@article{fdi:010070866,
  title = {{I}ntercomparison of the {A}rctic sea ice cover in global ocean-sea ice reanalyses from the {ORA}-{IP} project [+ {E}rratum]},
  author = {{C}hevallier, {M}. and {S}mith, {G}. {C}. and {D}upont, {F}. and {L}emieux, {J}. {F}. and {F}orget, {G}. and {F}ujii, {Y}. and {H}ernandez, {F}abrice and {M}sadek, {R}. and {P}eterson, {K}. {A}. and {S}torto, {A}. and {T}oyoda, {T}. and {V}aldivieso, {M}. and {V}ernieres, {G}. and {Z}uo, {H}. and {B}almaseda, {M}. and {C}hang, {Y}. {S}. and {F}erry, {N}. and {G}arric, {G}. and {H}aines, {K}. and {K}eeley, {S}. and {K}ovach, {R}. {M}. and {K}uragano, {T}. and {M}asina, {S}. and {T}ang, {Y}. {M}. and {T}sujino, {H}. and {W}ang, {X}. {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{O}cean-sea ice reanalyses are crucial for assessing the variability and recent trends in the {A}rctic sea ice cover. {T}his is especially true for sea ice volume, as long-term and large scale sea ice thickness observations are inexistent. {R}esults from the {O}cean {R}e{A}nalyses {I}ntercomparison {P}roject ({ORA}-{IP}) are presented, with a focus on {A}rctic sea ice fields reconstructed by state-of-the-art global ocean reanalyses. {D}ifferences between the various reanalyses are explored in terms of the effects of data assimilation, model physics and atmospheric forcing on properties of the sea ice cover, including concentration, thickness, velocity and snow. {A}mongst the 14 reanalyses studied here, 9 assimilate sea ice concentration, and none assimilate sea ice thickness data. {T}he comparison reveals an overall agreement in the reconstructed concentration fields, mainly because of the constraints in surface temperature imposed by direct assimilation of ocean observations, prescribed or assimilated atmospheric forcing and assimilation of sea ice concentration. {H}owever, some spread still exists amongst the reanalyses, due to a variety of factors. {I}n particular, a large spread in sea ice thickness is found within the ensemble of reanalyses, partially caused by the biases inherited from their sea ice model components. {B}iases are also affected by the assimilation of sea ice concentration and the treatment of sea ice thickness in the data assimilation process. {A}n important outcome of this study is that the spatial distribution of ice volume varies widely between products, with no reanalysis standing out as clearly superior as compared to altimetry estimates. {T}he ice thickness from systems without assimilation of sea ice concentration is not worse than that from systems constrained with sea ice observations. {A}n evaluation of the sea ice velocity fields reveals that ice drifts too fast in most systems. {A}s an ensemble, the {ORA}-{IP} reanalyses capture trends in {A}rctic sea ice area and extent relatively well. {H}owever, the ensemble can not be used to get a robust estimate of recent trends in the {A}rctic sea ice volume. {B}iases in the reanalyses certainly impact the simulated air-sea fluxes in the polar regions, and questions the suitability of current sea ice reanalyses to initialize seasonal forecasts.},
  keywords = {{I}ce-ocean reanalysis ; {M}odel intercomparison ; {A}rctic ; {S}ea ice ; {D}ata assimilation ; {I}ce thickness ; {OCEAN} {ARTIQUE}},
  booktitle = {{O}cean estimation from an ensemble of global ocean reanalyses},
  journal = {{C}limate {D}ynamics},
  volume = {49},
  numero = {3 ({N}o sp{\'e}cial)},
  pages = {1107--1136 +2},
  ISSN = {0930-7575},
  year = {2017},
  DOI = {10.1007/s00382-016-2985-y},
  URL = {https://www.documentation.ird.fr/hor/fdi:010070866},
}