate _??_ in the cold mass and the wet adiabatic lapse-rate in the warm mass, which corresponds to the case of no latent instability as pointed out by Normand.The energy equation has been derived, assuming the constancy of wet adiabatic lapse-rate and putting γm=1/2_??_. The result of numerical evaluation is as follows: horizontal difference of temperature: 10°C.It is noticeable here that, in case of γm

[学科分类] 大气科学