Ice velocity constitutes a key parameter for quantifying ice-sheet discharge rates and is thus crucial for improving the coupled models of the Antarctic ice sheet towards accurately predict its contribution to future ...Ice velocity constitutes a key parameter for quantifying ice-sheet discharge rates and is thus crucial for improving the coupled models of the Antarctic ice sheet towards accurately predict its contribution to future global sea-level rise.However,in Antarctica,high-resolution and continuous ice velocity estimates remain elusive,which is key to unravel Antarctica’s present-day ice mass balance processes.Here,we present a suite of newly estimated Antarctic-wide,annually-sampled ice velocity products at 105-m grid-spacing observed by Landsat 8 optical images data.We first describe a procedure that can automatically calibrate and integrate ice displacement maps to generate Antarcticwide seamless ice velocity products.The annual ice velocity mosaics are assembled using a total of 250,000 displacement maps inferred from more than 80,000 Landsat 8 images acquired between December 2013 and April 2019.The new annual Antarctic ice velocity data product exhibits an improved quantification of near-decadal Antarctic-wide ice flow,and an opportunity to investigate ice dynamics at a higher spatial resolution and annual sampling,as compared to existing data products.Validation studies confirmed improved accuracy and consistency of this new data product,when compared with independently estimated optical and radar ice velocity data products,as well as in situ data.展开更多
基金supported by National Key R&D Program of China:[grant number 2017YFA0603103]the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(CAS):[grant number QYZDBSSWDQC027 and QYZDJ-SSW-DQC042]+1 种基金the National Natural Science Foundation of China:[grant number 41974009,41590854 and 41974040]Strategic Priority Research Program,CAS:[grant number XDA19070302 and XDA19070104].
文摘Ice velocity constitutes a key parameter for quantifying ice-sheet discharge rates and is thus crucial for improving the coupled models of the Antarctic ice sheet towards accurately predict its contribution to future global sea-level rise.However,in Antarctica,high-resolution and continuous ice velocity estimates remain elusive,which is key to unravel Antarctica’s present-day ice mass balance processes.Here,we present a suite of newly estimated Antarctic-wide,annually-sampled ice velocity products at 105-m grid-spacing observed by Landsat 8 optical images data.We first describe a procedure that can automatically calibrate and integrate ice displacement maps to generate Antarcticwide seamless ice velocity products.The annual ice velocity mosaics are assembled using a total of 250,000 displacement maps inferred from more than 80,000 Landsat 8 images acquired between December 2013 and April 2019.The new annual Antarctic ice velocity data product exhibits an improved quantification of near-decadal Antarctic-wide ice flow,and an opportunity to investigate ice dynamics at a higher spatial resolution and annual sampling,as compared to existing data products.Validation studies confirmed improved accuracy and consistency of this new data product,when compared with independently estimated optical and radar ice velocity data products,as well as in situ data.
