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CityU Hong Kong Nov 09 11
Marine Ecosystems in a ChangingMarine Ecosystems in a Changing ClimateClimate
Ken Denman
Fisheries and Oceans Canada
EC Canadian Centre for Climate Modelling and Analysisc/o University of Victoria, BC, Canada
&Institute of Ocean Sciences, Sidney, BC
Email: [email protected]
U. Victoria
CityU Hong Kong Nov 09 2
'End to End' View of Marine Ecosystems'End to End' View of Marine Ecosystems
Plankton Nekton
SalpsSalps
JuvenileFinfish
JuvenileFinfish
SmallPelagics
SmallPelagics
?
WhalesWhales
AdultFinfishAdult
FinfishHumansHumans
SealsSeals
Sea lionsSea lions
Mass Flow
End Endto
CityU Hong Kong Nov 09 33
Ocean Ecosystems Ocean Ecosystems Climate Climate
1.Direct links between ocean ecosystems and climate,e.g.
– thermal regulation of physiological rates
– temperature affects biological sources and sinks for oxygen
2.Indirect links via 'Biogeochemistry', e.g.
– ocean biota regulate sequestration of atmospheric CO2 by the ocean by affecting surface pCO2, pH, export of C to ocean interior via 'biotic pumps‘, etc.
– oceanic biota regulate dissolved O2 concentrations, and hence production of the gases, N2 and especially N2O
3.Physical transport, e.g.– currents, mixing, gravitational sinking (& buoyant
rising)
CityU Hong Kong Nov 09 44
Future COFuture CO22 Emissions ScenariosEmissions Scenarios
[from Raupach et al., [from Raupach et al., US. Proc. Natl Acad SciUS. Proc. Natl Acad Sci
Vol. 104, 12 June 2007] Vol. 104, 12 June 2007] ##
20062005
20062005
# Updated from the Global Carbon Project website, Oct. 2008; & BP Statistical Review of World Energy, June 2009
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
1990 1995 2000 2005 2010
Fo
ssil
Fu
el E
mis
sio
n (
GtC
/y)
CDIACIEAall
A1B(Av)A1FI(Av)A1T(Av)A2(Av)
B1(Av)B2(Av)
Observed rate of increase (3.5 % /year) for 2000-07 is ~4 times that in 1990s
CityU Hong Kong Nov 09 5
[http://en.wikipedia.org/wiki/Human_development_index]
The Human Development IndexThe Human Development IndexCombines 4 measures & ranges from 0 to 1Combines 4 measures & ranges from 0 to 1• Life expectancy at birth• Literacy
UN Development Programme: [http://hdr.undp.org/]
• Education• GDP per capita
0.950 and over 0.900–0.949 0.850–0.8990.800–0.8490.750–0.7990.700–0.7490.650–0.6990.600–0.649 0.550–0.599 0.500–0.549 0.450–0.499 0.400–0.449 0.350–0.399 under 0.350 not available
CityU Hong Kong Nov 09 6
Human Development Index vs Human Development Index vs Per Capita Fossil Fuel Per Capita Fossil Fuel
EmissionsEmissions
Qatar 79.3
Trinidad and Tobago
Equatorial GuineaIndia
Canada
USA
IcelandNorwaySweden
Kuwait
China
0.0
0.2
0.4
0.6
0.8
1.0
0.1 1 10 100
Hong KongHong Kong
Hong KongHong Kong
CityU Hong Kong Nov 09 7
Natural Variability in N. Pacific Sea Surface Temperature (SST)
B. Projected model average decadal winter mean SST (2040-2049),relative to 1980-1999 patternfrom the Hadley Centre data
7
Climate Variability Is LargeClimate Variability Is Large
Jim Overland and Muyin Jim Overland and Muyin WangWang2007, EOS/AGU 88(16)2007, EOS/AGU 88(16)
A.OBSERVEDOBSERVED SST anomaly (Nov – SST anomaly (Nov – Mar) Mar) for 1901-1999 for 1901-1999
(from UK Hadley Centre SST (from UK Hadley Centre SST analysis)analysis)
A
CityU Hong Kong Nov 09 88
Warming Is Not Smooth: Natural Variability Can Warming Is Not Smooth: Natural Variability Can Reverse Warming Trend for a Decade or MoreReverse Warming Trend for a Decade or More
-3
-2
-1
0
1
2
3
2000 2020 2040 2060 2080 2100
Year
Sea
Su
rfac
e T
emp
erat
ure
An
om
aly
(oC
)
SRES Projected
Projected 'Observed'
SRES Scenario 'A1B' mean SSTfrom 10 IPCC-AR4 coupled models
Blue curve + observed 'variability' for
for the 20th century
Blue curve + observed Nov-Mar SST 'variability' for the 20th century from the Hadley Centre
N
ort
h P
acif
ic 2
0-60
ºN 'E
OF
1'
From Overland and Wang, 2007, EOS/AGU 88(16)
CityU Hong Kong Nov 09 99
T (C) highest in northern Polar regions during northern winter
(T, annual)
Fig. 11.21
Warming is NOT Spatially UniformWarming is NOT Spatially Uniform
Arctic 60o-90oN 2080-2090 minus 1980-1999 for 21 models
A1BA1B scenario
50% All
AR4 WG1 Fig. 11.19
Month
1010
12
14
88
66
4
2
0
Global mean warming Global mean warming for for A1B A1B scenarioscenario
is is 2.7°C2.7°C
55
77
44
CityU Hong Kong Nov 09 1010
'Best' 6 Models Predict 'Ice Free' Arctic 'Best' 6 Models Predict 'Ice Free' Arctic By September 2037By September 2037
•Retained 6 of 23 IPCC AR4 models based on simulation of seasonal cycle and Sept sea ice extent ±20% HadlISST for 1980-1999
•Year of 25th percentile is 20282028 and 75th percentile is 20482048 [Wang and Overland, 2009. Geophys. Res. Lett. 36, [Wang and Overland, 2009. Geophys. Res. Lett. 36,
L07502]L07502]
14 ensemble runs for eachof A1B and A2 scenarios
Sept 08
Medianice extent
Expect huge changes in Arctic ecosystemsExpect huge changes in Arctic ecosystems
CityU Hong Kong Nov 09 11
Most Recent Projection of Global Warming:Most Recent Projection of Global Warming:
The 'Roulette Wheel'
400 simulations with the MIT Integrated Global Systems Model:• improved economic analysis & modelling• includes effects of 20th century volcanic activity that was masking warming
Sokolov et al., accepted and on line, J. Climate.
Median Surface Warming 5.2°C (90%: 3.5 – 7.4°C)
(more than 80% probability warming greater than 4°C)
CityU Hong Kong Nov 09 1212
Projected: Projected: Warming, Freshening, Stratifying, Warming, Freshening, Stratifying, Longer Phyto. Growing Season, Less Ice CoverLonger Phyto. Growing Season, Less Ice Cover (Warming – Control) for 2040 to 2060 period
for 6 Climate Models
Sarmiento et al., 2004, Global Biochem. Cycles, 18(3)
g) Length ofGrowing Season
e) Strengthof Stratification
CityU Hong Kong Nov 09 13
Increasing Stratification Leads to Increasing Stratification Leads to Decreasing Net Primary Production (NPP) Decreasing Net Primary Production (NPP)
for SST>15for SST>15ºCºC
Global NPP
NPP, SST > 15oC
Incre
asin
Incre
asin
gg
Behrenfeld et al., 2006. Nature, 444, 752-755
SeaWiFS multi-band SeaWiFS multi-band ocean colour ocean colour satellitesatellite
CityU Hong Kong Nov 09 1414
AddingAdding CO CO22 Increases Ocean Acidity Increases Ocean Acidity K1 K2
CO2 + H2O HCO3- + H+ CO3
2- + 2H+
CO2 + H2O+ CO3
2- 2HCO3-
"Bjerrum plot"
CO2*
CityU Hong Kong Nov 09 1515
Open Ocean pH Is DecreasingOpen Ocean pH Is Decreasing
Figure 5.9
29N, 15W
23N, 158W
32N, 64W
1985 2005
Left
•Surface pCO2 increases with time
Right•Surface pH decreases
pH = -log [H+]
IPCC AR4 WG1 Fig. 5.9
HOTSHOTS
CityU Hong Kong Nov 09 1616
CCCma Ocean Model Surface pH CCCma Ocean Model Surface pH DecreaseDecrease
No Emissions
Observed + A2 Emissions
0.0.11
0.14 – 0.14 – 0.350.35
IPCIPCCCAR4AR4
Due primarily to adding Due primarily to adding COCO2 2 , not to the changing , not to the changing climateclimate
CityU Hong Kong Nov 09 17
The Acidification of the World OceanThe Acidification of the World Ocean
1950
p H
2000
2050
2100
'A2' Scenario from the Canadian Centre for Climate Modelling and Analysis (CCCMA) Earth System Model CanESM1: Zahariev, Christian & Denman, 2008; Arora et al., in press, J. Climate; Christian et al., under revision, JGR-Biogeosciences
7.75
CityU Hong Kong Nov 09 18
Lower Lower ppH Threatens Corals,H Threatens Corals, Coccolithophorids & Pteropods Coccolithophorids & Pteropods
Cold water corals on sill (at ~60m depth) in Knight Inlet BC(courtesy Verena Tunnicliffe, U. Victoria)
CityU Hong Kong Nov 09 1919
Carbonate (CaCOCarbonate (CaCO33) Pump -) Pump - Coccolithophorid Coccolithophorid Emiliania huxleyiEmiliania huxleyi
Image courtesy of Southampton Image courtesy of Southampton Oceanography Centre, UKOceanography Centre, UK
SEM imageSEM image
SeaWiFS ‘true SeaWiFS ‘true colour’ image colour’ image 16 July 200016 July 2000
MODIS 'true colour' image25 June 2006 (courtesy NASA)
SeaWiFS ‘true SeaWiFS ‘true colour’ image 25 colour’ image 25
April 1998April 1998
CityU Hong Kong Nov 09 20
What $$-value do we place on species What $$-value do we place on species that most people do not even know that most people do not even know
exist?exist?20
Pteropods are Pteropods are made up of made up of aragonite aragonite
CaCOCaCO33
Limacina Limacina helicinahelicina
are a food source for juvenile North Pacific salmon and also for mackerel, herring and cod.
Limacina helicina [credits: Brad Seibel]
Limacina helicina [R. Hopcroft, UAlaska]
CityU Hong Kong Nov 09 21
economic economic consequences on consequences on
commercial fisheriescommercial fisheries
C
atc
h v
alu
e,
$ M
GreensGreens - predators
YellowsYellows – primarily calcite CaCO3
RedsReds – primarily aragonite
US 2007 US 2007 FisheriesFisheries'Primary Value''Primary Value'
MollusksMollusks 19% 19%
CrustaceansCrustaceans 30% 30%
Direct Predators Direct Predators 24%24% on calcifierson calcifiers
Sum 73 %
CityU Hong Kong Nov 09 2222
Regions of Low Dissolved OxygenRegions of Low Dissolved Oxygen
Climatological mean dissolved Oxygen (mL/L) at a depth of 400 m.Climatological mean dissolved Oxygen (mL/L) at a depth of 400 m.1.15 mL1.15 mL // L L 50 µmol 50 µmol // kgkg
CityU Hong Kong Nov 09 2323
Expanding Oxygen Minimum Zones Expanding Oxygen Minimum Zones in the Tropical Oceansin the Tropical Oceans
Stramma et al., 2008, Science, 320, 655-658
OO22 at 400 m at 400 m
( (μμmol kgmol kg−1−1))
CityU Hong Kong Nov 09 2424
Expanding OExpanding O22 Minimum Zones in the Tropical Minimum Zones in the Tropical OceansOceans
Stramma et al., 2008, Science, 320.Stramma et al., 2008, Science, 320.
Data from Area
'A''A'
CityU Hong Kong Nov 09 2525
Crawford et al. 2007 Prog. Oceanogr. 75(2)Crawford et al. 2007 Prog. Oceanogr. 75(2)
Dissolved ODissolved O22 in NE Pacific in NE Pacific
% Oxygen % Oxygen SaturationSaturation
on 26.5 on 26.5 -- surfacesurface0 to 4646 to 6262 to 120
3
4
5
6
7
1956
1960
1964
1968
1972
1976
1980
1984
1988
1992
1996
2000
2004
12
P26 26.7 = -0.67 uM y-1
P4 26.7 = -1.2 uM y-1
0
50
100
150
200
250
1956
1960
1964
1968
1972
1976
1980
1984
1988
1992
1996
2000
2004
Oxy
gen
(µ
mol
kg-1)
F. Whitney, in: DFO Ocean Status Report 2006, W. Crawford (ed.)
(~170 m)
(~280 m)P426.7
OSP26.7
CityU Hong Kong Nov 09 26
Organic Matter 'OM' Organic Matter 'OM' LossLoss
C106H175O42N16P + 150150 OO22
106106 COCO22 + 16 HNO3 + H3PO4 + 78 H2O
SourceSource Dissolved nutrientsDissolved nutrients
26
Remineralization Uses ORemineralization Uses O22 & Produces & Produces COCO22 Subsurface areas of low O2 may also be areas
of high CO2 / low pH due to cumulative effect of respiration / remineralization of organic particulates by bacteria
In aerobicaerobic conditions:Equation from: Sarmiento and Gruber, Ocean Biogeochemical Dynamics, 2007.
Decreasing ODecreasing O22 in low O in low O22 regions may lead to: regions may lead to:• Hypoxia or anerobic conditions in adjacent upwelling regions
• Increasing water column denitrification in low O2 layers & sediments
• Denitrification results in N2 and NN22OO production
CityU Hong Kong Nov 09 2727
Depth of Depth of 'Corrosive' 'Corrosive' pH < 7.75 pH < 7.75 Waters on Waters on
Continental Continental ShelfShelf
Feely et al., 2008, Science
"…without the anthropogenicsignal, the equilibrium aragonite saturation level … would be deeper by about 50 m across the shelf, …"
CityU Hong Kong Nov 09 28
Dissolved oxygen profiles during the upwelling season, mid-April to mid-
October (42N to 46N)
F.Chan et al., Science 319, 920 (2008)
Recent ORecent O22 Changes off Oregon Changes off Oregon
1950-991950-99n = 3101 castsn = 3101 casts
1950-20051950-2005+ 834 casts+ 834 casts
+2006+ 220 casts
(50 (50 μμmol/kg mol/kg 1.12 1.12 mL/L)mL/L)
CityU Hong Kong Nov 09 29
The Coastal Ocean: More Hypoxia The Coastal Ocean: More Hypoxia Events?Events?
Dead zone off Newport, Oregon 2002,04,06
[www.piscoweb.org PISCO at OSU]
(50 (50 μμmol/kg mol/kg 1.12 mL/L)1.12 mL/L)
See also:Grantham et al. 2004Nature, 229, 749-753
CityU Hong Kong Nov 09 3030
How Fast Can Organisms Adapt & Evolve?How Fast Can Organisms Adapt & Evolve?
Our foodweb models need parameters that 'adapt/change' in response to changing ocean conditions:
• What is the species diversity within a functional group?
• What is the genetic diversity (plasticity) within a species?
• Is a century a long enough time for evolution via genetic mutations?
– Requires a minimum of ~25 generations??
Which species will be threatened with extinction?
ThanksThanks [email protected]
CityU Hong Kong Nov 09 31