Factors affecting interdecadal variability of air–sea CO2 fluxes in the tropical Pacific, revealed by an ocean physical–biogeochemical model

Abstract

The tropical Pacific is the largest source region of CO2 release to the atmosphere through the sea surface, with air–sea CO2 fluxes varying on seasonal to interdecadal timescales, which is attributed to several factors. At present, there is no consensus on the relative contributions of wind speed and ΔpCO2 (the partial pressure of CO2 [pCO2] difference between sea surface and the atmosphere) to the interdecadal variability of CO2 fluxes, especially concerning their linkage with the Interdecadal Pacific Oscillation (IPO). By using a coupled ocean physical–biogeochemical model forced by the NCEP/NCAR winds during 1958–2016, we show that the CO2 fluxes exhibit interdecadal regime shifts in 1975–1976 and 1997–1998, which is coincident with the regime transitions of the IPO. Furthermore, the interdecadal variability of wind speed is demonstrated to play a significant role in determining the magnitude and location of interdecadal variability of CO2 fluxes, while the contribution of ΔpCO2 is relatively small. Additionally, the location of maximum variability of CO2 fluxes gradually migrates westward during 1958–2016, which is related to the interdecadal change in the relationship between wind speed and CO2 fluxes. Modelling results suggest that the regime shifts of CO2 fluxes in the future decades may significantly influence the projection of long-term trend in CO2 fluxes in the tropical Pacific Ocean.

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References

  1. An S-I (2018) Impact of Pacific decadal oscillation on frequency asymmetry of El Niño and La Niña Events. Adv Atmos Sci 35:493–494. https://doi.org/10.1007/s00376-018-8024-7

    Article  Google Scholar 

  2. Ashok K, Yamagata T (2009) Climate change: the El Niño with a difference. Nature 461:481–484. https://doi.org/10.1038/461481a

    Article  Google Scholar 

  3. Bakker DCE, Pfeil B, Landa CS et al (2016) A multi-decade record of high-quality fCO2 data in version 3 of the surface ocean CO2 Atlas (SOCAT). Earth Syst Sci Data 8:383–413. https://doi.org/10.5194/essd-8-383-2016

    Article  Google Scholar 

  4. Bordbar MH, Martin T, Latif M, Park W (2017) Role of internal variability in recent decadal to multidecadal tropical Pacific climate changes. Geophys Res Lett 44:4246–4255. https://doi.org/10.1002/2016GL072355

    Article  Google Scholar 

  5. Boyce DG, Lewis MR, Worm B (2010) Global phytoplankton decline over the past century. Nature 466:591–596. https://doi.org/10.1038/nature09268

    Article  Google Scholar 

  6. Chen X, Tung K-K (2018) Global-mean surface temperature variability: space–time perspective from rotated EOFs. Clim Dyn 51:1719–1732. https://doi.org/10.1007/s00382-017-3979-0

    Article  Google Scholar 

  7. Chen D, Rothstein LM, Busalacchi AJ (1994) A hybrid vertical mixing scheme and its application to tropical ocean models. J Phys Oceanogr 24:2156–2179. https://doi.org/10.1175/1520-0485(1994)024%3c2156:AHVMSA%3e2.0.CO;2

    Article  Google Scholar 

  8. Choi J, Il An S, Yeh SW (2012) Decadal amplitude modulation of two types of ENSO and its relationship with the mean state. Clim Dyn 38:2631–2644. https://doi.org/10.1007/s00382-011-1186-y

    Article  Google Scholar 

  9. Collins M, An S-I, Cai W et al (2010) The impact of global warming on the tropical Pacific Ocean and El Niño. Nat Geosci 3:391–397. https://doi.org/10.1038/ngeo868

    Article  Google Scholar 

  10. DiNezio PN, Barbero L, Long MC et al (2015) Are anthropogenic changes in the tropical ocean carbon cycle being masked by Pacific decadal variability? US CLIVAR 13:12–16

    Google Scholar 

  11. Doney SC, Tilbrook B, Roy S et al (2009) Surface-ocean CO2 variability and vulnerability. Deep Res Part II Top Stud Oceanogr 56:504–511. https://doi.org/10.1016/j.dsr2.2008.12.016

    Article  Google Scholar 

  12. Dunne JP, Laufkötter C, Frölicher TL (2015) Ocean biogeochemistry in the fifth coupled model intercomparison project (CMIP5). CLIVAR Newsl 13:1–29

    Google Scholar 

  13. England MH, McGregor S, Spence P et al (2014) Recent intensification of wind-driven circulation in the Pacific and the ongoing warming hiatus. Nat Clim Chang 4:222–227. https://doi.org/10.1038/NCLIMATE2106

    Article  Google Scholar 

  14. Fay AR, McKinley GA (2013) Global trends in surface ocean pCO2 from in situ data. Global Biogeochem Cycles 27:541–557. https://doi.org/10.1002/gbc.20051

    Article  Google Scholar 

  15. Feely RA, Wanninkhof R, Takahashi T, Tans P (1999) Influence of El Niño on the equatorial Pacific contribution to atmospheric CO2 accumulation. Nature 398:597. https://doi.org/10.1038/19273

    Article  Google Scholar 

  16. Feely RA, Takahashi T, Wanninkhof R et al (2006) Decadal variability of the air–sea CO2 fluxes in the equatorial Pacific Ocean. J Geophys Res 111:C08S90. https://doi.org/10.1029/2005jc003129

    Article  Google Scholar 

  17. Gent PR, Cane MA (1989) A reduced gravity, primitive equation model of the upper equatorial ocean. J Comput Phys 81:444–480. https://doi.org/10.1016/0021-9991(89)90216-7

    Article  Google Scholar 

  18. Gu D, Philander SGH (1997) Interdecade climate fluctuations that depend on exchanges between the tropic and extratropics. Science (80-) 275:805–807

    Article  Google Scholar 

  19. Han W, Meehl GA, Hu A et al (2014) Intensification of decadal and multi-decadal sea level variability in the western tropical Pacific during recent decades. Clim Dyn 43:1357–1379. https://doi.org/10.1007/s00382-013-1951-1

    Article  Google Scholar 

  20. Hu S, Fedorov AV (2017) The extreme El Niño of 2015–2016 and the end of global warming hiatus. Geophys Res Lett 44:3816–3824. https://doi.org/10.1002/2017GL072908

    Article  Google Scholar 

  21. Huang B, Thorne PW, Banzon VF et al (2017) Extended reconstructed sea surface temperature version 5 (ERSSTv5): upgrades, validations, and intercomparisons. J Clim 5:8179–8205. https://doi.org/10.1175/jcli-d-16-0836.1

    Article  Google Scholar 

  22. Ishii M, Inoue HY, Midorikawa T et al (2009) Spatial variability and decadal trend of the oceanic CO2 in the western equatorial Pacific warm/fresh water. Deep Res Part II Top Stud Oceanogr 56:591–606. https://doi.org/10.1016/j.dsr2.2009.01.002

    Article  Google Scholar 

  23. Ishii M, Feely RA, Rodgers KB et al (2014) Air-sea CO2 flux in the Pacific Ocean for the period 1990–2009. Biogeosciences 11:709–734. https://doi.org/10.5194/bg-11-709-2014

    Article  Google Scholar 

  24. Kalnay E, Kanamitsu M, Kistler R et al (1996) The NCEP/NCAR 40-year reanalysis project. Bull Am Meteorol Soc 77:437–471. https://doi.org/10.1175/1520-0477(1996)077%3c0437:TNYRP%3e2.0.CO;2

    Article  Google Scholar 

  25. Kang X, Zhang R-H, Wang G (2017) Effects of different freshwater flux representations in an ocean general circulation model of the tropical Pacific. Sci Bull 62:345–351. https://doi.org/10.1016/j.scib.2017.02.002

    Article  Google Scholar 

  26. Kosaka Y, Xie S-P (2013) Recent global-warming hiatus tied to equatorial Pacific surface cooling. Nature 501:403–407. https://doi.org/10.1038/nature12534

    Article  Google Scholar 

  27. Kug J-S, Jin F-F, An S-I (2009) Two types of El Niño events: cold tongue El Niño and warm Pool El Niño. J Clim 22:1499–1515. https://doi.org/10.1175/2008JCLI2624.1

    Article  Google Scholar 

  28. Landschützer P, Gruber N, Bakker DCE, Schuster U (2014) Recent variability of the global ocean carbon sink. Global Biogeochem Cycles 28:927–949. https://doi.org/10.1002/2014GB004853

    Article  Google Scholar 

  29. Landschützer P, Gruber N, Bakker DCE (2016) Decadal variations and trends of the global ocean carbon sink. Global Biogeochem Cycles 30:1396–1417. https://doi.org/10.1002/2015GB005359

    Article  Google Scholar 

  30. Le Quéré C, Orr JC, Monfray P et al (2000) Interannual variability of the oceanic sink of CO2 from 1979 through 1997. Global Biogeochem Cycles 14:1247–1265. https://doi.org/10.1029/1999GB900049

    Article  Google Scholar 

  31. Lin R, Zheng F, Dong X (2018) ENSO frequency asymmetry and the Pacific decadal oscillation in observations and 19 CMIP5 models. Adv Atmos Sci 35:495–506. https://doi.org/10.1007/s00376-017-7133-z

    Article  Google Scholar 

  32. Liu Z (2012) Dynamics of interdecadal climate variability: a historical perspective*. J Clim 25:1963–1995. https://doi.org/10.1175/2011JCLI3980.1

    Article  Google Scholar 

  33. Mantua NJ, Hare SR, Zhang Y et al (1997) A Pacific interdecadal climate oscillation with impacts on salmon production. Bull Am Meteorol Soc 78:1069–1079. https://doi.org/10.1175/1520-0477(1997)078%3c1069:APICOW%3e2.0.CO;2

    Article  Google Scholar 

  34. McKinley GA, Fay AR, Lovenduski NS, Pilcher DJ (2017) Natural variability and anthropogenic trends in the ocean carbon sink. Ann Rev Mar Sci 9:125–150. https://doi.org/10.1146/annurev-marine-010816-060529

    Article  Google Scholar 

  35. McPhaden MJ, Zhang D (2002) Slowdown of the meridional overturning circulation in the upper Pacific Ocean. Nature 415:603–608. https://doi.org/10.1038/415603a

    Article  Google Scholar 

  36. Meehl GA, Hu A, Teng H (2016) Initialized decadal prediction for transition to positive phase of the Interdecadal Pacific Oscillation. Nat Commun 7:1–7. https://doi.org/10.1038/ncomms11718

    Article  Google Scholar 

  37. Murtugudde R, Seager R, Busalacchi A (1996) Simulation of the tropical oceans with an ocean GCM coupled to an atmospheric mixed-layer model. J Clim 9:1795–1815. https://doi.org/10.1175/1520-0442(1996)009%3c1795:SOTTOW%3e2.0.CO;2

    Article  Google Scholar 

  38. Newman M, Compo GP, Alexander MA (2003) ENSO-forced variability of the Pacific decadal oscillation. J Clim 16:3853–3857. https://doi.org/10.1175/1520-0442(2003)016%3c3853:EVOTPD%3e2.0.CO;2

    Article  Google Scholar 

  39. Patra PK, Maksyutov S, Ishizawa M et al (2005) Interannual and decadal changes in the sea-air CO2 flux from atmospheric CO2 inverse modeling. Global Biogeochem Cycles. https://doi.org/10.1029/2004gb002257

    Article  Google Scholar 

  40. Power S, Casey T, Folland C et al (1999) Inter-decadal modulation of the impact of ENSO on Australia. Clim Dyn 15:319–324. https://doi.org/10.1007/s003820050284

    Article  Google Scholar 

  41. Rayner PJ, Law RM, Dargaville R (1999) The relationship between tropical CO2 fluxes and the El Niño-Southern Oscillation. Geophys Res Lett 26:493–496. https://doi.org/10.1029/1999GL900008

    Article  Google Scholar 

  42. Roobaert A, Laruelle GG, Landschützer P, Regnier P (2018) Uncertainty in the global oceanic CO2 uptake induced by wind forcing: quantification and spatial analysis. Biogeosciences 15:1701–1720. https://doi.org/10.5194/bg-15-1701-2018

    Article  Google Scholar 

  43. Sarmiento JL, Gruber N (2006) Ocean biogeochemical dynamics. Pricenton University Press, Princeton

    Google Scholar 

  44. Seager R, Blumenthal MB, Kushnir Y (1995) An advective atmospheric mixed layer model for ocean modeling purposes: global simulation of surface heat fluxes. J Clim 8:1951–1964. https://doi.org/10.1175/1520-0442(1995)008%3c1951:AAAMLM%3e2.0.CO;2

    Article  Google Scholar 

  45. Sharma P, Marinov I, Cabre A et al (2019) Increasing biomass in the warm oceans: unexpected new insights from SeaWiFS. Geophys Res Lett. https://doi.org/10.1029/2018gl079684

    Article  Google Scholar 

  46. Sutton AJ, Wanninkhof R, Sabine CL et al (2017) Variability and trends in surface seawater pCO2 and CO2 flux in the Pacific Ocean. Geophys Res Lett 44:5627–5636. https://doi.org/10.1002/2017GL073814

    Article  Google Scholar 

  47. Takahashi T, Olafsson J, Goddard JG et al (1993) Seasonal variation of CO 2 and nutrients in the high-latitude surface oceans: a comparative study. Global Biogeochem Cycles 7:843–878. https://doi.org/10.1029/93GB02263

    Article  Google Scholar 

  48. Takahashi T, Sutherland SC, Wanninkhof R et al (2009) Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans. Deep Res Part II Top Stud Oceanogr 56:554–577. https://doi.org/10.1016/j.dsr2.2008.12.009

    Article  Google Scholar 

  49. Trenberth KE, Hurrell JW (1994) Decadal atmosphere-ocean variations in the Pacific. Clim Dyn 9:303–319. https://doi.org/10.1007/BF00204745

    Article  Google Scholar 

  50. Tung K-K, Chen X, Zhou J, Li K-F (2019) Interdecadal variability in pan-Pacific and global SST, revisited. Clim Dyn 52:2145–2157. https://doi.org/10.1007/s00382-018-4240-1

    Article  Google Scholar 

  51. Valsala V, Roxy M, Ashok K, Murtugudde R (2014) Spatiotemporal characteritics of seasonal to multidecadal variability of pCO2 and air–sea CO2 fluxes in the equatorial Pacific Ocean. J Geophys Res Ocean 119:8987–9012. https://doi.org/10.1002/2014JC010212.Received

    Article  Google Scholar 

  52. Wang X, Christian JR, Murtugudde R, Busalacchi AJ (2006) Spatial and temporal variability of the surface water pCO2 and air–sea CO2 flux in the equatorial Pacific during 1980–2003: a basin-scale carbon cycle model. J Geophys Res Ocean 111:1–18. https://doi.org/10.1029/2005JC002972

    Article  Google Scholar 

  53. Wang X, Le Borgne R, Murtugudde R et al (2008) Spatial and temporal variations in dissolved and particulate organic nitrogen in the equatorial Pacific: biological and physical influences. Biogeosciences 5:1705–1721. https://doi.org/10.5194/bg-5-1705-2008

    Article  Google Scholar 

  54. Wang X, Murtugudde R, Hackert E et al (2015) Seasonal to decadal variations of sea surface pCO2 and sea-air CO2 flux in the equatorial oceans over 1984–2013: a basin-scale comparison of the Pacific and Atlantic Oceans. Global Biogeochem Cycles 29:597–609. https://doi.org/10.1002/2014GB005031

    Article  Google Scholar 

  55. Wanninkhof R (1992) Relationship between wind speed and gas exchange. J Geophys Res 97:7373–7382. https://doi.org/10.1029/92JC00188

    Article  Google Scholar 

  56. Wanninkhof R, Triñanes J (2017) The impact of changing wind speeds on gas transfer and its effect on global air–sea CO2 fluxes. Global Biogeochem Cycles 31:961–974. https://doi.org/10.1002/2016GB005592

    Article  Google Scholar 

  57. Wanninkhof R, Asher WE, Ho DT et al (2009) Advances in quantifying air–sea gas exchange and environmental forcing. Ann Rev Mar Sci 1:213–244. https://doi.org/10.1146/annurev.marine.010908.163742

    Article  Google Scholar 

  58. Wanninkhof R, Park GH, Takahashi T et al (2013) Global ocean carbon uptake: magnitude, variability and trends. Biogeosciences 10:1983–2000. https://doi.org/10.5194/bg-10-1983-2013

    Article  Google Scholar 

  59. Wetzel P, Winguth A, Maier-Reimer E (2005) Sea-to-air CO2 flux from 1948 to 2003: a model study. Global Biogeochem Cycles 19:1–19. https://doi.org/10.1029/2004GB002339

    Article  Google Scholar 

  60. Xiu P, Chai F (2014) Variability of oceanic carbon cycle in the North Pacific from seasonal to decadal scales. J Geophys Res Ocean 119:5270–5288. https://doi.org/10.1002/2013JC009505

    Article  Google Scholar 

  61. Yu JY, Kim ST (2010) Identification of Central-Pacific and Eastern-Pacific types of ENSO in CMIP3 models. Geophys Res Lett 37:1–7. https://doi.org/10.1029/2010GL044082

    Article  Google Scholar 

  62. Zhai P, Rodgers KB, Griffies SM et al (2017) Mechanistic drivers of reemergence of anthropogenic carbon in the equatorial pacific. Geophys Res Lett 44:9433–9439. https://doi.org/10.1002/2017GL073758

    Article  Google Scholar 

  63. Zhang R-H (2015) An ocean-biology-induced negative feedback on ENSO as derived from a hybrid coupled model of the tropical Pacific. J Geophys Res Ocean 120:8052–8076. https://doi.org/10.1002/2015JC011305

    Article  Google Scholar 

  64. Zhang R-H, Gao C (2016) The IOCAS intermediate coupled model (IOCAS ICM) and its real-time predictions of the 2015–2016 El Niño event. Sci Bull 61:1–10. https://doi.org/10.1007/s11434-016-1064-4

    Article  Google Scholar 

  65. Zhang R-H, Levitus S (1997) Structure and cycle of decadal variability of upper-ocean temperature in the North Pacific. J Clim 10:710–727. https://doi.org/10.1175/1520-0442(1997)010%3c0710:SACODV%3e2.0.CO;2

    Article  Google Scholar 

  66. Zhang R-H, Rothstein LM, Busalacchi AJ (1998) Origin of upper-ocean warming and El Niño change on decadal scales in the tropical Pacific Ocean. Nature 391:879–883. https://doi.org/10.1038/36081

    Article  Google Scholar 

  67. Zhang R-H, Rothstein LM, Busalacchi AJ (1999) Interannual and decadal variability of the subsurface thermal structure in the Pacific Ocean: 1961–90. Clim Dyn 15:703–717. https://doi.org/10.1007/s003820050311

    Article  Google Scholar 

  68. Zhang R-H, Tian F, Wang X (2018a) Ocean chlorophyll-induced heating feedbacks on ENSO in a coupled ocean physics-biology model forced by prescribed wind anomalies. J Clim 31:1811–1832. https://doi.org/10.1175/JCLI-D-17-0505.1

    Article  Google Scholar 

  69. Zhang R-H, Tian F, Wang X (2018b) A new hybrid coupled model of atmosphere, ocean physics, and ocean biogeochemistry to represent biogeophysical feedback effects in the tropical Pacific. J Adv Model Earth Syst 10:1901–1923. https://doi.org/10.1029/2017MS001250

    Article  Google Scholar 

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Acknowledgements

The authors wish to thank the anonymous reviewers and editor for their insightful comments that greatly helped to improve the original manuscript. We would like to thank Zeng-Zhen Hu, Jieshun Zhu, Zhaohua Wu for their comments. This research was supported by the National Natural Science Foundation of China (NFSC; Grant nos. 41475101, 41690122(41690120), 41490644(41490640), 41421005), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant no. XDA19060102), the NSFC-Shandong Joint Fund for Marine Science Research Centers (U1406402), and Taishan Scholarship. The data and computer codes used in the paper are available from the authors (e-mail: rzhang@qdio.ac.cn).

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Tian, F., Zhang, R. & Wang, X. Factors affecting interdecadal variability of air–sea CO2 fluxes in the tropical Pacific, revealed by an ocean physical–biogeochemical model. Clim Dyn 53, 3985–4004 (2019). https://doi.org/10.1007/s00382-019-04766-5

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Keywords

  • Tropical Pacific
  • Interdecadal variability of air–sea CO2 fluxes
  • Regime shift
  • Wind speed
  • Ocean physical–biogeochemical model