@article{fdi:010067753,
  title = {{P}rojected decreases in future marine export production : the role of the carbon flux through the upper ocean ecosystem},
  author = {{L}aufkotter, {C}. and {V}ogt, {M}. and {G}ruber, {N}. and {A}umont, {O}livier and {B}opp, {L}. and {D}oney, {S}. {C}. and {D}unne, {J}. {P}. and {H}auck, {J}. and {J}ohn, {J}. {G}. and {L}ima, {I}. {D}. and {S}eferian, {R}. and {V}olker, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A}ccurate projections of marine particle export production ({EP}) are crucial for predicting the response of the marine carbon cycle to climate change, yet models show a wide range in both global {EP} and their responses to climate change. {T}his is, in part, due to {EP} being the net result of a series of processes, starting with net primary production ({NPP}) in the sunlit upper ocean, followed by the formation of particulate organic matter and the subsequent sinking and remineralisation of these particles, with each of these processes responding differently to changes in environmental conditions. {H}ere, we compare future projections in {EP} over the 21st century, generated by four marine ecosystem models under the high emission scenario {R}epresentative {C}oncentration {P}athways ({RCP}) 8.5 of the {I}ntergovernmental {P}anel on {C}limate {C}hange ({IPCC}), and determine the processes driving these changes. {T}he models simulate small to modest decreases in global {EP} between -1 and -12 %. {M}odels differ greatly with regard to the drivers causing these changes. {A}mong them, the formation of particles is the most uncertain process with models not agreeing on either magnitude or the direction of change. {T}he removal of the sinking particles by remineralisation is simulated to increase in the low and intermediate latitudes in three models, driven by either warming-induced increases in remineralisation or slower particle sinking, and show insignificant changes in the remaining model. {C}hanges in ecosystem structure, particularly the relative role of diatoms matters as well, as diatoms produce larger and denser particles that sink faster and are partly protected from remineralisation. {A}lso this controlling factor is afflicted with high uncertainties, particularly since the models differ already substantially with regard to both the initial (presentday) distribution of diatoms (between 11-94% in the {S}outhern {O}cean) and the diatom contribution to particle formation (0.6-3.8 times higher than their contribution to biomass). {A}s a consequence, changes in diatom concentration are a strong driver for {EP} changes in some models but of low significance in others. {O}bservational and experimental constraints on ecosystem structure and how the fixed carbon is routed through the ecosystem to produce export production are urgently needed in order to improve current generation ecosystem models and their ability to project future changes.},
  keywords = {},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {13},
  numero = {13},
  pages = {4023--4047},
  ISSN = {1726-4170},
  year = {2016},
  DOI = {10.5194/bg-13-4023-2016},
  URL = {https://www.documentation.ird.fr/hor/fdi:010067753},
}