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在前文[1]的基础上,进一步研究当海表温度存在经圈方向不均匀分布或偏离气候状态(距平)时,改变水分收支平衡及边界层的湿度辐合这一物理过程对Madden-Julian振荡的可能影响。结果表明,它对修正的Kelvin波和Rossby波的传播性质影响不大。但当海表温度为正距平时,修正后东传Kelvin波振幅不稳定增长到e倍的时间约减小了14.5%,其不稳定增长率随着热源特征宽度的增加而增加,当特征宽度为2倍Rossby变形半径时,不稳定增长率达极大,但当特征宽度继续增大时,其不稳定增长率又将减小。当海表温度为负距平时,修正后东传Kelvin波振幅不稳定增长到e倍的时间约增加20%,其不稳定增长率随着冷源特征宽度的增加而减小,当特征宽度为2倍Rossby变形半径时,其不稳定增长率达极小,此后;随着特征宽度的增加其不稳定增长率随之增加,但始终小于无海表温度异常的情形。经圈尺度较小的那支修正的Rossby波除波长极长的波段外,波仍是阻尼的;而经圈尺度较大的那支修正的Rossby波,在短的波段内仍是不稳定增长的。
On the basis of [1] above, we further study the effect of physical processes such as changing the water balance and the moisture convergence of the boundary layer, when the sea surface temperature has a non-uniform distribution in the ring direction or away from the climatic state (anomaly) -Julian possible effects of oscillation. The results show that it has little effect on the propagation properties of the modified Kelvin and Rossby waves. However, when the sea surface temperature is at an anomalous level, the time after the correction of the eastward-propagating Kelvin wave instability increases e-fold by about 14.5%, and its unstable growth rate increases with the increase of the width of the heat source. When the characteristic width is 2 times of the Rossby deformation radius, the unstable growth rate is extremely large, but its unstable growth rate will decrease when the width of the feature continues to increase. When the sea surface temperature is negative anomaly, the time of the echolocation of Kelvin wave amplitude increases about 20% after correction, and its unstable growth rate decreases with the increase of cold source feature width. When the characteristic width is When the radius of Rossby deformation is 2 times, the unstable growth rate is extremely small. After that, the unstable growth rate increases with the increase of characteristic width, but it is always lower than that without sea surface temperature anomaly. The modified Rossby wave with the smaller ring size is still damped except for the extremely long wavelength band. The modified Rossby wave with large ring size is still unstable in the short band .