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1.
The International Workshop on Reducing Vulnerability of Agriculture and Forestry to Climate Variability and Climate Change held in Ljubljana, Solvenia, from 7 to 9 October 2002 addressed a range of important issues relating to climate variability, climate change, agriculture, and forestry including the state of agriculture and forestry and agrometeological information, and potential adaptation strategies for agriculture and forestry to changing climate conditions and other pressures. There is evidence that global warming over the last millennium has already resulted in increased global average annual temperature and changes in rainfall, with the 1990s being likely the warmest decade in the Northern Hemisphere at least. During the past century, changes in temperature patterns have, for example, had a direct impact on the number of frost days and the length of growing seasons with significant implications for agriculture and forestry. Land cover changes, changes in global ocean circulation and sea surface temperature patterns, and changes in the composition of the global atmosphere are leading to changes in rainfall. These changes may be more pronounced in the tropics. For example, crop varieties grown in the Sahel may not be able to withstand the projected warming trends and will certainly be at risk due to projected lower amounts of rainfall as well. Seasonal to interannual climate forecasts will definitely improve in the future with a better understanding of dynamic relationships. However, the main issue at present is how to make better use of the existing information and dispersion of knowledge to the farm level. Direct participation by the farming communities in pilot projects on agrometeorological services will be essential to determine the actual value of forecasts and to better identify the specific user needs. Old (visits, extension radio) and new (internet) communication techniques, when adapted to local applications, may assist in the dissemination of useful information to the farmers and decision makers. Some farming systems with an inherent resilience may adapt more readily to climate pressures, making long-term adjustments to varying and changing conditions. Other systems will need interventions for adaptation that should be more strongly supported by agrometeorological services for agricultural producers. This applies, among others, to systems where pests and diseases play an important role. Scientists have to guide policy makers in fostering an environment in which adaptation strategies can be effected. There is a clear need for integrating preparedness for climate variability and climate change. In developed countries, a trend of higher yields, but with greater annual fluctuations and changes in cropping patterns and crop calendars can be expected with changing climate scenarios. Shifts in projected cropping patterns can be disruptive to rural societies in general. However, developed countries have the technology to adapt more readily to the projected climate changes. In many developing countries, the present conditions of agriculture and forestry are already marginal, due to degradation of natural resources, the use of inappropriate technologies and other stresses. For these reasons, the ability to adapt will be more difficult in the tropics and subtropics and in countries in transition. Food security will remain a problem in many developing countries. Nevertheless, there are many examples of traditional knowledge, indigenous technologies and local innovations that can be used effectively as a foundation for improved farming systems. Before developing adaptation strategies, it is essential to learn from the actual difficulties faced by farmers to cope with risk management at the farm level. Agrometeorologists must play an important role in assisting farmers with the development of feasible strategies to adapt to climate variability and climate change. Agrometeorologists should also advise national policy makers on the urgent need to cope with the vulnerabilities of agriculture and forestry to climate variability and climate change. The workshop recommendations were largely limited to adaptation. Adaptation to the adverse effects of climate variability and climate change is of high priority for nearly all countries, but developing countries are particularly vulnerable. Effective measures to cope with vulnerability and adaptation need to be developed at all levels. Capacity building must be integrated into adaptation measures for sustainable agricultural development strategies. Consequently, nations must develop strategies that effectively focus on specific regional issues to promote sustainable development.  相似文献   

2.
This article addresses the question of how forestry projects, given the recently improved standards for the accounting of carbon sequestration, can benefit from existing and emerging carbon markets in the world. For a long time, forestry projects have been set up for the purpose of generating carbon credits. They were surrounded by uncertainties about the permanence of carbon sequestration in trees, potential replacement of deforestation due to projects (leakage), and how and what to measure as sequestered carbon. Through experience with Joint Implementation (JI) and Clean Development Mechanism (CDM) forestry projects, albeit limited, and with forestry projects in voluntary carbon markets, considerable improvements have been made with accounting of carbon sequestration in forests, resulting in a more solid basis for carbon credit trading. The scope of selling these credits exists both in compliance markets, although currently with strong limitations, and in voluntary markets for offsetting emissions with carbon credits. Improved carbon accounting methods for forestry investments can also enhance the scope for forestry in the Nationally Determined Contributions (NDCs) that countries must prepare under the Paris Agreement.

POLICY RELEVANCE

This article identifies how forestry projects can contribute to climate change mitigation. Forestry projects have addressed a number of challenges, like reforestation, afforestation on degraded lands, and long-term sustainable forest management. An interesting new option for forestry carbon projects could be the NDCs under the Paris Agreement in December 2015. Initially, under CDM and JI, the number of forestry projects was far below that for renewable energy projects. With the adoption of the Paris Agreement, both developed and developing countries have agreed on NDCs for country-specific measures on climate change mitigation, and increased the need for investing in new measures. Over the years, considerable experience has been built up with forestry projects that fix CO2 over a long-term period. Accounting rules are nowadays at a sufficient level for the large potential of forestry projects to deliver a reliable, additional contribution towards reducing or halting emissions from deforestation and forest degradation activities worldwide.  相似文献   


3.
Many decisions concerning long-lived investments already need to take into account climate change. But doing so is not easy for at least two reasons. First, due to the rate of climate change, new infrastructure will have to be able to cope with a large range of changing climate conditions, which will make design more difficult and construction more expensive. Second, uncertainty in future climate makes it impossible to directly use the output of a single climate model as an input for infrastructure design, and there are good reasons to think that the needed climate information will not be available soon. Instead of optimizing based on the climate conditions projected by models, therefore, future infrastructure should be made more robust to possible changes in climate conditions. This aim implies that users of climate information must also change their practices and decision-making frameworks, for instance by adapting the uncertainty-management methods they currently apply to exchange rates or R&D outcomes. Five methods are examined: (i) selecting “no-regret” strategies that yield benefits even in absence of climate change; (ii) favouring reversible and flexible options; (iii) buying “safety margins” in new investments; (iv) promoting soft adaptation strategies, including long-term prospective; and (v) reducing decision time horizons. Moreover, it is essential to consider both negative and positive side-effects and externalities of adaptation measures. Adaptation–mitigation interactions also call for integrated design and assessment of adaptation and mitigation policies, which are often developed by distinct communities.  相似文献   

4.
Land-use, land-use change and forestry (LULUCF) activities will play an important role in global climate change mitigation. Many carbon schemes require the delivery of both climate and rural development benefits by mitigation activities conducted in developing countries. Agroforestry is a LULUCF activity that is gaining attention because of its potential to deliver climate benefits as well as rural development benefits to smallholders. There is hope that agroforestry can deliver co-benefits for climate and development; however experience with early projects suggests co-benefits are difficult to achieve in practice. We review the literature on agroforestry, participatory rural development, tree-based carbon projects and co-benefit carbon projects to look at how recommended project characteristics align when trying to generate different types of benefits. We conclude that there is considerable tension inherent in designing co-benefit smallholder agroforestry projects. We suggest that designing projects to seek ancillary benefits rather than co-benefits may help to reduce this tension.  相似文献   

5.
The Kyoto Protocol introduces the possibility that changes in carbon stock on agricultural and forest land and soils may be counted against countries’ commitments to reduce their greenhouse gas emissions. Including activities related to land use change and forestry in the international climate change agreement may stimulate new incentives for soil-conservation practices domestically. However, a primary criteria for their inclusion relates to the level of accuracy and transparency with which carbon stock changes can be assessed. Parties will also be concerned with the wider environmental impact of different sequestration practices, and the impact of offsets on overall emissions targets. This paper examines these issues for agricultural soils, considering recent research in North America. It is argued that incentives for carbon sequestration practices may need to be implemented independently of actual stock changes because farm-level soil monitoring would be very costly. In the USA, priority should be given to establishing incentives for cover crops and to expanding conservation tillage programs. These activities provide a range of ancillary environmental benefits. In contrast, improvements in biomass yield tend to rely on higher fertilizer inputs with their related environmental costs. Carbon accumulated through any of these activities is easily lost if the practices are discontinued, and so assessment procedures are needed that would avoid overestimating sequestration. Annual accumulation in agricultural soils could be equivalent to about 10% of Annex I carbon dioxide emissions, and therefore options for limiting sink credits from soils should be considered.  相似文献   

6.
The research was designed to answer how households and local communities in rural Nepal are responding to the impacts of climate change. Using four villages as case study units, a mixed method approach was adopted in a multi-scaled process carried out at community, district and national levels. The research found that adaptation practices being adopted differ according to household well-being and are largely governed by access to education, information and resources within the community. Responses such as livelihood and income diversification, internal migration, share cropping, taking consumption loans, use of alternative energy and use of bio-pesticides were found to mostly vary according to well-being status of the interviewees. Development of adaptation plans, strategies and support mechanisms should take account of the different adaptation practices and needs of households. If such individual situations are not considered, adaptation responses may be ineffective or even be maladaptive and increase vulnerability. The research also found that the autonomous, unplanned and reactive nature of adaptation practices chosen by rural communities can contribute to further inequity and unequal power relations. The knowledge generated from this research contributes to understanding of how climate change contributes to vulnerability, but also how local practices and lack of an effective climate policy or response measures may magnify the effects of many existing drivers of vulnerability in terms of maladaptation and increasing social inequalities.  相似文献   

7.
Climate change will injure vulnerable communities. In response, coordinated global action has emerged to mitigate climate change, to gauge and map climate-related risks, and to plan for adaptation, which in turn has opened new avenues of funding, power, knowledge and opportunity. The identification of climate risks, analysis and diffusion of ‘impact’ scenarios, incorporation of carbon into economic regimes, and interventions to enhance adaptive capacity will necessarily be experienced differently by different groups. As climate-related crises produce winners and losers, so may discourses and plans made to avert such crises. In the process both the bio-physical events and the social responses shape and reshape social stratification and the distribution of risk. They produce new inequalities and needs for new kinds of responses to guard against injustice. From the emergence of desalination water projects and contested water access, to relocation planning in the Arctic and the South Pacific due to sea-level rise, to increasingly centralized forest management; mitigation and adaptation responses and interventions create their own critical outcomes. This essay and the articles in this special issue examine some new opportunities and risks associated with climate-change discourses and interventions. This special issue shows that vulnerable communities may be at risk of material injury following climate change or climate change intervention; and, be further insulted and injured by lack of representation and recognition, and by misrecognition as simplified, stereotyped victims in local, national and international climate conversations. Using a mixture of theoretical insight and case study research, this collection of articles explores the injuries of climate change as it applies to both direct physical stress scenarios and exposure to adaptation and mitigation policies and planning, as well as the discursive insults of being discounted, stereotyped, or ignored.  相似文献   

8.
Forests have an important role to play in climate change mitigation through carbon sequestration and wood supply. However, the lower albedo of mature forests compared to bare land implies that focusing only on GHG accounting may lead to biased estimates of forestry's total climatic impacts. An economic model with a high degree of detail of the Norwegian forestry and forest industries is used to simulate GHG fluxes and albedo impacts for the next decades. Albedo is incorporated in a carbon tax/subsidy scheme in the Norwegian forest sector using a partial, spatial equilibrium model. While a price of EU€100/tCO2e that targets GHG fluxes only results in reduced harvests, the same price including albedo leads to harvest levels that are five times higher in the first five years, with 39% of the national productive forest land base being cleared. The results suggest that policies that only consider GHG fluxes and ignore changes in albedo will not lead to an optimal use of the forest sector for climate change mitigation.

Policy relevance

Bare land reflects a larger share of incoming solar energy than dense forest and thus has higher albedo. Earlier research has suggested that changes in albedo caused by management of boreal forest may be as important as carbon fluxes for the forest's overall global warming impacts. The presented analysis is the first attempt to link albedo to national-scale forest climate policies. A policy with subsidies to forest owners that generate carbon sequestration and taxes levied on carbon emissions leads to a reduced forest harvest. However, including albedo in the policy alongside carbon fluxes yields very different results, causing initial harvest levels to increase substantially. The inclusion of albedo impacts will make harvests more beneficial for climate change mitigation as compared to a carbon-only policy. Hence, it is likely that carbon policies that ignore albedo will not lead to optimal forest management for climate change mitigation.  相似文献   

9.
IPCC第六次评估报告(AR6)第二工作组(WGII)报告的第二章表明,气候变化对陆地和淡水生态系统影响的范围和程度较前期评估结果更为严峻。人为气候变化导致生态系统结构、功能和恢复力恶化,生物群落转移,疾病的传播范围和发病率增加,野火燃烧面积增加和持续时间延长,局部地区物种灭绝,极端天气的频率和强度增加。未来气温升高2~4℃情景下,陆地和淡水生态系统中高灭绝风险物种占比为10%~13%,野火燃烧面积增加35%~40%,森林地区50%以上树木面临死亡风险,15%~35%的生态系统结构发生转变,碳损失持续增加,气温的升高将进一步加剧这些风险造成的严重且不可逆的影响。通过生态系统保护和恢复等人为适应和减缓措施,可以在一定程度的气候变化范围内保护生态系统的生物多样性并增强生态系统服务在气候变化下的恢复力。加剧的气候变化将阻碍适应措施的制定和实施,为保证措施的有效性需要考虑气候变化的长期影响并加快适应措施的部署。  相似文献   

10.
There is a general consensus that climate change will increase the frequency and severity of freshwater flooding in many parts of the world. Communities prone to such flooding have struggled to understand the manner in which this will affect them (in both economic and social terms) and the appropriate way to adapt. In this study, we conduct a case-study investigation into the costs of freshwater flooding due to climate change along the Saint John River in Fredericton, NB, Canada. We develop a four-step framework that combines extreme event analysis, downscaled general circulation models, hydrologic analysis, and the contingent valuation method. Using this framework, together with primary data on a 2005 flooding event, we estimate market and non-market annual average flood damage under a number of climate and population scenarios. We find that non-market costs can represent up to 50% of total household costs of flooding events, and 23–42% of the total costs of flooding due to climate change, depending on the different climate and population scenarios considered. Incorporating such costs into flood adaptation planning may substantially increase support for active adaptation activities, especially in ‘worst case’ climate scenarios.  相似文献   

11.
Agricultural Impact Assessment, Vulnerability, and the Scope for Adaptation   总被引:1,自引:1,他引:0  
Climate change assessments which have considered climate impacts of a 2xCO2 climate, using models of the global agricultural system, have found small impacts on overall production, but larger regional changes. Production shifts among regions can be considered one mechanism for adaptation. Adaptation at the farm level, through changes in crops, cultivars, and production practices, is another adaptation mechanism. Existing studies differ in how important these mechanisms will be. Studies that have considered yield effects at specific sites have found very wide ranges of impacts. A useful way to evaluate the impacts of climate change, given the uncertainty about future impacts, is to consider vulnerability. Studies have defined vulnerability in terms of yield, farm profitability, regional economy, and hunger. Vulnerability and climate impacts, particularly in terms of higher order effects on profitability and sustainability, will depend on how society and the economy develop. Lower income populations and marginal agricultural regions, particularly arid or flood prone areas, are most vulnerable to climate change.  相似文献   

12.
Agriculture and forestry will be particularly sensitive to changes in mean climate and climate variability in the northern and southern regions of Europe. Agriculture may be positively affected by climate change in the northern areas through the introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. The disadvantages may be determined by an increase in need for plant protection, risk of nutrient leaching and accelerated breakdown of soil organic matter. In the southern areas the benefits of the projected climate change will be limited, while the disadvantages will be predominant. The increased water use efficiency caused by increasing CO2 will compensate for some of the negative effects of increasing water limitation and extreme weather events, but lower harvestable yields, higher yield variability and reduction in suitable areas of traditional crops are expected for these areas. Forestry in the Mediterranean region may be mainly affected by increases in drought and forest fires. In northern Europe, the increased precipitation is expected to be large enough to compensate for the increased evapotranspiration. On the other hand, however, increased precipitation, cloudiness and rain days and the reduced duration of snow cover and soil frost may negatively affect forest work and timber logging determining lower profitability of forest production and a decrease in recreational possibilities. Adaptation management strategies should be introduced, as effective tools, to reduce the negative impacts of climate change on agricultural and forestry sectors.  相似文献   

13.
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   

14.
林业行业应对气候变化的措施和成效   总被引:1,自引:0,他引:1  
从植树造林,发挥森林吸碳和固碳作用,加强天然林保护,提高森林的碳汇潜力两大方面,陈述了林业对减缓全球气候变化的贡献。同时介绍了国家林业局在气候变化的基础科学和应用科学研究领域,开展的卓有成效的工作;介绍了国家林业局陆地生态系统定位研究网络的基础建设、与气候变化有关的科学研究的立项与课题开展情况。最后,从探讨提高森林碳汇的方法、推进加强森林碳保护的措施、寻找林产品碳替代的途径等三方面,论述了今后一段时期林业行业在减缓气候变化中的重要任务,分析中国林业在继续增加森林面积和碳汇能力方面具有的潜力。  相似文献   

15.
Africa is thought to be the region most vulnerable to the impacts of climate variability and change. Agriculture plays a dominant role in supporting rural livelihoods and economic growth over most of Africa. Three aspects of the vulnerability of food crop systems to climate change in Africa are discussed: the assessment of the sensitivity of crops to variability in climate, the adaptive capacity of farmers, and the role of institutions in adapting to climate change. The magnitude of projected impacts of climate change on food crops in Africa varies widely among different studies. These differences arise from the variety of climate and crop models used, and the different techniques used to match the scale of climate model output to that needed by crop models. Most studies show a negative impact of climate change on crop productivity in Africa. Farmers have proved highly adaptable in the past to short- and long-term variations in climate and in their environment. Key to the ability of farmers to adapt to climate variability and change will be access to relevant knowledge and information. It is important that governments put in place institutional and macro-economic conditions that support and facilitate adaptation and resilience to climate change at local, national and transnational level.  相似文献   

16.
Previous research has identified the importance of the role of land cover in the global carbon cycle. In particular, forests have been identified as a significant carbon sink that can mitigate the rate of global climate change. Policy makers are faced with complex and difficult challenges in getting timely and useful information in monitoring global forest resources. Recent advances in the tools and methods of forest carbon accounting have produced new, innovative approaches to forest-based carbon inventories. But it is important as new tools are developed that scientists understand the needs of policy makers and that policy makers understand the capabilities and limitations of forest inventory methods. This paper explores four different policy applications that rely, or could benefit from, national carbon inventories. The goal is to help build a bridge between the communities of climate policy makers and scientists specialized in forest carbon inventories. To this end, we pursue three specific objectives: First we provide an overview for policy makers about approaches to forest carbon inventories, paying particular attention to the contributions of remote sensing technologies. Second, we outline the issues particularly relevant to forest inventory scientists who are interested in responding to public policy needs. We then discuss the tradeoffs between information cost, accuracy, precision, transparency and timeliness that need to be balanced in long-term monitoring of forest carbon. Finally, the article concludes with a series of observations and recommendations for the implementation of forest carbon inventories as increasingly central components of global climate change policy.  相似文献   

17.
未来是否会发生由大西洋热盐环流崩溃引起的气候突变是目前极富争议性的全球气候变化问题。首先回顾了过去发生的气候突变事件以及若干成因假说,介绍了McGill地球系统模拟组的有关研究成果,并探讨了过去气候突变事件中的南北半球遥相关,最后讨论了未来是否会发生大西洋热盐环流崩溃引起的气候突变。对过去发生的大西洋热盐环流突变的研究表明,它产生的气候背景与现代气候以及将来进一步变暖的气候截然不同,因此不能凭过去发生过的突变事件来推论将来会发生类似的气候突变。尽管有的气候模式预测全球变暖会导致大西洋热盐环流减弱甚至崩溃而引发气候突变,但是目前全球气候系统的观测有许多不足之处,并且现代气候模式也存在较大的不确定性,因此尚不能确信现在的全球变暖会导致这样的气候突变。  相似文献   

18.
Process-based models used to investigate forest ecosystem response to climate change were not necessarily developed to include the effect of carbon dioxide (CO2) and temperature increases on physiological processes. Simulation of the impacts of climate change with such models may lead to questionable predictions. It is generally believed that significant shifts in the performance of black spruce (Picea mariana [Mill] B.S.P.) will occur under climate change. This species, which accounts for 64% of Ontario's coniferous growing stock and 80% of the annual allowable cut, represents important economic activity throughout the boreal forest region. Forest management planning requires relatively accurate productivity estimates. Thus, it is imperative to ensure that process-based models realistically predict the effect of climate change. In this study, CENTURY and FOREST-BGC models were calibrated for a productive, upland black spruce stand in northwestern Ontario. Even though both models predicted similar relative outcomes after 100 years of climate change, they disagreed on the impacts of temperature in combination with an increase in CO2. Also, absolute amounts of carbon sequestered varied with climate change scenarios. Comparison of both models indicated that the representation of critical processes in these two forest ecosystem models is incomplete. For instance, the interactive effects of CO2 and temperature increases on physiological processes at stand and soil levels are not well documented nor are they easily identifiable in the models. Their incorporation into models is therefore problematic. Practitioners must consequently be wary of assumptions about the inclusion of critical processes in models.  相似文献   

19.
Climate change will have serious repercussions for agriculture, ecosystems, and farmer livelihoods in Central America. Smallholder farmers are particularly vulnerable due to their reliance on agriculture and ecosystem services for their livelihoods. There is an urgent need to develop national and local adaptation responses to reduce these impacts, yet evidence from historical climate change is fragmentary. Modeling efforts help bridge this gap. Here, we review the past decade of research on agricultural and ecological climate change impact models for Central America. The results of this review provide insights into the expected impacts of climate change and suggest policy actions that can help minimize these impacts. Modeling indicates future climate-driven changes, often declines, in suitability for Central American crops. Declines in suitability for coffee, a central crop in the regional economy, are noteworthy. Ecosystem models suggest that climate-driven changes are likely at low- and high-elevation montane forest transitions. Modeling of vulnerability suggests that smallholders in many parts of the region have one or more vulnerability factors that put them at risk. Initial adaptation policies can be guided by these existing modeling results. At the same time, improved modeling is being developed that will allow policy action specifically targeted to vulnerable groups, crops, and locations. We suggest that more robust modeling of ecological responses to climate change, improved representation of the region in climate models, and simulation of climate influences on crop yields and diseases (especially coffee leaf rust) are key priorities for future research.  相似文献   

20.
To succeed in meeting carbon emissions reduction targets to limit projected climate change impacts, it is imperative that improved synergies be developed between mitigation and adaptation strategies. This is especially important in development policy among remote indigenous communities, where demands for development have often not been accompanied by commensurate efforts to respond to future climate change impacts. Here we explore how mitigation and adaptation pathways can be combined to transform rural indigenous communities toward sustainability. Case studies from communities in Alaska and Nepal are introduced to illustrate current and potential synergies and trade-offs and how these might be harnessed to maximize beneficial outcomes. The adaptation pathways approach and a framework for transformational adaptation are proposed to unpack these issues and develop understanding of how positive transformational change can be supported.  相似文献   

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