Structural changes in the currents and fields of the equatorial electrojet due to zonal and meridional winds
Structural changes in the currents and fields of the equatorial electrojet due to zonal and meridional winds
复制标题
DOI：
10.1029/ja092ia03p02514
复制
发表时间：
1987-03
影响因子：
--
通讯作者：
B. Anandarao;R. Raghavarao
中科院分区：
文献类型：
--
作者：
B. Anandarao;R. Raghavarao
根据观测特征，通过求解电动力学方程，计算了纬向风和经向风对赤道电喷流的影响。纬向风中的垂直切变可以引起2度以上电喷流的显著变化。在磁赤道，这些变化不到约10%。喷流的宽度(纬度)和厚度(高度)由这些剪切器改变多达100%。当宽度减小时，子午面内的电流密度强度增大。稳定的(不随海拔变化的)纬向风是无效的。将这些结果与前人的结果进行了比较。经向风引起相当大的越赤道电流，导致地面和火箭载磁力计推断的电喷流密度分布有相当大的不对称性。在100m/S的稳定北风作用下，电喷流中心向赤道以南约0.5度移动，经向风产生的电喷流电流的大小只有在偏离赤道的正负2度以上才显著偏离赤道。火箭载磁力计在赤道附近几度处观测到的东向电流密度垂直剖面中的结构可以用纬向风切变来解释。
The authors describe calculations of the effects of zonal and meridional winds on the equatorial electrojet vis-a-vis the observed features by solving the electrodynamic equations. Vertical shears in the zonal winds can cause significant changes in the electrojet beyond about 2{degree} latitude. At the magnetic equator these changes are less than about 10%. The width (latitudinal) and the thickness (altitudinal) of the jet are changed by as much as 100% by these shears. When the width is decreased, the intensity of the current densities in meridional plane is increased. Steady (not varying with altitude) zonal winds are ineffective. These results are discussed in comparison with those of earlier authors. Meridional winds cause substantial cross-equatorial currents leading to considerable asymmetry in the distribution of the electrojet current density as inferred by the ground-base and rocket-borne magnetometers. The electrojet center is shifted to about 0.5{degree} south of the equator by a steady northward wind of speed 100 m/s. The deviations in the magnitude of the electrojet current produced by the meridional winds are significant only beyond {plus minus}2{degree} off the equator. Structures in the vertical profiles of the eastward current density observed by rocket-borne magnetometers a few degrees off the equator canmore » be accounted for by the zonal wind shears.« less