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1.
We have compiled historical greenhouse gas emissions and their uncertainties on country and sector level and assessed their contribution to cumulative emissions and to global average temperature increase in the past and for a the future emission scenario. We find that uncertainty in historical contribution estimates differs between countries due to different shares of greenhouse gases and time development of emissions. Although historical emissions in the distant past are very uncertain, their influence on countries?? or sectors?? contributions to temperature increase is relatively small in most cases, because these results are dominated by recent (high) emissions. For relative contributions to cumulative emissions and temperature rise, the uncertainty introduced by unknown historical emissions is larger than the uncertainty introduced by the use of different climate models. The choice of different parameters in the calculation of relative contributions is most relevant for countries that are different from the world average in greenhouse gas mix and timing of emissions. The choice of the indicator (cumulative GWP weighted emissions or temperature increase) is very important for a few countries (altering contributions up to a factor of 2) and could be considered small for most countries (in the order of 10%). The choice of the year, from which to start accounting for emissions (e.g. 1750 or 1990), is important for many countries, up to a factor of 2.2 and on average of around 1.3. Including or excluding land-use change and forestry or non-CO2 gases changes relative contributions dramatically for a third of the countries (by a factor of 5 to a factor of 90). Industrialised countries started to increase CO2 emissions from energy use much earlier. Developing countries?? emissions from land-use change and forestry as well as of CH4 and N2O were substantial before their emissions from energy use.  相似文献   

2.
In the context of recent discussions at the UN climate negotiations we compared several ways of calculating historical greenhouse gas (GHG) emissions, and assessed the effect of these different approaches on countries’ relative contributions to cumulative global emissions. Elements not covered before are: (i) including recent historical emissions (2000–2010), (ii) discounting historical emissions to account for technological progress; (iii) deducting emissions for ‘basic needs’; (iv) including projected emissions up to 2020, based on countries’ unconditional reduction proposals for 2020. Our analysis shows that countries’ contributions vary significantly based on the choices made in the calculation: e.g. the relative contribution of developed countries as a group can be as high as 80 % when excluding recent emissions, non-CO2 GHGs, and land-use change and forestry CO2; or about 48 % when including all these emissions and discounting historical emissions for technological progress. Excluding non-CO2 GHGs and land-use change and forestry CO2 significantly changes relative historical contributions for many countries, altering countries’ relative contributions by multiplicative factors ranging from 0.15 to 1.5 compared to reference values (i.e. reference contribution calculations cover the period 1850-2010 and all GHG emissions). Excluding 2000–2010 emissions decreases the contributions of most emerging economies (factor of up to 0.8). Discounting historical emissions for technological progress reduces the relative contributions of some developed countries (factor of 0.8) and increases those of some developing countries (factor of 1.2–1.5). Deducting emissions for ‘basic needs’ results in smaller contributions for countries with low per capita emissions (factor of 0.3–0.5). Finally, including projected emissions up to 2020 further increases the relative contributions of emerging economies by a factor of 1.2, or 1.5 when discounting pre-2020 emissions for technological progress.  相似文献   

3.
This paper discusses methodological issues relevant to the calculation of historical responsibility of countries for climate change (‘The Brazilian Proposal’). Using a simple representation of the climate system, the paper compares contributions to climate change using different indicators: current radiative forcing, current GWP-weighted emissions, radiative forcing from increased concentrations, cumulative GWP-weighted emissions, global-average surface-air temperature increase and two new indicators: weighted concentrations (analogue to GWP-weighted emissions) and integrated temperature increase. Only the last two indicators are at the same time ‘backward looking’ (take into account historical emissions), ‘backward discounting’ (early emissions weigh less, depending on the decay in the atmosphere) and ‘forward looking’ (future effects of the emissions are considered) and are comparable for all gases. Cumulative GWP-weighted emissions are simple to calculate but are not ‘backward discounting’. ‘Radiative forcing’ and ‘temperature increase’ are not ‘forward looking’. ‘Temperature increase’ discounts the emissions of the last decade due to the slow response of the climate system. It therefore gives low weight to regions that have recently significantly increased emissions. Results of the five different indicators are quite similar for large groups (but possibly not for individual countries): industrialized countries contributed around 60% to today’s climate change, developing countries around 40% (using the available data for fossil, industrial and forestry CO2, CH4 and N2O). The paper further argues including non-linearities of the climate system or using a simplified linear system is a political choice. The paper also notes that results of contributions to climate change need to be interpreted with care: Countries that developed early benefited economically, but have high historical emission, and countries developing at a later period can profit from developments in other countries and are therefore likely to have a lower contribution to climate change.  相似文献   

4.
Emission scenarios and global climate protection   总被引：1，自引：0，他引：1  
This paper evaluates the effectiveness of a wide range of emission scenarios in protecting climate (where ‘protecting climate’ Is used here to mean minimizing ‘dangerous anthropogenic interference with the climate system’ which results in impacts to society and the natural environment). Under baseline (no action) conditions there is a significant Increase in emissions, temperature and climate impacts. Controlling only CO2 emissions (ie freezing emissions in year 2000 at 1990 levels, and decreasing them afterwards at 1%/yr) and only in Annex I countries, does not significantly reduce the impacts observed under the baseline scenario. However, impacts are substantially reduced when emissions are controlled in both Annex I and non-Annex I countries, and when both CO2 and non-CO2 emissions are controlled. It was also found that stabilizing CO2 in the atmosphere below 450 ppm substantially reduces climate impacts. But in order to follow the pathway to stabilization at 450 ppm specified by the IPCC, global emissions can only slightly increase in the coming decades, and then must be sharply reduced. On the other hand, stabilizing CO2 in the atmosphere above 450 ppm can have significant impacts, which indicates that stabilization of greenhouse gases in the atmosphere will not necessarily provide a high level of climate protection. Results from these and other scenarios are synthesized and related to climate protection goals through a new concept — ‘safe emission corridors’. These corridors indicate the allowable range of near-term global emissions (equivalent CO2) which complies with specified short- and long-term climate goals. For an illustrative set of climate goals, the allowable anthropogenic global emissions in 2010 are computed to range from 7.3 to 14.5 GtC/yr equivalent CO2 (1990 level = approximately 9.6 GtC/ yr); when these limits are set twice as strict (ie divided by two), the allowable range becomes 7.6 to 9.3 GtC/yr. To fall within this lower corridor, global emissions must be lower in 2010 than in 1990.  相似文献   

5.
We present and apply a simple bottom–up model for estimating non-energy use of fossil fuels and resulting CO2 (carbon dioxide) emissions. We apply this model for the year 2000: (1) to the world as a whole, (2) to the aggregate of Annex I countries and non-Annex I countries, and (3) to the ten non-Annex I countries with the highest consumption of fossil fuels for non-energy purposes. We find that worldwide non-energy use is equivalent to 1,670 ± 120 Mt (megatonnes) CO2 and leads to 700 ± 90 Mt CO2 emissions. Around 75% of non-energy use emissions is related to industrial processes. The remainder is attributed to the emission source categories of solvent and other product use, agriculture, and waste. Annex I countries account for 51% (360 ± 50 Mt CO2) and non-Annex I countries for 49% (340 ± 70 Mt CO2) of worldwide non-energy use emissions. Among non-Annex I countries, China is by far the largest emitter of non-energy use emissions (122 ± 18 Mt CO2). Our research deepens the understanding of non-energy use and related CO2 emissions in countries for which detailed emission inventories do not yet exist. Despite existing model uncertainties, we recommend NEAT-SIMP to inventory experts for preparing correct and complete non-energy use emission estimates for any country in the world.  相似文献   

6.
The IPCC Fourth Assessment Report, Working Group III, summarises in Box 13.7 the required emission reduction ranges in Annex I and non-Annex I countries as a group, to achieve greenhouse gas concentration stabilisation levels between 450 and 650 ppm CO2-eq. The box summarises the results of the IPCC authors’ analysis of the literature on the regional allocation of the emission reductions. The box states that Annex I countries as a group would need to reduce their emissions to below 1990 levels in 2020 by 25% to 40% for 450 ppm, 10% to 30% for 550 ppm and 0% to 25% for 650 ppm CO2-eq, even if emissions in developing countries deviate substantially from baseline for the low concentration target. In this paper, the IPCC authors of Box 13.7 provide background information and analyse whether new information, obtained after completion of the IPCC report, influences these ranges. The authors concluded that there is no argument for updating the ranges in Box 13.7. The allocation studies, which were published after the writing of the IPCC report, show reductions in line with the reduction ranges in the box. From the studies analysed, this paper specifies the “substantial deviation” or “deviation from baseline” in the box: emissions of non-Annex I countries as a group have to be below the baseline roughly between 15% to 30% for 450 ppm CO2-eq, 0% to 20% for 550 ppm CO2-eq and from 10% above to 10% below the baseline for 650 ppm CO2-eq, in 2020. These ranges apply to the whole group of non-Annex I countries and may differ substantially per country. The most important factor influencing these ranges above, for non-Annex I countries, and in the box, for Annex I countries, is new information on higher baseline emissions (e.g. that of Sheehan, Climatic Change, 2008, this issue). Other factors are the assumed global emission level in 2020 and assumptions on land-use change and forestry emissions. The current, slow pace in climate policy and the steady increase in global emissions, make it almost unfeasible to reach relatively low global emission levels in 2020 needed to meet 450 ppm CO2-eq, as was first assumed feasible by some studies, 5 years ago.  相似文献   

7.
The greenhouse gases emission (CO2, CH4, and N2O) from domestic and international aviation in the Russian Federation is assessed. In 2007, the total emission of CO2, CH4, and N2O amounted to 18.4 million tons of CO2-equivalent, which is 21% below the 1990 level. Carbon dioxide dominates in the component composition of the emissions, its part in 2007 accounted for 99.1% of the emission. Taking into account the tendency towards increasing fuel consumption due to intense aircraft traffic it can be expected that compared to the present level the greenhouse gases emissions in 2012 and 2020 will increase by 15 and 45%, respectively. Accounting for the increased aircraft emissions as well as plans of foreign countries to include the international aviation into the scheme of greenhouse gases emission allowance (trade credits) it is expedient to make more precise the greenhouse gases emissions from the Russian aviation based on the detailed flight data for all types of the aircraft.  相似文献   

8.
Abstract

This article presents a set of multi-gas emission pathways for different CO2-equivalent concentration stabilization levels, i.e. 400, 450, 500 and 550 ppm CO2-equivalent, along with an analysis of their global and regional reduction implications and implied probability of achieving the EU climate target of 2°C. For achieving the 2°C target with a probability of more than 60%, greenhouse gas concentrations need to be stabilized at 450 ppm CO2-equivalent or below, if the 90% uncertainty range for climate sensitivity is believed to be 1.5–4.5°C. A stabilization at 450 ppm CO2-equivalent or below (400 ppm) requires global emissions to peak around 2015, followed by substantial overall reductions of as much as 25% (45% for 400 ppm) compared to 1990 levels in 2050. In 2020, Annex I emissions need to be approximately 15% (30%) below 1990 levels, and non-Annex I emissions also need to be reduced by 15–20% compared to their baseline emissions. A further delay in peaking of global emissions by 10 years doubles maximum reduction rates to about 5% per year, and very probably leads to high costs. In order to keep the option open of stabilizing at 400 and 450 ppm CO2-equivalent, the USA and major advanced non-Annex I countries will have to participate in the reductions within the next 10–15 years.  相似文献   

9.
This paper is Part II of a two-part series in which the risks associated with unrestrained greenhouse-gas emissions, and with measures to limit emissions, are reviewed. A sustained limitation of global CO2 emissions requires global population stabilization, a reduction in per capita emissions in the developed world, and a limitation of the increase in per capita emissions in the developing world. Reducing or limiting per capita emissions requires a major effort to improve the efficiency with which energy is transformed and used; urban development which minimizes the need for the private automobile and facilitates district heating, cooling, and cogeneration systems; and accelerated development of renewable energy. The following risks associated with these efforts to limit CO2 emissions are reviewed here: (i) resources might be diverted from other urgent needs; (ii) economic growth might be reduced; (iii) reduction measures might cost more than expected; (iv) early action might cost more than later action; (v) reduction measures might have undesired side effects; (vi) reduction measures might require heavy-handed government intervention; and (vii) reduction measures might not work. With gradual implementation of a diversified portfolio of measures, these risks can be greatly reduced. Net risk is further reduced by the fact that a number of non-climatic benefits would result from measures to limit CO2 emissions. Based on the review of risks associated with measures to limit emissions here, and the review of the risks associated with unrestrained emissions presented in Part I, it is concluded that a reasonable near-term (20–30 year) risk hedging strategy is one which seeks to stabilize global fossil CO2 emissions at the present (early 1990's) level. This in turn implies an emission reduction of 26% for industrialized countries as a whole and 40–50% for Canada and the USA if developing country emissions are to increase by no more than 60%, which in itself would require major assistance from the industrialized countries. The effectiveness of global CO2-emission stabilization in slowing down the buildup of atmospheric CO2 is enhanced by the fact that the airborne fraction (ratio of annual atmospheric CO2 increase to total annual anthropogenic emissions) decreases if emissions are stabilized, whereas it increases if emissions continue to grow exponentially. The framework and conclusions presented here are critically compared with so-called optimization frameworks.  相似文献   

10.
In this paper we quantify the CH4, CO2 and NO x emissions during routine operations at a major oil and gas production facility, Prudhoe Bay, Alaska, using the concentrations of combustion by products measured at the NOAA-CMDL observatory at Barrow, Alaska and fuel consumption data from Prudhoe Bay. During the 1989 and 1990 measurement campaigns, 10 periods (called events) were unambiguously identified where surface winds carry the Prudhoe Bay emissions to Barrow (approximately 300 km). The events ranged in duration from 8–48 h and bring ambient air masses containing substantially elevated concentrations of CH4, CO2 and NO y to Barrow. Using the slope of the observed CH4 vs CO2 concentrations during the events and the CO2 emissions based on reported fuel consumption data, we calculate annual CH4 emissions of (24+/–8)×103 metric tons from the facility. In a similar manner, the annual NO x emissions are calculated to be (12+/–4)×103 metric tons, which is in agreement with an independently determined value. The calculated CH4 emissions represent the amount released during routine operations including leakage. However this quantity would not include CH4 released during non-routine operations, such as from venting or gas flaring.  相似文献   

11.
To mitigate the effects of climate change, countries worldwide are advancing technologies to reduce greenhouse gas emissions. This paper proposes and measures optimal production resource reallocation using data envelopment analysis. This research attempts to clarify the effect of optimal production resource reallocation on CO2 emissions reduction, focusing on regional and industrial characteristics. We use finance, energy, and CO2 emissions data from 13 industrial sectors in 39 countries from 1995 to 2009. The resulting emissions reduction potential is 2.54 Gt-CO2 in the year 2009, with former communist countries having the largest potential to reduce CO2 emissions in the manufacturing sectors. In particular, basic material industry including chemical and steel sectors has a lot of potential to reduce CO2 emissions.  相似文献   

12.
Individual countries are requested to submit nationally determined contributions(NDCs) to alleviate global warming in the Paris Agreement. However, the global climate effects and regional contributions are not explicitly considered in the countries’ decision-making process. In this study, we evaluate the global temperature slowdown of the NDC scenario(?T =0.6°C) and attribute the global temperature slowdown to certain regions of the world with a compact earth system model.Considering reductions ...  相似文献   

13.
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.  相似文献   

14.
The drivers of Chinese CO2 emissions from 1980 to 2030   总被引：4，自引：0，他引：4  
China's energy consumption doubled within the first 25 years of economic reforms initiated at the end of the 1970s, and doubled again in the past 5 years. It has resulted of a threefold CO2 emissions increase since early of 1980s. China's heavy reliance on coal will make it the largest emitter of CO2 in the world. By combining structural decomposition and input–output analysis we seek to assess the driving forces of China's CO2 emissions from 1980 to 2030. In our reference scenario, production-related CO2 emissions will increase another three times by 2030. Household consumption, capital investment and growth in exports will largely drive the increase in CO2 emissions. Efficiency gains will be partially offset the projected increases in consumption, but our scenarios show that this will not be sufficient if China's consumption patterns converge to current US levels. Relying on efficiency improvements alone will not stabilize China's future emissions. Our scenarios show that even extremely optimistic assumptions of widespread installation of carbon dioxide capture and storage will only slow the increase in CO2 emissions.  相似文献   

15.
The greenhouse gas emissions scenarios published by the IPCC in the Special Report on Emission Scenarios (SRES) continue to serve as a primary basis for assessing future climate change and possible response strategies. These scenarios were developed between 1996 and 1999 and sufficient time has now passed to make it worth examining their consistency with more recent data and projections. The comparison performed in this paper includes population, GDP, energy use, and emissions of CO2, non-CO2 gases and sulfur. We find the SRES scenarios to be largely consistent with historical data for the 1990–2000 period and with recent projections. Exceptions to this general observation include (1) in the long-term, relatively high population growth assumptions; in some regions, particularly in the A2 scenario; (2) in the medium-term, relatively high economic growth assumptions in the LAM (Latin America, Africa and Middle East) region in the A1 scenario; (3) in the short-term, CO2 emissions projections in A1 that are somewhat higher than the range of current scenarios; and (4) substantially higher sulfur emissions in some scenarios than in historical data and recent projections. In conclusion, given the relatively small inconsistencies for use as global scenarios there seems to be no immediate need for a large-scale IPCC-led update of the SRES scenarios that is solely based on the SRES scenario performance vis-a-vis data for the 1990–2000 period and/or more recent projections. Based on reported findings, individual research teams could make, and in some cases already have made, useful updates of the scenarios.  相似文献   

16.
A core question still remains after the Paris Agreement: who receives how much of the remaining CO2 budget (resource/burden/effort sharing), so that the increase in the global average temperature is kept to well below 2°C above pre-industrial levels? If converging per capita emissions serve as a possible answer to this question, the discussion focuses primarily on the approach ‘Contraction and Convergence’ (C&C). The Regensburg Model now offers a further option for the mathematical implementation of converging per capita emissions. The authors identify features common to C&C and differences from C&C. They show that, of the convergence models they examined, the Regensburg Model is the most favourable option for industrialized countries.

Policy relevance

In politics, the concept of converging per capita emissions is often accepted at the abstract level. Civil society in particular can then take politicians at their word wherever they take values calculated using the Regensburg Model as points of reference; then prosperous developed countries in particular whose nationally determined contributions do not come up even to these reference values will find it difficult to justify their contributions.  相似文献   

17.
《Climate Policy》2013,13(6):569-576
In contrast to many discussions based on annual emissions, this article presents calculations and projections of cumulative contributions to the stock of atmospheric CO2 by the major players, China, Europe, India, Japan and the USA, for the period 1900–2080. Although relative contributions to the climate problem are changing dramatically, notably due to the rapid industrialization of China, long-term responsibilities for enhanced global warming have not been transparently quantified in the literature. The analysis shows that if current trends continue, by the middle of this century China will overtake the USA as the major cumulative contributor to atmospheric concentrations of CO2. This has enormous implications for the debate on the ethical responsibilities of the major greenhouse gas emitters. Effective climate policy will require both the recognition of shared responsibility and an unprecedented degree of cooperation.  相似文献   

18.
Since 1970, global agricultural production has more than doubled with agriculture and land-use change now responsible for ∼1/4 of greenhouse gas emissions from human activities. Yet, while greenhouse gas (GHG) emissions per unit of agricultural product have been reduced at a global level, trends in world regions have been quantified less thoroughly. The KPI (Kaya-Porter Identity) is a novel framework for analysing trends in agricultural production and land-use change and related GHG emissions. We apply this to assess trends and differences in nine world regions over the period 1970–2007. We use a deconstructed analysis of emissions from the mix of multiple sources, and show how each is changing in terms of absolute emissions on a per area and per produced unit basis, and how the change of emissions from each source contributes to the change in total emissions over time. The doubling of global agricultural production has mainly been delivered by developing and transitional countries, and this has been mirrored by increased GHG emissions. The decoupling of emissions from production shows vast regional differences. Our estimates show that emissions per unit crop (as kg CO2-equivalents per Giga Joule crop product), in Oceania, have been reduced by 94% from 1093 to 69; in Central & South America by 57% from 849 to 362; in sub-Saharan Africa by 27% from 421 to 309, and in Europe by 56% from 86 to 38. Emissions per unit livestock (as kg CO2-eq. GJ−1 livestock product) have reduced; in sub-Saharan Africa by 24% from 6001 to 4580; in Central & South America by 61% from 3742 to 1448; in Central & Eastern Asia by 82% from 3,205 to 591, and; in North America by 28% from 878 to 632. In general, intensive and industrialised systems show the lowest emissions per unit of agricultural production.  相似文献   

19.
This study provides estimates of greenhouse gas emissions from the major anthropogenic sources for 142 countries. The data compilation is comprehensive in approach, including emissions from CO, CH4, and N2O, and ten halocarbons, in addition to CO2. The sources include emissions from fossil fuel production and use, cement production, halocarbons, landfills, land use changes, biomass burning, rice and livestock production and fertilizer consumption. The approach used to derive these estimates corresponds closely with the simple methodologies proposed by the Greenhouse Gas Emissions Task Force of the Intergovernmental Panel on Climate Change. The inventory includes a new estimate of greenhouse gas emissions from fossil fuel combustion based principally on data from the International Energy Agency. The research methodologies for estimating emissions from all sources is briefly described and compared with other recent studies in the literature.  相似文献   

20.
The purpose of this paper is to describe global urban greenhouse gas emissions by region and sector, examine the distribution of emissions through the urban-to-rural gradient, and identify covariates of emission levels for our baseline year, 2000. We use multiple existing spatial databases to identify urban extent, greenhouse gas emissions (CO2, N2O, CH4 and SF6) and covariates of emissions in a “top-down” analysis. The results indicate that urban activities are significant sources of total greenhouse gas emissions (36.8 and 48.6 % of total). The urban energy sector accounts for between 41.5 and 66.3 % of total energy emissions. Significant differences exist in the urban share of greenhouse gas emissions between developed and developing countries as well as among source sectors for geographic regions. The 50 largest urban emitting areas account for 38.8 % of all urban greenhouse gas emissions. We find that greenhouse gas emissions are significantly associated with population size, density, growth rates, and per capita income. Finally, comparison of our results to “bottom-up” estimates suggest that this research’s data and techniques are best used at the regional and global scales.  相似文献   

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