Report from the International Permafrost Association: carbon pools in permafrost regions

The IPA Carbon Pools in Permafrost Regions (CAPP) Project started in 2005, with endorsement of the Earth System Science Partnership (EESP) Global Carbon Project and the World Climate Research Programme (WCRP) Climate and Cryosphere Project. CAPP is also a project of the IPY. The project was launched because there is considerable concern and increased awareness both within the international scientific community and the general public about the effects of global warming on the very large soil organic-matter pool in permafrost regions (Figure 1). A new estimate (Schuur et al., 2008; Tarnocai et al., 2009) indicates that the total below-ground carbon pool in permafrost regions (ca. 1672 PgC) is more than double the present atmospheric pool (ca. 730 PgC) and more than three times larger than the total global forest biomass (ca. 450 PgC). Permafrost degradation has already been observed in parts of the northern circumpolar region and a significant portion of permafrost is expected to thaw this century (ACIA, 2004). This could result in the release of greenhouse gases (both carbon dioxide and the much more potent methane) from soil organicmatter decomposition. This positive feedback within the Earth System has not yet been considered in climate model projections of future global warming. A unique aspect of permafrost degradation is that gradual thawing of the ground with depth over time will be accompanied by more dramatic events, such as ground subsidence due to melting of buried ice bodies and lateral erosion along the edges of thaw lakes and arctic coastlines (Figure 2), further accelerating the release of greenhouse gases. CAPP is not a funding programme. Its aim is to develop a network of established and young scientists carrying out research on a wide range of topics related to carbon in permafrost in order to discuss the most recent findings and insights. A 1 CAPP-related workshop took place in Stockholm from 24–26 November 2005; new results will be discussed at the 2 CAPP workshop to be held in Stockholm from 3–5 June 2009. CAPP will participate in the IPA contribution to the IPY Oslo Science Conference and organise a session at the 3 European Conference on Permafrost in Svalbard, both in June 2010. The overall aims of the IPA CAPP Project are to assess below-ground organic-matter quantity and quality along ecoclimatic and edaphic gradients in high-latitude and high-altitude regions characterised by the presence of permafrost. The longer term plan of IPA CAPP is to contribute and initiate new research activities at up to 10 to 12 high-latitude transects in the northern hemisphere representing the range of ecoclimatic and permafrost regions, complemented by transects in subantarctic and high alpine environments. Intensive study sites along transects will permit investigation of below-ground carbon allocation in the landscape, comparing quantity and quality between different permafrost settings. Within the more limited time frame of IPY 2007–09, an important objective for CAPP has been to contribute to the Northern Circumpolar Soil Carbon Database (NCSCD), maintained by Charles Tarnocai (Ottawa). In cooperation with the IPA Cryosol Working Group and the Global Carbon Project, a new update has now been completed (Tarnocai et al., 2009). An Atlas of Northern Circumpolar Soil was also recently produced (European Commission, 2009). CAPP-related research is underway in Alaska, Canada, Scandinavia and Russia. Here, we present some recent results, including an update of the soil carbon database, assessments of different permafrost carbon pools from across the Circumpolar North and the role of thawing permafrost PERMAFROST AND PERIGLACIAL PROCESSES Permafrost and Periglac. Process. 20: 229–234 (2009) Published online 19 May 2009 in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/ppp.648