Ocean acidification

• is occurring

• negative impacts climate

• negative impacts fisheries

Sybil Seitzinger

Executive Director, IGBP

www.IGBP.net

Ocean acidification

(Feely et al., 2008) •*

Atmos CO2

seawater CO2

pH

Ocean acidification

• is occurring

• negative impacts climate

• negative impacts fisheries

29%

26%

45%

Fate of anthropogenic CO2 emissions (2000-2008)

Le Quéré et al. 2009, Nature geoscience; Canadell et al. 2007, PNAS, updated

+

Climate & ocean acidification

• CO2 dissolves sw

• decreases with pH

Climate & ocean acidification

• CO2 dissolves sw

• decreases with pH

• Organisms remove CO2

• make biomass

• calcium carbonate shells

Coccolithophores

NASA image

E. huxleyi

G. oceanica

C. braarudii

C. quadriperforatus

Coccolithophores largest producer of calcite on Earth

Ambient pH

Riebesell et al. 2000Langer et al. 2006

pH disrupts shell formation

NASA image

E. huxleyi

G. oceanica

C. braarudii

C. quadriperforatus

Coccolithophores largest producer of calcite on Earth

Ambient pH pH

Riebesell et al. 2000Langer et al. 2006

Ocean acidification

• is occurring

• negative impact climate

• negative impacts fisheries

Decreasing pHRies et al. 2009Cooley and Doney 2009

Ocean acidification slows shell calcification

• economic losses

• global shellfish prod. 10.5 billion US$

• disruption livelihoodsN

et c

alci

fica

tio

n r

ate

(wt%

per

60

d)

International coordination

www.imber.info

• standardize methods• coordinate field campaigns• synthesis

Summary for Policymakers

Ocean acidification

• is occurring

• negative impacts climate

• negative impacts fisheries

Still much to be learned!

Sybil Seitzinger

Executive Director, IGBP