Transcript Slide - CARBOOCEAN

Seventh Carbon Dioxide Conference – Boulder, September 25-30, 2005
The Amazon and the
modern carbon cycle
Jean Ometto (1), Antonio Nobre(2) ,
Humberto Rocha(3) , Paulo Artaxo(4),
Luiz Martinelli(1)
(1)CENA/USP, (2)INPE/INPA, (3)IAG/USP, (4)IF/USP
Acknowledgments: The ICDC7 Scientific Committee
and the ICDC7 supporting agencies.
Global Carbon Budget, PgC/yr – IPCC 2001
atmospheric
change
=
fossil fuel
emissions
land-use
change
ocean
uptake
land-atm flux
terrestrial
sink
3.2
=
+6.3
+1.6 to
+3.0
-2.1
-1.0
-4.8 to
-1.6
***Data to be revised after this meeting
Nearly 20 years (1982-1999) of satellite observations of Earth’s vegetation
reveal increase of the overall productivity of land plants by 6 % Nemani (2003)
Ecosystem
Area
(106) km2
NPP
(PgC/yr)
Plant C
(Pg)
Soil C
(Pg)
Tropical for.
17.5
10.4
13.7
5.6
2.8
13.5
27.6
20.1
7.4
2.4
0.5
1.3
3.8
13.7
340
139
57
2
17
4
79
692
262
150
144
124
248
345
15.0
27.7
5.1
3.2
6
10
172
208
Temper. for.
Boreal for.
Artic tundra
Med.shrub.
Crops
Trop.savan.
Temp.sava
n
Deserts
Sabine et al. (2004) – SCOPE 62
Amazon alone:
21% of tropical forest
4% of the area of Earth
~6 PgC/yr NPP
11% of plant C of world
70 Pg of C in plant
(Houghton et al. 2001)
60
120%
50
100%
40
80%
30
60%
20
40%
10
20%
0
0%
100 150 200 250 300 350 400 More
AGLB (ton/ha)
Houghton et al. (2001):
44 sites - 269±86 ton/ha
Cumulative percentage
Frequency
Above ground biomass
•Baker et al. (2003)
59 sites
t0 = 282±57 ton/ha
t7 = 294±55 ton/ha
•Overall AGB average:
283±66 ton/ha
Total biomass
Houghton et al. (2001):
AGB + 30% (roots and
dead AGB): 370 ton/ha
Manaus-K34
Flona-Santarem
LBA Flux Towers
Fazenda NS
Aparecida
Reserva Jaru
Caxiuana
Pantanal
Brasilia-Cerrado
Estimates of net ecosystem exchange (NEE) obtained by eddy
covariance technique and by aboveground biomass estimates.
Biomass inventory (Backer et al, 2004), eastern and central
plots, western plots and floodplain plots, respectively
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(
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ps
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ili
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.(
95
)
NEE (tonC/ha.yr)
2
1
0
-1
-2
-3
-4
-5
-6
CO2 boundary layer budget
SINK
Integrated eddy covariance flux (mol m-2)
-0.4
Night fluxes are
higher in budget
study
-0.3
-0.2
-0.1
0.3
0.2
0.1
-0.1
-0.2
-0.3
-0.4
0.1
0.2
0.3
SOURCE
0.4
Integrated boundary layer budget flux (mol C m-2)
A comparison of estimates of the Amazonian forest carbon budget as
obtained by CBL budgeting and the eddy covariance methods for
Manaus in July 2001. Square symbols represent night time periods and
circles represent daytime the daytime period. (Jon Lloyd et al)
The role of tropical rivers in the global Carbon budget
Richey et al (2002)
Integrating field pCO2 measurements and flooded areas
1.77 x 106 km2
25
25
%
T (>100m)
20
15
20
10
15
10
S (<100 m)
5
MF
CO2 Evasion (Tg C mo-1)
Flooded Area (x 104 km2)
Inundation
30
25
20
15
10
5
MC
0
J
F
M
A
M
J
0
J
A
S
O
N
D
MC
J
F
M
A
M
J
J
A
S
O
N
D
Richey et al (2002)
: 1.2 ± 0.3 Mg C ha-1 y-1 (basin ~ 0.5 Pg/y)
13 x Fluvial TOC export = 0.036 Pg C /y
Methane emissions from wetlands
2.5
annual methane emission, Tg C y
-1
Mainstem
Emissions
2.0
High
Interannual
Variability
Central Amazon Basin
(1.77 million km2)
Methane Emission 6.8 + 1.3 Tg C y-1
1.5
Mid
1.0
Low
0.5
Lowland Amazon Basin (<500 m asl)
(5.19 million km2)
Methane Emission 22 Tg C y-1
0.0
Final estimates suggest that the Amazon Basin wetlands may produce as
much as 20% of the natural global source of methane. (Melack et al., 2004)
Global Carbon Budget, PgC/yr – IPCC 2001
atmospheric
change
=
fossil fuel
emissions
land-use
change
ocean
uptake
land-atm flux
terrestrial
sink
3.2
=
+6.3
+1.6 to
+3.0
-2.1
-1.0
-4.8 to
-1.6
Flux of carbon (PgC/yr) due to land use changes in the tropics
estimated by different methods and authors.
Houghton et
al. (2000)
Amazon
Fearnside
(2001)
Houghton et
al. (2003)
DeFries et
al. (2002)
Archard et
al. (2003)
Gurney et al.
(2002)
+0.18 +0.26
Tropical
America
+0.75 +0.43
Total Tropics
+2.20 +0.91 +0.96 +1.20
Method
FAO data
Satellite
Tropical
America
24-35%
42-60%
Total Tropics
8-12%
20-29%

Inversion
15-22%
The combined effects of clear-cutting, forest regrowth on
abandoned land, and logging in the 1990’s may have released
equivalent to 10 to 25% of global, human-induced emissions.
Deforestation and fire spots in Amazonia
Fire Spots in Amazônia
1999 - 2004 (NOAA-12)
Deforestation (km 2 /y)
Amazonia Deforestation
1977- 2004 ( km² /y )
35000
180000
30000
160000
140000
25000
120000
20000
100000
80000
15000
60000
10000
40000
5000
20000
0
77
/8
8*
88
/8
9
89
/9
0
90
/9
1
91
/9
2
92
/9
4
94
/9
5
95
/9
6
96
/9
7
97
/9
8
98
/9
9
99
/0
0
00
/0
1
01
/0
2
02
/0
3
03
/0
4
0
* decadal annual mean
INPE, 2005
1999
2000
2001
2002
2003
2004
Deforestation in Amazon Basin
Source: Daniel Nepstad / IPAM
Some aspects related to LUC
• Agricultural “Frontier”; In several regions
development is associated to expansion;
• Socio-Economic drivers:
– Pressure from large scale agricultural crops ~ soy
bean, sugar cane and others
– Pastures, logging
– Road construction
• Pressure from increase of population;
Critical aspects to reduce uncertainties in carbon
balance estimates for the Amazon Region
Eddy Covariance

Flux measurements
ABL/FT
Radon
Flux/Concentration

Modeling
River/Floodplains
Measurements

Biomass
Deforestation
Estimates of net exchange of CO2, CH4 and N2O from the Amazon
Basin to the atmosphere
Davidson and Artaxo, 2004
In terms of GWP, the combined impacts of sources and sinks in
Amazonia is close to zero