重力卫星GRACE Mascon产品的应用研究进展与展望

Progress and prospect of GRACE Mascon product and its application

2002年重力卫星GRACE的成功发射极大地促进了地球科学多个领域,包括全球海平面变化、极地冰盖与高山冰川消融、水文以及固体地球等多个领域的发展.然而,GRACE观测数据主要是以球谐系数的形式给出,需要应用者进行一系列预处理才可以得到对应的物理量.为了克服此困难,也为了提高GRACE恢复重力场地空间分辨率,相关机构在近些年推出了新一代GRACE观测数据产品,即Mascon产品.该产品的初衷是便于非大地测量和地球物理专业的人使用,比如水文学家、海洋学家,它无需进行任何后处理过程,使用上更加方便.然而,尽管Mascon产品以较高的空间分辨率(如1°)给出,但是,该产品的应用范围以及其实际的分辨率等都是科学家们非常关注的问题.目前科学家们已经对该产品在不同流域尺度以及不同应用领域上的适用性问题进行了系统性地评估.本文综合介绍了Mascon产品的基本原理和方法、三家Mascon产品的差异,并梳理了该产品和球谐系数产品之间在一些具体物理问题的应用中的适用性以及应该注意的问题,为广大科研工作者提供科学依据和使用参考.

The success of the launch of GRACE in 2002 has greatly promoted the development of Earth Sci-ence,especially in many fields such as global sea level change,polar ice sheet and Alpine glacier melting,hydro-logy and solid earth.However,GRACE observation data are mainly given in the form of spherical harmonic coeffi-cients,so users need to carry out a series of pre-processing to get specific physical quantities.In order to overcome this difficulty and enhance the spatial resolution,relevant organizations have released a new generation of GRACE products,named Mascon products.The original intention of this product is to be convenient for people who are not majoring in Geodesy and Geophysics,such as hydrologists and oceanographers,and it does not need any post-pro-cessing process,so it is more convenient to use.Although Mascon product gives a high spatial resolution(such as 1°),scientists are very concerned about the actual resolution and the application scope of the product.At present,scientists have systematically evaluated and applied the applicability of this product in different watershed scales and different application fields.In this paper,we introduce the basic principles and methods of Mascon products,compa-res the differences between the three Mascon products,and combs the applicability of the products and spherical har-monic coefficient products in the application of some specific physical problems as well as the problems that should be paid attention to,so as to provide scientific basis and use reference for the majority of scientific researchers.