一般通过在国界外围均匀添加一定数量的IGRF点以改善区域地磁场模型的边界效应.而最新的地磁场综合模型(Comprehensive Model 4,CM4)可以计算1960~2002年内全球任意区域的地核场、地壳场、磁层场及其感应场、电离层场及其感应场,其内...一般通过在国界外围均匀添加一定数量的IGRF点以改善区域地磁场模型的边界效应.而最新的地磁场综合模型(Comprehensive Model 4,CM4)可以计算1960~2002年内全球任意区域的地核场、地壳场、磁层场及其感应场、电离层场及其感应场,其内源场比IGRF更适合作为边界补充点以提高模型精度.本文对CM4和IGRF10的地核场网格图进行了比较,并以Taylor多项式模型为例,通过将34个CM4的内源场数据点和34个IGRF10的数值点分别作为边界补充点代入计算出网格值,并将其相减以分析差异.结果显示:各分量在国内大部分区域差异很小,几乎都为0值,在境外区域除了北向分量(X),其余分量均是正值,说明结合IGRF10建立的模型在国界外区域的数值偏小.展开更多
Observations show that the deep equatorial circulation is surprisingly energetic, with alternating eastward adn westward zonal currents(these fkows are commonly referred to as the deep equatorial jets) between 1 000 a...Observations show that the deep equatorial circulation is surprisingly energetic, with alternating eastward adn westward zonal currents(these fkows are commonly referred to as the deep equatorial jets) between 1 000 and 3 000 m. This paper shows that the waves generated by an off-equatorial deep buoyancy oscillation, and their energy radiatin as well as the equatorial focus of waves energy are the viable dynamic mechanisms of forming the deep equatorial jets.The results of testinh the effects of vertical mixing coefficients on the jets show that as the coefficients increase, the jets become weaker and their zonal coherent scales become longer.The solutions for different periods of forcing indicate that lengthening the period of forcing results in the position of the core of the deep jets moving westward and also enhances the zonal coherent scales of the jets.展开更多
文摘一般通过在国界外围均匀添加一定数量的IGRF点以改善区域地磁场模型的边界效应.而最新的地磁场综合模型(Comprehensive Model 4,CM4)可以计算1960~2002年内全球任意区域的地核场、地壳场、磁层场及其感应场、电离层场及其感应场,其内源场比IGRF更适合作为边界补充点以提高模型精度.本文对CM4和IGRF10的地核场网格图进行了比较,并以Taylor多项式模型为例,通过将34个CM4的内源场数据点和34个IGRF10的数值点分别作为边界补充点代入计算出网格值,并将其相减以分析差异.结果显示:各分量在国内大部分区域差异很小,几乎都为0值,在境外区域除了北向分量(X),其余分量均是正值,说明结合IGRF10建立的模型在国界外区域的数值偏小.
文摘Observations show that the deep equatorial circulation is surprisingly energetic, with alternating eastward adn westward zonal currents(these fkows are commonly referred to as the deep equatorial jets) between 1 000 and 3 000 m. This paper shows that the waves generated by an off-equatorial deep buoyancy oscillation, and their energy radiatin as well as the equatorial focus of waves energy are the viable dynamic mechanisms of forming the deep equatorial jets.The results of testinh the effects of vertical mixing coefficients on the jets show that as the coefficients increase, the jets become weaker and their zonal coherent scales become longer.The solutions for different periods of forcing indicate that lengthening the period of forcing results in the position of the core of the deep jets moving westward and also enhances the zonal coherent scales of the jets.