Estimating the Impact of Climate Change on Agriculture in Low-Income Countries: Household Level Evidence from the Nile Basin, Ethiopia

This paper presents an empirical analysis of the impact of climate change on agriculture in a typical developing country. The economic implications of climate change are estimated by using both a farm productivity and a Ricardian framework. Data are drawn from about 1,000 farms producing cereal crops in the Nile Basin of Ethiopia. The thin plate spline method of spatial interpolation was used to predict household specific rainfall and temperature values using meteorological station data collected for 30?years across the regions. We found that climate change adaptation has a significant impact on both farm productivity and farm net revenues. We complement the analysis by providing an estimation of the determinants of adaptation. Extension services (both formal and farmer to farmer), as well as access to credit and information on future climate changes are key drivers of adaptation.     

Climate Change and Adaptation: The Case of Nigerian Agriculture

The present research offers an economic assessment of climate change impacts on the four major crop families characterizing Nigerian agriculture. The evaluation is performed by shocking land productivity in a computable general equilibrium model tailored to replicate Nigerian economic development up to 2050. The detail of land uses in the model has been increased by differentiating land types per agro-ecological zones. Uncertainty about future climate is captured, using, as inputs, yield changes computed by a crop model under ten general circulation models runs. Climate change turns out to be negative for Nigeria in the medium term, with production losses and increase in crop prices, higher food dependency on foreign imports, and GDP losses in all the simulations after 2025. In a second part of the paper, a cost effectiveness analysis of adaptation in Nigerian agriculture is conducted. The adaptation practices considered are a mix of cheaper “soft measures” and more costly “hard” irrigation expansion. The main result is that the cost effectiveness of the whole package depends crucially on the possibility of implementing adaptation by exploiting low-cost opportunities which show a benefit-cost ratio larger than one in all the climate regimes.     

Adaptation to Climate Change: Commitment and Timing Issues

We study the impact of timing and commitment on adaptation and mitigation policies in the context of international environmental problems. Adaptation policies present the characteristics of a private good and may require a prior investment, while mitigation policies produce a public good. In a stylized model, we evaluate the impact of strategic commitment and leadership considerations when countries with different attitudes towards environmental cooperation coexist. We obtain equilibrium abatement and adaptation levels and environmental costs under partial cooperation for various timing and leadership scenarios. Crucially, global environmental costs suffered by countries are found to be greater when adaptation measures can be used strategically.     

Environmental Policy in the Presence of Induced Technological Change

We examine the hypothesis that induced technological change (ITC) can dramatically lower the cost of a carbon tax in a static optimal tax model. The research and development sector is represented by an aggregate stock of energy-saving technology, which acts as a weak substitute with a polluting resource in the energy generation sector. Using this model, we analytically show how ITC occurs and affects the cost of a carbon tax. Applying quantitative estimates of the size of ITC to numerical simulations calibrated to the US economy, we find that existing empirical evidence can reduce the welfare cost of environmental tax reform by 12%. Our tests of alternative parameters show that this result is highly sensitive to the assumptions used, suggesting that ITC could result in much larger reductions in cost.     

气候变化视野中的自愿环境协议

气候变化问题的综合性和广泛性决定整个社会每一分子都直接或间接地对气候变化有不可分割的作用。传统环境治理思想过多地将环境管理和提高义务置于诸如政府、环保团体等公共利益卫道士之手,单纯依靠公共利益团体的力量在气候变化背景下已不足以形成有效的社会约束机制,许多高瞻远瞩的企业已意识到自身环境责任与社会形象的重要性,通过自我约束行为为缓解气候变化添砖加瓦,自愿环境协议为此提供了制度平台。国际上早已有将自愿环境协议作为气候变化应对战略的一项重要措施的实践,我国的相关试点工作也已悄然铺开。因此,如何正视自愿环境协议的柔性治理功能,以及如何促进其在我国气候变化应对机制中发挥正面作用,成为我国环境治理面临的新问题。     

中国适应气候变化的科技政策变迁与展望

适应气候变化的科技政策是该领域科技活动的重要保障。以2007—2020年期间212份适应气候变化的中央科技政策文件作为分析样本,采用共词和聚类方法,分析不同时期适应性科技政策主题聚焦点演进和变化。研究结果显示,“技术研发”“技术成果应用推广”“资金保障”“监测应急能力发展规划”“水利科技发展支持”等主题发生了明显的政策逻辑变迁。整体来看,适应性科技政策呈现密切结合国家气候适应战略演进而深化发展的特点,未来中国适应气候变化的科技政策应进一步引导适应技术科研方向,助力气候适应科技成果转化,提供财政、信息等资源支持。     

适应气候变化障碍研究综述

应对气候变化已经成为全世界共同面临的紧迫任务,适应气候变化是更为现实的重要选择,而减少或消除适应气候变化障碍是适应过程的关键。适应气候变化障碍是指在挖掘适应气候变化潜力的过程中,通过政策、计划或措施能够消除或减少的约束。文章在阐述适应气候变化障碍研究意义的基础上,初步总结了国内外对适应气候变化障碍及其适应对策的相关研究,简单介绍了一种适应气候变化的研究方法——社会生态系统诊断框架,最后对未来的研究方向和发展动态提出了相应的建议,希望可以为未来适应气候变化的研究提供理论参考。同时,强调在现有政策框架和发展规划中,兼顾适应气候变化需要,以减少适应成本和适应障碍。     

地方政府处在应对气候变化的最前线——澳大利亚《地方政府气候变化适应行动》述评

近年来,气候变化成为与人类社会发展和生存密切相关的全球性热点。澳大利亚受到气候变化的严重影响。然而,长期以来,澳大利亚政府在应对气候变化方面一直落后于整体发达国家。自2006年开始,以《地方政府气候变化适应行动》的出台为标志,澳大利亚政府的态度发生了积极的变化。文章对澳大利亚应对气候变化影响的相关背景和举措以及澳大利亚环境和水资源部出台的《地方政府气候变化适应行动》报告进行了介绍和评述,并结合该报告观点及我国实际情况提出了相应的启示和建议。     

Farm-level Autonomous Adaptation of European Agricultural Supply to Climate Change

The impact of climate change on European agriculture is subject to a significant uncertainty, which reflects the intertwined nature of agriculture. This issue involves a large number of processes, ranging from field to global scales, which have not been fully integrated yet. In this study, we intend to help bridging this gap by quantifying the effect of farm-scale autonomous adaptations in response to changes in climate. To do so, we use a modelling framework coupling the STICS generic crop model to the AROPAj microeconomic model of European agricultural supply. This study provides a first estimate of the role of such adaptations, consistent at the European scale while detailed across European regions. Farm-scale autonomous adaptations significantly alter the impact of climate change over Europe, by widely alleviating negative impacts on crop yields and gross margins. They significantly increase European production levels. However, they also have an important and heterogeneous impact on irrigation water withdrawals, which exacerbate the differences in ambient atmospheric carbon dioxide concentrations among climate change scenarios.     

低碳农业发展核心目标:减缓和适应气候变化

减缓和适应是人类应对气候变化行动中两种相辅相成的措施。中国农业在应对气候变化中,减缓和适应同等重要:一方面,农业在减缓气候变化中具有独特的作用;另一方面,农业适应气候变化比减缓气候变化更为现实的迫切。积极发展低碳现代农业实现减排增汇,中国农业生态系统可以作为一种非常重要的固碳增汇措施,纳入全球CO2减排措施中去。中国低碳农业在减缓和适应气候变化中具有巨大潜力。     

基于气候变化脆弱性的适应规划:一个福利经济学分析

气候变化是典型的具有复杂性、长期性和外部性的全球环境问题。气候变化的福利影响及其成本效益评估是适应气候变化的决策基础。本文基于气候变化科学的基本概念和福利经济学理论,构建了柏格森-萨缪尔森社会福利函数,评估了气候变化背景下的社会经济脆弱性与经济福利风险,提出了适用于中国国情的适应规划路径。首先,基于社会福利核心要素的气候变化脆弱性评估结果表明,气候敏感性是影响中国不同地区福利水平和脆弱性的重要因子。其次,依据气候敏感性与适应能力将中国30多个省份划分为三类适应区:发展型适应优先区、增量型适应优先区、发展型与增量型并重地区。第三,采用地区加权方法测算了中国2016—2030年RCP8.5气候变化情景下的气候灾害经济损失及福利风险,提出依据能力原则、需求原则或最脆弱地区优先原则分别由地方政府、部门或中央主导的适应规划设计。     

Risk Preferences and Environmental Uncertainty: Implications for Crop Diversification Decisions in Ethiopia

To the extent that diversifying income portfolio is used as a strategy for shielding against production risk, both individual risk aversion and weather uncertainty could affect crop diversification decisions. This paper is concerned with empirically assessing the effects of risk aversion and rainfall variability on farm level diversity. Unique panel data from Ethiopia consisting of experimentally generated risk aversion measures combined with rainfall data are employed in the analysis. The major contribution of this study is its explicit treatment of individual risk preferences in the decision to diversify, simultaneously controlling for environmental risk in the form of rainfall variability. Covariate shocks from rainfall variability are found to positively contribute to an increased level of diversity with individual risk aversion having a positive but less significant role. We find that rainfall variability in spring has a greater effect than rainfall variability summer??the major rainy season. This finding is in line with similar agronomic-meteorological studies. These results imply that in situ biodiversity conservation could be effective in areas with high rainfall variability. However, reduction in risk aversion, which is associated with poverty reduction, is likely to reduce in situ conservation.     

气候变化对欧洲农业的系统影响及对策

本文基于欧洲气候变化的历史演进与未来情景,系统分析了气候变化对欧洲农业的历史和潜在影响,提供了欧洲农业应对气候变化的适应性措施,及其对中国未来农业发展的启示和建议。     

气候变化下中国生态适应性设计在国土空间规划中的策略及本土化：定义、理念框架与解读

长期气候变化和极端天气事件给中国城乡可持续发展带来考验,而城乡地区自身的适应性规划体系不完善及生态环境恶化让城市适应性提升面临压力。因此,以“无悔”设计和可持续发展为基础的生态适应性(Ecological-based Adaptation,EbA)理念和措施逐渐引起国内学者的研究和关注。在收集和总结相关国际案例及应用的基础上,对EbA理论、理念及研究进展进行深入分析和探讨。以生态适应性规划为着眼点,对分析的成果进行归纳,从研究和决策2个方面提出新的本地化解读、未来研究趋势及应用特点。同时结合中国开放空间规划体系的改革现状,提出适用于中国城乡可持续发展及韧性体系构建的本土化理念框架和相关建议。     

Exchanging Goods and Damages: The Role of Trade on the Distribution of Climate Change Costs

The impacts of climate change vary significantly across world regions. Whereas tropical and subtropical regions are expected to suffer severely from the effects of climate change, the impacts in northern latitudes should remain relatively moderate. However, regions are not self-sufficient, and the costs of climate change can spread across regions through international trade. I study the international spillover of climate impacts within a regionalised, climate-sensitive, dynamic computable general equilibrium model of the world economy. Using data from a global climate model shows that the world regions face welfare losses between 0.6 and 2.1 % due to climate change. I also show that climate change affects terms of trade and sectoral competitiveness. By means of a decomposition method, the extent of spillover impacts through international trade can be identified. Spillover impacts significantly affect, either positively or negatively, the total costs of climate change for a region. For regions with low exposure to climate change and high adaptive capacities, spillover effects are responsible for a 1/6 of the total cost of climate change.     

Environmental Taxation and Induced Structural Change in an Open Economy: The Role of Market Structure

Abstract. Studies of structural change induced by environmental taxation usually proceed in a perfect-competition framework and typically find structural change to be quite moderate under realistic emission reduction scenarios. By observing that some of the industries affected are likely to operate under imperfect rather than perfect competition, additional mechanisms emerge which may amplify structural change beyond the extent identified as yet. Especially, changes in economies of scale may arise which weaken or strengthen the competitive position of industries over and above the initial cost effect. Using a computable general equilibrium model for Germany to examine the effects of a unilaterally introduced carbon tax, we find that induced structural change is more pronounced under imperfect competition than under perfect competition. At the macroeconomic level, we find that aggregate losses in economies of scale are larger than aggregate gains, implying that the total costs of environmental regulation are higher under imperfect competition than under perfect competition.     

Environmental Liability Law and Induced Technical Change – The Role of Discounting

We analyse the incentives of environmental liability law for inducing progress to emission abatement technology. We consider three liability rules: strict liability, a negligence rule with an emission norm as the due care standard, and a double negligence rule which combines the emission standard with an abatement technology norm. In the case of distortive discounting, i.e. where the private discount rate deviates from the social one, we show, how the level of distortion influences the ranking of liability rules, according to the criterion of generated social cost.