Climate Change and EcosystemsIV Presidential Meeting

CGDD & IFHC

Sao Paulo, BrazilMarch 7, 2009

Thomas E. LovejoyThomas E. Lovejoy

Biodiversity Chair, The Heinz Biodiversity Chair, The Heinz CenterCenter

Washington, D.C.Washington, D.C.

THE H. JOHN HEINZ III CENTER THE H. JOHN HEINZ III CENTER FOR SCIENCE, ECONOMICS AND THE FOR SCIENCE, ECONOMICS AND THE ENVIRONMENTENVIRONMENT

Dr. Svante August Arrhenius 1859-1927

Source: Wallace Broecker

Analysis of a Greenlandice core oxygen isotope proxy

Image Courtesy of NASA

© WWF-Cannon / Jurgen Freund

Mountain Pine Beetle outbreaks (1959-2002)

Courtesy of Mike Bradley, Canfor Corporation

Science Magazine, November 23, 2007

IPCC Climate Change and Impact Projections

What is a “safe” level?

James Hansen,

et al., 2008

350 ppm

Fate of Anthropogenic CO2 Emissions (2000-2007)

Canadell et al. 2007, PNAS (updated)

1.5 Pg C y-1

+7.5 Pg C y-1

Atmosphere46%

4.2 Pg y-1

Land29%

2.6 Pg y-1

Oceans26%

2.3 Pg y-1

Natural CO2 Sinks absorb 55% of all Emissions

• 55% discount on human-induced climate change.

• A subsidy to the global economy worth half a trillion US$ annually if an equivalent sink had to be created (eg, EU-Emission Trading Sch.).

Canadell and Raupach 2008, Science

R.A. Houghton, unpublished

Emissions from Deforestation minus Reforestation

Pg

C y

r-1

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

1850

1860

1870

1880

1890

1900

1910

1920

1930

1940

1950

1960

1970

1980

1990

2000

Africa

Latin America

S. & SE Asia

Carbon Emissions from Land Use Change

SUM

2000-2007(Pg C y-1)

1.5

0.6

0.3

0.6

% C

O2 E

miss

ions

in

Atm

osph

ere

1960 200019801970 1990

Canadell et al. 2007, PNAS

2006

Decline in the Efficiency of CO2 Natural Sinks

Fraction of all anthropogenic emissions that stay in the atmosphere

Emissions1 tCO2

400Kg stay

Emissions1 tCO2

450Kg stay

Growth rate trend: 0.23% y−1

Efficiency of Natural Sinks

Land Fraction

Ocean Fraction

Canadell et al. 2007, PNAS

deforestation

tropicsextra-tropics

1.5

2000-2007

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Human Perturbation of the Global Carbon Budget

Global Carbon Project (2008)

PgC

deforestation

fossil fuel emissions

7.5

1.5

2000-2007

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Human Perturbation of the Global Carbon Budget

Global Carbon Project (2008)

PgC

fossil fuel emissions

deforestation

7.5

1.5

2000-2007

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Human Perturbation of the Global Carbon Budget

Global Carbon Project (2008)

PgC

fossil fuel emissions

deforestation

7.5

1.5

4.2

2000-2007

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

atmospheric CO2

Human Perturbation of the Global Carbon Budget

Global Carbon Project (2008)

PgC

atmospheric CO2

fossil fuel emissions

deforestation

ocean

7.5

1.5

4.2

2.3

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

2000-2007

Human Perturbation of the Global Carbon Budget

Global Carbon Project (2008)

PgC

atmospheric CO2

ocean

land

fossil fuel emissions

deforestation

7.5

1.5

4.2

2.32.6

2000-2007

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Human Perturbation of the Global Carbon Budget

Global Carbon Project (2008)

PgC

Over the past three centuries, ecosystems have lost 200-250 billion tons of carbon

Long atmospheric residence times

for greenhouse gases

Origin of land plants

Expansion of angiosperms

Present-day CO2

The Role of Life Processes

Planetary Engineering Using Ecosystems

CO2 PPM

Time

280

The Role of Forests

Photo courtesy USDA NRCS 

Restoring Grazing Land

Photos: United States Department of Agriculture—Natural Resources Conservation Service .

Restoring soil carbon through agriculture

Re-Greening the Emerald Planet