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The uncertainty of reported greenhouse gases emission inventories obtained by the aggregation of partial emissions from all sources and estimated to date for several countries is very high in comparison with the countries’ emissions limitation and reduction commitments under the Kyoto Protocol. Independent calculation of the estimates could confirm or question the undertainty estimates values obtained thus far. One of the aims of this paper is to propose statistical signal processing methods to enable calculation of the inventory variances. The annual reported emissions are used and temporal smoothness of the emissions curve is assumed. The methods considered are: a spline-function-smoothing procedure; a time-varying parameter model; and the geometric Brownian motion model. These are validated on historical observations of the CO2 emissions from fossil fuel combustion. The estimates of variances obtained are in a similar range to those obtained from national inventories using TIER1 or TIER2. Additionally, some regularities in the observed curves were noticed. [ABSTRACT FROM AUTHOR]

Emissions trading in the European Union (EU), covering the least uncertain emission sources of greenhouse gas emission inventories (CO2 from combustion and selected industrial processes in large installations), began in 2005. During the first commitment period of the Kyoto Protocol (2008–2012), the emissions trading between Parties to the Protocol will cover all greenhouse gases (CO2, CH4, N2O, HFCs, PFCs, and SF6) and sectors (energy, industry, agriculture, waste, and selected land-use activities) included in the Protocol. In this paper, we estimate the uncertainties in different emissions trading schemes based on uncertainties in corresponding inventories. According to the results, uncertainty in emissions from the EU15 and the EU25 included in the first phase of the EU emissions trading scheme (2005–2007) is ±3% (at 95% confidence interval relative to the mean value). If the trading were extended to CH4 and N2O, in addition to CO2, but no new emissions sectors were included, the tradable amount of emissions would increase by only 2% and the uncertainty in the emissions would range from −4 to +8%. Finally, uncertainty in emissions included in emissions trading under the Kyoto Protocol was estimated to vary from −6 to +21%. Inclusion of removals from forest-related activities under the Kyoto Protocol did not notably affect uncertainty, as the volume of these removals is estimated to be small. [ABSTRACT FROM AUTHOR]

World primary energy demand increases with increases in population and economic development. Within the last 25 yr, the total energy consumption has almost doubled. For the purpose of meeting this demand, fossil energy sources are used and various pollutants are generated. CO2 is also one of these gases, which cannot be removed like other pollutants, and it causes greenhouse effect and climate change. Reducing the CO2 emission is very important because of the environmental concerns and regulations, especially the Kyoto Protocol. This paper reviews the estimated world carbon emissions, Turkey's situation in electrical energy production, emission amounts estimated until the year 2020 and emission factors for dust, SO2, NOx and CO2. The estimated results show that CO2 emissions from thermal power plants in Turkey will make about 0.66 % of the global CO2 emissions in 2020. [ABSTRACT FROM AUTHOR]

This paper considers how regional greenhouse gas emission inventories can be determined. It presents a greenhouse gas emissions inventory, by source, for the East Midlands that has been compiled as part of a regional study into climate change impacts in the United Kingdom. This has used available local data, and national emissions data with appropriate scaling factors. Total greenhouse gas emissions for the region are estimated to be 59 million tonnes of carbon dioxide equivalent (CO2 equivalent) for 1997. Of these emissions, approximately 86% were carbon dioxide emissions, 7% methane emissions, and 5% were nitrous oxide, with emissions of hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6) contributing less than 2% of total emissions. [ABSTRACT FROM AUTHOR]

This study presents the experimental results obtained during long-term operation of two biofilters treating two alcohols: methanol and ethanol. The biofilters used for this purpose were previously packed with a compost material made from tobacco processing residues. The alcohols concentrations tested lay between 0.40 and 3.20 g/m3 for methanol, and 0.55 and 5.05 g/m3 for ethanol. The empty bed residence time in each biofilter was 60 s. Biofilter inlet loads of less than 190 and 300 g/m3/h for the methanol and ethanol additions respectively, were thereafter evaluated. In addition, the concentrations of nutrient nitrogen were also varied, from 0.1 to 2.0 g-N/l and from 0.3 to 11.3 g-N/l for the ethanol and the methanol, respectively. The results thus obtained have made it possible to select the optimal nitrogen concentrations which, for the cases examined, turn out to be 0.3 g-N/l and between 2 and 3.8 g-N/l for the ethanol and methanol substrates, respectively. The maximum elimination capacities obtained in this study were 82 and 150 g/m3/h, respectively for the methanol and ethanol cases. It was therefore concluded that, for a readily biodegradable compound such as ethanol, the nitrogen requirement is substantially lower than that needed for the methanol degradation, the latter appearing to be more difficult to degrade biologically under similar operating conditions. The production rate of the co-product carbon dioxide during methanol and ethanol biofiltration was also investigated. Also, a good correlation was found to exist between the temperature and the conversion achieved in the biofilter. [ABSTRACT FROM AUTHOR]

A dynamic model of the carbon budget of an oak forest ecosystem that takes into account forest stand age was developed. A numerical experiment was designed to simulate the afforestation process, and a Monte Carlo simulation was performed to determine how parameter uncertainties and environmental variability influence the result. It was found that while the total amount of carbon stored in the ecosystem increases from 1.9 kg C/m2 to 4.4 kg C/m2 over the following 20 years, the relative standard deviation increases from 9 to 21%. The contribution of varying climate and carbon dioxide parameters to total uncertainty is substantial; for example, the standard deviation at the 10th modeling year for phytomass doubles and the uncertainties of the soil pool and total accumulated carbon increase by a factor of nearly 1.4, while the uncertainty of the litter pool stays almost at the same level. [ABSTRACT FROM AUTHOR]

Changes in concentrations of soluble reactive phosphorus (SRP), excess partial pressure of carbon dioxide (EpCO2), and chlorophyll-a were examined for two rivers in the in the upper Thames catchment: the main river Thames at Wallingford and a chalk stream tributary, the River Kennet. Sampling began in the spring of 1997 and has covered extremes in river flow conditions. During the sampling period there was a dramatic reduction in phosphorus (P) inputs from the introduction of effluent P-treatment at sewage treatment works, as a result of the EU Urban Wastewater Treatment Directive. Despite major reductions in baseflow SRP concentrations in the River Kennet, from around 700 μg-P L-1 to around 100 μg-P L-1, observations of aquatic plant communities indicate overall degradation in ecological quality since effluent P-treatment was introduced. The degradation was associated with a spring and summer decline in growth of Ranunculus, a macrophyte of high conservation value in chalk streams, particularly from 2000 onwards, linked to shading by epiphytic algae. Although the EpCO2 records indicate a reduction in primary productivity since effluent P-treatment, the River Kennet may have become more sensitive to epiphyte blooms. Episodes of epiphyte proliferation appear to be linked temporally to small increases in SRP concentrations (typically above a 100 μg-P L-1 threshold) under summer baseflow conditions. The in-stream system is highly complex and individual processes and causality are difficult to resolve, particularly given changes in river flows linked to background climatic variability and limited availability of biological data. This study demonstrates the need for integrated long-term biological and chemical monitoring of river systems subject to major perturbations to assess timescales required to produce new dynamic equilibria in ecosystem response. [ABSTRACT FROM AUTHOR]