Considering Emissions of other non-CO2 Greenhouse Gases:Ozone-depleting substances and substitutes matter: The climate protection already achieved by the Montreal Protocol alone is far larger than the reduction target of the first commitment period of the Kyoto Protocol Velders et al., 2007 GWP-weighted emissions are ~8 GtCO2-eq./yr less than in the late 1980s

Analyses of Other Trace Gases could provide useful constraints: Photosynthesis: COS Combustion/Burning influence: acetylene, benzene, CH3Cl, CH3Br Oceanic influences: CHBr3, CH3I Other Anthropogenic Influences: Hydrocarbons, solvents Sinks: OH variability; Cl abundance: CH3CCl3, PCEGoals: 1) Supply representative and ongoing estimates of emissions from North America 2) Provide constraints to fluxes of other GHGs related to photosynthesis, fossil-fuel combustion, biomass burning, etc. For today: 1) Present some of the data and show signals related to local/regional emissions 2) Explore carbonyl sulfide (COS) as an indicator of photosynthesis

Acknowlegements

From HATS group: L. Miller, B. Miller, C. Siso, and J. Elkins

From CCGG group: A. Andrews, C. Sweeney, A. Karion, S. Wolter, J. Kofler, J. Higgs, P. Lang, K. Masarie, D. Neff, D. Guenther, and many others

Those involved in interpreting data thus far:P. Tans, J. Miller, M. Fischer, G. Petron, B. Miller, others

NACP, NOAA

Strong Greenhouse Gases:

HFCs134a152a23143a227ea125365mfc

PFC218

HCFCs22141b 142b124

CFCs111213113114115

Indicators of specific processes:

Photosynthesis: Carbonyl Sulfide Burning:Acetylene, Benzene, CH3Cl, CH3Br, (CO) Oceanic influence: CHBr3, CH3I, CH3Cl Anthropogenic input:C3-C5 HydrocarbonsPCE, CH2Cl2 Land influence:COS , CH3Cl , CHCl3 , (H2 )

Others Other ODSs Brominated gasesCS2Gases Routinely Measured in Flasks (by HATS/CCG GCMS)

Observing variability & gradients on regional scales Monitoring trace gases in 3-D Aircraft profiles Tall towers (400m) Near-surfaceAircraft (since 2004) and tall tower (since 2006-2008) networks: NOAA-carbon cycle (A. Andrews and C. Sweeney)Near-surface network: NOAA-halocarbon groupsince early 1990sSome local studies too (Colorado)

From Remote, Ground-based Surface Sites Across the GlobeMobile Air Conditioner Coolant

Aircraft data over North AmericaLarge Emission SignalsAircraft, 4 km asl

HCFC-22 vs HFC-134aAircraft data enhancement, < 3000 m, 2004-2007HCFC-22 enhancement (ppt)HFC-134a enhancement (ppt)

Aircraft data residuals

HFC-152a vs HFC-134a--residualsHFC-152a enhancement (ppt)HFC-134a enhancement (ppt)

HFC-152a vs HFC-134a aircraft

HCFC-142b vs HFC-134a residualsHFC-142b enhancement (ppt)HFC-134a

142b vs 134aall sites

Southern Sites: TGC, WKT, SCA, SGP142b vs 134aHFC-142bHFC-142bHFC-142bHFC-142bHFC-134aHFC-134aHFC-134aHFC-134a

Northern Sites: DND, LEF, NHAcma142b vs 134aScatter reflects spatial variability!HFC-142bHFC-142bHFC-142bHFC-142bHFC-134aHFC-134aHFC-134aHFC-134a

Conclusions related to non-CO2 GHGs:

An ongoing, multi-faceted sampling & measurement program is providing data for many non-CO2 GHGs from multiple sites across the U.S.

The data show large signals related to emissions, and emission variations

Inferring emissions with different techniques ongoing/planned:With 14CO2(J. Miller)With Radon(M. Fischer)With CO(S.M. et al.)With Carbon Tracker applied to other gases (G. Petron, L. Bruhwiler, K. Masarie, A. Jacobson)With back-trajectory models (STILT, FLEXPART)

Are these gases easier to apply inversions to (than CO2, CH4)?

Strong Greenhouse Gases:

HFCs134a152a23143a227ea125365mfc

PFC218

HCFCs22141b 142b124

CFCs111213113114115

Indicators of specific processes:

Photosynthesis: Carbonyl Sulfide Burning:Acetylene, Benzene, CH3Cl, CH3Br, (CO) Oceanic influence: CHBr3, CH3I, CH3Cl Anthropogenic input:C3-C5 HydrocarbonsPCE, CH2Cl2 Land influence:COS , CH3Cl , CHCl3 , (H2 )

Others Other ODSs Brominated gasesCS2Gases Routinely Measured in Flasks (by HATS/CCG GCMS)

BenzeneCH3BrCH3ClCOSCOC2Cl4CO2CH3ICHBr3F-22F-134aWesternCanada (ESP)3 Aug 2005Sampling Altitude (above sea level, km)CO2

COS as an indicator of photosynthesis:

COS uptake by vegetation: is the largest sink of this gas is modulated by stomatal conductance is catalyzed by same enzymes involved in photosynthesisVegetative emissions of COS are small (unlike CO2) potentially unique insights are possible from COS dataObservations of variability of COS and CO2 show interesting parallelsqualitatively consistent with terrestrial uptake being the main driver

COS may provide insights into gross photosynthetic uptake of carbonBut, for COS, many uncertainties remain regarding vegetative uptake, soil sink, oceanic fluxes, anthropogenic source

COS Global Budget (Gg S yr-1) (mod to Kettle et al., 2002)Net Sinks:Vegetation: 240 - 1500Soils: 130OH oxidation: 95COS photolysis (strat.): 15 O atom oxidation: 10Total sinks: 490 - 1750(total lifetime of 1.5 - 6 yr) (Kettle et al. 2002; Sandoval-Soto et al. 2005; Montzka et al. 2007)Net Sources:Oceanic: Direct:40 CS2 and DMS oxidation:240Anthropogenic: Direct:60 CS2 oxidation:120Biomass burning:90Other (wetlands):60 Total sources: 610

Fraction of Year(0.00 = Jan)COSCOS seasonal changes vs. CO2

Fit to NH only:Slope = 6 1 r2 = 0.9CO2 data fromNOAA, and B. MungerCOS and CO2 seasonal amplitudes are correlatedBroad scale variability for COS is closely related toCO2 throughout the NH

CO2A similar pattern also observed at:Northern and Eastern sites (ERUs a bit larger) If data are screened for low HCFC or HFC mixing ratios (cleanerair)

A different pattern observed at Southern sites and Western sitesFrom aircraft, Mid-west sites6 - 8 km4 6 km2 4 km< 2 km

Regional scale gradients for COS above continents likely explain the broader scale seasonal variability (as is true for CO2)

AircraftResults FromALL SITES

Color scheme:

5 to 8 km asl

2 to 5 km asl

< 2 km aslLine represents an uptake ratio of ~6

Green (HFC-134a < 5 above residual)Blue (5-10 ppt above)Red (>10 ppt above--large influence)

COS

CO2

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CO2

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CO2 (detrended; ppm)COS vs. CO2 vs. SiteColor Scheme:

Sample altitude (masl):

Green:

COS vs. Hydrogen (a gas with a strong suface sink)HydrogenCarbonyl Sulfide (ppt)Mid-WestSitesConsistent correlation observed even during July

Perhaps CO2 in July was anomalous?

C3 vs C4 photosynthesis??Or spatial variations in V(COS/CO2) ?

Recent papers on COS:

Montzka et al. 2007:Observed relationship between COS and CO2 suggests:terrestrial biosphere controls NH seasonality and abundances; in SH it is oceansuptake in NH >> CO2 GPP vs NPP uptake? COS may provide broad scale constraints on photosynthesis

Suntharalingam et al.: (in press):Quantitative analysis reaffirms importance of terrestrial ecosystem in NH and oceans in SH in controlling seasonality global budget still quite uncertain

Campbell et al.: (in press) 3-D model (US) of vertical gradients over North America during Jul-Aug:(STEM 6060km res. over US; MM5 met., CASA biosphere);

Well simulated for CO2 (Boundary conditions from TM5) For COS (NASA/UCI&NCAR(?) and NOAA data), COS well simulated only when:

FCOS = GPP * [COS]/[CO2] * V (COS/CO2)

This makes uptake by vegetation the dominant flux in model quantitative evidence that COS gradients during growing season may provide a measurement-based photosynthesis tracer

STEM model, 60x60 resolution, hourly time step, MM5 meteorologyCASA model GPP fluxV(COS/CO2) from ecosystem-based lab/mapping (mean=2.2 over domain)Biosphere fluxes at 1x1 deg gridCO2 boundary conditions from TM5

ERU = (GPP/NEE)*V(COS/CO2)ERU = V(COS/CO2)/(1 - RES/GPP)ERU is smaller in C4 cropland regionsis this because RES/GPP is different or because V is different?

Conclusions

Many other chemicals being measured that are influenced by a wide range of processes: photosynthesis, anthropogenic input, combustion, biomass burning, oceans, uptake by land. How can this additional information be appropriately used?

Despite large uncertainties on global scales, a US-scale study shows good consistency and reinforces notion that COS gradients may provide information on broad-scale photosynthesis.

Considerations:Are the role of soils constrained sufficiently?Can COS provide delineation between C4 vs C3 vegetation?Are relative leaf-based uptake rates constrained sufficiently?

Kyoto specifies regulation of gases not regulated by Montreal Protocol But once CFCs are in commerce they arent regulated by Montrealopens up potential for regulation of CFC emissions under Kyoto!! Although emissions small, perhaps significant wrt GWP-weighted emissions of these lesser abundant gases. Tightly correlated, both air-conditioning agents152a, used as a propellant in aerosol cans. Aseasonal emissions more likelyA bit more scatter in resultsFoam insulation constructionEven more scatterI like to think there is renewed interest in recent years, because the atmospheric data clearly show that this uptake signal is substantial throughout the NH atmosphere. Work by Juergen and his students, and others have pinpointed the nature of the interaction between COS and vegetationHaving a tool to be able to separate photosyn from respiration would be very useful for providing insights into carbon assimilationWhy should COS and CO2 be related?? Or show similar variations or correlations in the atmosphere? Large vegetative uptake via same enzymes involved in photosynthesis, modulated by stomata, derived from carbonic anhydrase hydrolysis, magnitude of which is currently under discussionSources: oceanic, anthropogenic, burning, BUT NO LARGE VEGETATIVE SOURCEThough sources are different small direct anthropogenic source and small terrestrial source, BUTParv, 2008 GRL: 3-D model simulation of COS and these budget corrections provided improved agreement with the NOAA global surface observations AFTER a 30S-30N aseasonal source of 235 (45% of known sources) was included to balance budget

C3 vs C4 photosynthesis