@article{fdi:010088125,
  title = {{A}ir-sea fluxes of {CO}2 in the {I}ndian {O}cean between 1985 and 2018 : a synthesis based on observation-based surface co2, hindcast and atmospheric inversion models},
  author = {{S}arma, {V}vss and {S}ridevi, {B}. and {M}etzl, {N}. and {P}atra, {P}. {K}. and {L}achkar, {Z}. and {C}hakraborty, {K}. and {G}oyet, {C}. and {L}evy, {M}arina and {M}ehari, {M}. and {C}handra, {N}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {I}ndian {O}cean significantly influences the global carbon cycle but it is one of the undersampled regions with reference to surface ocean p{CO}(2). {A}s a part of the {R}egional {C}arbon {C}ycle {A}ssessment and {P}rocesses-2 ({RECCAP}2) project, several approaches, such as interpolated observational climatology, hindcast model, observation-based surface {CO}2 (empirical models), and atmospheric inversion models have been employed for estimating net sea-to-air {CO}2 fluxes between 1985 and 2018. {T}he seasonal, spatial and long-term variability in sea-to-air fluxes of {CO}2 were compared with observational climatology. {T}he mean value of {CO}2 in the {I}ndian {O}cean (north of 37.5 degrees {S}) for the period of 1985-2018 using all models is estimated to be -0.19 +/- 0.1 {P}g{C} yr(-1) and it is consistent with the observational climatology (-0.07 +/- 0.14 {P}g{C} yr(-1)). {T}he {I}ndian {O}cean north of 18 degrees {S} is found to be the mean annual source (0.04 +/- 0.05 {P}g{C} yr-1) whereas a net sink (-0.23 +/- 0.11 {P}g{C} yr(-1)) in the south of 18 degrees {S}. {A}ll models captured observed spatial patterns but underestimated the net source of {CO}2 in the {O}man/{S}omalia upwelling, the {E}quatorial {I}ndian {O}cean and the {B}ay of {B}engal whereas {CO}2 sink is overestimated in the {S}outh {I}ndian {O}cean. {O}verall, all models captured the seasonality in p{CO}(2) levels and {CO}2 fluxes but overestimated the amplitude of their variability. {A}ll models suggested the strengthening of the sink over the period between 1985 and 2018 by 0.02 {P}g{C} yr(-1) decade(-1). {A} significant increase in the collection of surface ocean p{CO}(2) and atmospheric {CO}2 measurements improves the model simulations in the {I}ndian {O}cean. {P}lain {L}anguage {S}ummary {T}he {I}ndian {O}cean is under-sampled with reference to p{CO}(2) levels and {CO}2 fluxes. {W}e evaluated the {CO}2 fluxes simulated by different models based on observational {CO}2 flux climatology. {T}he {CO}2 fluxes estimated by all models are close to climatological value; however under and/ or overestimation of fluxes are noticed in several regions. {D}ue to weaker monsoon mixing, accurate river discharge data and atmospheric deposition of pollutants in the model, they failed to reproduce actual {CO}2 fluxes. {I}nclusion of such processes in the model improves their performance in future.},
  keywords = {surface p{CO}(2) ; {CO}2 fluxes ; hindcast models ; atmospheric inversions ; {I}ndian {O}cean ; {OCEAN} {INDIEN}},
  booktitle = {},
  journal = {{G}lobal {B}iogeochemical {C}ycles},
  volume = {37},
  numero = {5},
  pages = {e2023{GB}007694 [24 p.]},
  ISSN = {0886-6236},
  year = {2023},
  DOI = {10.1029/2023gb007694},
  URL = {https://www.documentation.ird.fr/hor/fdi:010088125},
}