世界経済・社会統計 = World development indicators

Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

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Climate Change 2007: The Physical Science Basis.

Impatti, adattamento e vulnerabilita Le cause e le responsabilita dei cambiamenti climatici sono state trattate sul numero di ottobre della rivista Cda. Approfondiamo l’argomento presentando il documento: “Cambiamenti climatici 2007: impatti, adattamento e vulnerabilita” votato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamenti Climatici (Intergovernmental Panel on Climate Change). Si tratta del secondo di tre documenti che compongono il quarto rapporto sui cambiamenti climatici.

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Climate Change 2007: Impacts, Adaptation and Vulnerability.

Efforts to anticipate how climate change will affect future food availability can benefit from understanding the impacts of changes to date. We found that in the cropping regions and growing seasons of most countries, with the important exception of the United States, temperature trends from 1980 to 2008 exceeded one standard deviation of historic year-to-year variability. Models that link yields of the four largest commodity crops to weather indicate that global maize and wheat production declined by 3.8 and 5.5%, respectively, relative to a counterfactual without climate trends. For soybeans and rice, winners and losers largely balanced out. Climate trends were large enough in some countries to offset a significant portion of the increases in average yields that arose from technology, carbon dioxide fertilization, and other factors.

https://science.sciencemag.org/content/sci/early/2011/05/04/science.1204531.full.pdf

Climate Trends and Global Crop Production Since 1980

The talk with present the key results of the IPCC Working Group III 5th assessment report. Concluding four years of intense scientific collaboration by hundreds of authors from around the world, the report responds to the request of the world's governments for a comprehensive, objective and policy neutral assessment of the current scientific knowledge on mitigating climate change. The report has been extensively reviewed by experts and governments to ensure quality and comprehensiveness.

Climate change 2014 - Mitigation of climate change

Since 1970, transportation, power generation, and manufacturing have dramatically transformed as air pollutant emissions have fallen significantly. To evaluate the causal impacts of the Clean Air Act on these changes, we synthesize and review retrospective analyses of air quality regulations. The geographic heterogeneity in regulatory stringency common to many regulations has important implications for emissions, public health, compliance costs, and employment. Cap-and-trade programs have delivered greater emission reductions at lower cost than conventional regulatory mandates, but policy practice has fallen short of the cost-effective ideal. Implementing regulations in imperfectly competitive markets have also influenced the Clean Air Act’s benefits and costs.

Looking Back at Fifty Years of the Clean Air Act

In this chapter we discuss the economics of climate change. We begin with a discussion of economic considerations that are important to take into account when designing and evaluating climate policy, including cost effectiveness and efficiency. We then discuss specific policies at the state, national, and international level in light of these economic considerations.  We have several recommendations for the path forward for climate policy. First, the goal of climate policy should be to reduce the damages caused by greenhouse gases. In addition to mitigation policy to reduce greenhouse gas concentrations in the atmosphere, one can also reduce the damages causes by greenhouse gases by adaptation measures that reduce our vulnerability to climate change impacts.  Second, policy-makers should use incentive- (or market-) based instruments as opposed to command and control policies (including quantity-based mandates) whenever possible. Whenever unpriced emissions are the sole market failure, incentive-based instruments such as a carbon tax or cap and trade program are more likely to achieve the social optimum and maximize social net benefits [1, 2]. Lin and Prince [3] calculate that the optimal gasoline tax for the state of California is $1.37 per gallon.  Our third recommendation is to address the risk of emissions leakage, which arises when only one jurisdiction (e.g., California) imposes climate policy, but not the entire world. One way to reduce emissions leakage is to use the strategic distribution of emissions allowances to local producers. This method, known as “output-based allocation” or benchmarking, effectively subsidizes local producers and at least partially offsets the increase in their costs caused by an emissions cap [4]. Importantly, only local production is eligible for an allocation of valuable allowances, providing a counterweight to the incentive for emission leakage. Our fourth recommendation is that if they are used instead of incentive-based instruments, quantity-based mandates such as the federal Renewable Fuel Standard, California’s Low Carbon Fuel Standard, renewable portfolio standards, and the Clean Power Plan should be combined with a cost containment mechanism. The findings of Lade, Lin Lawell and Smith [5] suggest that pure quantity-based mechanisms leave policies susceptible to large increases in compliance costs, particularly in the presence of capacity or production constraints that are inherent in energy markets. Given the experiences with the federal RFS2 in 2013, anticipating and designing climate policies in a way that can contain compliance costs is imperative.  Our fifth recommendation is that for international leverage, we should develop a climate club backed by border tax adjustments to non-participants. University of California at Berkeley Professor Larry S. Karp has been proposing an agreement between the top 10 emitters as an alternative to the UN framework [6]. Without international leverage or cooperation, unilateral climate policies, such as California’s AB 32 or the American Clean Energy and Security Act, are not only unlikely to fully combat climate change, but can also have other detrimental effects such as the reduction of economic competitiveness and the possible displacement of jobs from the U.S. to countries without carbon pricing [7]. Our final, and main, recommendation is that, as University of California at Berkeley Professor Severin Borenstein points out, California should focus on solving the problem of global climate change. The primary goal of California climate policy should be to invent and develop the technologies that can replace fossil fuels, allowing the poorer nations of the world – where most of the world’s population lives – to achieve low-carbon economic growth [8].

Chapter 4. Economic Considerations: Cost-Effective and Efficient Climate Policies

The impact of climate change on food production remains uncertain, particularly in the tropics. Research that exploits the results of historical crop trials indicates that Africa's maize crop could be at risk of significant yield losses.

Agriculture: Weather dilemma for African maize

Labor Trajectories in California's Produce Industry Meeting a Growing Demand for Food and Fuel in a Sustainable Manner. Water and Jobs: The Role of Irrigation Water Deliveries on Agricultural Employment.

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Agricultural and Resource Economics Update - eScholarship

Since 2006, China has experienced an unprecedented expansion of its wind and solar power generation capacity and associated manufacturing industries. This rapid growth was supported by larg...

Maximilian Auffhammer

Papers

Looking Back at Fifty Years of the Clean Air Act

Chapter 4. Economic Considerations: Cost-Effective and Efficient Climate Policies

Agriculture: Weather dilemma for African maize

Agricultural and Resource Economics Update - eScholarship

Renewable Electricity Development in China: Policies, Performance, and Challenges