Global marine gravity anomalies recovered from multi-beam laser altime-ter data of ICESat-2
Satellite altimetry is one of the crucial techniques for the recovery of marine gravity anomalies.The along-track al-timeter data is commonly used,while the cross-track data from conventional altimetry missions is not used to recover marine gravity anomalies due to the long time intervals or sparse ground-track spacing,which limits the improvement of the gravity anomaly model.The ICESat-2 laser altimetry mission operates with three pairs of laser beams,each pair separated by 3 km,which provides the possibility of using the cross-track altimeter data.The cross-track data processing method is presented and global marine gravity anomaly models(named IS2Gra_alo and IS2Gra_alo_acr)are recovered from the along-track altimeter da-ta and the combination of along-track and cross-track altimeter data,respectively.The root mean square(RMS)of the differ-ence between IS2Gra_alo_acr and global shipborne gravity is 5.54 mGal,which is 0.16 mGal better than that of IS2Gra_alo.According to the difference between ICESat-2 gravity models and released global gravity anomaly models,the RMS derived by IS2Gra_alo_acr is at least 0.10 mGal better than that of IS2Gra_alo.The above results confirm that the accuracy of the gravity model recovered from along-track data is improved by incorporating cross-track data,and the ICESat-2 altimeter data is reliable for the recovery of global marine gravity anomalies.Additionally,the combination of different cross-track and along-track al-timeter data is discussed for the accuracy of the gravity model recovered from ICESat-2.The accuracy of the gravity model is able to be improved by incorporating the appropriate cross-track altimeter data with the along-track altimeter data.This re-search provides a reference for the recovery of marine gravity anomalies from the future altimeter data of the SWOT altimetry mission and the two-satellite tandem mode altimetry of China.
ICESat-2satellite laser altimetrymarine gravity anomalydeflection of the verticalsea surface height
万方数据
维普
