non-CO2 Greenhouse Gas Emissions Research Articles

Historical advances in the study of global terrestrial soil organic carbon sequestration

This paper serves two purposes: it provides a summarized scientific history of carbon sequestration in relation to the soil-plant system and gives a commentary on organic wastes and SOC sequestration. The concept of soil organic carbon (SOC) sequestration has its roots in: (i) the experimental work of Lundegårdh, particularly his in situ measurements of CO2 fluxes at the soil-plant interface (1924, 1927, 1930); (ii) the first estimates of SOC stocks at the global level made by Waksman [Waksman, S.A., 1938. Humus. Origin, Chemical Composition and Importance in Nature, second ed. revised. Williams and Wilkins, Baltimore, p. 526] and Rubey [Rubey, W.W., 1951. Geologic history of sea water. Bulletin of the Geological Society of America 62, 1111-1148]; (iii) the need for models dealing with soil organic matter (SOM) or SOC dynamics beginning with a conceptual SOM model by De Saussure (1780-1796) followed by the mathematical models of Jenny [Jenny, H., 1941. Factors of Soil Formation: a System of Quantitative Pedology. Dover Publications, New York, p. 288], Hénin and Dupuis [Hénin, S., Dupuis, M., 1945. Essai de bilan de la matière organique. Annales d'Agronomie 15, 17-29] and more recently the RothC [Jenkinson, D.S., Rayner, J.H., 1977. The turnover of soil organic matter in some of the Rothamsted classical experiments. Soil Science 123 (5), 298-305] and Century [Parton, W.J., Schimel, D.S., Cole, C.V., Ojima, D.S., 1987. Analysis of factors controlling soil organic matter levels in great plains grasslands. Soil Science Society of America Journal 51 (5), 1173-1179] models. The establishment of a soil C sequestration balance is not straightforward and depends greatly on the origin and the composition of organic matter that is to be returned to the system. Wastes, which are important sources of organic carbon for soils, are taken as an example. For these organic materials the following factors have to be considered: the presence or absence of fossil C, the potential of direct and indirect emissions of non-CO2 greenhouse gases (CH4 and N2O) following application and the agro-system which is being used as a comparative reference.

Soil management practices for sustainable agro-ecosystems

A doubling of the global food demand projected for the next 50 years poses a huge challenge for the sustainability of both food production and global and local environments. Today’s agricultural technologies may be increasing productivity to meet world food demand, but they may also be threatening agricultural ecosystems. For the global environment, agricultural systems provide both sources and sinks of greenhouse gases (GHGs), which include carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). This paper addresses the importance of soil organic carbon (SOC) for agro-ecosystems and GHG uptake and emission in agriculture, especially SOC changes associated with soil management. Soil management strategies have great potential to contribute to carbon sequestration, since the carbon sink capacity of the world’s agricultural and degraded soil is 50–66% of the historic carbon loss of 42–72 Pg (1 Pg=1015 g), although the actual carbon storage in cultivated soil may be smaller if climate changes lead to increasing mineralization. The importance of SOC in agricultural soil is, however, not controversial, as SOC helps to sustain soil fertility and conserve soil and water quality, and organic carbon compounds play a variety of roles in the nutrient, water, and biological cycles. No-tillage practices, cover crop management, and manure application are recommended to enhance SOC storage and to contribute to sustainable food production, which also improves soil quality. SOC sequestration could be increased at the expense of increasing the amount of non-CO2 GHG emissions; however, soil testing, synchronized fertilization techniques, and optimum water control for flooding paddy fields, among other things, can reduce these emissions. Since increasing SOC may also be able to mitigate some local environmental problems, it will be necessary to have integrated soil management practices that are compatible with increasing SOM management and controlling soil residual nutrients. Cover crops would be a critical tool for sustainable soil management because they can scavenge soil residual nitrogen and their ecological functions can be utilized to establish an optimal nitrogen cycle. In addition to developing soil management strategies for sustainable agro-ecosystems, some political and social approaches will be needed, based on a common understanding that soil and agro-ecosystems are essential for a sustainable society.

Competitiveness of terrestrial greenhouse gas offsets: are they a bridge to the future?

Activities to reduce net greenhouse gas emissions by biological soil or forest carbon sequestration predominantly utilize currently known, readily implementable technologies. Many other greenhouse gas emission reduction options require future technological development or must wait for turnover of capital stock. Carbon sequestration options in soils and forests, while ready to go now, generally have a finite life, allowing use until other strategies are developed. This paper reports on an investigation of the competitiveness of biological carbon sequestration from a dynamic and multiple strategy viewpoint. Key factors affecting the competitiveness of terrestrial mitigation options are land availability and cost effectiveness relative to other options including CO2 capture and storage, energy efficiency improvements, fuel switching, and non-CO2 greenhouse gas emission reductions. The analysis results show that, at lower CO2 prices and in the near term, soil carbon and other agricultural/forestry options can be important bridges to the future, initially providing a substantial portion of attainable reductions in net greenhouse gas emissions, but with a limited role in later years. At higher CO2 prices, afforestation and biofuels are more dominant among terrestrial options to offset greenhouse gas emissions. But in the longer run, allowing for capital stock turnover, options to reduce greenhouse gas emissions from the energy system and biofuels provide an increasing share of potential reductions in total US greenhouse gas emissions.

Multigas Mitigation: An Economic Analysis Using GRAPE Model

Future global warming may depend strongly on the potential for abating emissions of greenhouse gases (GHGs). Flexibility in implementing climate change mitigation policies can significantly reduce mitigation costs and has three dimensions; space, time and gas species. Therefore, multiple greenhouse gas reduction flexibility should be considered. The emission and reduction potential of CO2 and non-CO2 GHGs are assessed here using an integrated assessment model under climate change targets. The implications on gas life as well as abatement timing uncertainty on costs, technological availability, etc. are discussed. The introduction of additional multigas reductions will cut the economic burden of achieving a given climate change target. The conclusions are threefold; (1) Multigas mitigation is a cost effective strategy compared to CO2-only mitigation under the same climate target, (2) CO2 mitigation is expected to lead to ancillary reductions in CH4, N2O and SOx emissions, and (3) There is great uncertainty in the assessment of non-CO2 GHG mitigation opportunities.

Developing Canada's National Forest Carbon Monitoring, Accounting and Reporting System to Meet the Reporting Requirements of the Kyoto Protocol

The rate of carbon accumulation in the atmosphere can be reduced by decreasing emissions from the burning of fossil fuels and by increasing the net uptake (or reducing the net loss) of carbon in terrestrial (and aquatic) ecosystems. The Kyoto Protocol addresses both the release and uptake of carbon. Canada is developing a National Forest Carbon Monitoring, Accounting and Reporting System in support of its international obligations to report greenhouse gas sources and sinks. This system employs forest-inventory data, growth and yield information, and statistics on natural disturbances, management actions and land-use change to estimate forest carbon stocks, changes in carbon stocks, and emissions of non-CO2 greenhouse gases. A key component of the system is the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS). The model is undergoing extensive revisions to enable analyses at four spatial scales (national, provincial, forest management unit and stand) and in annual time steps. The model and the supporting databases can be used to assess carbon-stock changes between 1990 and the present, and to predict future carbon-stock changes based on scenarios of future disturbance rates and management actions.

Nitrogen Oxide and Methane Emissions under Varying Tillage and Fertilizer Management

Comprehensive assessment of the total greenhouse gas (GHG) budget of reduced tillage agricultural systems must consider emissions of nitrous oxide (N2O) and methane (CH4), each of which have higher global warming potentials than carbon dioxide (CO2). Tillage intensity may also impact nitric oxide (NO) emissions, which can have various environmental and agronomic impacts. In 2003 and 2004, we used chambers to measure N2O, CH4, and NO fluxes from plots that had been managed under differing tillage intensity since 1991. The effect of tillage on non-CO2 GHG emissions varied, in both magnitude and direction, depending on fertilizer practices. Emissions of N2O following broadcast urea (BU) application were higher under no till (NT) and conservation tillage (CsT) compared to conventional tillage (CT). In contrast, following anhydrous ammonia (AA) injection, N2O emissions were higher under CT and CsT compared to NT. Emissions following surface urea ammonium nitrate (UAN) application did not vary with tillage. Total growing season non-CO2 GHG emissions were equivalent to CO2 emissions of 0.15 to 1.9 Mg CO2 ha(-1) yr(-1) or 0.04 to 0.53 Mg soil-C ha(-1) yr(-1). Emissions of N2O from AA-amended plots were two to four times greater than UAN- and BU-amended plots. Total NO + N2O losses in the UAN treatment were approximately 50% lower than AA and BU. This study demonstrates that N2O emissions can represent a substantial component of the total GHG budget of reduced tillage systems, and that interactions between fertilizer and tillage practices can be important in controlling non-CO2 GHG emissions.

Evaluation of non-CO2-greenhouse gas emission reductions in the Netherlands in the period 1990–2003

In the Netherlands, several measures were implemented to curb the emissions of non-CO2 greenhouse (NCG) gases in the period 1990–2003. Without the implementation of these reduction measures, emissions of NCG gases in 2003 would have been 11 million tonnes of CO2-eq. higher. Policies which were already in place before specific NCG gas policies were introduced, are predominantly responsible for the reductions achieved so far. Roughly 80% of the achieved reductions in the Netherlands can be attributed to these policies, and 20% to a specific Dutch Reduction Plan on NCG gases that was introduced in 2000. Our analysis shows that the policies in place in the period 1990–2003 were very economical from the government point of view: almost half of the emission reductions can be achieved against costs below 5 euro per tonne CO2-eq. Whereas, for example, the cost-effectiveness of government CO2 reduction programmes in the housing sector ranged from 4 to over 300 euro per tonne of CO2-eq. in the period 1995–2002.

Emission of non CO2 greenhouse gases from landfills of different age located in central Italy

Landfill gas is a product of the natural biological decomposition of organic material contained in wastes deposited in landfills. This denomination generically indicates a gas mixture made of methane and carbon dioxide. These gases are produced until most of the organic material in the waste has been degraded. Emissions from municipal landfill sites are therefore potentially harmful to both local and global air quality; the global emissions of an important greenhouse gas such as methane are estimated to be between 20 and 70 Tg year−1. Moreover, landfills have been shown to be a major source of anthropogenic halogenated greenhouse gases such as chlorofluorocarbons (CFCs) and their hydrogenated substitutes (HCFCs, HFCs). These long-living gases are emitted into the atmosphere as a consequence of leakage occurring in landfills where chlorine containing equipment and materials have been dumped. In this study, municipal landfills of different ages located in Tuscany (central Italy) have been investigated. Grab samples, collected at gas collection facilities, were analysed in gas chromatography with flame ionization detection for major gas measurements and in gas chromatography-mass spectrometry for halocarbon measurements. Furthermore, fluxes from the landfill surface were measured by means of a flux chamber. This approach allows an estimation of the total yearly emissions of non-CO2 greenhouse gases from a landfill.

A study of environmental and management drivers of non-CO2 greenhouse gas emissions in Australian agro-ecosystems

Australian climate, soils and agricultural management practices are significantly different from those of the northern hemisphere nations. Consequently, experimental data on greenhouse gas production from European and North American agricultural soils and its interpretation are unlikely to be directly applicable to Australian systems. A programme of studies of non-CO2 greenhouse gas emissions from agriculture has been established that is designed to reduce uncertainty of non-CO2 greenhouse gas emissions in the Australian National Greenhouse Gas Inventory and provide outputs that will enable better on-farm management practices for reducing non-CO2 greenhouse gas emissions, particularly nitrous oxide. The systems being examined and their locations are irrigated pasture (Kyabram Victoria), irrigated cotton (Narrabri, NSW), irrigated maize (Griffith, NSW), rain-fed wheat (Rutherglen, Victoria) and rain-fed wheat (Cunderdin, WA). The field studies include treatments with and without fertilizer addition, stubble burning versus stubble retention, conventional cultivation versus direct drilling and crop rotation to determine emission factors and treatment possibilities for best management options. The data to date suggest that nitrous oxide emissions from nitrogen fertilizer, applied to irrigated dairy pastures and rain-fed winter wheat, appear much lower than the average of northern hemisphere grain and pasture studies. More variable emissions have been found in studies of irrigated cotton/vetch/wheat rotation and substantially higher emissions from irrigated maize.

Greenhouse gas implications of household energy technology in Kenya.

Linkages between household energy technology, indoor air pollution, and greenhouse gas (GHG) emissions have become increasingly important in understanding the local and global environmental and health effects of domestic energy use. We report on GHG emissions from common Kenyan wood and charcoal cookstoves. Our estimations are based on 29 d of measurements under the conditions of actual use in 19 rural Kenyan households. Carbon monoxide (CO), particulate matter (PM10), combustion phase, and fuel mass were measured continuously or in short intervals in day-long monitoring sessions. Emissions of pollutants other than CO and PM10 were estimated using emissions ratios from published literature. We estimated that the daily carbon emissions from charcoal stoves (5202 +/- 2257 g of C: mean +/- SD) were lower than both traditional open fire (5990 +/- 1843 g of C) and improved ceramic woodstoves (5905 +/- 1553 g of C), but the differences were not statistically significant. However, when each pollutant was weighted using a 20-yr global warming potential, charcoal stoves emitted larger amounts of GHGs than either type of woodstove (9850 +/- 4600 g of C for charcoal as compared to 8310 +/- 2400 and 9649 +/- 2207 for open fire and ceramic woodstoves, respectively; differences not statistically significant). Non-CO2 emissions from charcoal stoves were 5549 +/- 2700 g of C in 20-yr CO2 equivalent units, while emissions were 2860 +/- 680 and 4711 +/- 919 for three-stone fires and improved ceramic stoves, respectively, with statistically significant results between charcoal and wood stoves. Therefore in a sustainable fuel-cycle (i.e., excluding CO2), charcoal stoves have larger emissions than woodstoves. When the emissions from charcoal production, measured in a previous study, were included in the assessment, the disparity between the GHG emissions from charcoal and firewood increased significantly, with non-CO2 GHG emissions factors (g of C/kg of fuel burned) for charcoal production and consumption 6-13 times higher than emissions from woodstoves. Policy implications and options for environment and public health are discussed.

Economic Development and Emission Control over the Long Term: The ICLIPS Aggregated Economic Model

In integrated assessments of climate change, greenhouse-gasemissions and climate change impacts provide the linkages betweenthe world economy and the climate system. Key climatic processesoperate at the scales of centuries. This requires highlyaggregated models for portraying the dynamics of the economicsystem. An extended Ramsey-type optimal growth model is presentedas the appropriate tool to be integrated with a reduced-formclimate model in the ICLIPS integrated assessment. Theeleven-region model of the world economy involves exogenouspopulation and endogenous investment dynamics with productivityprogress based on a technological diffusion model. World regionsare linked via intertemporal trade flows of the compositeconsumption/investment good, capital mobility, and emission permittrading. Coupled with the ICLIPS Climate Model, the AggregatedEconomic Model can determine corridors of permitted long-termcarbon emission paths or, as primarily discussed in this paper,specific cost-effective emission trajectories. The sensitivity ofmitigation costs to externally specified climate change/impactconstraints and to assumptions about non-CO2 greenhouse-gasemissions is also discussed.

Responsibility for past and future global warming: Uncertainties in attributing anthropogenic climate change

During the negotiations on the Kyoto Protocol, Brazil proposed a methodology to link the relative contribution of Annex I Parties to emission reductions with the relative contributions of Parties to the global-mean temperature increase. The proposal was not adopted during the negotiations but referred to the Subsidiary Body for Scientific and Technological Advice for consideration of its methodological aspects. In this context we analyze the impact of model uncertainties and methodological choices on the regionally attributed global-mean temperature increase. A climate assessment model has been developed to calculate changes in greenhouse gas concentrations, global-mean temperature and sea-level rise attributable to individual regions. The analysis shows the impact of the different choices in methodological aspects to be as important as the impact of model uncertainties on a region's contribution to present and future global temperature increases. Choices may be the inclusion of the anthropogenic non-CO2 greenhouse gas emissions and/or theCO2 emissions associated with land-use changes. When responsibility to global temperature change is attributed to all emitting Parties, the impacts of modeling uncertainties and methodological choices on contributions of individual Parties are considerable. However, if relative contributions are calculated only within the group of Annex I countries, the results are less sensitive to the uncertainty aspects considered here.

5605647 Fluoroiodocarbon blends as CFC and halon replacements: Nimitz Jonathan S; Lankford Lance H Albuquerque, NM, United States assigned to Ikon Corporation

The emission control of non-CO2 greenhouse gases is conducive to slowing down global warming. It is also helpful in controlling environmental pollution, and beneficial in improving the local health benefits. This paper aims at six kinds of non-CO2 greenhouse gases under United Nations Framework Convention on Climate Change, namely methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6), and nitrogen trifluoride (NF3). This paper analyzes the emission status and trend of China’s non-CO2 greenhouse gases, and provides some technology selections for non-CO2 emission reduction. Through strategic policy arrangements and appropriate technology choices, China can gain environmental protection and greenhouse gas control.Zhou, Y.-M., and Y.-S. Feng, 2014: The strategy and technology selection for non-CO2 greenhouse gas emission control. Adv. Clim. Change Res., 5(1), doi: 10.3724/SP.J.1248.2014.028.

The African experience with the IPCC methodology for estimating greenhouse gas emissions

In order to arrive at transparent and comparable inventories, the IPCC, in cooperation with the OECD, is currently developing a common methodology and reporting guidelines for the estimation of anthropogenic greenhouse gas emissions. To gain experience with the IPCC methodology, inventories are currently being carried out in various countries. This paper describes the African experience regarding emission inventories and preliminary results of the studies. It focuses on several important sources of non-CO2 greenhouse gas emissions in Africa: biomass burning; rice cultivation; and animals.

Effectiveness of non-CO2 greenhouse gas emission reduction technologies

Non-CO2 greenhouse gases, such as methane and nitrous oxide, can make a relevant contribution to the enhanced greenhouse effect, and hence emission reduction is desirable. In emission reduction inventories, both the magnitude of the emission reduction as well as the specific emission reduction costs should be determined. The current knowledge of the potential for and costs of reducing these emissions is still limited. Taking this into account, the following results can be obtained. Methane emissions can be considerably reduced from underground coal mining, oil production, natural gas operations, landfilling of waste, and wastewater treatment. Also emissions from enteric fermentation and animal manure can be reduced substantially. The total technical potential for methane emission reduction (given the present activity level) is estimated to be about one third. The economic potential, having net negative emission reduction costs, is estimated to be about half of this value. These reductions can be attained over a period of 10 - 20 years. The technical potential for the reduction of nitrous oxide emissions is currently estimated to be less than 10% Apart from the possibility of implementing existing techniques, there seems to be considerable room for developing techniques for more far-reaching emission reductions both for methane and nitrous oxide.