孤立子型热源强迫与大气和海洋流场的奇异响应

运用非线性动力学分析方法,对一个广义的地球流体动力学正压准地转模式中,局地热源强迫对大气和海洋流场产生的响应结果,进行了解析研究.发现热源扰动和响应流场之间存在很好的对应关系:两者具有类似的分布模态,且孤立子型的响应流场要比孤立子型的热源强迫范围大得多,即"狭窄"的热源扰动可能导致"宽广"的流场响应;强迫热源的特殊结构有可能导致大气或海洋流场出现奇异响应,从而使大气或海洋环流发生异常(如大气阻塞现象);中、高纬地区的大气和海洋流场对热源强迫的响应要比低纬地区显著得多.上述结果与中、低纬大气试验和观测资料的研究结果相符,可部分解释地球流体中,局地热源异常可能导致的环流异常现象.

Soliton-Like Thermal Source Forcing and Singular Response of Atmosphere and Oceans to It

Non-linear dynamic study is undertaken of the response of atmospheric and oceanic flow fields to local thermal source forcing in the context of a generalized geophysical fluid dynamic barotropic quasi-geostrophic model, discovering a good relation between thermal disturbance and flow field response to it, both having similar modes, and that the soliton-like responding field is a great deal larger in extent than the analogous-form forcing field, which implies that a "narrow" thermal disturbance can excite a "wide" response field, in some cases the particular structure of a thermal source may give rise to singular response of atmospheric and oceanic flow fields, thus displaying their abnormalities(for example the blocking situation in the atmosphere), the atmospheric and oceanic stream fields at mid-high latitudes respond to thermal forcing in a much more pronounced manner compared to those at low latitudes. The said research results that is in agreement with studies from mid-low latitude atmospheric experiments and observations and can be used to partially interpret the circulation singularity due to heat source anomaly on a local basis in the context of earch fluid flows.