热带海洋对大气进行非绝热加热的随机效应的进一步研究

A FURTHER STUDY ON STOCHASTIC EFFECT ON THE ATMOSPHERE Of NON-ADIABATIC HEATING BY THETROPICAL OCEAN

摘要:

本文考虑了热带海洋对大气进行非绝热加热过程中海温起伏的随机效应,建立了朗之万方程形式的描写大气热量变化的发展方程。由该随机微分方程的定态解,给出了加热势函数和概率密度函数。在确定的热力学参数下,利用实际海温起伏方差值,计算求得了加热势函数的分布及概率密度分布曲线。文中还进一步计算了概率密度流,得到了在两种稳定状态之间穿透势垒的弛豫时间。计算结果表明,海温异常的随机效应是一个长周期过程,时间尺度约为140天,可以用实际测得的拖曳系数C_D和海温起伏方差q²值对它进行预测。

Abstract:

With the consideration of the stochastic effect of ocean surface temperature fluctuation (OSTF) during non-adiabatic heating of the atmosphere by the tropical ocean, an evolution epuation of Langevin type is established for the va-riation atmospheric heat. The steady-state solution of the random differential equation yields a heating potential function and probability density function. With a definite thermodynamical parameter, curves of the heating potential function and probability density distribution are obtained through the calculation of observed OSTF variances. Moreover, probability density stream is computed and relaxation time is derived for penetrating the potential castle between two steady states. Calculations indicate that the measured drag coefficient C_D and the OSTF variance q² can be used to predict the stochastic effect of anomalous ocean surface temperature, which has & duration of the order of 140 days.