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1.
The importance of sulfur dioxide emissions for climate change is now established, although substantial uncertainties remain. This paper presents projections for future sulfur dioxide emissions using the MiniCAM integrated assessment model. A new income-based parameterization for future sulfur dioxide emissions controls is developed based on purchasing power parity (PPP) income estimates and historical trends related to the implementation of sulfur emissions limitations. This parameterization is then used to produce sulfur dioxide emissions trajectories for the set of scenarios developed for the Special Report on Emission Scenarios (SRES). We use the SRES methodology to produce harmonized SRES scenarios using the latest version of the MiniCAM model. The implications, and requirements, for integrated assessment modeling of sulfur dioxide emissions are discussed. We find that sulfur emissions eventually decline over the next century under a wide set of assumptions. These emission reductions result from a combination of emission controls, the adoption of advanced electric technologies, and a shift away from the direct end use of coal with increasing income levels. Only under a scenario where incomes in developing regions increase slowly do global emission levels remain at close to present levels over the next century. Under a climate policy that limits emissions of carbon dioxide, sulfur dioxide emissions fall in a relatively narrow range. In most cases, the relative climatic effect of sulfur dioxide emissions decreases dramatically to a point where sulfur dioxide is only a minor component of climate forcing by the end of the century. Ecological effects of sulfur dioxide, however, could be significant in some developing regions for many decades to come.  相似文献   

2.
For the first time, based on direct observations of carbon dioxide concentration at modern Russian drifting stations, the role of the Arctic sea ice in maximum seasonal changes in carbon dioxide distribution is considered. Carbon dioxide is generated during growth of ice mass at the sea ice undersurface and is absorbed at the surface of melting sea ice. The time of ice growth is three or four times greater than that of its melting in summer months, and, as result, the time of carbon dioxide generation is longer that that of its uptake. Consequently, the Arctic Ocean is a source of carbon dioxide on the mean annual scale (the effect of Arctic “breathing”). Experiments in a freezing chamber confirm these conclusions.  相似文献   

3.
《Climate Policy》2001,1(2):155-171
Although, it has received relatively little attention as a potential method of combating climate change in comparison to energy reduction measures and development of carbon-free energy technologies, sequestration of carbon dioxide in geologic or biospheric sinks has enormous potential. This paper reviews the potential for sequestration using geological and ocean storage as a means of reducing carbon dioxide emissions.Considerable quantities of carbon dioxide separated from natural gas deposits and from hydrogen production from steam reforming of methane are already used in enhanced oil recovery and in extraction of coalbed methane, the carbon dioxide remaining sequestered at the end of the process. A number of barriers lie in the way of its implementation on a large scale. There are concerns about possible environmental effects of large-scale injection of carbon dioxide especially into the oceans. Available technologies, especially of separating and capturing the carbon dioxide from waste stream, have high costs at present, perhaps representing an additional 40–100% onto the costs of generating electricity. In most of the world there are no mechanisms to encourage firms to consider sequestration.Considerable R&D is required to bring down the costs of the process, to elucidate the environmental effects of storage and to ensure that carbon dioxide will not escape from stores in unacceptably short timescales. However, the potential of sequestration should not be underestimated as a contribution to global climate change mitigation measures.  相似文献   

4.
针对全球气候变化而引发国家间减排责任的争吵,需要各国从生产和消费的角度来认识二氧化碳排放,国家内部区域之间减排责任的分担也应该从生产和消费两个角度加以认识。为此,本文利用投入产出分析方法和EEBT(双边贸易隐含排放)核算方法核算河北省的二氧化碳排放,发现河北省生产型二氧化碳排放远大于其消费型二氧化碳排放,其中国内流出/流入引发的二氧化碳排放量较大。在利用SDA(结构分解分析法)分析影响贸易隐含二氧化碳排放变化因素时,发现行业二氧化碳排放强度变化对隐含二氧化碳排放具有积极影响,而国民经济行业之间技术经济关系的变化对隐含二氧化碳排放具有消极影响。因此,河北省在利用技术手段降低行业二氧化碳排放强度的同时,还要筛选关键性部门加以重点管理。同时,河北省贸易隐含二氧化碳排放及其影响因素变化对国家制定区域减排责任也有较强参考价值。  相似文献   

5.
Issues concerning what measures should be adopted to achieve a sustainable world with less carbon dioxide emission and in what magnitude should we reduce our emission have been on agenda in both international negotiations and countries’ policy making aimed at coping with potential global climate change. These issues cannot be easily addressed unless comprehensive understanding about the countries’ status quo as well as historical relationship between economic development and carbon dioxide emission are gained. In this paper, we examine the historical relationship between economic development and carbon dioxide emission; the ex ante restrictions on function forms and the poorly handled robustness issues rife in economics literature are synthetically addressed. Evidence from recent four decades indicates that per capita carbon dioxide emission first significantly and monotonously increase at low income level and flattens after per capita income reaches at about 22,000 $ (2005 constant price). We perform various robustness checks by employing different data sources, different model specifications and different econometric estimates. The captured development–emission relationship is robust. Our empirical results indicate factors such as urbanization, population density, trade, energy mix and economic environment impact the absolute level of carbon dioxide emission not the overall income elasticity structure of carbon dioxide emission.  相似文献   

6.
Determinations of atmospheric sulfur dioxide were made across the North American Aretic using gas chromatography with a detection limit of 25 parts per trillion by volume and a precision of 25% or better. The vertical distribution of sulfur dioxide in the Arctic atmosphere in April, 1986 was highly variable, with concentrations ranging from the detection limit to 15 parts-per-billion by volume (ppbv). While SO2 exceeded 10 ppbv in an exceptional haze layer in the Alaskan Arctic, sulfur dioxide was sometimes in the 1 – 5 ppbv range when the haze was absent. This was particularly true for the Canadian Arctic in the vicinity of Alert. In the lower stratosphere over Ellesmere Island, sulfur dioxide was 0.85 ppbv.  相似文献   

7.
The effects of doubled carbon dioxide on rainfall responses to radiative processes of water clouds are investigated in this study. The two groups of two-dimensional cloud-resolving model sensitivity experiments in pre-summer heavy rainfall around the summer solstice and tropical rainfall around the winter solstice are conducted and their averages over 5 days and model domain are analyzed. In the presence of radiative effects of ice clouds, doubled carbon dioxide changes pre-summer rainfall from the decrease associated with the enhanced atmospheric cooling to the increase associated with the enhanced infrared cooling as a result of the exclusion of radiative effects of water clouds. Doubled carbon dioxide leads to the reduction in tropical rainfall caused by the removal of radiative effects of water clouds through the suppressed infrared cooling. In the absence of radiative effects of ice clouds, doubled carbon dioxide changes pre-summer rainfall from the increase associated with the increased atmospheric warming to the decrease associated with the weakened release of latent heat caused by the elimination of radiative effects of water clouds. The exclusion of radiative effects of water clouds increases tropical rainfall through the strengthened infrared cooling, which is insensitive to the change in carbon dioxide.  相似文献   

8.
Summary Atmospheric carbon dioxide variations have been studied by using data between May 1980 and July 1989 from Sibukawa in Seto Inland Sea, sited in the western part of Japan. The power spectrum of carbon dioxide shows that the one-day period was predominant and 4 to 5 days period associated with quasiperiodic variation in weather was also significant. The seasonal variation of daily minimum concentration of carbon dioxide shows a maximum in summer months (July–September), and a minimum in winter months (November–December and January–March). The variation pattern seems to be in opposite phase to the carbon dioxide variations expected in the northern hemisphere. This was probably due to reduced vertical mixing under stable stratification of the air layer prevailing during summer months at Sibukawa station. It is noted that the air layer is in lapse conditions during winter months. The annual rate of increase of carbon dioxide concentration is examined using data obtained during winter months. It is 3.1 ppm/year. This value is about twice the increasing rate of increase on a global scale and in the lower troposphere over Japan.With 5 Figures  相似文献   

9.
The effects of doubled carbon dioxide on rainfall responses to radiative processes of water clouds are investigated in this study.Two groups of two-dimensional cloud-resolving model sensitivity experiments with regard to pre-summer heavy rainfall around the summer solstice and tropical rainfall around the winter solstice are conducted and their five-day averages over the model domain are analyzed.In the presence of radiative effects of ice clouds,doubled carbon dioxide changes pre-summer rainfall from the decrease associated with the enhanced atmospheric cooling to the increase associated with the enhanced infrared cooling as a result of the exclusion of radiative effects of water clouds.Doubled carbon dioxide leads to the reduction in tropical rainfall,caused by the removal of radiative effects of water clouds through the suppressed infrared cooling.In the absence of radiative effects of ice clouds,doubled carbon dioxide changes pre-summer rainfall from the increase associated with the strengthened atmospheric warming to the decrease associated with the weakened release of latent heat caused by the elimination of radiative effects of water clouds.The exclusion of radiative effects of water clouds increases tropical rainfall through the strengthened infrared cooling,which is insensitive to the change in carbon dioxide.  相似文献   

10.
Carbon capture and storage (CCS) is increasingly depicted as an important element of the carbon dioxide mitigation portfolio. However, critics have warned that CCS might lead to “reinforced fossil fuel lock-in”, by perpetuating a fossil fuel based energy provision system. Due to large-scale investments in CCS infrastructure, the fossil fuel based ‘regime’ would be perpetuated to at least the end of this century.In this paper we investigate if and how CCS could help to avoid reinforcing fossil fuel lock-in. First we develop a set of criteria to estimate the degree of technological lock-in. We apply these criteria to assess the lock-in reinforcement effect of adding CCS to the fossil fuel socio-technical regime (FFR).In principle, carbon dioxide could be captured from any carbon dioxide point source. In the practice of present technological innovations, business strategies, and policy developments, CCS is most often coupled to coal power plants. However, there are many point sources of carbon dioxide that are not directly related to coal or even fossil fuels. For instance, many forms of bio-energy or biomass-based processes generate significant streams of carbon dioxide emissions. Capturing this carbon dioxide which was originally sequestered in biomass could lead to negative carbon dioxide emissions.We use the functional approach of technical innovations systems (TIS) to estimate in more detail the strengths of the “niches” CCS and Bio-Energy with CCS (BECCS). We also assess the orientation of the CCS niche towards the FFR and the risk of crowding out BECCS. Next we develop pathways for developing fossil energy carbon capture and storage, BECCS, and combinations of them, using transition pathways concepts. The outcome is that a large-scale BECCS development could be feasible under certain conditions, thus largely avoiding the risk of reinforced fossil fuel lock-in.  相似文献   

11.
A calibration equation and some results of the field performance of an infrared instrument, which is designed to measure simultaneous fluctuations of atmospheric carbon dioxide and water vapor, are described. Field observations show that the instrument is suitable for simultaneous measurement of turbulent fluxes of carbon dioxide and water vapor in conjunction with a sonic anemometer. Measured values of carbon dioxide and water vapor fluxes show diurnal variations characterized by crop activity with respect to assimilation, respiration and evapotranspiration. Carbon dioxide is transferred downward during the daytime and upward at night, while latent heat and sensible heat are transferred in the opposite sense. The non-dimensional gradient of carbon dioxide is expressed in the following form under weak unstable conditions: c = (1 – 16 v )-1/2. Here, v is the Monin-Obukhov stability parameter including the humidity effect. This relation was originally proposed for temperature and humidity. Thus, the results indicate that the turbulent mechanisms of carbon dioxide fluctuations are similar to those of other scalar entities. This is strongly supported by the high correlation coefficient found between fluctuations of carbon dioxide and temperature or humidity in the air layer over crop fields.  相似文献   

12.
城市边界层动量和保守物通量的特征   总被引：2，自引：0，他引：2  
利用2005年1-5月北京325 m气象塔47 m高度的湍流脉动资料(风速、温度、水汽和CO2),对城市边界层冠层内的湍流运动统计特征(相似关系、高阶矩、通量和谱等)进行了分析。其中,谱分析的结果表明,城市冠层内稳定度对湍流谱的影响比较小,而水平风速的影响比较大。因此,速度和温度的相似关系在夜间稳定条件下也成立。但是,由于水汽和CO2还受其他因素的影响,相似关系并不适用。更高阶矩的研究表明它们的陡峭度与偏斜度之间存在平方关系。而水汽和CO2之间也存在差异,它们的通量日变化特征明显不同,CO2通量的日变化更能体现人类活动的影响。同时,感热通量、潜热通量和CO2通量存在季节变化,尤其是潜热通量季节差异很大。  相似文献   

13.
An increase in atmospheric carbon dioxide concentration has both a radiative (greenhouse) effect and a physiological effect on climate. The physiological effect forces climate as plant stomata do not open as wide under enhanced CO2 levels and this alters the surface energy balance by reducing the evapotranspiration flux to the atmosphere, a process referred to as ‘carbon dioxide physiological forcing’. Here the climate impact of the carbon dioxide physiological forcing is isolated using an ensemble of twelve 5-year experiments with the Met Office Hadley Centre HadCM3LC fully coupled atmosphere–ocean model where atmospheric carbon dioxide levels are instantaneously quadrupled and thereafter held constant. Fast responses (within a few months) to carbon dioxide physiological forcing are analyzed at a global and regional scale. Results show a strong influence of the physiological forcing on the land surface energy budget, hydrological cycle and near surface climate. For example, global precipitation rate reduces by ~3% with significant decreases over most land-regions, mainly from reductions to convective rainfall. This fast hydrological response is still evident after 5 years of model integration. Decreased evapotranspiration over land also leads to land surface warming and a drying of near surface air, both of which lead to significant reductions in near surface relative humidity (~6%) and cloud fraction (~3%). Patterns of fast responses consistently show that results are largest in the Amazon and central African forest, and to a lesser extent in the boreal and temperate forest. Carbon dioxide physiological forcing could be a source of uncertainty in many model predicted quantities, such as climate sensitivity, transient climate response and the hydrological sensitivity. These results highlight the importance of including biological components of the Earth system in climate change studies.  相似文献   

14.
We use statistical methods to analyze whether there exists long-term causality between temperature and carbon dioxide concentration. The analysis is based on a the Vostok Ice Core data from 400,000 to 6,000 years ago, extended by the EPICA Dome C data which go back to 800,000 years ago. At first, to make the data equidistant, we reconstruct it by linear interpolation. Then, using an approximation of a piecewise exponential function, we adjust for a deterministic trend. Finally, we employ the Granger causality test. We are able to strongly reject the null hypothesis that carbon dioxide concentration does not Granger cause temperature as well as the reverse hypothesis that temperature does not Granger cause carbon dioxide concentration.  相似文献   

15.
The Bowen-ratio profile method for calculating total carbon dioxide, latent heat, and sensible heat flux density above a corn crop was used by measuring temperature, water vapor, and CO2 concentrations at several heights in the aerodynamic boundary layer of the crop. The ratio (α) of sensible heat flux density to carbon dioxide flux density as well as the Bowen ratio (β) were used in the computations. The two ratios, α and β were determined graphically from the slopes of linear plots of temperature vs CO2 concentration and vs water vapor. Each of the energy flux densities was computed from the two ratios and net radiation minus soil heat flux density. An analysis of probable error was performed on the Bowen-ratio profile method to evaluate the accuracy of the flux density estimates. Less than 10% error was found for latent heat flux density and less than 15% for carbon dioxide flux density under normal midday conditions for the instrumentation used. However, the carbon dioxide flux density error increased to over 40% when the sensible heat flux was small.  相似文献   

16.
The rates and mechanisms of both gas and liquid phase reactions for the oxidation of sulfur dioxide play an important role in the production of atmospheric acids and aerosol particles. Rhodeet al. (1981) concluded that sulfate production rates were highly non-linear functions of sulfur dioxide emission rates. Their modelling study used an HO x termination mechanism for the HO—SO2 reaction in the gas-phase. Stockwell and Calvert (1983) determined that one of the products of the overall reaction of HO with sulfur dioxide was an HO2 radical. The National Research Council (1983) using a version of the Rhodeet al. (1981) model modified to include HO2 production from the HO—SO2 reaction concluded that sulfate production becomes much more linear with respect to reductions in sulfur dioxide emissions. However, the cause of this increased linearity was not explained by the National Research Council report. It is demonstrated that the increased linearity is due to the coupling of gas-phases and aqueous phase chemistry. The gas-phase sulfur dioxide oxidation mechanism has a very significant effect on hydrogen perodide production rates.  相似文献   

17.
Empirical investigations have indicated that projections of future atmospheric carbon dioxide concentrations of a quality quite adequate for practical questions regarding the environmental threat of anthropogenic carbon dioxide emissions and its relationship to energy use policy could be made with the simple assumption that a constant fraction of these emissions would be retained by the atmosphere. By analysis of the structural behavior of equations describing the transfer of carbon and carbon dioxide between their several reservoirs we have been able to demonstrate that this characteristic can be explained to result from approximately linear behavior and exponentially growing carbon dioxide release rates, combined with fitting of carbon cycle model parameters to the last twenty years of observed atmospheric carbon dioxide growth. These conclusions are independent of the details of carbon cycle model structure for projections up to 100 years into the future as long as the growth in atmospheric carbon dioxide release rates is sufficiently high, of the order of 1.5% per annum or more, as referenced to p re-industrial (steady state) conditions. At low rates of growth, when the longer response times of the carbon cycling system become important, for most energy use projections the resultant CO2 induced climate changes are small and the uncertainties in predicted atmospheric carbon dioxide level are thus not important. A possible exception to this condition occurs for scenarios of future fossil fuel use rates designed to avoid atmospheric CO2 levels exceeding a chosen threshold. In this instance details of carbon cycle model structure could significantly affect conclusions that might be drawn concerning future energy use policies; however, it is possible that such a result stems from inappropriate specification of a criterion for an environmental threat, rather than from inherent inadequacy of current carbon cycle models. Recent carbon cycle model developments postulate transfer processes of carbon into the deep ocean, large carbon storage reservoir at rates much higher than in the models we have analysed. If the existence of such mechanisms is confirmed, and they are found to be sufficiently rapid and large, some of our conclusions regarding the use of the constant fractional retention assumption may have to be modified. Currently at the Gas Research Institute, 8600 West Bryn, Mawr Ave., Chicago, IL 60631, U.S.A.  相似文献   

18.
The ongoing human-induced emission of carbon dioxide (CO2) threatens to change the earth's climate. One possible way of decreasing CO2 emissions is to apply CO2 removal, which involves recovering of carbon dioxide from energy conversion processes and storing it outside the atmosphere. Since the 1980's, the possibilities for recovering CO2 from thermal power plants received increasing attention.In this study possible techniques of recovering CO2 from large-scale industrial processes are assessed.In some industrial processes, e.g. ammonia production, CO2 is recovered from the process streams to prevent it from interfering with the production process. The CO2 thus recovered can easily be dehydrated and compressed, at low cost. In the iron and steel industry, carbon dioxide can be recovered from blast furnace gas. In the petrochemical industry CO2 can be recovered from flue gases, using low-temperature heat for the separation process.Carbon dioxide can be recovered from large-scale industrial processes and in some cases the cost of recovery is significantly less than CO2 recovery from thermal power plants. Therefore this option should be studied further and should be considered if carbon dioxide removal is introduced on a wide scale.  相似文献   

19.
ABSTRACT Rainfall responses to doubled atmospheric carbon dioxide concentration were investigated through the analysis of two pairs of two-dimensional cloud-resolving model sensitivity experiments. One pair of experiments simulated pre-summer heavy rainfall over southern China around the summer solstice, whereas the other pair of experiments simulated tropical rainfall around the winter solstice. The analysis of the time and model domain mean heat budget revealed that the enhanced local atmospheric warming was associated with doubled carbon dioxide through the weakened infrared radiative cooling during the summer solstice. The weakened mean pre-summer rainfall corresponded to the weakened mean infrared radiative cooling. Doubled carbon dioxide increased the mean tropical atmospheric warming via the enhanced mean latent heat in correspondence with the strengthened mean infrared radiative cooling during the winter solstice. The enhanced mean tropical rainfall was associated with the increased mean latent heat.  相似文献   

20.
The buildup of carbon dioxide in the global atmosphere represents one of the principal causes of the greenhouse effect that is overtaking the Earth's climatic systems and that threatens salient sectors of economic development in both the developed and developing worlds. A management response appears to offer substantial scope to counter the buildup of carbon dioxide, even though it has been little addressed in systematic fashion. It is a massive tree-planting programme in the humid tropics. Tree plantations absorb carbon dioxide from the atmosphere, and the humid tropics with year-round warmth and moisture are by far the best place for fast-growing tree plantations. Reforestation on a suitable scale in the humid tropics - accompanied of course by measures to halt deforestation - could eventually serve to sequester carbon in amounts significant for our efforts to counter the greenhouse effect.  相似文献   

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