EFFECTS OF THE ENVELOPE DEGREE OF OROGRAPHY ON THE SIMULATED CLIMATE PROPERTIES^*

A primitive equation model with a zonal domain and a p-σ incorporated vertical coordinate system is used to study the effects of the envelope degree of orography on the simulated properties of both winter and summer climates.Results show that the orography with a larger envelope degree can improve the simulations to certain extent,especially in winter.It is found that the simulated properties of climate are mainly determined by the co-effects of the land-sea and the orographic distributions,and the envelope degree of orography has a secondary effect.However it should be taken properly in order to improve simulations:otherwise,it would be harmful.Different envelope degrees of orography can be adopted in different areas.