CONVERSE TRENDS OF THE TERRESTRIAL AND GROUND WATER STORAGE CHANGES IN CANADA AND THE UNITED STATES

Raw DEMs are often misaligned with each other due to georeferencing errors, and a co-registration process is required before DEM differencing. We present a comparative analysis of the two classical DEM co-registration and three residual correction algorithms. The experimental results show that rotation and scale biases should be considered in DEM co-registration. The new non-parametric regression technique can eliminate the complex systematic errors, which existed in the co-registration results.

Thorough and continued monitoring of ice-sheet dynamics is of utmost importance for accurate predictions of ice-sheet behavior in the future. We present a new Antarctic ice velocity map at a 100-m grid spacing inferred from Landsat 8 imagery data. The datasets will allow for a comprehensive continent-wide investigation of ice dynamics and mass balance with the existing and future ice velocity measurements, provide control and calibration for ice-sheet modelling.

We constructed two present-day continent-wide ice flow maps on Antarctica, and estimated its mass balances over the last decade. An increased mass discharge from Wilkes Land, East Antarctica was found, contrary to the long-standing belief that accelerated mass loss primarily originates from West Antarctica and Antarctic Peninsula. Our maps allow the first continent-wide assessment of mass discharge changes in the last decade, which will contribute to our understanding of Antarctic ice dynamics.