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1.
Roy Darwin 《Climatic change》2004,66(1-2):191-238
Because of many uncertainties, quantitative estimates of agriculturally related economic impacts of greenhouse gas emissions are often given low confidence. A major source of uncertainty is our inability to accurately project future changes in economic activity, emissions, and climate. This paper focuses on two issues. First, to what extent do variable projections of climate generate uncertainty in agriculturally related economic impacts? Second, to what extent do agriculturally related economic impacts of greenhouse gas emissions depend on economic conditions at the time of impacts? Results indicate that uncertainty due to variable projections of climate is fairly large for most of the economic effects evaluated in this analysis. Results also indicate that economic conditions at the time of impact influence the direction and size of as well as the confidence in the economic effects of identical projections of greenhouse gas impacts. The economic variable that behaves most consistently in this analysis is world crop production. Increases in mean global temperature, for example, cause world crop production to decrease on average under both 1990 and improved economic conditions and in both instances the confidence with respect to variable projections of climate is medium (e.g.,67%) or greater. In addition and as expected, CO2 fertilization causesworld crop production to increase on average under 1990 and improved economic conditions. These results suggest that crop production may be a fairly robust indicator of the potential impacts of greenhouse gas emissions.A somewhat unexpected finding is that improved economic conditions are not necessarily a panacea to potential greenhouse-gas-induced damages, particularly at the region level. In fact, in some regions, impacts of climate change or CO2 fertilization that are beneficial undercurrent economic conditions may be detrimental under improved economic conditions (relative to the new economic base). Australia plus New Zealand suffer from this effect in this analysis because under improved economic conditions they are assumed to obtain a relatively large share of income from agricultural exports. When the climate-change and CO2-fertilization scenariosin this analysis are also included, agricultural exports from Australia plus New Zealand decline on average. The resultant declines in agricultural income in Australia plus New Zealand are too large to be completely offset by rising incomes in other sectors. This indicates that regions that rely on agricultural exports for relatively large shares of their income may be vulnerable not only to direct climate-induced agricultural damages, but also to positive impacts induced by greenhouse gas emissions elsewhere. 相似文献
2.
3.
Contributions of individual countries?? emissions to climate change and their uncertainty 总被引：1，自引：0，他引：1
Niklas H?hne Helcio Blum Jan Fuglestvedt Ragnhild Bieltvedt Skeie Atsushi Kurosawa Guoquan Hu Jason Lowe Laila Gohar Ben Matthews Ana Claudia Nioac de Salles Christian Ellermann 《Climatic change》2011,106(3):359-391
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
4.
Comparison of uncertainty sources for climate change impacts: flood frequency in England 总被引：6，自引：3，他引：3
This paper investigates the uncertainty in the impact of climate change on flood frequency in England, through the use of continuous simulation of river flows. Six different sources of uncertainty are discussed: future greenhouse gas emissions; Global Climate Model (GCM) structure; downscaling from GCMs (including Regional Climate Model structure); hydrological model structure; hydrological model parameters and the internal variability of the climate system (sampled by applying different GCM initial conditions). These sources of uncertainty are demonstrated (separately) for two example catchments in England, by propagation through to flood frequency impact. The results suggest that uncertainty from GCM structure is by far the largest source of uncertainty. However, this is due to the extremely large increases in winter rainfall predicted by one of the five GCMs used. Other sources of uncertainty become more significant if the results from this GCM are omitted, although uncertainty from sources relating to modelling of the future climate is generally still larger than that relating to emissions or hydrological modelling. It is also shown that understanding current and future natural variability is critical in assessing the importance of climate change impacts on hydrology. 相似文献
5.
Understanding public complacency about climate change: adults’ mental models of climate change violate conservation of matter 总被引：1，自引：2，他引：1
Public attitudes about climate change reveal a contradiction. Surveys show most Americans believe climate change poses serious
risks but also that reductions in greenhouse gas (GHG) emissions sufficient to stabilize atmospheric GHG concentrations can
be deferred until there is greater evidence that climate change is harmful. US policymakers likewise argue it is prudent to
wait and see whether climate change will cause substantial economic harm before undertaking policies to reduce emissions.
Such wait-and-see policies erroneously presume climate change can be reversed quickly should harm become evident, underestimating
substantial delays in the climate’s response to anthropogenic forcing. We report experiments with highly educated adults –
graduate students at MIT – showing widespread misunderstanding of the fundamental stock and flow relationships, including
mass balance principles, that lead to long response delays. GHG emissions are now about twice the rate of GHG removal from
the atmosphere. GHG concentrations will therefore continue to rise even if emissions fall, stabilizing only when emissions
equal removal. In contrast, most subjects believe atmospheric GHG concentrations can be stabilized while emissions into the
atmosphere continuously exceed the removal of GHGs from it. These beliefs – analogous to arguing a bathtub filled faster than
it drains will never overflow – support wait-and-see policies but violate conservation of matter. Low public support for mitigation
policies may arise from misconceptions of climate dynamics rather than high discount rates or uncertainty about the impact
of climate change. Implications for education and communication between scientists and nonscientists (the public and policymakers)
are discussed. 相似文献
6.
Developing economy greenhouse gas emissions are growing rapidly relative to developed economy emissions (Boden et al. 2010) and developing economies as a group have greater emissions than developed economies. These developments are expected to continue (U.S. Energy Information Administration 2010), which has led some to question the effectiveness of emissions mitigation in developed economies without a commitment to extensive mitigation action from developing economies. One often heard argument against proposed U.S. legislation to limit carbon emissions to mitigate climate change is that, without participation from large developing economies like China and India, stabilizing temperature at 2 degrees Celsius above preindustrial (United Nations 2009), or even reducing global emissions levels, would be impossible (Driessen 2009; RPC Energy Facts 2009) or prohibitively expensive (Clarke et al. 2009). Here we show that significantly delayed action by rapidly developing countries is not a reason to forgo mitigation efforts in developed economies. This letter examines the effect of a scenario with no explicit international climate policy and two policy scenarios, full global action and a developing economy delay, on the probability of exceeding various global average temperature changes by 2100. This letter demonstrates that even when developing economies delay any mitigation efforts until 2050 the effect of action by developed economies will appreciably reduce the probability of more extreme levels of temperature change. This paper concludes that early carbon mitigation efforts by developed economies will considerably affect the distribution over future climate change, whether or not developing countries begin mitigation efforts in the near term. 相似文献
7.
Stephan Lewandowsky James S. Risbey Michael Smithson Ben R. Newell John Hunter 《Climatic change》2014,124(1-2):21-37
Uncertainty forms an integral part of climate science, and it is often used to argue against mitigative action. This article presents an analysis of uncertainty in climate sensitivity that is robust to a range of assumptions. We show that increasing uncertainty is necessarily associated with greater expected damages from warming, provided the function relating warming to damages is convex. This constraint is unaffected by subjective or cultural risk-perception factors, it is unlikely to be overcome by the discount rate, and it is independent of the presumed magnitude of climate sensitivity. The analysis also extends to “second-order” uncertainty; that is, situations in which experts disagree. Greater disagreement among experts increases the likelihood that the risk of exceeding a global temperature threshold is greater. Likewise, increasing uncertainty requires increasingly greater protective measures against sea level rise. This constraint derives directly from the statistical properties of extreme values. We conclude that any appeal to uncertainty compels a stronger, rather than weaker, concern about unabated warming than in the absence of uncertainty. 相似文献
8.
Public engagement with carbon and climate change: To what extent is the public ‘carbon capable’? 总被引：1，自引：0，他引：1
The relevance of climate change for society seems indisputable: scientific evidence points to a significant human contribution in causing climate change, and impacts which will increasingly affect human welfare. In order to meet national and international greenhouse gas (GHG) emissions reduction targets, there is an urgent need to understand and enable societal engagement in mitigation. Yet recent research indicates that this involvement is currently limited: although awareness of climate change is widespread, understanding and behavioral engagement are far lower. Proposals for mitigative ‘personal carbon budgets’ imply a need for public understanding of the causes and consequences of carbon emissions, as well as the ability to reduce emissions. However, little has been done to consider the situated meanings of carbon and energy in everyday life and decisions. This paper builds on the concept of ‘carbon capability’, a term which captures the contextual meanings associated with carbon and individuals’ abilities and motivations to reduce emissions. We present empirical findings from a UK survey of public engagement with climate change and carbon capability, focusing on both individual and institutional dimensions. These findings highlight the diverse public understandings about ‘carbon’, encompassing technical, social, and moral discourses; and provide further evidence for the environmental value-action gap in relation to adoption of low-carbon lifestyles. Implications of these findings for promoting public engagement with climate change and carbon capability are discussed. 相似文献
9.
The recent change in US presidential administrations has introduced significant uncertainty about both domestic and international policy support for continued reductions in GHG emissions. This brief analysis estimates the potential climate ramifications of changing US leadership, contrasting the Mid-Century Strategy for Deep Decarbonization (MCS) released under the Obama Administration, with campaign statements, early executive actions, and prevailing market conditions to estimate potential emission pathways under the Trump Administration. The analysis highlights areas where GHG reductions are less robust to changing policy conditions, and offers brief recommendations for addressing emissions in the interim. It specifically finds that continued reductions in the electricity sector are less vulnerable to changes in federal policy than those in the built environment and land use sectors. Given the long-lived nature of investments in these latter two sectors, however, opportunities for near-term climate action by willing cities, states, private landowners, and non-profit organizations warrant renewed attention in this time of climate uncertainty.Key policy insights
The recent US presidential election has already impacted mitigation goals and practices, injecting considerable uncertainty into domestic and international efforts to address climate change.
A strategic assessment issued in the final days of the Obama Administration for how to reach long-term climate mitigation objectives provides a baseline from which to gauge potential changes under the Trump Administration.
Though market trends may continue to foster emission declines in the energy sector, emission reductions in the land use sector and the built environment are subject to considerable uncertainty.
Regardless of actions to scale back climate mitigation efforts, US emissions are likely to be flat in the coming years. Assuming that emissions remain constant under President Trump and that reductions resume afterwards to meet the Obama Administration mid-century targets in 2050, this near-term pause in reductions yields a difference in total emissions equivalent to 0.3–0.6 years of additional global greenhouse gas emissions, depending on the number of terms served by a Trump Administration.
10.
Impact of climate change on Pacific Northwest hydropower 总被引：2，自引：0，他引：2
The Pacific Northwest (PNW) hydropower resource, central to the region’s electricity supply, is vulnerable to the impacts
of climate change. The Northwest Power and Conservation Council (NWPCC), an interstate compact agency, has conducted long
term planning for the PNW electricity supply for its 2005 Power Plan. In formulating its power portfolio recommendation, the
NWPCC explored uncertainty in variables that affect the availability and cost of electricity over the next 20 years. The NWPCC
conducted an initial assessment of potential impacts of climate change on the hydropower system, but these results are not
incorporated in the risk model upon which the 2005 Plan recommendations are based. To assist in bringing climate information
into the planning process, we present an assessment of uncertainty in future PNW hydropower generation potential based on
a comprehensive set of climate models and greenhouse gas emissions pathways. We find that the prognosis for PNW hydropower
supply under climate change is worse than anticipated by the NWPCC’s assessment. Differences between the predictions of individual
climate models are found to contribute more to overall uncertainty than do divergent emissions pathways. Uncertainty in predictions
of precipitation change appears to be more important with respect to impact on PNW hydropower than uncertainty in predictions
of temperature change. We also find that a simple regression model captures nearly all of the response of a sequence of complex
numerical models to large scale changes in climate. This result offers the possibility of streamlining both top-down impact
assessment and bottom-up adaptation planning for PNW water and energy resources. 相似文献
11.
Increasing greenhouse gas emissions are projected to raise global average surface temperatures by 3?–4 °C within this century, dramatically increasing the extinction risk for terrestrial and freshwater species and severely disrupting ecosystems across the globe. Limiting the magnitude of warming and its devastating impacts on biodiversity will require deep emissions reductions that include the rapid, large-scale deployment of low-carbon renewable energy. Concerns about potential adverse impacts to species and ecosystems from the expansion of renewable energy development will play an important role in determining the pace and scale of emissions reductions and hence, the impact of climate change on global biodiversity. Efforts are underway to reduce uncertainty regarding wildlife impacts from renewable energy development, but such uncertainty cannot be eliminated. We argue the need to accept some and perhaps substantial risk of impacts to wildlife from renewable energy development in order to limit the far greater risks to biodiversity loss owing to climate change. We propose a path forward for better reconciling expedited renewable energy development with wildlife conservation in a warming world. 相似文献
12.
In the debate on the timing of greenhouse gas emissions reductions the aspect of political feasibility has often been missing.
We introduce this aspect and show that, if we decide to delay emissions reductions, and the environmental effectiveness of
global mitigation efforts is to remain the same in terms of temperature change, we must be willing and able to undertake much
more substantial emission reductions than with early action. Even under conservative assumptions on initial political feasibility
(maximum 0.25% year-on-year reductions), a 20-year delay means that we must reduce emissions at an annual rate that is 5 to
11 times greater than with early climate action. Our capacity for technological progress, political change and the inertia
of the socio-economic system gives us reason to be concerned about our ability to achieve such higher rates of emission reductions.
If we are not able to achieve such higher rates, delaying action will inevitably result in higher temperatures in 2100. Unless
we are willing to accept higher temperatures, choosing to delay climate action is a gamble that political feasibility will
increase over time as a result of the delay itself. 相似文献
13.
Abstract This article introduces and explores a new form of international commitment to limit greenhouse gas (GHG) emissions, called an action target. Action targets differ from other forms of targets, such as the Kyoto Protocol's fixed targets, in that they define a quantity of GHG abatement to be achieved, rather than a future emission level to be reached. This article explains the basic mechanics of how action targets might operate, and analyses the approach across a range of criteria, including uncertainty management and contributions to sustainable development in non-Annex I (developing) countries. The analysis suggests that action targets might improve the prospects of widening and deepening developing country participation in the international climate regime. 相似文献
14.
Nathan Rive Asbjørn Torvanger Terje Berntsen Steffen Kallbekken 《Climatic change》2007,82(3-4):373-391
The question of appropriate timing and stringency of future greenhouse gas (GHG) emission reductions remains an issue in the
discussion of mitigation responses to the climate change problem. It has been argued that our near-term action should be guided
by a long-term vision for the climate, possibly a long-term temperature target. In this paper, we review proposals for long-term
climate targets to avoid ‘dangerous’ climate change. Using probability estimates of climate sensitivity from the literature,
we then generate probabilistic emissions scenarios that satisfy temperature targets of 2.0, 2.5, and 3.0°C above pre-industrial
levels with no overshoot. Our interest is in the implications of these targets on abatement requirements over the next 50 years.
If we allow global industrial GHG emissions to peak in 2025 at 14 GtCeq, and wish to achieve a 2.0°C target with at least
50% certainty, we find that the low sensitivity estimate in the literature suggests our industrial emissions must fall to
9 GtCeq by 2050: equal to the level in 2000. However, the average literature sensitivity estimate suggests the level must
be less than 2 GtCeq; and in the high sensitivity case, the target is simply unreachable unless we allow for overshoot. Our
results suggest that in light of the uncertainty in our knowledge of the climate sensitivity, a long-term temperature target
(such as the 2.0°C target proposed by the European Commission) can provide limited guidance to near-term mitigation requirements. 相似文献
15.
《Global Environmental Change》1999,9(3):221-232
Various aspects of the role of uncertainty in greenhouse gas emission reduction policy are analyzed with the integrated assessment model FUND. FUND couples simple models of economy, climate, climate impacts, and emission abatement. Probability distribution functions are assumed for all major parameters in the model. Monte Carlo analyses are used to study the effects of parametric uncertainties. Uncertainties are found to be large and grow over time. Uncertainties about climate change impacts are more serious than uncertainties about emission reduction costs, so that welfare-maximizing policies are stricter under uncertainty than under certainty. This is more pronounced without than with international cooperation. Whether or not countries cooperate with one another is more important than whether or not uncertainty is considered. Meeting exogenously defined emission targets may be more or less difficult under uncertainty than under certainty, depending on the asymmetry in the uncertainty and the central estimate of interest. The major uncertainty in meeting emissions targets in each of a range of possible future is the timing of starting (serious) reduction policies. In a scenario aiming at a stable CO2 concentration of 550 ppm, the start date varies 20 years for Annex I countries, and much longer for non-Annex countries. Atmospheric stabilization at 550 ppm does not avoid serious risks with regard to climate change impacts. At the long term, it is possible to avoid such risks but only through very strict emission control at high economic costs. 相似文献
16.
We use an integrated assessment model of climate change to analyze how alternative decision-making criteria affect preferred investments into greenhouse gas mitigation, the distribution of outcomes, the robustness of the strategies, and the economic value of information. We define robustness as trading a small decrease in a strategy’s expected performance for a significant increase in a strategy’s performance in the worst cases. Specifically, we modify the Dynamic Integrated model of Climate and the Economy (DICE-07) to include a simple representation of a climate threshold response, parametric uncertainty, structural uncertainty, learning, and different decision-making criteria. Economic analyses of climate change strategies typically adopt the expected utility maximization (EUM) framework. We compare EUM with two decision criteria adopted from the finance literature, namely Limited Degree of Confidence (LDC) and Safety First (SF). Both criteria increase the relative weight of the performance under the worst-case scenarios compared to EUM. We show that the LDC and SF criteria provide a computationally feasible foundation for identifying greenhouse gas mitigation strategies that may prove more robust than those identified by the EUM criterion. More robust strategies show higher near-term investments in emissions abatement. Reducing uncertainty has a higher economic value of information for the LDC and SF decision criteria than for EUM. 相似文献
17.
《Climate Policy》2013,13(3):191-205
Abstract In response to Article 2.2 of the Kyoto Protocol, the International Maritime Organisation (IMO) and the International Civil Aviation Organisation (ICAO) have begun to consider greenhouse gas (GHG) emissions from international aviation and shipping. However, neither ICAO nor IMO have taken any effective action on the issue yet and progress can be characterised as slow. The lack of action has so far not been made up for by measures within the climate change regime or by individual countries. An important motivation for the efforts of ICAO and IMO so far has been the potential regulatory competition with the climate change regime. However, given the lack of political will to act on the issue within the latter, this motivation has not been very forceful. Against this backdrop, I argue that there are in particular three options for furthering progress within ICAO and IMO, namely (1) enhancing the threat of regulation of GHG emissions from international transport under the climate change regime; (2) undertaking unilateral domestic action by various countries (in particular the EU); and (3) furthering a learning process within ICAO and IMO. Furthermore, a closer coordination of efforts under ICAO, IMO and the climate change regime could facilitate and accelerate progress. 相似文献
18.
J. Gordon Arbuckle Jr. Linda Stalker Prokopy Tonya Haigh Jon Hobbs Tricia Knoot Cody Knutson Adam Loy Amber Saylor Mase Jean McGuire Lois Wright Morton John Tyndall Melissa Widhalm 《Climatic change》2013,117(4):943-950
A February 2012 survey of almost 5,000 farmers across a region of the U.S. that produces more than half of the nation’s corn and soybean revealed that 66 % of farmers believed climate change is occurring (8 % mostly anthropogenic, 33 % equally human and natural, 25 % mostly natural), while 31 % were uncertain and 3.5 % did not believe that climate change is occurring. Results of initial analyses indicate that farmers’ beliefs about climate change and its causes vary considerably, and the relationships between those beliefs, concern about the potential impacts of climate change, and attitudes toward adaptive and mitigative action differ in systematic ways. Farmers who believed that climate change is occurring and attributable to human activity were significantly more likely to express concern about impacts and support adaptive and mitigative action. On the other hand, farmers who attributed climate change to natural causes, were uncertain about whether it is occurring, or did not believe that it is occurring were less concerned, less supportive of adaptation, and much less likely to support government and individual mitigative action. Results suggest that outreach with farmers should account for these covariances in belief, concerns, and attitudes toward adaptation and mitigation. 相似文献
19.
《Global Environmental Change》2007,17(1):59-72
Projections of future climate change are plagued with uncertainties, causing difficulties for planners taking decisions on adaptation measures. This paper presents an assessment framework that allows the identification of adaptation strategies that are robust (i.e. insensitive) to climate change uncertainties. The framework is applied to a case study of water resources management in the East of England, more specifically to the Anglian Water Services’ 25 year Water Resource Plan (WRP). The paper presents a local sensitivity analysis (a ‘one-at-a-time’ experiment) of the various elements of the modelling framework (e.g., emissions of greenhouse gases, climate sensitivity and global climate models) in order to determine whether or not a decision to adapt to climate change is sensitive to uncertainty in those elements.Water resources are found to be sensitive to uncertainties in regional climate response (from general circulation models and dynamical downscaling), in climate sensitivity and in climate impacts. Aerosol forcing and greenhouse gas emissions uncertainties are also important, whereas uncertainties from ocean mixing and the carbon cycle are not. Despite these large uncertainties, Anglian Water Services’ WRP remains robust to the climate change uncertainties sampled because of the adaptation options being considered (e.g. extension of water treatment works), because the climate model used for their planning (HadCM3) predicts drier conditions than other models, and because ‘one-at-a-time’ experiments do not sample the combination of different extremes in the uncertainty range of parameters. This research raises the question of how much certainty is required in climate change projections to justify investment in adaptation measures, and whether such certainty can be delivered. 相似文献
20.
Climate change and sustainable development: towards dialogue 总被引：2，自引：0，他引：2
Stewart Cohen David Demeritt John Robinson Dale Rothman 《Global Environmental Change》1998,8(4):341-371
The consequences of climate change and sustainable development remaining as separate discourses are explored, both in general and in the Canadian context. One of these consequences is the difference in emission and economic development scenarios generated by the two groups. A second is that strategies to reduce greenhouse gas emissions are designed and assessed in a narrow technical context, divorced from the economic and social forces that underlie them. We identify the need for climate change and sustainable development to be represented in a more explicit manner in each other's research agendas, and for integrated assessment of climate change to incorporate alternative methodologies that complement global scale integrated assessment models. These methodologies should include greater involvement of stakeholders as partners with researchers in a shared learning experience. 相似文献