CAJ | 학술논문

大气Ekman层湍流系数的准确计算对数值天气预报和污染物扩散计算有着重要的意义.将集合计算和变分法结合起来,提出了目标泛函梯度计算的集合变分方案,并根据正演模式的线性化情况提出了两种计算流程.利用这种集合变分梯度算法及两种流程对Ekman层湍流系数进行了反演试验,结果表明这种算法实施简单、方便,根据观测资料能够比较准确地反演湍流系数值.
대기Ekman층단류계수적준학계산대수치천기예보화오염물확산계산유착중요적의의.장집합계산화변분법결합기래,제출료목표범함제도계산적집합변분방안,병근거정연모식적선성화정황제출료량충계산류정.이용저충집합변분제도산법급량충류정대Ekman층단류계수진행료반연시험,결과표명저충산법실시간단、방편,근거관측자료능구비교준학지반연단류계수치.
The accurate value of the turbulent coefficient in Ekman layer of atmosphere is quite important for the numerical weather pre-diction and pollutant diffusion calculation. In the paper, based on ensemble method and variational method, the ensemble variational retrieval method is proposed, and the gradient of objective function is calculated with the method. Two calculation procedures are also given based on the linear condition of forward model. The inversion numerical experiments of the turbulent coefficient using ensemble variational method and two calculation flow process are carried out, and the results show that the method has the simple and convenient characteristics, and the turbulent coefficient can be retrieved accurately by observational data.