Giacomo Grassi

Applying the conservativeness principle to REDD to deal with the uncertainties of the estimates

A common paradigm when the reduction of emissions from deforestations is estimated for the purpose of promoting it as a mitigation option in the context of the United Nations Framework Convention on Climate Change (UNFCCC) is that high uncertainties in input data—i.e., area change and C stock change/area—may seriously undermine the credibility of the estimates and therefore of reduced deforestation as a mitigation option. In this paper, we show how a series of concepts and methodological tools—already existing in UNFCCC decisions and IPCC guidance documents—may greatly help to deal with the uncertainties of the estimates of reduced emissions from deforestation.

Elements for the expected mechanisms on 'reduced emissions from deforestation and degradation, REDD' under UNFCCC

Carbon emissions from deforestation and degradation account for about 20% of global anthropogenic emissions. Strategies and incentives for reduced emissions from deforestation and degradation (REDD) have emerged as one of the most active areas in the international climate change negotiations under the United Nations Framework Convention on Climate Change (UNFCCC). While the current negotiations focus on a REDD mechanism in developing countries, it should be recognized that risks of carbon losses from forests occur in all climate zones and also in industrialized countries. A future climate change agreement would be more effective if it included all carbon losses and gains from land use in all countries and climate zones. The REDD mechanism will be an important step towards reducing emissions from land use change in developing countries, but needs to be followed by steps in other land use systems and regions. A national approach to REDD and significant coverage globally are needed to deal with the risk that deforestation and degradation activities are displaced rather than avoided. Favourable institutional and governance conditions need to be established that guarantee in the long-term a stable incentive and control system for maintaining forest carbon stocks. Ambitious emission reductions from deforestation and forest degradation need sustained financial incentives, which go beyond positive incentives for reduced emissions but also give incentives for sustainable forest management. Current data limitations need—and can be—overcome in the coming years to allow accurate accounting of reduced emissions from deforestation and degradation. A proper application of the conservativeness approach in the REDD context could allow a simplified reporting of emissions from deforestation in a first phase, consistent with the already agreed UNFCCC reporting principles.

National GHG emissions reduction pledges and 2°C: comparison of studies

This article provides further detail on expected global GHG emission levels in 2020, based on the Emissions Gap Report (United Nations Environment Programme, December 2010), assuming the emission reduction proposals in the Copenhagen Accord and Cancun Agreements are met. Large differences are found in the results of individual groups owing to uncertainties in current and projected emission estimates and in the interpretation of the reduction proposals. Regardless of these uncertainties, the pledges for 2020 are expected to deliver emission levels above those that are consistent with a 2°C limit. This emissions gap could be narrowed through implementing the more stringent conditional pledges, minimizing the use of ‘lenient’ credits from forests and surplus emission units, avoiding double-counting of offsets and implementing measures beyond current pledges. Conversely, emission reduction gains from countries moving from their low to high ambition pledges could be more than offset by the use of ‘lenient’ land use, land-use change and forestry (LULUCF) credits and surplus emissions units, if these were used to the maximum. Laying the groundwork for faster emission reduction rates after 2020 appears to be crucial in any case.

EU mitigation potential of harvested wood products

BackgroundThe new rules for the Land Use, Land Use Change and Forestry sector under the Kyoto Protocol recognized the importance of Harvested Wood Products (HWP) in climate change mitigation. We used the Tier 2 method proposed in the 2013 IPCC KP Supplement to estimate emissions and removals from HWP from 1990 to 2030 in EU-28 countries with three future harvest scenarios (constant historical average, and +/−20% in 2030).ResultsFor the historical period (2000–2012) our results are consistent with other studies, indicating a HWP sink equal on average to −44.0 Mt CO2 yr−1 (about 10% of the sink by forest pools). Assuming a constant historical harvest scenario and future distribution of the total harvest among each commodity, the HWP sink decreases to −22.9 Mt CO2 yr−1 in 2030. The increasing and decreasing harvest scenarios produced a HWP sink of −43.2 and −9.0 Mt CO2 yr−1 in 2030, respectively. Other factors may play an important role on HWP sink, including: (i) the relative share of different wood products, and (ii) the combined effect of production, import and export on the domestic production of each commodity.ConclusionsMaintaining a constant historical harvest, the HWP sink will slowly tend to saturate, i.e. to approach zero in the long term. The current HWP sink will be maintained only by further increasing the current harvest; however, this will tend to reduce the current sink in forest biomass, at least in the short term. Overall, our results suggest that: (i) there is limited potential for additional HWP sink in the EU; (ii) the HWP mitigation potential should be analyzed in conjunction with other mitigation components (e.g. sink in forest biomass, energy and material substitution by wood).

Can recent pan-tropical biomass maps be used to derive alternative Tier 1 values for reporting REDD+ activities under UNFCCC?

The IPCC Guidelines propose 3 Tier levels for greenhouse gas monitoring within the forest land category with a hierarchical order in terms of accuracy, data requirements and complexity. Due to missing data and/or capacities, many developing countries, potentially interested in the reducing emissions from deforestation and forest degradation scheme, have to rely on Tier 1 default values with highest uncertainties. A possible way to increase the credibility of uncertain estimates is to apply a conservative approach, for which standard statistical information is needed. However, such information is currently not available for the IPCC values. In our study we combine a recent global forest mask, an ecological zoning map and the pan-tropical AGB datasets of Saatchi and Baccini to derive mean forest AGB values per ecological zone and continent as well as their corresponding confidence intervals. Such analysis can be considered transparent as the datasets/methodologies are well documented. Our study leads to alternative Tier 1 values and allows the application of statistically-based conservative approaches. Our AGB estimates derived from Saatchi and Baccini datasets are 35% and 24% lower respectively than the IPCC values. When restricting the analysis to intact forest landscapes resulting ABG estimates derived from Saatchi and Baccini datasets get closer to the IPCC values with 13% and 1% differences respectively (underestimation). This suggests that the IPCC default values are mainly based on plots in mature forest stands. However, as tropical forests generally consist of a mixture of intact and degraded stands, the use of IPCC values may not properly reflect the reality. Finally, we propose to use the average composite of the Saatchi and Baccini datasets to produce improved alternative IPCC Tier 1 values. The values derived from such approach can easily be updated when newer and/or improved pan-tropical AGB maps will be available.

Implementing conservativeness in REDD+ is realistic and useful to address the most uncertain estimates

One of the main challenges in reducing emissions from deforestation and forest degradation(REDD+), either within a future UNFCCC approach or as part of other voluntary initiatives,is to design a system which is credible and broadly implementable by developing countries.To ensure credibility of REDD+ high quality monitoring systems are needed, i.e. capable ofproducing accurate estimates of greenhouse gas (GHG) emissions and removals. However, apossible trade-off exists between the high quality system requirement and broad participa-tion: if a significant number of countries will not fully access REDD+ because of not beingable to produce accurate estimates, the consequent risk of leakage (i.e. emissions displace-ment to these countries) could undermine the ultimate scope of REDD+.Plugge et al. (2012) analyzed the implications of applying the principle of conserva-tiveness in the context of uncertainties of carbon stock change estimates in REDD+. Whilethis principle is included in several UNFCCC documents (e.g., UNFCCC2006), itsapplication to REDD+ was proposed by Grassi et al. (2008) “to address the potentialincompleteness and high uncertainties of REDD+ estimates”;i.e.“when completeness oraccuracy of estimates cannot be achieved the reduction of emissions should not beoverestimated,oratleastthe riskofoverestimationshouldbereduced”.Wide interest hasbeenshown in this proposal (e.g., GOFC-GOLD 2012;HeroldS MeridianInstitute 2011).A key message from Plugge et al. (2012) is that, despite its attractiveness, the conserva-tiveness principle does not appear to be implementable in many cases, because it drasticallyreduces the amount of emission reductions that can be claimed (e.g. “for countries with lowdeforestation rates REDD is obviously not an option for generating benefits, as they wouldneed to implement monitoring systems that are able to estimate carbon stock changes with atotal error well below 1 %”). Similar conclusions, using a similar approach, were alsopresented in Kohl et al. (2009).We believe that this conclusion: on the impossibility for countries with low deforestationrates to generate REDD+ benefits under a conservative approach, is the consequence of theassumptions taken by these authors. In particular, some elements appear to have beenoverlooked by Plugge et al. (2012).

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

ABSTRACT The 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.

Reconciling global-model estimates and country reporting of anthropogenic forest CO 2 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.