By analyzing the correlation between the occurrence area of grasshopper and 74 characteristic indexes of atmospheric circulation in western Aletai from 1991 to 2008,the atmospheric circulation factors which had the si...By analyzing the correlation between the occurrence area of grasshopper and 74 characteristic indexes of atmospheric circulation in western Aletai from 1991 to 2008,the atmospheric circulation factors which had the significant relationship with the occurrence area of grasshopper in different counties were screened.The prediction models for the occurrence area of grasshopper in different counties were established by stepwise regression method,and the models obtained were also tested.These models were subsequently utilized to carry out extended prediction on the occurrence area of grasshopper in different counties of western Aletai from 2009 to 2010.Meanwhile,the relationship between the atmospheric circulation factors and the occurrence area of grasshopper were analyzed.The results provided the theoretical basis for the prediction on grasshopper plague.展开更多
By using a low-order,two-layer baroclinic quasi-geostrophic model,a nonlinear system including the interaction between a thermal forced wave,a transient wave and zonal flow is studied. Under the conditions of near-res...By using a low-order,two-layer baroclinic quasi-geostrophic model,a nonlinear system including the interaction between a thermal forced wave,a transient wave and zonal flow is studied. Under the conditions of near-resonance and weak baroclinic instability,the features of solution in phase space are discussed with the analytical methods of multiple scale and discontinuous oscillation.The results show that the dynamic coupling between forced wave and transient wave is responsible for the physical mechanism of the non-uniform index cycle of the atmospheric circulation.展开更多
基金Supported by Youth Fund Project of Meteorological Bureau in Xinjiang Uygur Autonomous Region(201040)~~
文摘By analyzing the correlation between the occurrence area of grasshopper and 74 characteristic indexes of atmospheric circulation in western Aletai from 1991 to 2008,the atmospheric circulation factors which had the significant relationship with the occurrence area of grasshopper in different counties were screened.The prediction models for the occurrence area of grasshopper in different counties were established by stepwise regression method,and the models obtained were also tested.These models were subsequently utilized to carry out extended prediction on the occurrence area of grasshopper in different counties of western Aletai from 2009 to 2010.Meanwhile,the relationship between the atmospheric circulation factors and the occurrence area of grasshopper were analyzed.The results provided the theoretical basis for the prediction on grasshopper plague.
文摘By using a low-order,two-layer baroclinic quasi-geostrophic model,a nonlinear system including the interaction between a thermal forced wave,a transient wave and zonal flow is studied. Under the conditions of near-resonance and weak baroclinic instability,the features of solution in phase space are discussed with the analytical methods of multiple scale and discontinuous oscillation.The results show that the dynamic coupling between forced wave and transient wave is responsible for the physical mechanism of the non-uniform index cycle of the atmospheric circulation.
