Regional scale N2O fluxes in eastern and central Amazônia:

2001 - 2007

Monica T.S. D’AmelioLuciana Vanni Gatti

John B. MillerPieter Tans

Outline

• Vertical profile samples

• N2O Flux Calculation

• Enhancement of N2O since 2004

• N2O Flux seasonality

• CO x N2O

• N2O is the 3rd most important anthropogenic greenhouse gas

• Life time: 120 years• Global Warming

Potential: 300 (100-years time-horizon)

In 1750270ppb

Source N2O (AR4) Anthropogenic sources Fossil fuel combustion & industrial processes 0.7 aircraft -- Agriculture 2.8 Biomass and biofuel burning 0.7 Human excreta 0.2 River, esturies, coastal zones 1.7 Atmospheric deposition 0.6 Anthropogenic total 6.7 Natural sources Soils under natural vegetation 6.6 Oceans 3.8 Lightning -- Atmospheric chemistry 0.6 Natural total 11.0 Total sources 17.7

Sample Sites: SAN, MAN

4 - 5 km

SAN: Dec 2000 - Dec 2008MAN: Dec 2004 - Dec 2007

NOAA: 2000-2003IPEN: 2004-2008Gases: CO2, CH4, CO, H2, N2O, SF6

Regional scale

Methodology of Calculation

Flux calculation

Barbados(RPB)

Ascension(ASC)

SANMAN FLOW

time

)O][N-O]([N

F

4km

0z

bg2site2

ON2

dz

Miller et al., 2007 method

Trajectories Study (Hysplit model)

Very Large Flux Chamber

FTL

Back-trajectory – Hysplit model

Background calculation

ASCASCRPBRPBbgON CfCfC )(2

?

Defining tracer gas

‘No’ Emissions

2x105

SF6 = Tracer gas

SF6 Time Series

4.4

4.8

5.2

5.6

6.0

6.4

9/11/2000 9/6/2001 9/1/2002 8/27/2003 8/21/2004 8/16/2005 8/11/2006 8/6/2007

SF

6 M

ixin

g R

atio

(p

pt)

ASC RPB SAN MAN FTL

Background calculation

ASCASCRPBRPBbgON CfCfC )(2

SF6 Time Series

4.4

4.8

5.2

5.6

6.0

6.4

9/11/2000 9/6/2001 9/1/2002 8/27/2003 8/21/2004 8/16/2005 8/11/2006 8/6/2007

SF

6 M

ixin

g R

atio

(p

pt)

ASC RPB SAN MAN FTL

SF6 Time Series

4.4

4.8

5.2

5.6

6.0

6.4

9/11/2000 9/6/2001 9/1/2002 8/27/2003 8/21/2004 8/16/2005 8/11/2006 8/6/2007

SF

6 M

ixin

g R

atio

(p

pt)

ASC RPB SAN MAN FTL

ASCRPB

RPBASC

RPBSANASC

ff

CC

CCf

1

Results

N2O Time seriesN2O Time series

314

316

318

320

322

324

9/11/2000 10/16/2001 11/20/2002 12/25/2003 1/28/2005 3/4/2006 4/8/2007 5/12/2008

N2O

Mix

ing

Rat

io (

pp

b)

ASC RBP SAN above MAN above FTL

(a)

N2O Time series

314

316

318

320

322

324

9/11/2000 10/16/2001 11/20/2002 12/25/2003 1/28/2005 3/4/2006 4/8/2007 5/12/2008

N2O

Mix

ing

Rat

io (

pp

b)

Ascension Barbados SAN below MAN below

(b)

Above 1200mBefore 20040.1 ppbAfter 20040.7 ppb

Below 1200mBefore 20040.3 ppb After 20040.9 ppb

Normalized Profiles

Vertical Profiles

0

500

1000

1500

2000

2500

3000

3500

4000

4500

316.0 317.0 318.0 319.0 320.0 321.0 322.0 323.0N2O mixing ratio (ppb)

Alt

itu

de

(m)

a Normalized Profiles

0

500

1000

1500

2000

2500

3000

3500

4000

4500

-1.0 0.0 1.0 2.0 3.0N2O mixing ratio (ppb)

Alt

itu

de

(m)

2001

2002

2003

2004

2005

2006

b

From Coast to SAN

-4.0-3.0-2.0-1.00.01.02.03.04.05.06.0

0 1 2 3 4 5 6 7 8 9 10 11 12months

N2O

Flu

x (m

gN

2O

/m2/d

ay)

2000 (2) 2001 (8) 2002 (3) 2003 (6)2004 (8) 2005 (7) 2006 (10) 2007 (15)

(a)

From Coast to MAN

-4.0-3.0

-2.0-1.00.01.0

2.03.04.0

5.06.0

0 1 2 3 4 5 6 7 8 9 10 11 12months

Flu

x N

2O

(m

gN

2O

/m2/d

ay)

2004 (1) 2005 (10) 2006 (8) 2007 (10)

(b)

0

100

200

300

400

500

600

700

1 2 3 4 5 6 7 8 9 10 11 12

rain

fall

(m

m)

SAN

MAN

Other sites

(c)

FSAN = 1.5 mgN2O/m²/yr

FMAN = 2.1 mgN2O/m²/yr

N2O x CO - SAN01/06/05

0

500

1000

1500

2000

2500

3000

3500

4000

4500

318.8 319 319.2 319.4 319.6 319.8

ppb N2O

60 110 160 210 260 310

ppb CO12/21/00

0

500

1000

1500

2000

2500

3000

3500

4000

316 316.5 317 317.5 318

ppb N2O

95 115 135 155ppb CO

Ratio CO/N2O 229 molCO/molN2O (coast to SAN)Andreae and Merlet 817 molCO/molN2O (tropical forest)

Ecosystem/Location Period Season Flux(mgN2Om-2 day-1) Global-scale GEIA tropical land¹ 1990 Annual 0.95 Hirsch et al. tropical land¹ 1998 – 2001 Annual 1.54 ± 0.55 GEIA South America¹ 1990 Annual 1.55 Hirsch et al. South America¹ 1998 – 2001 Annual 2.50 ± 0.89 Hirsch et al.South America ¹ 2002 – 2005 Annual 1.6 ± 0.5 (?)

Regional-scale Coast to SAN² 2001-2007 Wet 1.42 ± 1.62 Coast to SAN² 2001-2007 Dry 1.62 ± 1.69 Coast to MAN² 2004-2007 Wet 2.73 ± 1.15 Coast to MAN² 2004-2007 Dry 1.94 ± 1.56

Plot-scale PF Porto Velho, RO3 1992-1999 Wet; Dry (1.5 ± 0.4); (2.3 ± 0.4) PF Jamari, RO3 1992-1999 Wet; Dry (3.4 ± 1.0); (1.6 ± 0.4) PF Caucalândia, RO3 1992-1999 Wet; Dry (2.6 ± 0.4); (2.5 ± 0.4) PF Manaus, AM4 1992-1999 Annual 0.4 PF SAN, PA5a 2001-2002 Annual 1.3 ± 0.2 PF SAN, PA5b 2001-2002 Annual 2.2 ± 0.9 PF Santarém, PA6 1999/2000 Annual 2.9 – 4.1 PF Nova Vida, RO7 2001 Annual 4.0 ± 0.8 YP RO4 1992-1999 Annual 2.7 – 4.34 YP Nova Vida, RO7 2001 Annual 0.2 ± 0.1 OP RO4 1992-1999 Annual 0.1 – 0.3 TA Nova Vida, RO7 2001 Annual 0.6 ± 0.3

1.7

1.9

1.9

Summary

• Simple transport model, but calibrated with SF6 measurements.

• Enhancement of N2O mixing ratio since 2004

• N2O Flux seasonality from coast to SAN and less seasonality from coast to MAN

• From coast to SAN – wet, dry high fluxes

• CO x N2O: no clear pattern

Acknowledged