Concerted Actions for a Global Biomass Monitoring Initiative
Schmullius, Christiane1; Seifert, Frank Martin2; Reichstein, Markus3
1Dept. for Earth Observation, University Jena, GERMANY; 2ESA-ESRIN, ITALY; 3MPI-Biogeochemistry, GERMANY

Biomass is recognized by the United Nations Framework Convention on Climate Change (UNFCCC) as an Essential Climate Variable (ECV) and several requirements were defined to improve the reliability of biomass estimates and their utility for a better monitoring and understanding of climate change. Overcoming observation and measurement inconsistencies and uncertainties are critical to better understand the role of forests in the global carbon exchange. Therefore, a global assessment of biomass and related dynamics are essential inputs to climate change forecasting models and mitigation and adaptation strategies.

Vegetation biomass is a crucial ecological variable for understanding the status, condition, and potential future changes to the climate system. Vegetation biomass is a large global store of carbon. Changes in the amount of vegetation biomass have been identified as having an effect on the C02 content of the global atmosphere. Forest utilization and management activities, through harvesting, deforestation (conversion to non-forest land use), or reforestation impact and add complexity to the flow of carbon between forests and the atmosphere. Two other emerging issues contribute to the increasing importance of the biomass role as an essential climate variable: i) the growing use of biomass for energy production, so the increasing percentage of global greenhouse gases (GHGs) emitted from biomass consumption, and ii) the increasing concern on the possibility to significantly reduce global GHGs emissions by avoiding biomass losses from deforestation and forest degradation.

In 2001, the Japan Aerospace Exploration Agency (JAXA) launched their Kyoto & Carbon Initiative [] to demonstrate the feasibility of their Earth observation sensors to climate related surface parameters. The development of products relating to land cover mapping, forest change mapping and forest biomass and structure has resulted in pre-operational classification techniques and consistency evaluations. Thanks to JAXAs systematic observation strategy, the following acquisition concepts were fulfilled: spatial and temporal consistency over continental scales at fine resolution, adequate revisit frequency, accurate timing with consistent sensor configuration, and thus long-term continuity.

In 2002, the North American Carbon Programme (NACP []) published its Science Plan followed by an Implementation Strategy in 2005 in which tracking forest above-ground biomass gained high attention and stimulated a wealth of wall-to-wall mapping and validation projects, specifically developing synergistic use of LiDAR-data.

In 2008, GOFC-GOLD (Global Observation of Forest Cover and Land Dynamics) initiated a Biomass Working Group [] to

  • establish an international coordination and communication platform to enhance biomass monitoring using a combination of satellite and in-situ observations,
  • bridge needs and requirements from the international user community with remote sensing observation progress developed in the research domain by specifying suitable products towards operational implementation,
  • support and integrate evolving international projects and programmes to improve the global monitoring of biomass as Essential Climate Variable,
  • harmonize different methodologies for data collection, analysis, and validation,
  • foster cooperation and exchange of data and information among different communities and agencies involved in biomass and carbon assessments,
  • integrate activities with a number of other relevant ECV observation products, in particular of land cover and fire. This Working Group has contributed to the GTOS (Global Terrestrial Observing System) Report 67 on Biomass, published in 2009 [].

    In May 2009, after a GEO Forest Symposium in November 2008, a first GEOSS Forest Observations for Carbon Tracking Workshop was held and formulized in the Forest Carbon Tracking Task (GEO FCT) as part of the GEO 2009-2011 workplan (task CL-09-03b). This task has been established to support countries wanting to establish national forest-change, carbon estimation and reporting systems and to facilitate access to long-term satellite, airborne and in situ data, to provide the associated analysis and prediction tools, and to create the appropriate framework and technical standards for a global network of national forest carbon tracking systems []. This is now brought forward towards a more operational level with the Global Forest Observation Initiative (GFOI) [].

    In time to prepare the upcoming Sentinel-data exploitation, the first ESA GlobBiomass User Consultation Meeting in October 2012 in Jena, Germany, can be regarded as the starting point for a potential future GlobBiomass project funded by ESA and concerted with other space agencies to make best use of current space asset []. Its major objectives were to survey user requirements for global and regional biomass information and to explore the feasibility of meeting these requirements with available satellite data and techniques. To set a list of priority requirements to be addressed by a future project, a questionnaire had been circulated amongst participants and interested parties. The needs can be summarized as follows:

  • multi-temporal above-ground biomass (AGB) maps (ideally with annual repetition),
  • fine spatial resolution (≤100m for national applications) and spatial continuity,
  • mainly requests for a global product, tropics are request second often,
  • transparent and standardized methods which have to be fully documented,
  • easy to use/interpret and easy/free access,
  • clear and transparent reporting of accuracy/ uncertainty,
  • synergy of sensors and installation/implementation of long-term field sites,
  • some requests for fuel sizes classes (branches, twigs, leaves) and a belowground biomass product.

    This paper will discuss the detailed user requirements from scientists, NGOs and industry from the GlobBiomass questionnaire in the context of existing procedures and products, the availability and quality of (partially unused) data archives and an outlook to the new satellite generation, specifically LDCM and the Sentinel-family.