limits to adaptation ocean acidification congressional briefing 9 november 2009 ken caldeira...
TRANSCRIPT
Limits to AdaptationOcean acidification
Congressional Briefing9 November 2009
Ken Caldeira Carnegie Institution & Stanford University [email protected]
Rain, galoshes, and limits to adaptation
To avoid getting wet, you want to bring an umbrella
To avoid climate risk, you want to reduce carbon dioxide emissions
Kasmira,2009
But to keep your feet dry, you might still need galoshes
To diminish damage from the climate change you can’t avoid, you want to improve adaptive resilience
Just wearing galoshes is not enough
emissions reduction
adaptation
Ischia, Italy
Map created by Norman Einstein
CO2 dissolving shells and skeletonsHall-Spencer / BBC
High CO2 = Invasive grasses
Low CO2
= Native shellfish
Thanks, Jason Hall-Spencer
Chemistry ofocean acidification
Formation of calcium carbonate shells and
skeletons
CO32-
CO O
OCa Ca2+ (dissolved)
H HO
H2O HC
O O
OHCO3
-C
O O
OCO3
2-
Formation of calcium carbonate shells and
skeletons
CO32-
CO O
O
Ca Ca2+ (dissolved)
H HO
H2O HC
O O
OHCO3
-C
O O
OCO3
2-
Formation of calcium carbonate shells and
skeletons
CO32-
CO O
O
Ca Ca2+ (dissolved)
H HO
H2O HC
O O
OHCO3
-C
O O
OCO3
2-
Formation of calcium carbonate shells and
skeletons
CO O
OCa CaCO3 (solid)
H HO
H2O HC
O O
OHCO3
-C
O O
OCO3
2-
Water, dissolved carbon, and shells and skeletons
CaCO3 (solid)C
O O
OCa
H HO
H2O HC
O O
OHCO3
-C
O O
OCO3
2-
Addition of CO2
CaCO3 (solid)C
O O
OCa
H HO
H2O HC
O O
OHCO3
-C
O O
OCO3
2-
CO O CO2
Formation of carbonic acid
CO O
OCa
HC
O O
OHCO3
-C
O O
OCO3
2-HH
CO O
OH2CO3
CaCO3 (solid)
Increasing ocean acidity
CO O
OCa
HC
O O
OHCO3
-C
O O
OCO3
2-H
CO O
OHCO3
-
H H+
CaCO3 (solid)
Increasing ocean acidity
CO O
OCa
HC
O O
OHCO3
-C
O O
OCO3
2-H
CO O
OHCO3
-
H H+
CaCO3 (solid)
Increasing ocean acidity
CO O
OCa
HC
O O
OHCO3
-C
O O
OCO3
2-H
CO O
OHCO3
-
H H+
CaCO3 (solid)
Increasing ocean acidity
CaCO3 (solid)C
O O
OCa
HC
O O
OHCO3
-C
O O
OCO3
2-H
CO O
OHCO3
-
H H+
Attacking a building block for shells and skeletons
CO O
OCa
HC
O O
OHCO3
-C
O O
OCO3
2-H
CO O
OHCO3
-
H H+
CaCO3 (solid)
H
Attacking a building block for shells and skeletons
CO O
OCa
HC
O O
OHCO3
-C
O O
OHCO3
-H
CO O
OHCO3
-
CaCO3 (solid)
H
Dissolving shells and skeletons
CO32-
CO O
O
HC
O O
OHCO3
-C
O O
OHCO3
-H
CO O
OHCO3
-
Ca Ca2+ (dissolved)
H
Dissolving shells and skeletons
CO32-
CO O
O
HC
O O
OHCO3
-C
O O
OHCO3
-H
CO O
OHCO3
-
Ca Ca2+ (dissolved)
H
Dissolving shells and skeletons
CO32-
CO O
O
HC
O O
OHCO3
-C
O O
OHCO3
-H
CO O
OHCO3
-
Ca Ca2+ (dissolved)
Lizard Island
ExpeditionSeptember
2008
We measured of coral skeletal growth rates 40% lower than in the late 1970’s
Distribution of corals andocean acidification
0 1 2 3 4 5
Corrosive OptimalΩAragonite
Carbon dioxide level,
Coral reef distribution
,
and chemical
conditions helping
drive reef formation
Cao and Caldeira, 2008
0 1 2 3 4 5
Corrosive OptimalΩAragoniteCao and Caldeira, 2008
Carbon dioxide level,
Coral reef distribution
,
and chemical
conditions helping
drive reef formation
0 1 2 3 4 5
Corrosive OptimalΩAragoniteCao and Caldeira, 2008
Carbon dioxide level,
Coral reef distribution
,
and chemical
conditions helping
drive reef formation
0 1 2 3 4 5
Corrosive OptimalΩAragoniteCao and Caldeira, 2008
Carbon dioxide level,
Coral reef distribution
,
and chemical
conditions helping
drive reef formation
0 1 2 3 4 5
Corrosive OptimalΩAragoniteCao and Caldeira, 2008
Carbon dioxide level,
Coral reef distribution
,
and chemical
conditions helping
drive reef formation
0 1 2 3 4 5
Corrosive OptimalΩAragoniteCao and Caldeira, 2008
Carbon dioxide level,
Coral reef distribution
,
and chemical
conditions helping
drive reef formation
Rain, galoshes, and limits to adaptation
Kasmira,2009
emissions reduction
adaptation
Adaptation is important, but it is not a substitute for emissions reduction
We need an umbrellaand galoshes
Main points
• Few and limited options for adaptation to acidification– Adaptive capacity of ecosystems can be increased by
reducing other stresses on our ocean environment (overfishing, land-based pollution, habitat loss, etc)
– Management and engineering solutions appear to be feasible only in a few isolated cases
To protect our coastal and ocean environments,
we need to greatly reduce our CO2 emissions soon
