Spatial inventory data
Data and information management
SUMMARY OF THE MAIN WORKSHOP TOPICS.
FURTHER DETAILS AND OTHER IMPORTANT TOPICS COVERED AT THE WORKSHOP, INCLUDING KEY PRODUCT GAPS CAN BE FOUND IN LATTER CHAPTERS (SEE PAGES 18, 22, 34, 37 AND 40).
There is a need for improved formal and informal mechanisms of international coordination to implement TCO. This is important both for data and information provision (e.g. definitions, observation methodologies, products) and use (climate change convention reporting, policy development).
TCO implementation requires long-term commitment to collecting specific in situ data in ways that allows their integrated use. Internationally, various mechanisms (e.g. UNFCCC, Subsidiary Body for Scientific and Technological Advice [SBSTA] and the Intergovernmental Panel on Climate Change [IPCC]) have been established to develop agreed-upon definitions and observation methods related to the carbon cycle. However, the actual data collection, assembly and use remains uncoordinated, thereby preventing or severely hindering the creation of accurate, harmonized long-term observational products.
There is a need for a well structured framework whereby national, regional, and international bodies can reach agreement and ensure that commitments are fulfilled. The framework must include formal international coordination mechanisms through appropriate inter-governmental bodies such as the United Nations (UN), as well as less formal international bodies that are effectively linked to national efforts. A useful informal mechanism is the involvement of science and policy communities that participate in both national and international initiatives.
The TCO implementation plan should build on previous terrestrial carbon cycle developments.
1. Scientists and policy specialists involved in UNFCCC and other environmental conventions should participate in the preparation and review of the TCO implementation plan, and should consider current as well as future needs.
2. Appropriate bodies should be identified to carry out the international coordination of each activity. Contact points of individual bodies should be engaged to assist in the implementation process. Where absent an international coordination mechanism should be created, primarily within the framework of existing international organizations.
3. At the national level, TCO should provide guidance on observation methods and pursue improved access to national data sets. This may be accomplished by preparing guidelines for national and regional terrestrial observing systems; by developing a library of 'best practice' methods, and by incorporating a national perspective in the TCO DISS (Chapter 6).
Current atmospheric composition measurements and transport models are inadequate to reliably constrain terrestrial flux estimates through bottom-up procedures and to establish quantitative links between the climate system and its perturbation by anthropogenic and/or natural terrestrial processes.
The large regional uncertainties and the coarse spatial resolution used in atmospheric composition data does not allow changes in atmospheric greenhouse gas (GHG) to be allocated to specific geographical regions and/or terrestrial processes. These uncertainties are due to inadequate atmospheric GHG composition measurements and deficiencies in current atmospheric transport models.
Immediate priorities include: improved atmospheric composition measurements over continental regions; the need to meet (long-established) requirements for merging data from different networks, and better exploitation of chemical signatures in the atmosphere in a synergistic approach with terrestrial carbon cycle processes.
1. Implement vertical sounding and high frequency (or continuous) systematic observations of atmospheric composition over major biomes which will allow to link surface processes directly to atmospheric composition changes. Improve atmospheric transport models that resolve regional influences on surface flux and composition measurements.
2. Adhere more closely to existing World Meteorological Organization (WMO) calibration guidelines. Improve high-precision measurement techniques to diagnose systematic errors across the networks. Create an adequate framework to monitor differences in a transparent and verifiable manner.
3. Measure a larger group of chemical species that are involved with the main GHGs in important processes, e.g. carbon and oxygen isotopes in CO2, O2/N2 ratio, CO, H2, CH4, volatile organic carbon (VOC).
4. Plan an in situ observation network which will use more fully atmospheric measurements from satellite platforms.
5. Other issues (refer to Table 4).
The adequacy of direct in situ flux measurements.
Eddy correlation flux measurements are presently the primary independent method for validating carbon fluxes estimated by models, which in turn are driven by gridded input data. The current network (FLUXNET) assembled from several regional and/or national networks has two major deficiencies: an incomplete sampling of the multi-dimensional environment (see Terrestrial measurements on page 18), and a dependence on research funding that renders uncertain the continuity of the observations needed for TCO.
Improve and increase the consistency of the eco-climatic coverage of FLUXNET.
1. Develop a biome-based sampling scheme based on considerations of flux magnitude per unit area, the current understanding of the biome processes (including spatial and temporal variability), and the needs of model output validation procedures.
2. Encourage new flux sites to be established in areas that are under sampled.
TCO should work with international agencies such as FAO, United Nations Environment Programme (UNEP), UNFCCC, Global Environment Facility (GEF), and the International Group of Funding Agencies for Global Change Research (IGFA), as well as with national agencies in promoting the need for long-term funding to achieve sustained observations at key sites.
Non-flux sites and measurement gaps
The collection of critical carbon cycle data from existing or new point sites is currently not comprehensively captured. There needs to be an effective use of measurements from established ecological networks, which in most cases do not measure carbon fluxes.
TCO requires in situ measurements of carbon cycle components to characterize carbon budgets and to test the performance of process models. There are existing ecological sites that measure carbon dynamics (i.e. productivity and respiration) or collect measurements of single carbon budget components (e.g. above-ground biomass). However, these measurements are often incomplete for TCO applications as they are acquired for other purposes. In addition, carbon cycle processes are not evenly represented in the point data coverage. In particular, carbon uptake processes and their drivers are better represented than carbon release processes.
There is a need to review existing observations (Appendix 3), identify possible improvements and bring together key data available from the major networks. This also includes associating biome, vegetation, climate, soil and other information with each site, and placing the data within an environmental space framework to help identify data gaps. For this to be achieved networks and sites should be contacted for data and documentation which will be harmonized and shared. The environmental space framework can also be used to identify gaps in separate data collections and to propose ways to supplement existing observations. Current priorities appear to be soil respiration, litter quality and decomposition data.
1. Develop inventories of sites within major networks, place the sites within a multi-dimensional environmental framework. Acquire or establish links to key data sets, and consider ways of synthesising the data for TCO needs. Methodological options are data assimilation (to ensure a complete and consistent data stream) and data fusion (combining two or more data streams).
2. Reduce uncertainty in the estimates of carbon pools and fluxes by filling observation gaps.
3. Design a data template for soil respiration data and then create a data repository for the large volumes of respiration data presently being collected.
4. Identify existing temperate and tropical data set holders for soil litter and encourage them to contribute these to form the nucleus of a global data set.
In situ data for satellite products
In situ data are also an important input in the generation of data products from satellite measurements.
Most in situ data are collected without regard to how they will be scaled with satellite data to represent carbon-related variables over large spatial scales. Given the costs and difficulties in acquiring quality in situ data, there is a strong need for concerted action.
An important initial need are guidelines for harmonizing existing data and collecting new data. These would help to support the goal of linking globally-representative in situ data with globally-comprehensive satellite image data. The key variables that can be derived from satellite data at the global scale include land cover, land-cover change (e.g. disturbance, succession), leaf area index (LAI), and biomass amount and change (Table 1 and Specific data needs, page 16). Some in situ data are quite detailed and useful at the local level, whereas other data are more generally applicable.
Similarly, satellite data span the scale of 'detailed and locally applicable' (e.g. IKONOS) to 'generalized and globally useful' (e.g. Moderate resolution imaging spectroradiometer, MODIS). This variance sets up an opportunity to employ nested approaches to linking the two data types, and for scaling from detailed local level (e.g. BigFoot) to regional (e.g. SAFARI) and global (e.g. MODIS land group, MODLAND) synthesis. In situ data are needed at the initial stages for the validation of algorithms transforming satellite data into biophysical products, and later to ensure that the products remain accurate and reliable. There is therefore a need for a union between in situ data collection and satellite data processing streams. TCO must work closely with the Global Observation of Forest and Land Cover Dynamics (GOFC-GOLD) and the Global Carbon Project (GCP) to coordinate timely access to in situ data.
1. Adopt or develop guidelines in collaboration with CEOS working groups, for linking globally- representative in situ data with globally-comprehensive satellite image data.
2. Pursue opportunities for new data inputs from new sensors (e.g. Vegetation Canopy Lidar [VCL] mission for biomass).
3. Develop mechanisms to ensure that the necessary in situ data are available to support an ongoing generation of quality satellite products.
4. Encourage and support efforts to improve the calibration of satellite measurements and links to international standards.
More effective use of data from national resource inventories and from related spatial data sets.
Global maps of carbon fluxes, Net Primary Productivity (NPP) and Net Ecosystem Productivity (NEP) have been produced based on Earth Observation (EO) data. Models have mainly produced the critical information on carbon stocks needed for these flux calculations. Confidence in these EO-based products is limited by the lack of independent data to check model estimates of stocks. It is now possible to develop an integrated global data-model system that allows the analyses of different effects of fossil fuel emissions, biology, and land management on spatial patterns of atmospheric CO2. However, this also requires a range of spatial data sets.
There is a need for gridded carbon stock and crop yield data at spatial resolutions coarser than 1 km2. National forest inventories can be used to obtain gridded above-ground biomass in forest ecosystems. Soil information databases from many countries can be gathered to obtain spatial soil carbon information. Although global coverage of inventory data sets is highly desirable, regional or large national data products will also be useful to help constrain the model results and to improve user confidence in the model outputs. There is also a need to develop spatially and temporally resolved data sets for input, verification, and validation of estimates of terrestrial carbon exchanges and associated relevant terrestrial processes (Table 1 and Specific data needs, page 16). Depending on the use, these data sets should be regional or global in coverage.
1. Request organizations with relevant forest inventories to prepare rasterized biomass distribution data products (grid cell size ~100 km2). Local expertise is essential for archiving quality products as conversion factors between biomass components are region- and species- specific. TCO should ensure that consistent methodologies are developed for the conversion process so that the country results are comparable regionally and preferably globally. While forests are the most important ecosystem, other cover types such as shrub land should also be included if possible.
2. Obtain gridded annual crop yield data and convert this into biomass data. Support data with a rigorous review and document the conversion factors used to estimate the biomass volume from yield data.
3. Assemble available digital soil information databases and possible soil polygon maps to extract or derive total soil carbon information and rasterize it (grid ~100 km2). All ecosystems, including forest, crop, grass, tundra, shrub, etc. should be included. TCO should collaborate with agencies and projects working to improve soil carbon information, e.g. FAO, IGBP, Soils and Terrain Database (SOTER).
4. Contact existing data collection agencies and institutions responsible for critical global or regional data sets. Develop a framework for data access and manipulation, and establish collaborative efforts for data analysis, carbon exchange calculations, inversion analyses, and model verification.
5. Define and implement an appropriate coordination/execution mechanism, such as a TCO data management facility (Chapter 6). The facility should have strong linkages to collaborating agencies and programmes, and suitable terms of reference.
Data and information systems and services for TCO.
The success of TCO will depend on an efficient mechanism that facilitates access to, and use of, the diverse data types needed to quantify the terrestrial carbon cycle. IGOS-P theme implementation guidelines also require such a mechanism.
Effective communication (by users, at different levels of complexity, and for different services) with the information systems established by TCO partners will be a crucial factor in TCO success. This is evident from the experience of numerous collaborative projects, and is also reflected in IGOS-P guidelines for the implementation of observation themes. One way to realize these objectives is to establish a Data and Information Systems and Services (DISS), which would provide a range of services, including:
As part of the preparation of the TCO implementation plan, the TCO DISS concept should be developed and discussed with TCO partners.