Richard A. Feely1, Brendan Carter1, Nina Bednarsek1,2, Simone R. Alin1 and Jan Newton3 1Pacific Marine Environmental Laboratory/NOAA 2Southern California Coastal Research Project 3University of Washington
Ocean Acidification Processes along the Pacific Coast
Photocredit:MeghanShea
Outline u Anthropogenic CO2 Increases u Effect of Increasing Revelle Factor
On behalf of the project scientists at PMEL and our many national and international partners
CaliforniaOATaskForceWebinarMay29,2018
Accomplishments:Repeathydrography(left)continuestodemonstratethegrowingglobaloceanCO2sinkwhilefixedtimeseriesstations(top)illuminatehowinterannualevents,suchas“theblob,”impactCO2flux(fromCarteretal.2017;Carteretal.inprep;Feelyetal.2018;Suttonetal.2017)
Pacific anthropogenic carbon from 1995 to 2015
Dep
th [m
]
winter/spring2014-15warm
anomaly
[µmol kg-1]
AnthropogenicCarbonDioxideConcentrationsandpCO2IncreaseintheNorthPacific
AnIntegratedFederal-StateWestCoastOceanAcidificationObservingNetwork
Alinetal.2015,inpress(L);Chavezetal.2017(R)
Tunedtolocal/regionalneedsandprovidingreal-timeinformationtostakeholdersandpartnersvia theIOOSPacificRegionOceanAcidificationDataPortal(ipacoa.org)
• Increasing CO2 levels in the ocean increases its acidity (lowers its pH). These processes are faster in California coastal waters due to the combined effects of acidification, upwelling, and local carbon and nutrient sources.
• Observations and modeling studies indicate that local anthropogenic carbon and nutrient sources provide significant contributions to local acidification but vary widely depending on location.
AragoniteSaturationDepth(m)(2016) AragoniteSaturationDepth(m)(2007)
NOAAWestCoastCruise8May–6June2016comparedwithMay-June2007
u AragonitesaturationdepthindicatesstrongupwellingnearthecoastfromnorthernCaliforniatoVancouverIsland.
RichardFeely–PMEL
AnthropogenicCO2vspotentialdensityintheCaliforniaCurrentSystem
2013
200720112004
AnthropogenicCO2iscalculatedfromPO2RepeatHydrographycruisesin2004and2013andtheninterpolatedontoCaliforniaCurrentSystempotentialdensitysurfaces.
AnthropogenicCarbonDistributionsin2016
Feelyetal.,inprep
May-June2016Canthµmolkg-1
• HighCanthsurfacevalues(55-66µmolkg-1)offshoreandtothesouth
• LowCanthsubsurfacevalues
(40-54µmolkg-1)inonshorewatersfromHecataHeadtoPointReyes
• LowCanthwaterseverywherebelow100m
Evolution of chemical conditions in the California Current EcosystemDecadal trend in anthropogenic carbon concentration andaragonite saturation changes from the preindustrial to present
AnthropogenicCO2(µmol/kg) Changeinaragonitesaturationstate
Evolution of chemical conditions in the California Current EcosystemDecadal trend in anthropogenic carbon rate of change in the water column
pH:lowerinWestCoastsurfacewaterssimilardecreasesfrompresent-dayΩarag:lowerinWestCoastsurfacewaterslargerdecreasesinGOMfrompresentRF=(∆pCO2/pCO2)/(∆DIC/DIC)changesmorerapidlyinthecoolerWestCoastwaters
Surfacewaterchangesovertime
Feelyetal(2018)
Past,PresentandFutureImpactsofOceanAcidification
IncoastalenvironmentsliketheSalishSea,theincreasinganthropogeniccarbonreducestheabilityofthesystemtobuffernaturalvariationsinCO2.ThisreducedbufferingcapacityleadstopreferentialamplificationofnaturallyextremelowpHandhighpCO2(s.w.) events above changes in average conditions,whichoutpacerates published for atmospheric and open-ocean CO2 change. -Pacella et al., PNAS2018
.u Our major challenge is to determine anthropogenic ocean acidification
changes and biological responses against a backdrop of large natural variability. Approach to Solve: Collaborative Monitoring and Modeling
u Co-located chemical/biological field observations provide unique opportunities to observe and understand long-term changes as impacted by ocean acidification and hypoxia. Approach to Solve: Collaborative Monitoring and Modeling
u Oyster larvae, Pteropods and Crab larvae exhibit physiological responses that appear to be impacted by ocean acidification now. Approach to Solve: Continued Collaborative Field and Laboratory Studies
Conclusions