IPCC Expert Meeting on HWP, Wetlands and Soil N2OWMO Geneva, 19-21 October 2010
Co-Chairs Summary•In June 2010, SBSTA 32, as part of its work programme to revise their reporting guidelines forGreenhouse Gas Emissions and removals from Annex I parties to allow the use of the 2006 IPCC
Guidelines, invited the IPCC to hold an Expert Meeting to “explore the need and ways to clarify
methodological issues related to reporting on harvested wood products, wetlands and nitrous oxide
emissions from soils” (FCCC/SBSTA/2010/L.12). In response, the IPCC Task Force on National
Greenhouse Gas Inventories held this meeting in Geneva on the 19th-21st October.

•The meeting considered the three separate topics, harvested wood products, wetlands and nitrous
oxide emissions from soil, and, in general considered that the methodological advice contained in the2006 IPCC Guidelines still reflects the latest science. A few editorial issues were noted for HWP andSoil N2O and corrigenda addressing these will be issued by the TFI.

•A meeting report will be produced that describes the discussions and conclusions in more detail andalso highlights areas where additional scientific research could contribute to future improvements inestimates of greenhouse gas fluxes.

Wetlands•The Wetland chapter (volume4, chapter 7) of the 2006 IPCC Guidelines identifies gaps which could not
be filled at the time the 2006 IPCC Guidelines were compiled. These include rewetting of peat lands
and wetland restoration (conversion of land to wetlands, and wetlands remaining wetlands), and CO2
and CH4 emissions from reservoirs (flooded land remaining flooded lands, and lands converted toflooded lands). It should be remembered that drainage and conversion of wetlands to other land uses is
included in other chapters of volume 4 (e.g. forest land, cropland and grassland): coherence between
these chapters and the wetland chapter should be maintained.

•Since the 2006 IPCC Guidelines were completed much new scientific information is now available
about various wetlands that enable emissions and removals to be estimated from wetland restoration
and rewetting especially for peat lands. The meeting recommended that the IPCC provide
additional methodological guidelines for the rewetting and restoration of peat land; emissions
from fires, ditches and waterborne carbon; and constructed wetlands for waste water disposal,
to fill gaps in the existing guidelines.

•The meeting also noted that there are now a large number of new EFs measurements and otherinformation available across climate zones for wetlands and drainage addressed in other land use
chapters. The meeting recommended that an expert meeting be held to assess these data anddevelop emission factors from this information to enable more accurate country- and regionspecific estimates to be made. The meeting also recommended that the TFI actively collect suchdata and add it to the EFDB.
•For reservoirs (flooded lands), in the 2006 Guidelines there is only a method for the estimation of CO2
from the conversion of land to flooded lands. Methods for CH4 are in appendices “for the developmentof future methodological guidance” as is a different approach for CO2 from land converted to floodedlands. The meeting discussed whether there was now sufficient new information available to produce
new and additional guidelines based on these appendices and the latest literature. The participants
discussed a range of associated issues, such as the impact of reservoirs on total emissions fromwatersheds, allocation of emissions to specific drivers and how emissions may be related to specificreservoir typologies. The meeting concluded that there should be an expert meeting to discuss all
the new science and issues surrounding the development of new guidelines for reservoirs.

Harvested Wood Products•

The meeting agreed that the methodological guidance in the 2006 IPCC Guidelines is correct, but notedthat the entire chapter needs to be considered to ensure there are no inconsistencies with other parts ofthe guidelines. The participants also noted that the guidance is complex and proposed thedevelopment of FAQ (frequently asked questions) that would guide users to the correct, full
implementation of the guidelines.

•The participants noted that to produce estimates for HWP according to the approaches currently being
discussed in the UNFCCC AWG-KP negotiations (FCCC/KP/AWG/2010/CRP.3) may require somemodification to the existing guidelines (particularly equation 12.3).

Soil N2O•

The participants agreed that the methods in the 2006 IPCC Guidelines reflect the latest scientific
literature, but the emission factors 1 were based mainly on information from temperate regions.

•They agreed that there is no N2O from the biological nitrogen fixation process itself (this was included inearlier guidelines but removed from the 2006 IPCC Guidelines).

•There has been a lot of work published on N2O emissions from soils since the 2006 IPCC Guidelines
were published and this should allow for the development of more regional or country specific emission
factors. This would allow greater stratification by climate, soil, management and leaching. The meetingproposed an expert meeting to assess recent literature and consider stratified EF1 values for
the EFDB.

•The meeting also noted that the atmospheric N2O increase is not matched by bottom-up estimates ofanthropogenic N2O emissions but the reasons for this are unclear. Increased measurements ofcurrently under represented systems (e.g. large river deltas) may help resolve this issue. This meeting
proposed a joint expert meeting with WG I to explore this gap.

TFI Co-Chairs, Geneva, 21st October 2010

1 Most importantly for EF1 but this also applies to all emission factors for soil N O emissions
2