@article{fdi:010080546,
  title = {{E}stimation of multiple inflows and effective channel by assimilation of multi-satellite hydraulic signatures : the ungauged anabranching {N}egro river},
  author = {{P}ujol, {L}. and {G}arambois, {P}. {A}. and {F}inaud-{G}uyot, {P}. and {M}onnier, {J}. and {L}arnier, {K}. and {M}ose, {R}. and {B}iancamaria, {S}. and {Y}esou, {H}. and {M}oreira, {D}. and {P}aris, {A}. and {C}almant, {S}t{\'e}phane},
  editor = {},
  language = {{ENG}},
  abstract = {{W}ith the upcoming {SWOT} satellite mission, which should provide spatially dense river surface elevation, width and slope observations globally, comes the opportunity to assimilate such data into hydrodynamic models, from the reach scale to the hydrographic network scale. {B}ased on the {H}i{VDI} ({H}ierarchical {V}ariational {D}ischarge {I}nversion) modeling strategy ({L}arnier et al. (2020)), this study tackles the forward and inverse modeling capabilities of distributed channel parameters and multiple inflows (in the 1{D} {S}aint-{V}enant model) from multisatellite observations of river surface. {I}t is shown on synthetic cases that the estimation of both inflows and distributed channel parameters (bathymetry-friction) is achievable with a minimum spatial observability between inflows as long as their hydraulic signature is sampled. {N}ext, a real case is studied: 871 km of the {N}egro river ({A}mazon basin) including complex multichannel reaches, 21 tributaries and backwater controls from major confluences. {A}n effective modeling approach is proposed using (i) {WS} elevations from {ENVISAT} data and dense in situ {GPS} flow lines ({M}oreira (2016)), (ii) average river top widths from optical imagery ({P}ekel et al. (2016)), (iii) upstream and lateral flows from the {MGB} large-scale hydrological model ({P}aiva et al. (2013a)). {T}he calibrated effective hydraulic model closely fits satellite altimetry observations and presents real-like spatial variabilities; flood wave propagation and water surface observation frequential features are analyzed with identifiability maps following ({B}risset et al. (2018)). {S}ynthetic {SWOT} observations are generated from the simulated flowlines and allow to infer model parameters (436 effective bathymetry points, 17 friction patches and 22 upstream and lateral hydrographs) given hydraulically coherent prior parameter values. {I}nferences of channel parameters carried out on this fine hydraulic model applied at a large scale give satisfying results using noisy {SWOT}-like data at reach scale. {I}nferences of spatially distributed temporal parameters (lateral inflows) give satisfying results as well, with even relatively small scale hydrograph variations being inferred accurately on this long reach. {T}his study brings insights in: (i) the hydraulic visibility of the signatures of multiple inflow hydrographs at a large scale with {SWOT}; (ii) the simultaneous identifiability of spatially distributed channel parameters and inflows by assimilation of satellite altimetry data; (iii) the need for prior information; (iv) the need to further tailor and scale network hydrodynamic models and assimilation methods to improve the fusion of multisource information and potential information feedback to hydrological modules in integrated chains.},
  keywords = {1{D} {S}aint-{V}enant model ; {H}ydrology couplings ; {V}ariational assimilation ; {S}atellite altimetry ; {SWOT} ; {H}ydraulic visibility ; {U}ngauged river ; {COLOMBIE} ; {VENEZUELA} ; {BRESIL} ; {AMAZONE} {BASSIN} ; {RIO} {NEGRO}},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {591},
  numero = {},
  pages = {125331 [24 ]},
  ISSN = {0022-1694},
  year = {2020},
  DOI = {10.1016/j.jhydrol.2020.125331},
  URL = {https://www.documentation.ird.fr/hor/fdi:010080546},
}