@article{fdi:010091042,
  title = {{R}iver water level and water surface slope measurement from spaceborne radar and {L}i{DAR} altimetry : evaluation and implications for hydrological studies in the {G}anga {R}iver},
  author = {{D}hote, {P}. {R}. and {A}garwal, {A}. and {S}inghal, {G}. and {C}almant, {S}t{\'e}phane and {T}hakur, {P}. {K}. and {O}ubanas, {H}. and {P}aris, {A}. and {S}ingh, {R}. {P}.},
  editor = {},
  language = {{ENG}},
  abstract = {{S}atellite altimetry has revolutionized river monitoring, particularly for hydrologists working on river flow monitoring in sparsely or ungauged areas. {D}espite this, there is a lack of a comprehensive evaluation of radar and {L}i{DAR} altimeters with varying sensor specifications for river water level retrieval, seasonal change characterization, and water surface slope ({WSS}) using gauged long-term water level and global navigation satellite system data. {T}his study addresses this gap by combined evaluation of radar ({ENVISAT} to {S}entinel-3) and {L}i{DAR} ({ICES}at-1, {ICES}at-2) altimeters along the {G}anga {R}iver, from {P}rayagraj to {V}aranasi. {W}e found that all the radar altimetry missions showed better accuracy for water level retrievals ({R}-2 > = 0.8; {RMSE} 0.11 to 1.16 m) and water level change quantification ({RMSE} 0.59 m). {H}owever, {S}entinel-3 with synthetic aperture radar ({SAR}) acquisition mode outperformed ({RMSE} 0.11 to 0.14 m) all the radar missions having low resolution mode. {D}espite {L}i{DAR} missions' high vertical accuracy, they show relatively lower accuracy in water level time series generation due to nonrepeating characteristics. {I}n contrary, {ICES}at-2 demonstrates potential in capturing spatial and seasonal variability of {WSS}, enhancing the accuracy of surface water and ocean topography ({SWOT}) discharge products when combined with {SWOT} {R}iver database. {T}his study provides a comprehensive baseline for end-users interested in utilizing radar and {L}i{DAR} missions for various hydrological applications, including river discharge estimation. {M}oreover, the studied river reach shares the {SWOT} calibration orbit, allowing the utilization of generated satellite and in-situ databases for the effective evaluation of {SWOT} measurements.},
  keywords = {{R}ivers ; {L}aser radar ; {A}ltimetry ; {S}paceborne radar ; {R}adar ; {W}ater resources ; {E}xtraterrestrial measurements ; {G}anga river ; {ICES}at-2 ; {L}i{DAR} ; altimetry ; radar altimetry ; remote sensing ; surface water and ocean ; topography ({SWOT}) mission ; {INDE} ; {GANGE}},
  booktitle = {},
  journal = {{IEEE} {J}ournal of {S}elected {T}opics in {A}pplied {E}arth {O}bservations and {R}emote {S}ensing},
  volume = {17},
  numero = {},
  pages = {7825--7840},
  ISSN = {1939-1404},
  year = {2024},
  DOI = {10.1109/jstars.2024.3379874},
  URL = {https://www.documentation.ird.fr/hor/fdi:010091042},
}