National GHG Inventories Research Articles

Reconciling global-model estimates and country reporting of anthropogenic forest CO2 sinks

Achieving the long-term temperature goal of the Paris Agreement requires forest-based mitigation. Collective progress towards this goal will be assessed by the Paris Agreement’s Global stocktake. At present, there is a discrepancy of about 4 GtCO2 yr−1 in global anthropogenic net land-use emissions between global models (reflected in IPCC assessment reports) and aggregated national GHG inventories (under the UNFCCC). We show that a substantial part of this discrepancy (about 3.2 GtCO2 yr−1) can be explained by conceptual differences in anthropogenic forest sink estimation, related to the representation of environmental change impacts and the areas considered as managed. For a more credible tracking of collective progress under the Global stocktake, these conceptual differences between models and inventories need to be reconciled. We implement a new method of disaggregation of global land model results that allows greater comparability with GHG inventories. This provides a deeper understanding of model–inventory differences, allowing more transparent analysis of forest-based mitigation and facilitating a more accurate Global stocktake. The model–inventory discrepancy in net land-use carbon emissions mainly results from conceptual differences in estimating anthropogenic forest sinks. A revised disaggregation of global land model results allows greater comparability with inventories.

A comparison of methane and nitrous oxide emissions from inland mixed-fish and crab aquaculture ponds

Inland aquaculture ponds in China collectively cover 2.57 million ha, so emissions of the greenhouse gases methane (CH4) and nitrous oxide (N2O) from these ponds may constitute a significant contribution to global warming. During 2016 and 2017, CH4 and N2O fluxes and a range of pond-water and sediment properties were measured in replicated (n = 4) “mixed-fish” and “crab” aquaculture ponds in southeast China. Annual CH4 and N2O emissions were 64.4 kg C ha−1 and 2.99 kg N ha−1, respectively, from the “mixed-fish” ponds, and 51.6 kg C ha−1 and 3.32 kg N ha−1, respectively, from the “crab” ponds. Emission differences between pond types were significant (p < 0.05) for both gases. CH4 fluxes from the “crab” ponds were significantly increased by the presence of aquatic vegetation, but N2O fluxes were not affected. Emissions of N2O were estimated to be 0.54% and 0.71% of the total nitrogen input (in the feed) for the “mixed-fish” and “crab” ponds, respectively. The net economic benefit-scaled sustained-flux global warming potential (NEB-scaled SGWP) of the “crab” ponds was 61.6% higher (p < 0.05) than that of the “mixed-fish” pond. Our CH4 and N2O emissions results suggest that aquaculture ponds can be important contributors to regional and national GHG inventories, with aquaculture type an important factor in total GHG impact. Further CH4 and N2O flux research is needed at aquaculture ponds across China to better establish the range of potential GHG impacts, and to confirm the importance of the influencing factors identified in this study.

Improved climate change understanding and projections for coal businesses create urgent need to initiate stronger measures toward coalbed methane in India

ABSTRACTIn this opinion paper, we contend that in light of recent findings and the expected future of Indian coal business, fugitive methane emissions from coal mining and handling activities may come to occupy a larger share of the national GHG inventory, and therefore methane mitigation through various approaches of coalbed methane (CBM) extraction should occupy significantly more importance in mitigating climate change. The factors in play here are the increasing global warming potential (GWP) of methane from the second to the fifth assessment reports of the IPCC, calls by researchers to shift to 20-year time frames for GWP, increasing coal production by India and the availability of coal mine methane (CMM) technology for simultaneous coal and gas production.

국가 온실가스 감축목표 달성을 위한 지자체 온실가스 배출특성 연구

In this study, GHG inventory on 17 local government between 2005 and 2014 is build up using ‘GHG emission estimation guideline (2016. 2) for local government’ developed and distributed by KECO. This covers all the sectors should be included in national GHG inventory, which are energy, industrial process, agriculture, AFOLU, and waste. In addition, six GHGs, carbon dioxide, metane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, sulphur hexafluoride declared in Kyoto protocol are estimated to reflect utmost precision. Indirect esissions, such as electricity, heat and waste generation are separately estimated as well as direct emissions to help local government to establish substantial and implementable reduction measures of GHGs.

National greenhouse gas inventory capacity: An assessment of Asian developing countries

The transparency framework of the Paris Agreement (PA) will be elaborated from the existing arrangements under the UN Framework Convention on Climate Change (UNFCCC). Yet, the capacities of developing countries to regularly report national GHG inventories vary, and their needs for capacity building are closely linked with efforts and achievements of previous inventory preparation. The purpose of this study was to analyze the status and changes in the capacity of 37 developing countries in Asia by using a matrix of capacity-indicators. Indicators were composed for four assessment categories: (1) international engagement of a country in the GHG inventory-related process; (2) institutional capacity to produce a GHG inventory; (3) existing technical capacity available to develop a GHG inventory; and (4) actual technical capacity applied to produce a GHG inventory. The paper also analyzed the scale of international support and variations in meeting with capacity building needs. Eleven countries were identified as having low capacity over time, while 9 improved their capacity. Seventeen countries, including 7 countries with established capacity, continuously had relatively high capacity over time. International support was scarce in the majority of Asian developing countries with the most capacity building needs. Improvements in basic technical capacity available for GHG inventory preparation, such as statistics and the scientific expertise, were found to be a key necessity for countries to respond to the PA’s enhanced transparency framework. Based on these findings, the study recommended increasing support for improvements in basic technical capacity, especially in countries where existing capacity is low and support is limited. Such capacity building efforts are also beneficial for countries to form and implement nationally determined contributions (NDCs) and other economic and development policies.

Best Practice for Transitioning from Carbon Dioxide (CO2) Enhanced Oil Recovery EOR to CO2 Storage

The purpose of Carbon Capture and Storage (CCS) is to reduce emissions of greenhouse gases to the atmosphere as a climate change mitigation activity. However, given the relatively high costs currently associated with CCS, coupling CCS with Enhanced Oil Recovery (EOR) could provide a critical financial incentive to facilitate development of CCS projects in the near term. One issue is that projects to enhance oil production are primarily implemented to increase oil production with (tertiary recovery methods and any long term storage of CO2 is considered a potential ancillary benefit. When projects are designed as CCS from the start, there is typically a site evaluation process to review the storage formation according to best practice criteria for CCS. In EOR, the formation where CO2 would be stored is predetermined by the existing oil bearing reservoir, raising potential questions about monitoring, long-term CO2 storage liabilities, potential, leakage, permanence and other issues that must be addressed in CCS projects but may fall outside the boundaries of a typical EOR project. Finally, although this paper is premised on historical and current experiences with enhanced oil recovery projects, similar considerations could also be given to enhanced recovery of natural gas.There are no specific technological barriers or challenges in transitioning and converting a pure CO2-EOR operation into a CO2 storage operation but there are a number of legal, regulatory and economic differences which must be addressed if an EOR project is to serve as a CCS project. Lack of experience or unresolved issues related to EOR becoming CCS could create barriers unless the issues are fully understood and managed to the satisfaction of regulators. Understanding best practice and the policy and regulatory frameworks affecting CCS from EOR is an important driver for ensuring that CO2-EOR projects are developed in a manner which will enable the carbon stored to be recognised as a mitigation activity under local legislation/carbon market schemes and in national GHG inventories which support monitoring progress under the COP21 Paris Agreement.The paper provides an overview of the key issues in the USA, Canada, EU, Australia, and Brazil and provides recommendations for what companies need to do should they wish to transition from EOR to CCS for existing or future operations.

A National Greenhouse Gas Inventory Management System for South Africa

South Africa has committed to reducing its contribution to the global GHG budget. It ratified the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. The UNFCCC stipulates that Non-Annex 1 countries are required to submit inventory reports every two years as part of their Biennial Update Reports (BURs) or National Communications (NCs). To assist with this increased reporting a National GHG Inventory Management System (NGHGIS), with new internal procedures and capacities, is being developed. The NGHGIS has been designed to ensure transparency, consistency, comparability, completeness and accuracy of the GHG inventory. It ensures the quality of the inventory through planning, preparation and management of inventory activities. The NGHGIS has been set up in a web-based, collaborative platform that allows for document management, sharing and storage. The main components of the NGHGIS are the (a) organisational structure; (b) inventory preparation work plan where responsibilities are assigned; (c) data supplier and stakeholder lists; (d) input datasets (linked to the stakeholder list) providing information on required data, MOU’s, and data due dates; (e) quality assurance and quality control (QA/QC) objectives, checks, logs and tools; (f) emission calculation method statements; (g) GHG inventory outputs which include estimation files, a trend viewer and a public website; and (h) improvement plans. In addition to the web-based system, new institutional arrangements and data flows have been proposed, the legal landscape has been mapped, draft MOUs for data suppliers have been drawn up and a detailed QA/QC plan has been developed. The final stage of the NGHGIS is the development of the data collection plan and technical guidelines for the Agriculture, Forestry and Other Land Use (AFOLU) and Waste sectors. The centralised NGHGIS will reduce the loss of information, improve continuity between inventories and assist in the timely completion of inventory updates.

Spatiotemporal modeling of fuelwood environmental impacts: Towards improved accounting for non-renewable biomass

The extraction and burning of woody biomass at rates exceeding re-growth (i.e. non-renewable extraction) results in net emissions of CO2. Quantification of the amount of non-renewable woody biomass through a robust and widely applicable method is urgently needed for a wide variety of applications including cookstove carbon-offset projects, national GHG inventories, and sustainable forest management strategies under REDD+. Within this context, we developed “Mofuss” (Modeling fuelwood savings scenarios), a dynamic model that simulates the spatiotemporal effect of fuelwood harvesting on the landscape vegetation and that accounts for savings in non-renewable woody biomass from reduced consumption. The model was tested in western Honduras where collected and marketed fuelwood is used by the residential sector in both urban and rural settlements. We argue that geospatial modeling, aimed at representing real situations more closely while integrating uncertainty, should be used in calculations of carbon savings from cookstove projects or fuel switching interventions.

Models for reporting forest litter and soil C pools in national greenhouse gas inventories: methodological considerations and requirements

ABSTRACTThe compilation of GHG inventories has become a common practice to support environmental decision- and policy-making, for example in the context of the UNFCCC. To estimate GHG emissions, simulation models present viable alternatives to measured data. In order to make an informed decision on model selection, clear information on the purpose and applicability of a particular model is needed. This article discusses model requirements with respect to the suitability of estimating the carbon balance of dead wood and litter (dead organic matter; DOM) and soil in forests with a particular focus on policy needs under international processes such as the UNFCCC. Based on criteria established for GHG reporting under the UNFCCC including transparency, consistency, comparability, completeness and accuracy, this paper presents an approach to classify commonly used simulation models for estimating C budgets of DOM and soil in European forests. Among the six discussed models, the authors found a clear trend toward models for providing quantitatively precise, site-specific estimates. To meet reporting needs for national GHG inventories, the authors conclude that there is a need for models producing qualitative realistic and unbiased estimates at larger scales in a transparent and comparable manner.

국내 습지(침수지) 온실가스 배출량 산정

This study was reviewed the national greenhouse gas inventory report (NIR) of Annex I countries and estimated national greenhouse gas inventory on wetlands in Korea. Annex I countries submitted National Inventory Report which are focused on land converted to wetlands category and wetland remaining wetland (mainly peat lands) because IPCC did not suggest a formal methodology on flooded land. So we conducted a study on estimating of national greenhouse gas inventory in wetland (flooded land). The total annual <TEX>$CO_2-eq.$</TEX> emission of wetland remaining wetland (flooded land) was ranged from 99.9 Gg <TEX>$CO_2-eq.$</TEX> to 237.1 Gg <TEX>$CO_2-eq.$</TEX> from 1990 to 2012. The <TEX>$CO_2-eq.$</TEX> emissions was declined after peaking in 1995, however, it slightly increasing in recently years. The latest total <TEX>$CO_2-eq.$</TEX> emission from flooded land was 117.7 Gg <TEX>$CO_2-eq.$</TEX> in 2012 which was covered only 0.00002% of national GHG inventory. This means that flooded land is not key-category in Korea. We will consider an improvement for emissions of flooded land, if IPCC suggest formal or complementary methodology.

CO2 emissions from Iran's power sector and analysis of the influencing factors using the stochastic impacts by regression on population, affluence and technology (STIRPAT) model

ABSTRACTThe current status of CO2 emissions from Iran's power sector and the socio-economic factors that influence these emissions are fully covered in this paper. To begin, the amount of CO2 emissions is calculated based on the IPCC guidelines for national GHG inventories. The analysis of socio-economic influencing parameters is performed by the stochastic impacts by regression on population, affluence and technology (STIRPAT) model using population size, gross domestic product (GDP) per capita, electricity intensity and consumption of energy resources for electricity generation. Then CO2 emissions related to the electricity consumption in six sectors (residential, industrial, public, agriculture, trade and lighting) as well as grid losses and internal electricity consumption of power plants are estimated. Finally, CO2 emissions from Iran's power sector are compared with their alternatives in Turkey and China. The results indicate that CO2 emissions increased from 78.778 Tg in 2003 to 149.691 Tg in 2013, and the average CO2 specific emission factor is 571.29 g/kWh. The outputs of the STIRPAT model illustrate that population size, GDP per capita, electricity intensity and the consumption of fossil fuels for electricity generation positively influence CO2 emissions, while electricity generation by hydropower, renewable energies and nuclear energy negatively do.

Counting the non-CO&lt;SUB align="right"&gt;2 diversion of biogenic carbon: an improvement suggested for the UNFCCC methodology

UNFCCC has developed a software to support non-Annex I parties for preparation of their national GHG inventories. This paper identifies a weakness in the software on double counting of some GHG emissions. Most of the biogenic activities, livestock, rice cultivation, use of biomass, etc. are carbon neutral. However, these activities emit CH4 and CO consuming atmospheric CO2. The UNFCCC software counts CH4 and CO emissions without adjusting the consumed CO2. GHG inventory of Pakistan was prepared for the year 2008 with the help of this software and guidelines of Intergovernmental Panel on Climate Change. The biogenic CH4 emissions, 34% of the 2008 GHG inventory, consumed 3.16 million tonnes of atmospheric carbon. The deduction of this carbon reduces the GHG inventory by 3.74%. This paper suggests improvements in the software to enhance the accuracy of GHG inventories.

Land dataset uncertainty: effect on Romanian National Greenhouse Gas Inventory

The availability of long-term land datasets is fundamental to ensure consistent and accurate national greenhouse gas inventories for land use and land use changes. Estimation of Romania’s CO2 removals and emissions over 1970-2010 was assessed comparatively by using National Statistics (as reference dataset), Corine Land Cover data, as well as four additional datasets produced from the reference dataset and assuming some forest data changes according to other available partial datasets (NFI,LUCAS or expert judgment). A spreadsheet, implementing a model of UNFCCC national greenhouse gas inventory, allowed estimation of both net CO2 removals and emissions and gross CO2 fluxes from all carbon pools, for all land subcategories over 1970-2010. The model was run for each dataset. The reference dataset resulted in an average annual gross flux of CO2, twice as large as the corresponding annual net removals of 13 TgCO2, while annual estimates were more than double in post-1990 compared to pre - 1990. Uncertainty of net annual CO2 removals by reference dataset was estimated around 31 %, slightly lower than for gross estimate, and just around 55% when based on CLC dataset. Overall, the contribution of 12 broad land sub-categories to CO2 inventory was similar in the national net and gross estimates, for both pre- and post-1990 periods. Land under conversion represented 9% of the country’s area in pre- and only 2% in post-1990, corresponding to an annual average of 28% of gross and 6% of net annual CO2 estimates. Among the choices of datasets tested, the reference dataset provided the most conservative estimates of the CO2 inventory. Other datasets generally overestimated annual LULUCF sink and its main contributor forestland, as well as the emissions or removals from land conversion. Compared to pre-1990, when annual sink was rather low, land abandonment and moderating management in the post-1990 period has led to an increase of C stock in all pools, showing the relevance of political changes on land’s CO2 emissions/removals. Inconsistency within available land datasets impairs more accurate estimation of national GHG inventory. The development of an improved land use assessment system around National Forest Inventory is therefore suggested as a solution to implement consistent land definitions and to accurately estimate their areas in time.

The Effect of a Consumption-Based Accounting Method in National GHG Inventories: A Trilateral Trade System Application

The allocation of emissions embodied in international trade is crucial to evaluate the real impact of countries in the climate change and their responsibility in greenhouse gas emissions. In this paper we apply a new theoretical framework that allocates the emissions embodied in international trade and computes the consequent carbon transferred across countries, according to a consumption-based accounting. The method uses the value of goods traded internationally and the respective carbon intensity as a average national emissions coefficient.. We analyze a trilateral trade system composed by Sweden, Italy and Poland during the period 2000-2008. We find that, with respect to the conventional greenhouse gas national inventory schemes, consumption-based accounting implies an increase of Italian and Swedish emission responsibility by 1.4% and 11.8%, respectively, and a decrease of Polish one by 2.81%. We also assess the relevance of this framework at the sectoral level by hypothesizing a shift of Italian imports of Machinery and Transport Equipment from Poland to Sweden. We deduce that, through appropriate policies, importer nations could be encouraged to find producers with the best environmental performances while exporter nations could be induced to reduce their carbon intensity to stimulate the international demand for their goods. Finally, we discuss some policy implications deriving from the application of the consumption-based accounting. The analysis performed in the paper suggests that the consumption-based accounting could be an important tool in the climate change challenge to reduce global emissions.

Development of National Greenhouse Gas Emissions Inventories in the Context of International Climate Negotiations

Based on the principle ofcommon but differentiated responsibilities, the UNFCCC has different requirements on national GHG inventories submitted by Annex I and non-Annex I parties. Since 2007, the transparency of mitigation actions by developing countries, the submission frequency of national communications cored on national inventory and the relevant international consultation and analysis have become the key issues in climate negotiations. Relevant responsibilities of developing countries showed an increasing trend. Through the analysis of these different requirements, particularly on technical review system of national inventories on developed countries and of the current situation of China’s inventory development, the challenges faced by China are identified and the corresponding countermeasures are also put forward, including improving institutional arrangements and statistic system, building country-specific and comprehensive database and preparing for time-series inventory development. CitationZhu, S.-L., and W.-T. Wang, 2013: Development of national greenhouse gas emissions inventories in the context of international climate negotiations. Adv. Clim. Change Res.,4(1), doi: 10.3724/SP.J.1248.2013.060.

IPCC 가이드라인을 이용한 국내 철도수송에 따른 온실가스 배출량 산정에 관한 연구

최근 선진국을 중심으로 2020년 이후의 신 기후변화체제에 대한 합의가 도출되면서 정부의 온실가스 저감정책은 구체적인 성과를 확보하기 위한 방향으로 빠르게 전환되고 있다. 특히 부문별 온실가스 감축목표 할당에 따라 수송부문의 저감방안은 고효율 에너지 소비 차량의 개발도 필요하지만 기존의 대중교통체계에서 저탄소 교통수단인 철도의 역할을 강조하고 있다. 따라서 향후 지속적으로 철도수송에 따른 온실가스 배출량을 관리하기 위해서는 체계적인 산정방법의 정립이 요구된다. 본 연구에서는 국가 온실가스 인벤토리 작성을 위한 2006 IPCC 가이드라인을 토대로 철도수송의 온실가스 배출원에 따라 Tier별 배출량 산정방법을 정의하였다. 또한 최근 3년(2008-2010) 동안의 철도수송에 따른 디젤 및 전력소비량을 기반으로 활동도 자료를 수집하여 Tier 1 수준에서의 온실가스 배출경향을 살펴보았다. 그 결과, 2010년 온실가스 총 배출량은 약 206만톤 <TEX>$CO_2e$</TEX>이었으며, 이 중 전력소비량이 73%를 차지하고, 디젤연료 소비량이 27%를 기여하였다. 향후 철도수송의 온실가스 저감방안을 도출하기 위해서는 다양한 운행패턴 인자를 반영한 Tier 3 수준의 배출량 산정 관리를 토대로 보다 세부적인 배출경향에 대한 파악이 필요하며, 이를 위해서는 무엇보다 배출계수의 개발이 선행되어야 할 것이다. Recently, new climate change mechanism after 2020 year has been accepted with the parties, and so government is pushing ahead the GHG reduction policies to achieve the effective results. Especially, it is essential to enhance the role of railroad in the public traffic system as well as to develop new cars with high energy efficiency for the GHG reduction of transportation sector. Thus, the calculation method of GHG emission of railroad should be established to manage the emission continuously. In this study, the calculation method of GHG emission of railroad was defined with Tier level considering its emission sources to refer to 2006 IPCC guideline for national GHG inventories. Also, the GHG emission of railroad at Tier 1 level was investigated using the activity data related to the amount of diesel and electricity consumption from 2008 to 2010. As a result, total GHG emission in 2010 was about 2,060 thousands ton CO2e, which have 73% of electricity and 27% of diesel. In future, the plans on the GHG reduction of railroad will be accomplished by the analysis of the detailed trends on the basis of the emission management of Tier 3 level under operating patterns. Therefore, it is important to develop the specific GHG emission factors of railroad in advance.

National Greenhouse Gas Emissions Inventory – Romania

As a Party to the United Nations Framework Convention on Climate Change (UNFCCC), and its Kyoto Protocol, Romania is required to elaborate, regularly update and submit the national GHG Inventory. In compliance with the reporting requirements, Romania submitted in 2010 its ninth version of the National Inventory Report (NIR) covering the national inventories of GHG emissions/removals for the period 1989-2008. The inventories cover all sectors: Energy, Industrial Processes, Solvent and other product use, Agriculture, LULUCF and Waste. The direct GHGs included in the national inventory are: Carbon dioxide (CO2); Methane (CH4); Nitrous oxide (N2O); Hydrofluorocarbons (HFCs); Perfluorocarbons (PFCs); Sulphur hexafluoride (SF6). &#x0D; The emissions trend over the 1989-2008 period reflects the changes characterized by a process of transition to a market economy. With the entire economy in transition, some energy intensive industries reduced their activities and this is reflected in the GHG emissions reduction. Energy represents the most important sector in Romania, accounting for about 69% of the total national GHG emissions in 2008.&#x0D; The most significant anthropogenic greenhouse gas is the carbon dioxide. The decrease of CO2 emissions is caused by the decline of the amount of fossil fuels burnt in the energy sector, as a consequence of activity decline.&#x0D; According to the figures, there is a great probability for Romania to meet the Kyoto Protocol commitments on the limitation of the GHG emissions in the 2008-2012 commitment period.

An approach to estimate carbon stocks change in forest carbon pools under the UNFCCC: the Italian case

Abstract: Under the UNFCCC, Annex I Parties must report annually a National GHG Inventories of anthropogenic emissions by sources and removals by sinks. LULUCF is one of the six sectors of the inventory: in this sector any emissions and removals of GHGs by land management should be reported, included the large GHGs fluxes generated by forest management and land-use changes into and from forest. In this context every Party has to produce a proper model in order to be able to fulfil GHGs Inventory request for forest sector. Taking Italy as a study case, the paper aims at presenting a new methodology for updating stock changes for years between national forest inventories, in order to reproduce annual stock changes in the five UNFCCC forest carbon pools, following the UNFCCC requirements in the context of carbon reporting.

Factors affecting the uncertainty of sinks and stocks of carbon in Finnish forests soils and vegetation

Monitoring and transparent reporting of forest carbon sinks are currently needed under the Climate Convention. From 2005 onwards, national GHG inventories should also provide uncertainty estimates of the reported emissions and removals. Comprehensive uncertainty analysis and key category analysis of the carbon inventory can provide guidance for prioritizing efforts in further development of the inventory. In this study, the estimates of the forest carbon stock and carbon sink were obtained by combining forest inventory data, models of biomass and turnover, and a dynamic decomposition model for SOM and litter, Yasso. To study the decisive factors affecting uncertainties of forest carbon sink and stock estimates, we conducted a Monte Carlo analysis for the calculation of the forest carbon budget of Finnish forests for the period 1989–2004. Uncertainty of the vegetation carbon sink was affected mostly by input data on growth variation and drain. Uncertainty of the soil carbon sink was dominated by the soil model initialization, but the effect decreased with time. After few years, the effect of initialization leveled with the effect of temperature and drain, both of which were given as input data to the system and which varied inter-annually. The contribution of these variables was less important to uncertainty of stocks in vegetation and soil than the contribution of model parameters. The most influential parameters for vegetation C stock were carbon density and conversion factors for tree and ground vegetation biomass, and for soil C stock, they were soil model parameters, and biomass conversion factors and turnover rates of fine roots and ground vegetation. After short initialization period for soil C, uncertainty of soil sink can be reduced by improving the precision of input data (harvests on upland soils, annual temperature). Precision of vegetation sink can be improved mainly by improving the quality of input data on growth variation and harvests. There is an unknown error source related to inter-annual variability of the forest ecosystems, which cannot be represented with the system. Vegetation sink was compiled with biomass models that are based on long-term averages and they do not support year-to-year variations which may occur in forest ecosystems. Averaged biomass models with averaged turnover models, produce highly auto-correlated series of litter input, which result in relatively precise annual soil sink estimates. Due to these reasons, the current inventory-based approach is more justified for the estimation of average sinks for longer periods than 1 year.

Assessment of GHG inventories from the LUCF sector of Annex-I countries

Reporting of CO2 emissions and removals from the landuse change and forestry (LUCF) sector is assessed in this paper based onthe National GHG inventories and the National Communications submittedby the Annex-I countries. LUCF sector is a net sink for 27 countries outof 31 countries and a source for Australia, Estonia, Lithuania and UnitedKingdom. LUCF sector for Annex-I countries, as a group is a net sink of2035 Tg CO2 (555 Tg Carbon). The sink feature is largely due toCO2 removal by the existing forests, plantations and other trees.Forest and grassland conversion (deforestation) is not a major source ofCO2 in the Annex-I countries. Many Annex-I countries have notfully adopted the reporting format of IPCC limiting the comparability andtransparency. Several Annex-I countries have modified the CO2emission/removal estimates for 1990, but have not explained the reasons.Reporting of uncertainty is very limited. The methods adopted andparticularly reporting is inadequate to meet the requirements foroperationalising the Kyoto Protocol articles relevant to LUCF;comparability, transparency and verifiability.