Summary of the Fourth Workshop of Methane Working Group
(Toward an adequate quantification of CH4 emissions from land ecosystems:
Integrating field and in-situ observations, satellite data, and modeling)
March 19-20, 2009
National Center for Ecological Analysis and Synthesis
Santa Barbara, CA
During the workshop (see the Appendix A for the agenda), we reported the
progress on tasks planed in the last year’s workshop. Specifically (1) We have
successfully organized a session, entitled “Methane: Toward Accurate Estimates of
Fluxes Over Regional Scales”, organized and chaired by Christopher Butenhoff; Qianlai
Zhuang; Ed Dlugokencky, and Xiaozhen Xiong, in American Geophysical Union (AGU)
Fall Meeting. San Francisco, CA. More than 40 papers have contributed to the session.
(2) 10 papers were published in a special section, entitled “Recent Field Observations
and Modeling Studies on Methane" in the Journal of Geophysical Research Biogeosciences. In addition, we have published a synthesis article in EOS and a book
chapter on Arctic methane emissions in the United Nations Environmental Programme
Yearbook. The paper titles and authors are listed in the Appendix B. (3) We have
continually archived in situ measurement data of methane fluxes and auxiliary variables
in NCEAS Data Repository website (http://data.nceas.ucsb.edu).
During the workshop, we spent most of our time to detail our planned four
synthesis articles (See Appendix C). These synthesis papers are planned for submission
to a special issue in Biogeochemistry or Journal of Geophysical Research –
Biogeosciences. Qianlai Zhuang and John Melack are the contact persons for this special
issue/ section. We anticipate the preliminary results for these papers will be ready by
August 5th of 2009 and the results will be sufficient for putting together abstracts for the
2009 AGU Fall meeting. The complete draft of these papers will be ready by December
31, 2009. The final form of these papers will be submitted by the January 31, 2010 to
the planned special issue / section.
We also decided to organize a session in the 2009 Fall AGU annual meeting. The
session will focus on reporting these synthesis efforts and updating progresses on
methane cycling studies. Butenhoff and Zhuang will lead this activity.
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Appendix A.
Schedule for the Forth Workshop of Methane Working Group
(Toward an adequate quantification of CH4 emissions from land
ecosystems: Integrating field and in-situ observations, satellite data,
and modeling)
March 19-20, 2009
National Center for Ecological Analysis and Synthesis, Santa
Barbara, CA
March 19, 2009
8:45 a.m.
Introduction and Workshop Goals (Qianlai)
9:00 a.m.
Progress Report
(1) 2008 AGU methane session(Chris, Xiaozhen, Ed, and Qianlai)
(2) Data organization (Kim)
(3) Synthesis products (Qianlai)
1. EOS article
2. UNEP chapter
3. Special issue of JGR-B
9:30 a.m.
Writing Team Grouping
1. Controls on methane emissions across different wetland
types/ landscapes (Kim and Merritt et al.)
2. Global rice paddy emissions: A synthesis study (Aslam
and Chris et al.)
3. Methane emissions dynamics with process-based and
inverse models 2003 and 2004 in Amazon Basin (Qianlai and John
et. al.)
4. Integration of Arctic emissions of permafrost land and
lakes (Qianlai and Katey et al.)
5. Methane emissions and atmospheric concentrations in
South Asia (Xiaozhen et al.)
6. Other new initiatives (e.g., Physics today article)
10:00 a.m.
Snack and Coffee Break
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10:20 a.m.
Group Writing
12:00 -
Lunch
1:30 p.m.
Group Writing
3:00 p.m.
Snack and Coffee Break
3.30 p.m.
Group Writing
5:00 p.m.
Adjourn
6:30 p.m.
Group Dinner
March 20, 2009
8:45 a.m.
Writing Group Report
9:00 a.m.
Group Writing
10:30 a.m.
Snack and Coffee Break
10:50 a.m.
Group Writing
12:00 -
Lunch
1:30 p.m.
Group Writing
3:00 p.m.
Snack and Coffee Break
3:30 p.m.
Wrap-up
(1) Synthesis products and deliverables
(2) Data depository
(3) Final report of the project
4:30 p.m.
Adjourn
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Appendix B.
Publication associated with the Working Group
Gauci, Vincent; Blake, Stephen; Stevenson, David S.; Highwood, Eleanor J. 2008.
Halving of the northern wetland CH4 source by a large Icelandic volcanic eruption.
Journal of Geophysical Research. Vol: 113. Pages G00A11.
Gauci, Vincent; Dise, Nancy B.; Howell, Graham; Jenkins, Meaghan E. 2008.
Suppression of rice methane emission by sulfate deposition in simulated acid rain.
Journal of Geophysical Research. Vol: 113. Pages G00A07.
Khalil, M. Aslam K.; Butenhoff, Christopher. 2008. Spatial variability of methane
emissions from rice fields and implications for experimental design. Journal of
Geophysical Research. Vol: 113. Pages G00A09.
Khalil, M. Aslam K.; Shearer, M. J.; Changlin, Duan; Lixin, Ren. 2008. Production,
oxidation, and emissions of methane from rice fields in China. Journal of Geophysical
Research. Vol: 113. Pages G00A04.
Khalil, M. Aslam K.; Shearer, M. J.; Rasmussen, R. A.; Xu, Li; Liu, Jin-Luan. 2008.
Methane and nitrous oxide emissions from subtropical rice agriculture in China. Journal
of Geophysical Research. Vol: 113. Pages G00A05.
Turetsky, Merritt R.; Treat, C. C.; Waldrop, Mark P.; Waddington, J. M.; Harden, J. W.;
McGuire, A. David. 2008. Short-term response of methane fluxes and methanogen
activity to water table and soil warming manipulations in an Alaskan peatland. Journal of
Geophysical Research. Vol: 113 . Pages G00A10.
Walter, Katey; Chanton, J. P.; Chapin, F. Stuart; Schuur, Edward A.G.; ,. 2008. Methane
production and bubble emissions from arctic lakes: Isotopic implications for source
pathways and ages. Journal of Geophysical Research. Vol: 113. Pages G00A08.
White, Jeffrey R.; Shannon, Robert D.; Weltzin, Jake F.; Pastor, John; Bridgham, Scott
D. 2008. Effects of soil warming and drying on methane cycling in a northern peatland
mesocosm study. Journal of Geophysical Research. Vol: 113. Pages G00A06.
Xiong , Xiaozhen; Barnet, Chris; Maddy, Eric; Sweeney, Colm; Liu, Xingpin; Zhou,
Lihang; Goldberg, Mitch. 2008. Characterization and validation of methane products
from the Atmospheric Infrared Sounder (AIRS). Journal of Geophysical Research. Vol:
113. Pages G00A01.
Zhuang, Qianlai; Melack, John M.; Zimov, Sergei; Walter, Katey; Butenhoff,
Christopher; Khalil, M. Aslam K. 2009. Global methane emissions from wetlands, rice
paddies, and lakes. EOS, Transactions, American Geophysical Union. Vol: 90(5). Pages
37-44.
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Zhuang, Qianlai; Reeburgh, William S. 2008. Introduction to special section on synthesis
of recent terrestrial methane emission studies. Journal of Geophysical Research. Vol:
113. Pages G00A02.
Melillo, Jerry M.; Hassol, S.; Archer, D.; Callaghan, T.; Chapin, F. Stuart; Christensen,
T.; McGuire, A. David; Walter, Katey; Zhuang, Qianlai. 2008. Methane from the Arctic:
Global warming wildcard. Chapter in United Nations Environmental Programme
Yearbook. Pages 37-48.
Appendix C.
Outlines for the Proposed Special Section of Journal of Geophysical Research Biogeosciences or Biogeochemistry
Article #1: Global methane emissions from inundated regions
Zhuang, Q., J. Melillo, R. Prinn, A. D. McGuire, and members of Working Group
1. Introduction
(1) Current global estimates for different regions (e.g., Potter et al. for the U.S.)
(2) Synthesis goal of this Working Group
(3) What this series of studies have accomplished
2.
Results
(1) Surprising results
(2) Global view of methane emissions (one figure)
(3) Global quantification of emissions (one table)
3. Discussion
(1) Data products
(2) Identify gaps in these areas (each group provides that information)
Article #2: Amazonian basin-wide methane emissions
Melack, J., P. Crill, S. Houweling, Q. Zhuang and others,
1. Introduction (J. Melack)
Spatial resolution:
River-basins (100m x 100m)
Grided (1o x 1o)
Temporal resolution:
Monthly
Interannual
Inundation (10km x 10km)
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2. Method
Developing fluxes:
(1) Paint-by-numbers: Using 2 habitats data (e.g., Lehner and Doll, 2004) and
Melack’s data; Using one set of fluxes for habitats to develop a table to
include new / additional flux data
(2) MODIS or other satellite empirical approach (specific sites for developing
empirical relationships); Using two habitats data to develop the estimates
(3) Process-based modeling:
Kaplan model (Melack)
Walter model (Melack)
TEM model (Zhuang, Melack)
(4) Upland emissions
Canopy emissions (Crill)
Biomass burning (Zhuang)
Satellite data comparison
(1) Feed fluxes to TM5 and then compare to SCIAMACHY data
(Houweling, Melack)
(2) See if AIRS retrieval data can also contribute to study (Get
Houweling’s opinion)
3. Results (Melack, Crill, Houweling, Zhuang)
4. Discussion (All)
Article #3: Synthesis of Rice Field Methane Emissions
Possible contributors: Aslam Khalil, Chris Butenhoff, Xiaozhen Xiong, Sander
Houweling, Steve Frolking, Qianlai Zhang
1. Introduction
2. Processes and Models
2.1 DNDC
2.2 Yan (UNFCC) statistical
2.3 PSU – hybrid
2.4 TEM
2.5 TM5/Sciamachy Inversion
3. Description of underlying data sets
3.1. Inundation
3.2 N-Fertilizer
3.3 Organic C, green, animal, straw, roots
3.4 Crop phenology
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3.5 Rice areas
3.6 Soil temperature
3.7 Soil type
Others?
4. Calculated inventories and comparisons
4.1 DNDC
4.2 Yan
4.3 PSU
4.4 TEM
4.5 TM5/Sciamachy Inversion – Can inversion be optimized for seasonality?
5. Validation
5.1 Run bottom-up inventories through TM5 (forward modeling)
5.2 Comparison of forward runs with AIRS
5.3 Comparison of forward runs with other data sets, ground-based?
6. Observations/Discussion and Conclusions
6.1 Our thinking of the state-of-knowledge
6.2 Caveats
6.3 Data made available by project/NCEAS archive
Article #4: Towards a reconciliation of methane emissions from northern high
latitude ecosystems
(Dave, Aslam, Kim, Merritt, Katey, Sergei, Patrick, Qianlai, others?).
1. Introduction (Dave)
Provide range of estimates from different perspectives: inversions, inventories,
process models.
Identify a couple of key issues – (1) the challenge of dividing “wetlands” into
classes that optimize partitioning of the variance in fluxes; and (2) constraining
the area of wetlands that need to be considered.
2. Methods
Inversion analyses (Aslam)
Inventory analyses
Wetlands (Kim, Merritt)
Lakes (Katey, Sergei, Patrick, Kim, Qianlai)
Process-model analyses (Qianlai)
3. Results
Inversion Analyses: north of about 45 degrees (split into 45 to 60 degrees and
north of 60 degrees?). (Aslam)
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Inventory
Wetlands (Kim, Merritt): Estimates for different stratifications – only one type of
wetland, four types of wetlands (bogs, fens, fluvial, etc.) – and two different data
sets – Matthews and Global Wetland Product). Estimates could be based on
means from literature or from data base being assembled.
Lakes (Katey, Sergei, Patrick, and Kim): Estimates for different stratifications –
only one type of lake, several types of lakes (e.g., shallow/deep, fringed with
vegetation/not fringed with vegetation, permafrost/not permafrost, open/closed),
and possibly a geospatial approach (Qianlai).
Process Models (Qianlai) – Using Matthew and Fung’s global wetland data set.
4. Discussion (All)
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