Recent Carbon Trends and the Global Carbon Budget

updated to 2006

GCP-Global Carbon Budget team:Pep Canadell, Philippe Ciais, Thomas Conway, Chris Field, Corinne Le Quéré, Skee Houghton,

Gregg Marland, Mike Raupach, Erik Buitenhuis, Nathan Gillett

Last update: 13 June 2008

Outline

1. Recent global carbon trends (2000-2006)

2. The perturbation of the global carbon budget (1850-2006)

3. The declining efficiency of natural CO2 sinks

4. Attribution of the recent acceleration of atmospheric CO2

5. Conclusions and implications for climate change

1. Recent global carbon trends

FAO-Global Resources Assessment 2005; Canadell et al. 2007, PNAS

Tropical Americas 0.6 Pg C y-1

Tropical Asia 0.6 Pg C y-1

Tropical Africa 0.3 Pg C y-1

2000-2005

Tropical deforestation

13 Million hectares each year

Anthropogenic C Emissions: Land Use Change

1.5 Pg C y-1

Born

eo, C

ourte

sy: V

iktor

Boe

hm

Houghton, unpublished

Carbon Emissions from Tropical DeforestationP

g C

yr-1

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.8018

50

1860

1870

1880

1890

1900

1910

1920

1930

1940

1950

1960

1970

1980

1990

2000

Africa

Latin America

S. & SE Asia

Anthropogenic C Emissions: Land Use Change

SUM

2000-2006

1.5 Pg C y-1

(16% total emissions)

Anthropogenic C Emissions: Fossil Fuel

Raupach et al. 2007, PNAS; Canadell et al 2007, PNAS

1990 - 1999: 1.3% y-1

2000 - 2006: 3.3% y-1

0

1

2

3

4

5

6

7

8

9

1850 1870 1890 1910 1930 1950 1970 1990 2010

Fo

ssil

Fu

el E

mis

sio

n (

GtC

/y) Emissions

280

300

320

340

360

380

400

1850 1870 1890 1910 1930 1950 1970 1990 2010

1850 1870 1890 1910 1930 1950 1970 1990 2010

2006 Fossil Fuel: 8.4 Pg C[2006-Total Anthrop. Emissions:8.4+1.5 = 9.9 Pg]

Trajectory of Global Fossil Fuel Emissions

Raupach et al. 2007, PNAS

SRES (2000) growth rates in % y -1 for 2000-2010:

A1B: 2.42 A1FI: 2.71A1T: 1.63A2: 2.13B1: 1.79B2: 1.61

Trajectory of Global Fossil Fuel Emissions

Raupach et al. 2007, PNAS

SRES (2000) growth rates in % y -1 for 2000-2010:

A1B: 2.42 A1FI: 2.71A1T: 1.63A2: 2.13B1: 1.79B2: 1.61

Observed 2000-2006 3.3%

Carbon Intensity of the Global Economy

Canadell et al. 2007, PNAS

Carb

on in

tens

ity

(KgC

/US$

)Kg Carbon Emitted

to Produce 1 $ of Wealth

1960 1970 1980 1990 2000 2006

Phot

o: C

SIRO

Raupach et al 2007, PNAS

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

1980

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

1980

World

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

1980 1985 1990 1995 2000 2005

F (emissions)P (population)g = G/Ph = F/G

Fact

or (r

elat

ive to

199

0)

EmissionsPopulationWealth = per capita GDPCarbon intensity of GDP

Drivers of Anthropogenic Emissions

Regional Pathways (Kaya identity)

C emissions

Population

C Intensity

Developed Countries (-)

Developing Countries Least Developed Countries

Wealth pc

Raupach et al 2007, PNAS

Raupach et al. 2007, PNAS

CumulativeEmissions

[1751-2004]

Fluxin 2004

FluxGrowthin 2004

Populationin 2004

0%

20%

40%

60%

80%

100% D3-Least Developed Countries

India

D2-Developing Countries

ChinaFSU D1-Developed CountriesJapanEU

USA

Anthropogenic C Emissions: Regional Contributions

2000 - 2006: 1.9 ppm y-1

1970 – 1979: 1.3 ppm y-1

1980 – 1989: 1.6 ppm y1

1990 – 1999: 1.5 ppm y-1

Year 2007Atmospheric CO2

concentration:

382.6 ppm35% above pre-industrial

NOAA 2007; Canadell et al. 2007, PNAS

Atmospheric CO2 Concentration 0

1

2

3

4

5

6

7

8

9

1850 1870 1890 1910 1930 1950 1970 1990 2010

280

300

320

340

360

380

400

1850 1870 1890 1910 1930 1950 1970 1990 2010

Atm

oap

her

ic [

CO

2]

(pp

mv)

[CO2]

2 ppm/year

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1850 1870 1890 1910 1930 1950 1970 1990 2010

1850 1870 1890 1910 1930 1950 1970 1990 2010

[CO2]

2. The perturbation of the global

carbon cycle (1850-2006)

deforestation

tropicsextra-tropics

1.5

2000-2006

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Perturbation of Global Carbon Budget (1850-2006)

Le Quéré, unpublished; Canadell et al. 2007, PNAS

deforestation

fossil fuel emissions

7.6

1.5

2000-2006

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Perturbation of Global Carbon Budget (1850-2006)

Le Quéré, unpublished; Canadell et al. 2007, PNAS

fossil fuel emissions

deforestation

7.6

1.5

2000-2006

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Perturbation of Global Carbon Budget (1850-2006)

Le Quéré, unpublished; Canadell et al. 2007, PNAS

fossil fuel emissions

deforestation

7.6

1.5

4.1

2000-2006

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

atmospheric CO2

Perturbation of Global Carbon Budget (1850-2006)

Le Quéré, unpublished; Canadell et al. 2007, PNAS

atmospheric CO2

fossil fuel emissions

deforestation

ocean

7.6

1.5

4.1

2.2

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

2000-2006

Perturbation of Global Carbon Budget (1850-2006)

Le Quéré, unpublished; Canadell et al. 2007, PNAS

atmospheric CO2

ocean

land

fossil fuel emissions

deforestation

7.6

1.5

4.1

2.22.8

2000-2006

CO2 f

lux

(Pg

C y-1

)Si

nkSo

urce

Time (y)

Perturbation of Global Carbon Budget (1850-2006)

Le Quéré, unpublished; Canadell et al. 2007, PNAS

Canadell et al. 2007, PNAS

Perturbation of the Global Carbon Budget (1959-2006)

CO2 f

lux

(Pg

CO2 y

-1)

Carb

on fl

ux (P

g C

y-1)

Carb

on in

tens

ity

(KgC

/US$

)Si

nkSo

urce

Time (y)

3. The declining efficiency of

natural sinks

Fate of Anthropogenic CO2 Emissions (2000-2006)

Canadell et al. 2007, PNAS

1.5 Pg C y-1

+7.6 Pg C y-1

Atmosphere45%

4.1 Pg y-1

Land30%

2.8 Pg y-1

Oceans25%

2.2 Pg y-1

Climate Change at 55% Discount

Natural sinks absorb 5 billions tons of CO2 globally every year, or 55% of all anthropogenic carbon emissions.

Canadell et al. 2007, PNAS

Natural Sinks: Large Economic Subsidy

Natural sinks are a huge subsidy to our global economy worth half a trillion Euros annually if an equivalent sink had to be created using other climate mitigation options (based on the cost of carbon in the EU-ETS).

Canadell & Raupach 2008, Science

1. The rate of CO2 emissions.

2. The rate of CO2 uptake and ultimately the total amount of C that can be stored by land and oceans:

– Land: CO2 fertilization effect, soil respiration, N deposition fertilization, forest regrowth, woody encroachment, …

– Oceans: CO2 solubility (temperature, salinity),, ocean currents, stratification, winds, biological activity, acidification, …

Factors that Influence the Airborne Fraction

Canadell et al. 2007, Springer; Gruber et al. 2004, Island Press

% 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 anthropogenic emissions that stay in the atmosphere

Emissions1 tCO2

400Kg stay

Emissions1 tCO2

450Kg stay

Efficiency of Natural Sinks

Land Fraction

Ocean Fraction

Canadell et al. 2007, PNAS

• Part of the decline is attributed to up to a 30% decrease in the efficiency of the Southern Ocean sink over the last 20 years.

• This sink removes annually 0.7 Pg of anthropogenic carbon.

• The decline is attributed to the strengthening of the winds around Antarctica which enhances ventilation of natural carbon-rich deep waters.

• The strengthening of the winds is attributed to global warming and the ozone hole.

Causes of the Declined in the Efficiency of the Ocean Sink

Le Quéré et al. 2007, Science

Cred

it: N

.Met

zl, A

ugus

t 200

0, o

cean

ogra

phic

crui

se O

ISO

-5

Angert et al. 2005, PNAS; Buermann et al. 2007, PNAS; Ciais et al. 2005, Science

Drought Effects on the Mid-Latitude Carbon Sinks

Summer 1982-1991

Summer 1994-2002/04

NDVI Anomaly 1982-2004[Normalized Difference Vegetation Index]

A number of major droughts in mid-latitudes have contributed to the weakening of the growth rate of terrestrial carbon sinks in these regions.

4. Attribution of the recent

acceleration of atmospheric CO2

65% - Increased activity of the global economy

Canadell et al. 2007, PNAS

17% - Deterioration of the carbon intensity of the global economy

18% - Decreased efficiency of natural sinks

2000 - 2006: 1.9 ppm y-1

1970 – 1979: 1.3 ppm y-1

1980 – 1989: 1.6 ppm y1

1990 – 1999: 1.5 ppm y-1

Attribution of Recent Acceleration of Atmospheric CO2

To:• Economic growth• Carbon intensity• Efficiency of natural sinks

5.

Conclusions and implications for climate change

• The growth of carbon emissions from fossil fuels has tripled compared to the 1990s and is exceeding the predictions of the highest IPCC emission scenarios.

Conclusions (i)

• Atmospheric CO2 has grown at 1.9 ppm per year (compared to about 1.5 ppm during the previous 30 years)

• The carbon intensity of the world’s economy has stopped decreasing (after 100 years of doing so).

Since 2000:

Conclusions (ii)

• The efficiency of natural sinks has decreased by 10% over the last 50 years (and will continue to do so in the future), implying that the longer we wait to reduce emissions, the larger the cuts needed to stabilize atmospheric CO2.

• All of these changes characterize a carbon cycle that is generating stronger climate forcing and sooner than expected.

• Angert A, Biraud S, Bonfils C, Henning CC, Buermann W, Pinzon J, Tucker CJ, Fung I (2005) PNAS 102:10823-10827.

• Breshears DD, Cobb NS, Richd PM, Price KP, Allen CD (2005) PNAS 42:15144-15148.• Canadell JG, Corinne Le Quéré, Michael R. Raupach, Christopher B. Field, Erik T. Buitehuis,

Philippe Ciais, Thomas J. Conway, NP Gillett, RA Houghton, Gregg Marland (2007) PNAS.• Canadell JG, Pataki D, Gifford R, Houghton RA, Lou Y, Raupach MR, Smith P, Steffen W

(2007) in Terrestrial Ecosystems in a Changing World, eds Canadell JG, Pataki D, Pitelka L (IGBP Series. Springer-Verlag, Berlin Heidelberg), pp 59-78.

• Ciais P, Reichstein M, Viovy N, Granier A, Ogée, J, V. Allard V, Aubinet M, Buchmann N, Bernhofer Ch, Carrara A, et al. (2005) Nature 437:529-533. Raupach MR, Marland G, Ciais P, Le Quéré C, Canadell JG, Klepper G, Field CB, PNAS (2007) 104: 10288-10293.

• Global Forest Resource Assessment (2005) FAO Forestry Paper 147.• Gruber N, Friedlingstein P, Field CB, Valentini R, Heimann M, Richey JF, Romero P, Schulze

E-D, Chen A (2004) in Global Carbon Cycle, integrating human, climate, and the natural world, Field CB, Raupach M (eds). Island Press, Washington, DC., pp 45-76

• Le Quéré C, Rödenbeck C, Buitenhuis ET, Thomas J, Conway TJ, Langenfelds R, Gomez A, Labuschagne C, Ramonet M, Nakazawa T, Metzl N, et al. (2007) Science 316:1735-1738.

• Canadell JG, Raupach MR (2008) Forest management for climate change mitigation. Science 320, 1456-1457, doi: 10.1126/science.1155458.

References

www.globalcarbonproject.org info@globalcarbonproject.org