Biomass Burning Emissions over Southern Africa

 

Summary of Deliberations

Data-Analysis Workshop

University of Virginia

3 to 5 November 2001

 

Draft Prepared by Bill Keene and Jürgen Lobert

7 November 2001

 

 

Attendees

 

Paul Crutzen, Max Planck Institute for Chemistry and Scripps Institution of Oceanography

Christelle Hely, University of Virginia

Rupert Holzinger, Max Planck Institute for Chemistry

Christof Jost, Max Planck Institute for Chemistry

Bill Keene, University of Virginia

Stefania Korontzi, University of Maryland

Tobias Landman, University of Witwatersrand

Jürgen Lobert, Advanced Pollution Instrumentation

John Maben, University of Virginia

Bob Swap, University of Virginia (attended 5 November only)

 

 

The meeting involved four main activities:

 

1.      Reviews of the project’s objectives, research plan, and operations to date (biofuels sampled and analyzed, types of burns, etc.); most of this information is available through the project web site (http://jurgenlobert.net/projects/mpi_safari/).  

 

2.      Reports on the status of individual components of the project including preliminary data analyses and model calculations, schedules for posting outstanding data, and related issues involving data quality. 

 

3.      Resolution of possible mechanisms and timeframes for integrating results from the burning experiments in Mainz with those from other components of SAFARI to quantify regional emissions.

 

4.      General discussion with Bob Swap concerning the status of the larger SAFARI effort and related future plans.

 

 

Status of Data Availability from Workshop Participants and Collaborators

 

Characteristics of biofuels sent to MPI (water content, species composition, etc.)

            Lead PIs – Bill Keene, UVA / Jürgen Lobert, API

            Status – preliminary data posted

 

Elemental composition of biofuels and ash

            Lead PIs – Bill Keene / John Maben, UVA

            Measurement techniques

                        C, N – Carlo Erba elemental analyzer

                        Cl, Br, I, S, P – Parr Bomb digest, ion chromatography

                        Ca, K – Parr Bomb digest, AA spectroscopy

            Status

                        Biofuel C, N, Cl, Br, I, S, P, - preliminary data posted

                        Biofuel Ca, K – not yet available; to be posted in about 1 month

                        Ash C, N – preliminary data posted

                        Ash Cl, Br, I, S, P – preliminary data available; to be posted within a week

                        Ash Ca, K – not yet available; to be posted in about 1 month

 

CO, CO2, NOx, physical burn data (fuel mass, exhaust through stack, temperature, etc.)

            Lead PI – Jürgen Lobert, API

            Measurement techniques

                        CO, CO2, NOx - continuous infrared and chemiluminescence analyzers

                        Physical data - various methods

            Status

                        CO, CO2, NOx - preliminary data posted

                        Physical data - preliminary data posted

 

Methylhalids, other halogenated organics, CH4, N2O

            Lead PI – Jürgen Lobert, API

            Measurement Techniques

                        Methyl halides and other compounds - GC/MS

                        CH4 - GC/FID; N2O - GC/ECD

            Status

                        Methyl halides - preliminary data to be posted within a month

                        CH4, N2O - preliminary data to be posted within a month

                        Other compounds - not yet available, to be posted within 3 months

 

Soluble reactive trace gases (HCl, SO2, NH3, HONO, CH3COOH, HCOOH

            Lead PI – Bill Keene / John Maben, UVA

            Measurement technique

                        Sampled with tandem mist chambers

                        Analyzed by ion chromatography

            Status – preliminary data posted

 

Volatile inorganic Cl, Br, and I

            Lead PI – Bill Keene / John Maben, UVA

            Measurement technique

                        Sampled with hi-vol filterpacks

                        Analyzed by ion chromatography

            Status – preliminary data posted

 

Composition of particles

Lead PI – Bill Keene / John Maben, UVA

            Measurement technique

                        Sampled in bulk on quartz-fiber filter

                        C, N – Carlo Erba elemental analyzer

                        Cl, Br, I, S, P – Parr Bomb digest, ion chromatogaphy

                        Ca, K – Parr Bomb digest, AA spectroscopy

                        Cl-, NO3- , SO42- - Extracted in deionized water, ion chromatography

                        NH4+, Ca2+, K+, Na+, Mg2+ - extracted in deionized water, AA spec.

            Status

                        Ionic composition – not yet available; to be posted in about 2 months

                        Elemental composition – not yet available; to be posted in about 3 months

 

Volatile organics

            Lead PI – Rupert Holzinger, MPI

            Measurement technique – PTR-MS

            Status – preliminary data available; to be posted in about 1 month

 

Acetone, acetonitile, SO2

                Lead PI – Christof Jost, MPI

                Measurement technique – AP-CIMS

            Status – preliminary data available; to be posted in about 1 month

 

Elemental mercury in biofuel and ash

            Lead PI – Hans Friedli, NCAR

            Measurement technique - unknown

            Status – preliminary data available, to be posted within a week.

 

Organic properties and physical characteristics of bulk aerosol

            Lead PI – Olga Mayol-Bracero / Pascal Guyon, MPI

            Measurement techniques - unknown

            Status – unknown

 

Detailed analysis of fuel loads, areas burned , and C emissions in area of Kruger Park

            Lead PI – Tobias Landman, U. Witwaterstrand

            Status

                        Work in progress

                        Complete preliminary analysis available by about May 02

 

Detailed analysis of fuel loads, areas burned , and C emissions near Mongu, Zambia

            Lead PI – Christelle Hely, UVA

            Status – Complete; draft manuscript submitted for publication, available in mid-December

 

Fuel-load model along transect from Etosha to Zambia

            Lead PI – Christelle Hely, UVA

            Status – In progress; available by about February 02

 

C-emissions model for southern Africa

            Lead PI – Stefania Korontzi / Chris Justice, UMD and UVA

            Status

                        Version 1 hopefully by spring 02

                        Final version by summer/autumn 02

 

 

Data Required for Regional Extrapolation of Emissions

 

1)      Area Burned

Estimated from MODIS with Landsat validation

Sources

            David Roy (regional) – Dec 01

            Stefania Korontzi (regional) – Spr 02 (preliminary)

 

2)      Fuel Load

             Modeled and validated

            Sources

                        Bob Scholes (regional) – Dec 01

                        Christelle Hely (regional) – Feb 02 (probably better quality)

 

3)      Combustion Completeness (percentage of burned fuel)

Modeled with ground truthing

Sources

            Tobias Landman (Kruger area) – Spr 02

            Christelle Hely (Zambia) - available

            Stephania Korntzi (regional) – Spr 02 (preliminary)

 

4)      Combustion Efficiency (relative percentages of CO and CO2, e.g., modified combustion efficiency, MCE)

Measured during experimental burns in Mainz

            Jürgen Lobert – available

Measured during specific burns in field

            C130

            U Washington

            Others?

Modeled and validated

            Stefania Korontzi (regional) – Spr 02 (preliminary)

5)      Emission Factors

Measured during experimental burns in Mainz

            Scripps/UVA/MPI group (availability see above)

Measured in field during specific burns

            C130

            U. Washington

            Others?

Modeled (C only)

            Stefania Korontzi – Spr 02 (prelininary)

 

 

Issues / Action Items

 

1)      Bias in acetone and acetonitrile measured with PTR-MS and AP-CIMS.

Measurements in ambient air and cal-gas streams agree

Measurements in burn emissions differ systematically by 30% to 100% (PTR-MS is higher)

Detailed testing to date indicates no obvious cause

Action – Holzinger and Jost will continue to try to resolve nature of bias

 

2)      Bias in SO2 measured by Keene/Maben and Jost

SO2 measured with mist-chamber technique is systematically higher than that measured by AP-CIMS (by up to an order of magnitude)

Possible causes

-         Wall losses (mist-chamber data account for up to 25% losses in 1.2 m inlet; losses in longer AP-CIMS inlet line were not quantified)

-         Sources of SO42- in mist solutions other than SO2; e.g.,  

Oxidation of SO2 to H2SO4 in inlet

Other S gases that react to form SO42- in mist solutions

-         Positive bias in estimating SO2 from integrated mist-chamber sampling (e.g., divergence between SO2 concentration and flux in exhaust gas)

Action – Jost and Keene will quantify differences and continue to try to resolve nature of bias

 

3)      Bias in CH3COOH measured by Keene/Maben and Holzinger

CH3COOH measured with mist-chamber technique is systematically higher than that measured by PTR-MS (by many factors)

Possible causes – similar to those for SO2 (wall losses are most probable)

Action – Holzinger and Keene will quantify differences and continue to try to resolve nature of bias

 

4)      Low analytical resolution for Br and I in biofuels and ash

Action – Keene will contact Rich Arimoto and/or Bob Duce to inquire about the possibility of analyzing samples for Br and I via neutron activation at the University of Rhode Island.

 

5)      Mercury data are available but not yet posted on web site

 Action – Lobert will contact Friedli about posting data

 

6)      Publication status of the Logan and Yevich burning inventory   

Action – Lobert will ask Yevich about the publication status of that inventory

 

7)      The status of analyses by Mayol-Bracero and Guyon are not known

Action – Jost will ask Guyon about the status of that work, Lobert will follow up.

 

8)      Interpretation of PTR-MS data

Action – Crutzen and Holzinger will work on this during Jan and Feb

 

9)  Lackson Marufu measured emissions from domestic wood and charcoal burning during SAFARI

Action – Lobert will contact Marufu (now at UMD) about his work and possible collaboration with us

 

10)   Bob Yokelson measured emissions from agricultural burns with a FTIR during SAFARI

Action – Lobert will contact Yokelson about his work and possible collaboration with us

 

11)  AGU presentations

Action – Lobert and Keene will take lead over next month in preparing 2 papers for Fall AGU meeting. Presentations by Korontzi et al. and Hely et al. are also in preparation.

 

12)  Manuscripts

We identified and plan to prepare during Spr 02 the following manuscripts

-         Lobert et al., Emissions of methyl halides and other compounds

-         Keene et al., Emissions of soluble reactive gases and particulate-phase species

-         ? et al, Chemical mass balances in burns, possibly including an overview of the experiments

-         Jost et al., Emissions of acetone, acetonitile, and SO2

-         Holzinger, Crutzen, et al., Emissions of volatile organics

-         Landman et al., Emissions from Kruger region

-         Korontzi et al., Regional emissions for Southern Africa

Another relevant paper by Hely et al. - Analysis of fuel loads, areas burned , and C emissions near Mongu, Zambia - has already been submitted

Action – Crutzen may visit UVA in Mar/Apr to work on manuscripts

Action – Hely will give Lobert and Keene copies of her submitted manuscript

13)  Publication Schedule

Swap indicated that the submission deadline for inclusion in the first special section of SAFARI papers had been moved back from mid Feb to mid Mar 02.  Late papers may still make the section if finalized before the acceptance deadline (9 months later).  It is possible but unlikely that our manuscripts would be submitted in time for this section.  If we miss it, we will try to publish a collected set soon thereafter or, alternatively, could join a second special issue on SAFARI if the timing works out.

14)   Other SAFARI Publications and Plans

-  A book focusing on integration is planned.  This may be published with a companion book focusing on policy-related issues

-  A SAFARI workshop has been tentatively scheduled for mid October 02 at UVA.

-  Future special sections are also likely