Student: Paul Welle Collaborators: Ines Azevedo Mitchell Small Sarah Cooley Scott Doney
Coastal & Ocean Acidification Scott Doney & Jennie Rheuban€¦ · Rheuban et al. Frontiers of...
Transcript of Coastal & Ocean Acidification Scott Doney & Jennie Rheuban€¦ · Rheuban et al. Frontiers of...
4TH ANNUAL CAPE COASTAL CONFERENCE
Coastal & Ocean Acidification
Scott Doney & Jennie Rheuban
Ocean Acidification Basics
Feely et al. Oceanography 2009
National Climate Assessment
Walsh et al. 2014
Fossil Fuel Carbon Emissions
Rising Atmospheric
Carbon Dioxide
Changing
Seawater Chemistry
Impacts on
Shellfish &
Other Marine Life
Fate of Anthropogenic CO2 Emissions (2006-2015)
LeQuere et al. Earth Systems Science Data 2016; Global Carbon Project 2016
~10 billion tons
carbon per year +
Atmosphere
45%
Land
30%
Oceans
25%
Fossil Fuels 90%
Deforestation 10%
Rising
Atmospheric
CO2
IPCC AR5
WG1 Chap. 6
2000 1800 1500 500 0
IPCC AR5
WG1 Chap. 6
2− [CO3 ] [CO2]
100−150%
50%
2100
8.2
8.1
8.0
7.9
7.8 1800 1900 2000 2100
50
40
30
20
10
0
300
240
180
120
60
0
pH
μ
mo
l kg−1
Year
pH
CO2(aq)
CO3 2−
30% acidity
16% [CO3 ]
2000
2−
Wolf-Gladrow et al. 1999
Ocean Acidification
CO2 + H2O H+ + CO3 2-
HCO3 -
H+ + HCO3 -
CO2 + CO3
2- 2HCO3
-
Seawater pH Trend
Surface ocean water
Hawaii Ocean Time-Series (HOT)
Calcium Carbonate Solubility Saturation State
Ca + CO3 CaCO3 (solid) 2- 2+
Saturation State
= [Ca2+][CO32-] / Ksp
>1 saturated
<1 undersaturated
CaCO3 solubility
-depends on mineral form
-increases with pressure
Feely et al. Nature 2005; Bednaršek Nature Geosci. 2012
Saturation
State along
Northeast
Shelf
Wang et al. Limnology &
Oceanography 2013
Distance From Shore (km)
Low saturation
state on shelf
De
pth
(m
)
Gledhill et al.
Oceanography 2015
Marine Life Susceptible to
Ocean Acidification
-Winners & losers
-Reduced shell & skeleton
formation (calcification)
-Habitat loss
-Less available prey &
smaller fisheries
-Other effects on growth,
behavior, diseases, …
Biological
Impacts on
Molluscs
Kroecker et al. (2009; 2013)
positive effect
negative effect
Negative Impacts of CO2 on Mollusks
Talmage et al.
PNAS 2010
Present
Future
(estuaries)
Eastern Oyster
Larvae
US Northeast Fisheries (Landings Value)
Gledhill et al.
Oceanography 2015
Cooley & Doney
Environ. Res. Letters
2009
Sea Scallop Fishery
Hart and Chute 2004
Cooley et al.
PLoS One
2015
pH
Biomass
Revenue
Integrated
Assessment Model:
• biogeochemistry
• sea scallop
population
dynamics
• fishery socio-
economics
Other Local Sources of Coastal Acidification
Doney et al. PNAS 2007; Doney Science 2010; Kelly et al. Science 2011
Ocean Biological Pump, Acidification & Low Oxygen
O xygen (mm ol/L)
0 100 200 300 400
pH
(to
tal,
ca
lc)
7 .0
7.5
8.0
8.5
W aquoit Bay 2008 - 2010
1/1/08 1/1/09 1/1/10 1/1/11 1/1/12
Ox
yg
en
(m
mo
l/L
)
0
100
200
300
400M enauhant
Childs R iver
1/1/08 1/1/09 1/1/10 1/1/11 1/1/12
pH
(to
tal
sc
ale
)
7 .0
7.5
8.0
D. McCorkle
WHOI
Excess nutrients from local
pollution sources can lead to
low oxygen & acidic waters
Buzzards Bay Water Quality
Buzzards Bay
Coalition
Citizen Science Network
collecting summertime
data from 1992-present
Buzzards Bay Eutrophication
Chlorophyll
Total
Nitrogen
Rheuban et al.
Biogeosciences 2016
Chlorophyll
trend
Total Nitrogen
trend
Chlorophyll
Shellfish Suitability & Coastal Acidification
American Oyster
Bay Scallop
Blue Mussel
European Oyster
Quahog
Razor clam
Soft-shell clam
Surf clam
Human Nitrogen Source Trends
Williamson,
Rheuban et al.
Frontiers of Marine
Science, submitted
Animal Waste
Atmospheric
Deposition Wastewater
(treatment plants)
Fertilizer
Wastewater
(septic)
Ocean Acidification Depends
on Human Activities
Recent Carbon
Emission Trends
Stabilizing
Van Vuuren et al.
Climatic Change 2011
Le Quere et al.
Earth System Science Data
2016
Ocean & Coastal Acidification Fossil Fuel CO2 Emissions
Rising Atmospheric CO2
Changing
Seawater Chemistry
Impacts on Shellfish
& Other Marine Life
-Rising atmospheric CO2 levels are
causing increased ocean acidity
-Acidification can be exacerbated
in coastal waters by local nutrient
pollution
-Shellfish may be vulnerable to
ocean & coastal acidification
-Improved chemical & biological
monitoring are needed for coastal
waters
-More targeted work needed on
sensitivity of key commercial &
recreational shellfish fisheries
Extra Slides
Valued Human Uses for Buzzards Bay
Uses with economic value in terms of avoided costs
Uses with diminished economic values from eutrophication, which
may be exacerbated by warming, increased intense precipitation
Biological Impacts: Winners & Losers
Kroecker
et al.
Global
Change
Biology
(2013)
positive effect
negative effect