@article{PAR00013487,
  title = {{G}lobal-scale evaluation of roughness effects on {C}-band {AMSR}-{E} observations},
  author = {{W}ang, {S}. and {W}igneron, {J}. {P}. and {J}iang, {L}. {M}. and {P}arrens, {M}. and {Y}u, {X}. {Y}. and {A}l-{Y}aari, {A}. and {Y}e, {Q}. {Y}. and {F}ernandez-{M}oran, {R}. and {J}i, {W}. and {K}err, {Y}ann},
  editor = {},
  language = {{ENG}},
  abstract = {{Q}uantifying roughness effects on ground surface emissivity is an important step in obtaining high-quality soil moisture products from large-scale passive microwave sensors. {I}n this study, we used a semi-empirical method to evaluate roughness effects (parameterized here by the {H}r parameter) on a global scale from {AMSR}-{E} ({A}dvanced {M}icrowave {S}canning {R}adiometer for {EOS}) observations. {AMSR}-{E} brightness temperatures at 6.9 {GH}z obtained from {J}anuary 2009 to {S}eptember 2011, together with estimations of soil moisture from the {SMOS} ({S}oil {M}oisture and {O}cean {S}alinity) {L}3 products and of soil temperature from {ECMWF}'s ({E}uropean {C}entre for {M}edium-range {W}eather {F}orecasting) were used as inputs in a retrieval process. {I}n the first step, we retrieved a parameter (referred to as the a* parameter) accounting for the combined effects of roughness and vegetation. {T}hen, global {MODIS} {NDVI} data were used to decouple the effects of vegetation from those of surface roughness. {F}inally, global maps of the {H}r parameters were produced and discussed. {I}nitial results showed that some spatial patterns in the {H}r values could be associated with the main vegetation types (higher values of {H}r were retrieved generally in forested regions, intermediate values were obtained over crops and grasslands, and lower values were obtained over shrubs and desert) and topography. {F}or instance, over the {USA}, lower values of {H}r were retrieved in relatively flat regions while relatively higher values were retrieved in hilly regions.},
  keywords = {},
  booktitle = {},
  journal = {{R}emote {S}ensing},
  volume = {7},
  numero = {5},
  pages = {5734--5757},
  ISSN = {2072-4292},
  year = {2015},
  DOI = {10.3390/rs70505734},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00013487},
}