考虑β随纬度变化下的Rossby孤立波与偶极子阻塞

利用文献[4]得到的推广的β平面近似式为f=f0+β0 y—（δ0/2）y2,研究由δ0项所引起的一类Rossby孤立波，而不考虑基流切变和地形等因子的作用。经过计算可以发现，当经向波数为1时，这种孤立波具有显著的南低北高的偶极子阻塞结构，它主要存在于弱西风气流中，并且偶极子的能量随着纬度的增高更容易集中(即高纬偶极子结构趋于局地化)，因而，β随纬度的变化可能是中高纬度地区偶极子阻塞产生的原因之一。

Solitary Rossby Waves with the Beta Parameter and Dipole Blocking

Using a generalized beta-plane approximation f =fo+βoy －(δ0 /2)y2 , a kind of the solitary Rossby waves excited by theδ0 term excluding effects of shearing basic flow and topography et al is mainly investigated. The computational results show that the obtained solitary Rossby wave with meridional wavenumber 1 has a dipole structure with a high pressure in the north and a low in the south, which mainly exists in the weak westerly wind. On the other hand, the energy of dipole easily accumulates with the latitude. Thus, the beta parameter with the change of latitude may be one reason of producing dipole blocking in the mid-high latitudes.