Welfare‐at‐Risk and Extreme Dependency of Regional Wheat Yields: Implications of a Stochastic CGE Model

Stochastic computable general equilibrium (CGE) models have ignored regional correlations in agricultural yields, assuming random shocks to be independent between regions. This could lead to misinterpretation of simulation outputs which ignore extreme positive or negative harvests at the global scale. We develop a multi‐regional CGE model which allows for five types of interregional correlation between wheat yields to analyse the vulnerability of countries against fluctuating international markets, focusing on Value at Risk (VaR) and extreme dependency. We find that global welfare risks could be underestimated by up to 33% if significant interregional correlations in yield shocks are not taken into account. Egypt, Kazakhstan, Ukraine, the former Soviet Union and Northern Africa are particularly vulnerable to global volatilities in terms of economic welfare.     

中国北方苹果连阴雨灾害时空分布特征

[目的]苹果是一种经济林果,其品质和产量对果园效益和当地经济发展至关重要。连阴雨灾害是影响苹果品质和产量的主要灾害之一。通过分析1982—2018年苹果生长季连阴雨灾害时空分布特征,探讨连阴雨灾害对苹果生长发育的影响,以期为苹果生产布局、产业优化和果园防灾减灾提供指导。[方法]文章基于1982—2018年中国北方地区186个站点的气象数据和苹果发育期数据,选取始花—幼果期、着色—成熟期和采收期3个生育阶段,结合连阴雨灾害指标,分析苹果不同生育阶段连阴雨灾害时空变化特征。[结果]空间上,苹果各生育阶段连阴雨灾害主要发生在东南区域,着色—成熟期和采收期是灾害发生的主要生育阶段,连阴雨过程均降水量、过程均天数、频率和年均过程次数均呈现由东南至西北逐渐减小的趋势;时间上,1982—2018年连阴雨过程均降水量、连阴雨发生总次数和灾害强度呈现年际间波动。对比3个生育阶段历年连阴雨灾害统计情况可知,多数年份着色—成熟期和采收期连阴雨灾害发生总次数、过程均降水量和灾害强度均高于始花—幼果期,且着色—成熟期和采收期连阴雨灾害变化趋势基本一致。[结论] 1982—2018年中国北方苹果连阴雨灾害发生概率...     

The productivity impact of climate change: Evidence from Australia's Millennium drought

The economic impact of climate change has usually been estimated based on changes in average weather condition and is often measured in terms of immediate loss of output or profit. Yet little is known about the impact of extreme weather event, in particular its impact on productivity in the medium to long term. Using Australia's Millennium drought as a case of extreme weather event and applying the synthetic control method, we show that severe droughts occurred between 2002 and 2010 has brought down agricultural total factor productivity by about 18 percent in Australia over the period, contributing significantly to the country's long-term slowdown of agricultural total factor productivity growth. Our results highlight the significance of productivity impact of extreme weather events that has been overlooked when accessing the economic impact of climate change.     

Analysis of airport weather impact on on-time performance of arrival flights for the Brazilian domestic air transportation system

Air traffic operations are significantly impacted by weather conditions. These external factors may impose operational constraints and generate demand-capacity imbalances, leading to reduced on-time performance, additional airline costs and inconveniences to passengers. Efficient management of such disruptions requires an understanding of the main causes of flight delays towards increasing their predictability. In this study, we investigate the impacts of airport surface weather conditions on the likelihood of flight delays for the Brazilian domestic air transportation system. We use historical flight schedule, on-time performance and weather data and estimate a logit model to analyze how different meteorological variables at the airport of destination affect the probability of a delayed arrival. We obtain empirical evidence for the impacts of low ceiling and visibility conditions, precipitation and wind gusts on the likelihood of arrival delays for the set of Brazilian airports analyzed.     

New development: Flood events continue to raise issues of public sector accountability

Climate change scientists argue that there is a link between climate change and the frequency and severity of extreme weather events. The catastrophic consequences of these natural disasters on human life, agriculture and infrastructure calls into question the role and responsibility of governments in managing such events. Mixed messages are being communicated by governments to the public from one extreme advocating the provision of as much assistance as required to rebuild communities following an extreme weather event, to policies being developed encouraging communities to become more resilient. Seemingly, there is no contradiction in following both approaches, however, it is currently not clear the extent of responsibility and accountability for protecting its citizens versus the onus on the community to defend itself from natural disasters. This paper explores these themes from the perspective of local government in relation to the devastating floods that hit Victoria, Australia in 2010/11.     

Ethics and influences in tourist perceptions of climate change

Ethical decisions to visit disappearing destinations are self-serving and influences feed into self-interest. Data were collected from a sample of pre-, during- and post-visit tourists to Venice and Svalbard, using expressive techniques and scenarios using the Hunt–Vitell model to understand ethical decisions, and the constructive technique and collage to understand influences. The results show that travel decisions are driven by individual selfishness, and any threat to freedom (i.e. the right to travel) is underplayed. The preferred scenario for long-term benefit for planet and people is via short-term economic and social negative impacts on the destination's locals, rather than the tourists' own experience. Respondents believe that they are blameless for their purchasing habits as they lack perceived behavioural control, and instead corporations ought to be providing sustainable products as the norm and not sell products that harm. In the scenarios, where respondents express concern for the locals in a disappearing destination (i.e. if we do not visit, they will not benefit from our expenditure), individual selfishness to visit could be the driver, rather than an altruistic act to provide support. Theoretical and policy implications are discussed.     

简述提高地面气象测报质量的方法

地面测报工作作为气象测报工作基础中的基础,其测量质量的高低直接影响着气象测报工作的总体质量.作为气象测报工作人员,笔者对日常气象观测过程中几种常见的问题进行了简单的介绍,并着重对如何提高地面气象测报质量提出了几点建议.希望对我国地面气象测报工作的开展有所帮助,进而提高我国气象观测的总体水平.     

石家庄市灰霾天气特征分析及防控对策

通过研究石家庄市灰霾天气的现状及特征,分析了石家庄市灰霾天气形成原因,针对石家庄市的环境现状,提出了具有可操作性的防控对策。     

浅析高温天气下混凝土桩基浇筑施工的控制要点

本文以中铁六局集团有限公司府谷煤业铁路专用线黑泥池沟2#大桥为例,对高温天气环境下,水下混凝土浇筑桩基在施工过程中存在的问题作了简要论述,结合自身经验与相关文献,从已经遇到和可能遇到的方面提出了相应的解决方案,阐述了高温天气下混凝土施工的控制要点。