Empa – Swiss Federal Laboratories for Materials Testing ... · International Foundation HFSJG Activity Report 2008 45 Name of research institute or organization: Empa – Swiss

International Foundation HFSJG Activity Report 2008

45

Name of research institute or organization:

Empa – Swiss Federal Laboratories for Materials Testing and Research Title of project: Halogenated greenhouse gases at Jungfraujoch --- New substances on the horizon Project leader and team: Martin K. Vollmer, Stefan Reimann (project leader), Brigitte Buchmann, Matthias Hill, Christoph Hueglin Project description: Halogenated ozone-depleting substances (ODS) and greenhouse gases (GHG) have been monitored at Jungfraujoch since 2000. The measurements aim at several purposes. Most importantly, these measurements help to identify regional pollution of these substances and build the basis for a quantitative estimate of regional emissions using atmospheric transport models to identify the origin of the polluted air masses. The measurements also help to identify ‘new’ substances. Due to the restriction on the uses of ODS within the Montreal Protocol (e.g. the chlorofluorocarbons, CFCs), new replacement chemicals are being produced by the industry. Some of these substances are greenhouse gases, particularly the ‘3rd generation’ compounds, the hydrofluorocarbons (HFCs).

In February 2008, the ‘Adsorption-Desorption System’ (ADS) gas chromatograph mass spectrometer (GCMS) at Jungfraujoch was replaced by a new system with improved sample preparation capabilities. The new GCMS instrument with a sample preparation unit termed ‘the Medusa’, was designed by the Scripps Institution of Oceanography (B. R. Miller et al., Anal. Chem, 2008) and allows for faster and more precise measurements compared to the ADS-GCMS, which was decomissioned after ~6 month of overlapping measurements with the Medusa system.

Table 1: List of compounds currently measured by the Medusa-GCMS at Jungfraujoch. The compounds are separated into columns according to their treatments within the Montreal and Kyoto Protocols.* HFC-245fa is currently not part of the Kyoto Protocol but its isomer HFC-245ca.

Montreal Protocol Kyoto Protocol Not regulated

CFC-11 HCFC-22 HFC-23 CF4 CH3Cl C2H2 CFC-12 HCFC-141b HFC-32 PFC-116 CH3I C2H4 CFC-13 HCFC-142b HFC-134a PFC-218 CHCl3 C2H6 CFC-113 HCFC-124 HFC-152a SF6 CHBr3 C6H6 CFC-114 CH3Br HFC-125 CHClCCl2 C7H8 CFC-115 CH3CCl3 HFC-143a CCl2CCl2 H-1211 CCl4 HFC-365mfc SO2F2 H-1301 HFC-245fa * H-2402 HFC-227ea HFC-236fa


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240

245

250

255

260

CFC

−11

APR MAY JUN JUL AUG SEP OCT NOV

20

25

30

HC

FC−

141b

0.4

0.5

0.6

PFC

−21

8

0

1

2

HFC

−36

5mfc

0

100

200

benz

ene

1

2

3

SO2F 2

500

600

CO

S

Figure 1: Tropospheric mixing ratios for a selection of compounds measured by the GCMS-Medusa at Jungfraujoch in 2008. The data in black denote pollution events and those in red are depletion (sub-background) events. Data in blue and green are from air masses that are free of regional pollution (background) and were derived using a statistical filter (rfbaseline, R-project). For COS, this filter was not applied. A strong depletion (grey) and a strong pollution (dark green) event is highlighted.

In Figure 1 we show a 6-month record for a selection of compounds measured by the Medusas system. The data are colored according to their classification into background, pollution and depletion air. All major compounds treated under the Montreal Protocol are now measured precisely at Jungfraujoch. This allows to detect pollution events of small magnitudes. For the chlorofluorocarbons (CFCs), our


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measurements show that despite the complete ban from usage of these substances in the Non-Article-5 countries (mainly developed countries) under the Montreal Protocol more than 10 years ago (1996), several of these substances are still being emitted in quantities which are being detected at Jungfraujoch after transport from the sources to the site.

In particular, the long-lived and abundant ODS CFC-11, CFC-12, and CFC-113 show some European pollution events. This is exemplified with the pollution event in early June 2008 showing enhanced CFC-11 mixing ratios. These pollution events for CFC-11 and CFC-12 are likely due to emissions from banked substances (reservoir ODS installed in equipment such as foams),

The second-generation Montreal Protocol substances are the HCFC, which are now generally banned in Europe and globally regulated in a phase-out plan over the next decades. As a results, HCFC-141b pollution events have stabilized in magnitude and frequency over the last years. In contrast to the CFCs, the background mixing ratios of the HCFCs are increasing mainly due to the increased use in Art-5-countries (mainly the Asian regions).

In addition to pollution events, there are also observations of ‘depleted’ mixing ratios at Jungfraujoch. These are mainly observed for substances with lifetimes of typically <10 yrs or for rapidly growing substances. These depletion events denote air mass arrivals from regions of lesser abundance, i.e. higher altitude (stratosphere) or lower latitudes (south, and southern hemisphere, Atlantic Ocean). A major depletion event was observed in April 2008 (Fig. 1).

Third generation foaming agents and refrigerants (HFCs -134a, -152a, -125, -365mfc, -245fa, -236fa) are globally emitted in large quantities and have lead to rapid increases in the background mixing ratios over the last decade. Some are characterized by large and frequent pollution events arriving at Jungfraujoch (e.g. HFC-365mfc, Fig. 1).

The Medusa GCMS system also allows for measurements of perfluorated carbon (PFCs) and sulfur species, some of which have extremely long atmospheric lifetimes, and which are part ot the GHG baskets under the Kyoto Protocol. While all PFCs and SF6 show increasing background concentrations, pollution events are rare compared to other Kyoto Protocol compounds. For example, the PFC-218 (C3F8) Jungfraujoch record (Fig. 1) shows only one clear (and relatively large) pollution event in June 2008.

Several of the predominantly anthropogenic volatile organic compounds (VOCs) are also monitored at Jungfraujoch. These generally have short-lived atmospheric lifetimes (order of months or less) and are characterized by large and frequent pollution events but also by large seasonal cycles in background air, which are mainly controlled by the seasonality of the sink meachanism of these compounds, the destruction by the hydroxyl radical (OH). Among the measured substances are benzene (Fig. 1), toluene, and other short-chained hydrocarbons such as C3 – C6 substances.

Atmospheric trace gas research has made progress in recent years by early detection of ‘new’ compounds. While several of the HFCs have only been mass-produced and emitted in recent years, there are other compounds to which attention should be drawn. These are e.g. the climate-active substances nitrogen trifluoride NF3, and some halogenated compounds (e.g. C2ClF3, Laube et al., 2008), which are currently


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under investigation for continuous measurements on the Medusa. Here we show the record of disulphuryl fluoride (SO2F2) at Jungfraujoch. This substance serves as a fumigant (structural, agricultural) replacement for the regulated potent ODS methyl bromide (CH3Br). This substance is currently not permitted for usage in Switzerland and the air trajectories for the measured pollution indeed point to sources outside Switzerland.

While the focus of the project is on anthropogenic compounds, some attention is also drawn to substances with large biological components. For example, carbonyl sulfide (COS) is a substance whose atmospheric abundance is largely characterized by its major sink, uptake by plants. COS is a tracer for plant productivity and is a promising helpful piece in the carbon cycle puzzle, because it lacks a plant source (which for CO2 is plant respiration). Measurements of COS at Jungfraujoch show occasional large negative excursions pointing to regional (plant) sinks. The major pollution event in June 2008 mentioned earlier is characterized by a large drawdown in COS, suggesting long ground-based residence times of the air masses before transport to Jungfraujoch.

Most compounds mentioned here are also observed at other ground-based stations distributed around the world within the international networks NOAA-GMD, AGAGE, SOGE, and affiliated stations in Asia. In addition to background measurements, recent studies have also focused on characterization and quantification of pollution around the globe. It is hoped that the budgets of climate-relevant trace gases can be better characterized through the advancements in measurement and modeling techniques thereby leading to improved understanding of the distributions and trends of the predominantly anthropogenic sources of these substances.

Key words: Ozone-depleting compounds, greenhouse gases, Montreal Protocol, Kyoto Protocol Collaborating partners/networks: Bundesamt für Umwelt (BAFU) / Federal Office for the Environment (FOEN) Global Atmosphere Watch (GAW) SOGE (System for Observations of Halogenated Greenhouse Gases in Europe) AGAGE (Advanced Global Atmospheric Gases Experiment) This research was financially supported by FOEN Scientific publications and public outreach 2008: Refereed journal articles and their internet access Balzani-Lööv J. M., S. Henne, G. Legreid, J. Staehelin, S. Reimann, A. S. H. Prevot, M. Steinbacher, M. K. Vollmer, 2008. Estimation of background concentrations of trace gases at the Swiss Alpine site Jungfraujoch (3580 m asl). Journal of Geophysical Research, 113, D22305, doi: 10.102972007JD009751. http://www.agu.org/pubs/crossref/2008/2007JD009751.shtml

Folini, D., S. Ubl, P. Kaufmann, Lagrangian particle dispersion modeling for the high Alpine site Jungfraujoch. Journal of Geophysical Research 2008, 113, D18111, doi: 10.1029/2007JD009558. http://www.agu.org/pubs/crossref/2008/2007JD009558.shtml


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Laube, J. C., A. Engel, 2008. First atmospheric observations of three chlorofluorocarbons, Atmospheric Chemistry and Physics, 8, 5143-5149. http://www.atmos-chem-phys.net/8/5143/2008/acp-8-5143-2008.pdf

Lanz V. A., C. Hueglin, M. K. Vollmer, M. Steinbacher, S. Henne, J. Staehelin, B. Buchmann, S. Reimann, 2008. Statistical analysis of non-methane hydrocarbon variability at a European background location (Jungfraujoch, Switzerland). Atmospheric Chemistry and Physics Discussions, 8, 19527-19559. http://www.atmos-chem-phys-discuss.net/8/19527/2008/acpd-8-19527-2008.html

Legreid G., D. Folini, J. Staehelin, J. Balzani Lööv, M. Steinbacher, S. Reimann, 2008. Measurements of organic trace gases including OVOCs at the high alpine site Jungfraujoch (Switzerland): Seasonal variation and source allocations. Journal of Geophysical Research, 113, D05307, doi: 10.1029/2007JD008653. http://www.agu.org/pubs/crossref/2008/2007JD008653.shtml

Reimann S., M. K. Vollmer, D. Folini, M. Steinbacher, M. Hill, B. Buchmann, R. Zander, E. Mahieu, 2008. Observations of Anthropogenic Halocarbons at the High-Alpine site of Jungfraujoch. Science of the Total Environment, 391, 224-231. http://dx.doi.org/10.1016/j.scitotenv.2007.10.022

Steinbacher M., M. K. Vollmer, B. Buchmann, S. Reimann, 2008. An evaluation of the current radiative forcing benefit of the Montreal Protocol at the high-Alpine site Jungfraujoch. Science of the Total Environment, 391, 217-223. http://dx.doi.org/10.1016/j.scitotenv.2007.10.003

Conference papers Gheusi, F., S. Henne, D. Brunner, J. Staehelin, Small-scale transport of ozone and CO to the high-Alpine observatory Jungfraujoch (3580 m asl): a fine-scale model strategy and first results, IGAC 10th International Conference, Annecy, France, September 07-12, 2008.

Lanz, V., A. S. H. Prevot, C. Hüglin, Transport and ageing of organic aerosols, EGU General Assembly 2008, Vienna, Austria, April 13-18, 2008.

Steinbacher, M., M. K. Vollmer, B. Buchmann, S. Reimann, An evaluation of the current radiative forcing benefit of the Montreal Protocol at the high-Alpine site Jungfraujoch, Swiss Global Change Day, Bern, Switzerland, April 01, 2008.

Steinbacher, M., M. K. Vollmer, S. Henne, D. Brunner, B. Buchmann, S. Reimann, In-situ measurements of non-CO2 greenhouse gases at Jungfraujoch, Switzerland, IGAC 10th International Conference, Annecy, France, September 07-12, 2008.

Steinbacher, M., M. K. Vollmer, S. W. Bond, B. Buchmann, S. Reimann, H2 observations in the atmosphere: an integration from the exhaust pipe to a remote site, IGAC 10th International Conference, Annecy, France, September 07-12, 2008.

Werner, A., A. Engel, A. Jordan, I. Levin, E. Nisbet, K. Rozanski, T. Röckmann, M. Schultz, M. Steinbacher, F. Stordal, EUROHYDROS – a European Network for Atmospheric Hydrogen Observations and Studies, EGU General Assembly 2008, Vienna, Austria, April 13-18, 2008.

Vollmer, M. K., S. Reimann, S. Henne, D. Brunner, M. Steinbacher, B. Buchmann, Using observations of atmospheric greenhouse gases at Jungfraujoch (Switzerland) to validate regional bottom-up emissions, AGU General Assembly 2008, San Francisco, Dec 15 – 19.


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Theses Lanz, V., Atmospheric transformation and source attribution of reactive organic compounds, PhD Thesis Nr. 18019, ETH Zurich.

Data books and reports BAFU, NABEL Luftbelastung 2007. Umwelt Zustand Nr. 0823, pp. 139. Bundesamt für Umwelt, Bern, 2008.

GCOS, Lokal messen …, Swiss GCOS Office, pp. 32, Bundesamt für Meteorologie und Klimatologie MeteoSchweiz. Address: Empa Laboratory for Air Pollution/Environmental Technology Ueberlandstrasse 129 CH-8600 Dübendorf Contacts: Martin K. Vollmer Tel.: +41 44 823 4242 Fax: +41 44 821 6244 e-mail: [email protected]

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Empa – Swiss Federal Laboratories for Materials Testing ... · International Foundation HFSJG Activity Report 2008 45 Name of research institute or organization: Empa – Swiss