利用各向同性和非各向同性两种GRACE时变重力场平滑方法试算了2006年1月至2月的全球大地水准面变化。研究表明,非各向同性的高斯滤波器的频谱不仅依赖于阶也依赖于次,但能够提高纬度方向的分辨率,在经度方向的分辨率和各向同性滤波器的相当;计算得到了与各向同性高斯平滑同精度的时变重力场反演结果。
Two methods isotropic Gaussian filter and non-isotropic Gaussian filter of GRACE temporal gravity variation smoothing, and their properties are studied. With these methods, the global geoid change between January and February 2006 was computed. The results show that non-isotropic Gaussian filter' s spectrum depends not only on degree but also on order; the non-isotropic smoother yields enhanced GRACE signals with significantly higher spatial resolution in latitude and the same resolution in longitude without reducing the accuracy as compared to isotropic Gaussian filter.