Climate change and economic growth: An intertemporal general equilibrium analysis for Egypt

This study advances the state of the art in country-level computable general equilibrium analysis for climate change impact and adaptation analysis by incorporating forward-looking expectations. The analytic framework is used to explore the long-run growth prospects for Egypt in a changing climate. Based on a review of existing estimates of climate change impacts on agricultural productivity, labour productivity and the potential losses due to sea-level rise for the country, the model is used to simulate the effects of climate change on aggregate consumption, investment and income up to 2050. Available cost estimates for adaptation investments are employed to explore adaptation strategies.The simulation analysis suggests that in the absence of policy-led adaptation investments, real GDP towards the middle of the century will be 6.5% lower than in a hypothetical baseline without climate change. A combination of adaptation measures, that include coastal protection investments for vulnerable sections along the low-lying Nile delta, support for changes in crop management practices and investments to raise irrigation efficiency, could reduce the GDP loss in 2050 to around 2.6%.Further work along these lines for developing countries in climate change hotspot regions deserves a high priority on the research agenda in economic modelling.     

Economywide impacts of climate change on agriculture in Sub-Saharan Africa

Two possible adaptation scenarios to climate change for Sub-Saharan Africa are analyzed under the SRES B2 scenario. The first scenario doubles the irrigated area in Sub-Saharan Africa by 2050, compared to the baseline, but keeps total crop area constant. The second scenario increases both rainfed and irrigated crop yields by 25% for all Sub-Saharan African countries. The two adaptation scenarios are analyzed with IMPACT, a partial equilibrium agricultural sector model combined with a water simulation module, and with GTAP-W, a general equilibrium model including water resources. The methodology combines the advantages of a partial equilibrium approach, which considers detailed water-agriculture linkages, with a general equilibrium approach, which takes into account linkages between agriculture and nonagricultural sectors and includes a full treatment of factor markets. The efficacy of the two scenarios as adaptation measures to cope with climate change is discussed. Due to the limited initial irrigated area in the region, an increase in agricultural productivity achieves better outcomes than an expansion of irrigated area. Even though Sub-Saharan Africa is not a key contributor to global food production (rainfed, irrigated or total), both scenarios help lower world food prices, stimulating national and international food markets.     

Climatic impacts across agricultural crop yield distributions: An application of quantile regression on rice crops in Andhra Pradesh,India

Climatic impact on agricultural production is a serious concern, as it is directly linked to food security and poverty. Whereas there are empirical studies that examine this issue with parametric approaches focusing on the “mean” level of variables, few studies have addressed climatic impacts in general settings. Given this paucity, we characterize the impacts on crop yield distributions with a non-parametric approach. We examine the case of rice yield in Andhra Pradesh, India, an important state producing rice as a main crop but reported to be vulnerable to climate change. Employing 34 years of data, we apply quantile regressions to untangle the climatic impacts across the quantiles of rice yield, finding three main results. First, substantial heterogeneity in the impacts of climatic variables can be found across the yield distribution. Second, the direction of the climatic impacts on rice yield highly depends on agro-climatic zones. Third, seasonal climatic impacts on rice yield are significant. More specifically, a monsoon-dependent crop is more sensitive to temperature and precipitation, whereas a winter crop remains largely resilient to changes in the levels of climate variables. These findings clarify the idiosyncratic climatic impacts on agriculture in India, and call for location- and season-specific adaptation policies.     

对农民收入增长问题的一些思考

受我国农户所拥有资源的特征和农业比较效益长期下降特性的局限,农民收入问题很难从农业生产和农业政策中找到大幅度增长的出路和突破口。解决农民收入增长问题,必须跳出“农”字,扭转思维,到“非”农更广阔的领域里去寻找答案。     

Study on Medium- and Long-Term Fiscal Policies to Cope with Climate Change under the “Dual Carbon” Goals

Carbon peaking and carbon neutrality constitute an extensive, profound and systemic economic and social change. It is worthwhile to explore how fiscal policy, as a key institutional arrangement in the public policy system to cope with climate change, can play a fundamental and pillar role. Based on literatures, theories and empirical materials, this paper systematically explores the relationship between climate change and public finance. The fiscal impact of climate change will eventually be reflected in fiscal behavior, fiscal costs and fiscal relations, and the fiscal system has the adaptability of an “automatic stabilizer” and the proactiveness to enable the Discretionary Approaches function when facing climate change impacts. This implies such a governance logic of fiscal policy that is systematic, forward-looking and flexible in addressing climate change. In the future, it is necessary to further incorporate climate change or related environmental factors into the fiscal policy framework, target the two key aspects of mitigation and adaptation, and carry out a holistic, systematic and forward-looking reform of the existing fiscal expenditure policy, fiscal revenue policy, fiscal investment and financing policy, government budget system, government procurement policy and ecological compensation policy. While highlighting the “governance” function of fiscal policy in addressing climate change, Chinese government needs to strengthen the coordination and collaboration between fiscal policy tools and other public policies, and magnify the governance effectiveness of fiscal policy in the process of addressing climate change. This paper helps understand the positioning, role and influence of fiscal policy in the process of addressing climate change, provides a basis for better playing the fundamental and underpinning role of the modern fiscal system in the governance of ecological civilization, and presents an analytical framework for building a theoretical system of ecological fiscal governance.     

A general equilibrium assessment of climate change–induced loss of agricultural productivity in Nepal

The impact of climate change on agriculture has been one of the most discussed topics in the literature on climate change. Multi-regional computable general equilibrium (CGE) models have frequently been used to examine the impact of climate change on agriculture. However, these studies do not focus on country-specific issues related to the link between climate change and agriculture. This paper aims to address this gap by investigating the economy-wide impacts of climate change on Nepalese agriculture. Nepal makes an interesting case study as it has one of the most vulnerable agricultural economies in South Asia. This paper develops a comparative static multi-household CGE model to trace the direct and indirect impacts of climate change in Nepal. The results suggest that climate change has a significant negative impact on the overall Nepalese economy due to the induced loss of agricultural productivity. The results further reveal that rural households in Nepal, whose livelihoods primarily depend on subsistence farming, will face additional climate change–induced stresses due to already overstrained poverty and a weak social welfare system. The results indicate an urgent need to mainstream adaptation strategies to lessen the negative impacts of any climate change–induced loss of agricultural productivity in Nepal.     

Non-neutral information costs with match-value uncertainty

This paper investigates a model featuring a monopolist seller and a buyer with an uncertain valuation for the seller’s product. The seller chooses an information system which allows the buyer to receive a private signal, potentially correlated with her valuation. No restrictions are imposed on the conditional distributions of the signal; the cost of the information system is proportional to its precision, measured by the mutual information between the distributions of the buyer’s valuation and the signal. In equilibrium, the information system trades off the information cost against the losses deriving from a probability of trade that is either “too high,” or “too low”—depending on the relative weight of the expected losses resulting from errors of the two types—and sends “non-neutral” signals, typically. Thus, in general, the probability of a correct signal depends on the buyer’s actual valuation, and the probability of trade differs from the probability of a valuation exceeding the cost of production. The expected total surplus generated by the exchange is maximized, in equilibrium.     

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。     

Capital Malleability, Emission Leakage and the Cost of Partial Climate Policies: General Equilibrium Analysis of the European Union Emission Trading System

Computable general equilibrium (CGE) models are the premier analytical platform for assessing the economic impacts of climate change mitigation. But these models tend to treat physical capital as “malleable”, capable of reallocation among sectors over the time-period for which equilibrium is solved. Because the extent to which capital adjustment costs might dampen reallocation is not well understood, there is concern that CGE assessments understate the true costs of greenhouse gas (GHG) reduction policies. This paper uses a multi-region, multi-sector CGE model to investigate cap-and-trade schemes, such as the European Union Emission Trading System which cover a subset of the economy, elucidating the effects of capital malleability on GHG abatement, the potential for emission leakage from abating to non-abating sectors, and the impacts on welfare. To simplify the complex interactions being simulated within the CGE model, that analysis is complemented with an analytical model. A partial climate policy results in negative internal carbon leakage, with emissions declining not only in capped sectors but also in non-regulated ones. This result is stronger when capital is intersectorally mobile. Interestingly, in partial climate policy settings capital malleability can amplify or attenuate welfare losses depending on the attributes of the economy.     

GHG Targets as Insurance Against Catastrophic Climate Damages

The climate system is an angry beast and we are poking it with sticks 1 . A critical issue in climate change economics is the specification of the so‐called “damages function” and its interaction with the unknown uncertainty of catastrophic outcomes. This paper asks how much we might be misled by our economic assessment of climate change when we employ a conventional quadratic damages function and/or a thin‐tailed probability distribution for extreme temperatures. The paper gives some numerical examples of the indirect value of various greenhouse gas (GHG) concentration targets as insurance against catastrophic climate change temperatures and damages. These numerical exercises suggest that we might be underestimating considerably the welfare losses from uncertainty by using a quadratic damages function and/or a thin‐tailed temperature distribution. In these examples, the primary reason for keeping GHG levels down is to insure against high‐temperature catastrophic climate risks.     

Climate change and its marginalizing effect on agriculture

The agriculture of some areas considered marginal in the EU agricultural context is being questioned due to its low productivity and growing dependence on economic aid programs Common Agricultural Policy (CAP). This study shows that climate change increases these areas marginalisation of since worsens crop growth conditions. The influence of climate change on the agricultural sector is analyzed using the Multicriteria Decision Paradigm with information provided by the Erosion-Productivity Impact Calculator (EPIC) and a General Circulation Model (GCM) as inputs for multicriteria mathematical programming models. The results obtained show climate change effects on the crop portfolio. Further results suggest that climate change effects are not only economics and environmental, reducing the suitable area for crops, but also social as it causes loss of jobs in the agricultural sector.     

Global warming and livestock husbandry in Kenya: Impacts and adaptations

This paper examines the economic impact of climate change on livestock production in Kenya. We estimate a Ricardian model of net livestock incomes and further estimate the marginal impacts of climate change. We also simulate the impact of different climate scenarios on livestock incomes. The Ricardian results show that livestock production in Kenya is highly sensitive to climate change and that there is a non-linear relationship between climate change and livestock productivity. The estimated marginal impacts suggest modest gains from rising temperatures and losses from increased precipitation. The predictions from atmospheric ocean general circulation models suggest that livestock farmers in Kenya are likely to incur heavy losses from global warming. The highest and lowest losses are predicted from the Hadley Centre Coupled model (HADCM) and Parallel Climate Model (PCM) respectively, based on the Intergovernmental Panel on Climate Change A2 Special Report on Emissions Scenarios. The paper concludes that in the long term, climate change is likely to lead to increased poverty, vulnerability and loss of livelihoods. Several policy interventions are recommended to counter this impact.     

Economic Policy in the Face of Severe Tail Events

From time to time, something occurs which is outside the range of normal expectations. We will call these “tail events” in the sense that they are way out of the tail of a probability distribution. I consider the question of the implications of tail events for economic policy and climate‐change economics. This issue has been analyzed by Martin Weitzman who proposed a Dismal Theorem. The general idea is that, under limited conditions concerning the structure of uncertainty and risk aversion, society has an indefinitely large expected loss from high‐consequence, low‐probability events. Under such conditions, standard economic tools such as cost‐benefit analysis cannot be applied. The present study is intended to put the Dismal Theorem in context and examine the range of its relevance, with an application to catastrophic climate change. I conclude that tail events are sometimes of extreme importance, and we must be extremely careful to include them in situations of deep uncertainty. However, we conclude that no loaded gun of strong tail dominance has been uncovered to date.     

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.     

The impact of climate change skepticism on adaptation in a market economy

Climate change will increase the risk of temperature extremes. Induced innovation could offset some of this threat. This paper explores the demand and supply for climate adaptation innovation in a market economy. Such innovation attenuates the past relationship between the population death rate and extreme heat. Climate change induces this innovation because the rising temperatures increase demand for self protection products and for profit firms respond to these incentives. We then augment the model to introduce “climate skeptics”. Such skeptics reject the claim that the world’s average temperature is rising and thus do not increasingly demand adaptation products. In an economy featuring no government to enact optimal taxation, we quantify how rational agents are affected by the presence of climate skeptics.     

工业产业集聚对经济高质量发展的影响——以环境规制为调节变量的研究

基于外部性理论,利用2009—2017年中国省际面板数据并运用空间杜宾模型,从全样本和区域分样本两方面探讨了工业产业专业化集聚与相关多样性对经济高质量发展的影响。研究发现:中国省际经济高质量发展指数呈不断上升趋势,且存在空间相关性和空间溢出性,分别呈现出“一损俱损”“荣辱与共”“一荣俱荣”的城市群特征;工业产业专业化集聚和相关多样性对经济高质量发展都有影响,且环境规制在其中起到了调节作用,但对于不同的研究样本,作用效果存在差异;对于处在“一损俱损”“荣辱与共”阶段的城市群,应聚焦主要问题,通过发展主要方面,促进经济高质量发展并向“一荣俱荣”城市群转变。     

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.     

Basin impacts of irrigation water conservation policy

Climate change, uncertain future water supplies, growing population, and increased water demands continue to raise the importance of finding cost-effective water conservation measures. Irrigated agriculture is the world's largest water user, so governments, donor organizations, water suppliers, and farmers continue to look for measures that would produce more crop per drop. Despite the importance of promoting water conservation in agriculture, little work has been done that integrates hydrologic, economic, institutional, and policy dimensions of water conservation. This paper presents an integrated basin scale analysis of water conservation subsidies for irrigated agriculture. A dynamic, nonlinear programming model is developed and applied for the Upper Rio Grande Basin of Colorado, New Mexico, and Texas, USA. Several potential public subsidies of drip irrigation are analyzed for their economic and hydrologic impacts at both the farm and basin levels. Results indicate that water conservation subsidies for drip irrigation produce several effects. These include greater on-farm implementation of water-conserving technology, less water applied to crops, more water consumed by crops, increased farm income, greater crop production, more land irrigated, and increased total water-related economic benefits for the basin. Findings provide a framework for designing and implementing water conservation policies for irrigated agriculture.     

Effects of the Chinese arable land fallow system and land-use change on agricultural production and on the economy

This study focuses on economic effects of arable land fallow system and land-use change in China using a dynamic single-country, multi-regional computable general equilibrium model. Land supply is adjusted endogenously in our model. Land use in each of 31 provinces is tracked by a land-use change module, which is calibrated with satellite data. Our results reveal that the expansion of real output can be attributed to the increase in capital stock as a result of the growth of investment due to the imposition of the arable land fallow system in China. And the growth of investment is caused by the release of labor from agriculture The reduced supply of arable land in agricultural land contraction regions is partially offset by the increasing arable land in agricultural land expansion regions. Rural households benefit more than urban households from the arable land fallow policy due to relatively higher income and lower rural CPI.     

Why economic dynamics matter in assessing climate change damages: Illustration on extreme events

Extreme events are one of the main channels through which climate and socioeconomic systems interact, and it is likely that climate change will modify the probability distribution of the losses they generate. The long-term growth models used in climate change assessments, however, cannot capture the effects of such short-term shocks. To investigate this issue, a non-equilibrium dynamic model (NEDyM) is used to assess the macroeconomic consequences of extreme events. This exercise allowed us to define the economic amplification ratio, as the ratio of the overall production loss due to an event to its direct costs. This ratio could be used to improve the cost-benefit analysis of prevention measures. We found also that, unlike a Solow-like model, NEDyM exhibits a bifurcation in GDP losses: for each value of the capacity to fund reconstruction, GDP losses remain moderate if the intensity and frequency of extremes remain under a threshold value, beyond which GDP losses increase sharply. This bifurcation may partly explain why some poor countries that experience repeated natural disasters cannot develop. Applied to the specific issue of climate change, this model highlights the importance of short-term constraints in the assessment of long-term damages, and shows that changes in the distribution of extremes may entail significant GDP losses in absence of specific adaptation. It suggests, therefore, that to avoid inaccurately low assessments of damages, researchers must take into account the distribution of extremes instead of their average cost and make explicit assumptions on the organization of future economies.