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Wan, Xiaoyun (author), Ran, J. (author)The aim of this paper is to present an alternative method that can be used to improve existing gravity field models via the application of gradient data from Gravity field and Ocean Circulation Explorer (GOCE). First, the proposed algorithm used to construct the observation equation is presented. Then methods for noise processing in both time...journal article 2019
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Groh, Andreas (author), Horwath, Martin (author), Horvath, Alexander (author), Meister, Rakia (author), Wouters, B. (author), Ditmar, P.G. (author), Ran, J. (author), Klees, R. (author), Schrama, Ernst (author)Satellite gravimetry data acquired by the Gravity Recovery and Climate Experiment (GRACE) allows to derive the temporal evolution in ice mass for both the Antarctic Ice Sheet (AIS) and the Greenland Ice Sheet (GIS). Various algorithms have been used in a wide range of studies to generate Gravimetric Mass Balance (GMB) products. Results from...journal article 2019
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Ditmar, P.G. (author), Tangdamrongsub, N. (author), Ran, J. (author), Klees, R. (author)We propose a technique to regularize a GRACE-based mass-anomaly time-series in order to (i) quantify the Standard Deviation (SD) of random noise in the data, and (ii) reduce the level of that noise. The proposed regularization functional minimizes the Month-to-month Year-to-year Double Differences (MYDD) of mass anomalies. As such, it does...journal article 2018
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Ran, J. (author), Ditmar, P.G. (author), Klees, R. (author)The mascon approach is a well-known technique to estimate mass anomalies in Greenland using GRACE satellite gravity data. It partitions the area of interest into laterally-homogeneous patches (mascons). An important aspect of the mascon approach is the chosen geometry of mascons. So far, its impact has not been fully understood. In this study,...journal article 2018
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Ran, J. (author), Vizcaino, M. (author), Ditmar, P.G. (author), van den Broeke, Michiel R. (author), Moon, Twila (author), Steger, Christian (author), Enderlin, Ellyn (author), Wouters, Bert (author), Noël, Brice (author), Reijmer, Catharina (author), Klees, R. (author), Zhong, Min (author)The Greenland Ice Sheet (GrIS) is currently losing ice mass as the result of changes in the complex ice-climate interactions that have been driven by global climate change. In order to accurately predict future sea level rise, the mechanisms driving the observed mass loss must be better understood. Here, we combine data from the satellite...journal article 2018
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Ran, J. (author)The Greenland ice sheet (GrIS) is currently losing mass, as a result of complex mechanisms of ice-climate interaction that need to be understood for reliable projections of future sea level rise. The thesis focuses on the estimation of mass anomalies in Greenland using data from the GRACE satellite gravity mission. Monthly GRACE gravity field...doctoral thesis 2017
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Ran, J. (author), Ditmar, P.G. (author), Klees, R. (author), Farahani, H. (author)We present an improved mascon approach to transform monthly spherical harmonic solutions based on GRACE satellite data into mass anomaly estimates in Greenland. The GRACE-based spherical harmonic coefficients are used to synthesize gravity anomalies at satellite altitude, which are then inverted into mass anomalies per mascon. The limited...journal article 2017
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- Hashemifarahani, H. (author), Ditmar, P.G. (author), Inacio, P.M.G. (author), Klees, R. (author), Guo, J. (author), Guo, X. (author), Liu, X. (author), Zhao, Q. (author), Didova, O. (author), Ran, J. (author), Sun, Y. (author), Tangdamrongsub, N. (author), Gunter, B.C. (author), Riva, R.E.M. (author), Steele-Dunne, S.C. (author) conference paper 2014