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1.
There is now substantial empirical evidence that climatic variability increases international migration, but relatively little is known about the mechanism driving the association and about adaptations that may reduce it. We use detailed data on migrants from Mexico to the U.S. to provide evidence in support of the hypothesis that drought induced migration from Mexico to the U.S. is mediated by agricultural income shocks. Migration rates increase in drought years, but only in Mexico’s drier regions, and the response is stronger in states and seasons in which agricultural production is also more sensitive to precipitation. Moreover, among the sample, only farmers display a significant increase in migration rates in drought years, and the effect is substantially weaker for households with access to irrigation. 相似文献
2.
Accurate records of basinwide Atlantic and U.S. landfalling hurricanes extend back to the mid 1940s and the turn of the century, respectively, as a result of aircraft reconnaissance and instrumented weather stations along the U.S. coasts. Such long-term records are not exceeded elsewhere in the tropics. The Atlantic hurricanes, U.S. landfalling hurricanes and U.S. normalized damage time series are examined for interannual trends and multidecadal variability. It is found that only weak linear trends can be ascribed to the hurricane activity and that multidecadal variability is more characteristic of the region. Various environmental factors including Caribbean sea level pressures and 200mb zonal winds, the stratospheric Quasi-Biennial Oscillation, the El Niño-Southern Oscillation, African West Sahel rainfall and Atlantic sea surface temperatures, are analyzed for interannual links to the Atlantic hurricane activity. All show significant, concurrent relationships to the frequency, intensity and duration of Atlantic hurricanes. Additionally, variations in the El Niño-Southern Oscillation are significantly linked to changes in U.S. tropical cyclone-caused damages. Finally, much of the multidecadal hurricane activity can be linked to the Atlantic Multidecadal Mode - an empirical orthogonal function pattern derived from a global sea surface temperature record. Such linkages may allow for prediction of Atlantic hurricane activity on a multidecadal basis. These results are placed into the context of climate change and natural hazards policy. 相似文献
3.
This article explores the role of risk perception in adaptation to stress through comparative case studies of coffee farmers’ responses to climatic and non-climatic stressors. We hypothesized that farmers associating these changes with high risk would be more likely to make adaptations than those who saw the events as part of normal variation. Nevertheless, we found that farmers who associated events with high risk were not more likely to engage in specific adaptations. Adaptive responses were more clearly associated with access to land than perception of risk, suggesting that adaptation is more a function of exogenous constraints on decision making than perception. 相似文献
5.
Summary Singular vectors (SVs) constructed from the adjoint model of the U.S. Naval Operational Global Atmosphere Prediction System
(NOGAPS) for three Atlantic hurricanes in 2004, Ivan, Jeanne and Karl, are examined to understand interactions between them
and a mid-latitude trough system. By optimizing the perturbation energy localized in a small region centered at the 48-hour
projected position of a tropical cyclone, the initial time singular vector represents the sensitive region to the final state
within the specified region for a specified optimization period. For hurricane Ivan, the SV analysis reveals the merging of
a shortwave mid-latitude trough and Ivan to form a new trough system. This new trough system impacted the evolution of hurricane
Jeanne in subsequent time through the upstream flow of the trough that moved toward Jeanne. This is consistent with previous
studies on the sensitivity of tropical cyclone prediction using SV diagnostics. The SV associated with Jeanne at later stage
shows that Jeanne influenced the third hurricane Karl through the trough system as Karl went through extratropical transition
and became part of the trough. This effect is magnified when the SV is computed using the moist adjoint system containing
large scale precipitation. Detailed diagnostics of the SVs for individual components at different levels show that the sensitivity
associated with the trough is very similar for those optimized for Jeanne and Karl, respectively, thus providing evidence
that the mid-latitude trough impacted Jeanne and Karl at the same time. This study demonstrates the capability of singular
vector in diagnosing complicated interactions among a mid-latitude trough and three co-existing tropical cyclones. 相似文献
7.
Abstract The failure of Los Angeles' RECLAIM emission trading market in the summer of 2000 uncovers important issues that have direct relevance for the various systems now emerging for exchanging greenhouse gas credits. Two primary causes for the breakdown of RECLAIM are apparent. On the one hand, RECLAIM did not succeed because of a series of unpredictable events that included manipulation of the market by brokers and the California energy shortage. On the other hand, several potentially foreseeable program design flaws contributed to the failure. This study examines the structure of RECLAIM and concludes that there was sufficient resilience to endure the two unexpected crises. However, the problematic program design features created a market that was fatally flawed and, regardless of impinging circumstances, was ultimately bound to collapse. We also investigate the status of the rapidly developing international greenhouse gas market and identify several lessons from the RECLAIM experience: the need for a holistic approach to market design that includes the role of a bank, the interface with project-based credits, the similarities of the industries enrolled in the program, and need to carefully consider how to handle the problems caused by the end of the trading period. 相似文献
8.
Mexico is relatively advanced in its preparation for international policy on Reduced Emissions from Deforestation and forest Degradation (REDD+) and has many of the pre-conditions needed to support a community approach in the implementation of a national REDD+ programme, particularly as regards tenure of forests and experience with community forest management and PES schemes, although these conditions do not pertain everywhere. One critical issue that is yet to be resolved concerns rights to carbon credits and distribution of the financial benefits flowing from REDD+. We demonstrate that attribution of carbon credits from reduced deforestation and degradation at the community level is virtually impossible from a technical viewpoint, since these credits are counterfactual. Payments based on assessment of performance of each community in terms of such reductions would moreover be inequitable and inefficient. Flat rate payments in return for agreed improvements in management are likely to be more motivating and much easier to administer. However, increases in carbon stock (forest enhancement) can be physically measured on site, and could be more easily attributed to each individual community. We therefore propose a system in which reduced deforestation and degradation are considered environmental services, with credits accruing to national government. The financial value of the credits may be used to finance flat rate payments to communities who agree to implement improved management. On the other hand, credits for forest enhancement, which reflect measurable increases in carbon in the communities’ trees, would be considered environmental goods. These should be considered the direct property of the owners of the forest (in the same sense as wood or poles) and it would be possible for communities to sell these credits themselves. We acknowledge however that many other problems face implementation of REDD+ in Mexico, and provide a number of important examples. 相似文献
9.
An atmospheric general circulation model, the NCAR CCM, has been used to investigate the possible effects that reduced Gulf of Mexico sea surface temperatures (SST) could have on regional and hemispheric climates. 18O records and terrestrial evidence indicate at least two major glacial meltwater discharges into the Gulf of Mexico subsequent to the last glacial maximum. It is probable that these discharges reduced Gulf of Mexico SST. We have conducted three numerical experiments, with imposed gulf-wide SST coolings of 3°C, 6°C, and 12°C, and find in all three experiments significant reductions in the North Atlantic storm-track intensity, along with a strong decrease in transient eddy water vapor transport out of the Gulf of Mexico. Surface pressures are higher over the North Atlantic, indicating a reduction of the climatological Icelandic low. The region is generally cooler and drier, with a reduction in precipitation that agrees well with evidence from Greenland ice cores. Other statistically significant changes occur across the Northern Hemisphere, but vary between the three experiments. In particular, warmer, wetter conditions are found over Europe for both the 6°C and 12°C SST reductions, but cooler conditions are found for the 3°C reduction. This indicates a dependence, in both the sign and magnitude of the model response, on the magnitude of the imposed SST anomaly. The results suggest that the present-day North Atlantic storm track is dependent on warm Gulf of Mexico SST for much of its intensity. They also suggest that meltwater-induced coolings may help account, in part, for some of the climatic oscillations that occurred during the last glacial/interglacial transition. 相似文献
10.
The recent Mexican government study, The Economics of Climate Change in Mexico (ECCM), which has largely influenced Mexico's stance on climate change issues and international negotiations, is critically reviewed. Whilst the importance of such government-supported national studies as a first attempt to provide estimates on the anticipated costs of climate change is recognized, there is scope to strengthen the underlying analysis. It is argued that some of the key policy recommendations of ECCM are weakly supported by its analysis, that it has some methodological weaknesses, and that there are inconsistencies with the approach adopted in the Stern Review. Furthermore, it is likely that the estimated costs severely under-represent future climate change damages in the case of Mexico, which could deter drastic mitigation and adaptation efforts. New estimates of the costs of climate change are presented based on the impact functions of two integrated assessment models. Policy relevanceDue to its large influence in building a regional view of what climate change could imply for Latin America, the analysis of the ECCM highlights the need to strengthen the analysis of national climate documents to ensure they properly support national/regional policy making. The academic evaluation of national climate change documents is a necessary prerequisite for the development of sound climate policy. 相似文献
11.
Governmental climate change mitigation targets are typically developed with the aid of forecasts of greenhouse-gas (GHG) emissions. The robustness and credibility of such forecasts depends, among other issues, on the extent to which forecasting approaches can reflect prevailing uncertainties. We apply a transparent and replicable method to quantify the uncertainty associated with projections of gross domestic product growth rates for Mexico, a key driver of GHG emissions in the country. We use those projections to produce probabilistic forecasts of GHG emissions for Mexico. We contrast our probabilistic forecasts with Mexico’s governmental deterministic forecasts. We show that, because they fail to reflect such key uncertainty, deterministic forecasts are ill-suited for use in target-setting processes. We argue that (i) guidelines should be agreed upon, to ensure that governmental forecasts meet certain minimum transparency and quality standards, and (ii) governments should be held accountable for the appropriateness of the forecasting approach applied to prepare governmental forecasts, especially when those forecasts are used to derive climate change mitigation targets. POLICY INSIGHTS No minimum transparency and quality standards exist to guide the development of GHG emission scenario forecasts, not even when these forecasts are used to set national climate change mitigation targets. No accountability mechanisms appear to be in place at the national level to ensure that national governments rely on scientifically sound processes to develop GHG emission scenarios. Using probabilistic forecasts to underpin emission reduction targets represents a scientifically sound option for reflecting in the target the uncertainty to which those forecasts are subject, thus increasing the validity of the target. Setting up minimum transparency and quality standards, and holding governments accountable for their choice of forecasting methods could lead to more robust emission reduction targets nationally and, by extension, internationally. 相似文献
12.
基于国际碳市场建设的初始决策环境,从政治诉求、决策环境、经济基础、市场根基等4个维度的32个子指标构建了碳市场建立背景与条件指标体系,据此深入挖掘了欧盟碳排放权交易体系(EU ETS)、美国区域温室气体减排行动(RGGI)、美国西部行动倡议(WCI)等国际典型碳市场建立的背景与基础条件,并归纳出各国建立不同类型碳市场的必要条件,进而判断中国建立各类碳市场所具备的条件和不足之处。研究发现:跨界联盟型碳市场建立通常具备经济联系紧密、单个地区减排成本过高和地理位置临近等3个要点;国家型碳市场建立通常考虑到了国家强制减排责任、能源结构转型需求强烈和稳固的国家立法保障等方面;地区型碳市场的建立需满足地区减排诉求强烈与国家层面排放权立法缺失等条件;行业型碳市场建立的基础条件则包括温室气体排放集中度高、行业竞争力保护、重点行业排放需求增长和行业排放数据基础稳固等4个特征。当前,中国碳市场应重点考虑行业型与跨界联盟型碳市场并行的建设模式,进一步完善碳市场监管法律体系,加快各省市排放数据清单制作,加强地方碳市场能力建设培训,尽快完善国家型碳市场建立的基本条件,进而实现温室气体减排与产业结构升级的双重目标。 相似文献
13.
The understanding of historic hydroclimatic variability is basic for planning proper management of limited water resources
in northeastern Mexico. The objective of this study was to develop a network of tree-ring chronologies to reconstruct hydroclimate
variability in northeastern Mexico and to analyze the influence of large-scale circulation patterns, such as ENSO. Precipitation
sensitive tree-ring chronologies of Douglas-fir were developed in mountain ranges of the Sierra Madre Oriental and used to
produce winter-spring precipitation reconstructions for central and southern Nuevo Leon, and southeastern Coahuila. The seasonal
winter-spring precipitation reconstructions are 342 years long (1659–2001) for Saltillo, Coahuila and 602 years long (1400–2002)
for central and southern Nuevo Leon. Both reconstructions show droughts in the 1810s, 1870s, 1890s, 1910s, and 1970s, and
wet periods in the 1770s, 1930s, 1960s, and 1980s. Prior to 1800s the reconstructions are less similar. The impact of ENSO
in northeastern Mexico (as measured by the Tropical Rainfall Index) indicated long-term instability of the Pacific equatorial
teleconnection. Atmospheric circulation systems coming from higher latitudes (cold fronts or `nortes’) and others developed
in the Gulf of Mexico (tropical storms, hurricanes) also influence the climatic conditions characterizing this region. The
recent development of new and longer tree-ring chronologies for the region will contribute to a better understanding of the
interannual and multidecadal climatic variability of northeastern Mexico. 相似文献
15.
Our current understanding of the ability of climate models to provide insight into the possible impacts of the enhanced greenhouse effect on the climatology of tropical cyclones and extreme rainfall events is reviewed. At present, because of the insufficient resolution of climate models and their generally crude representation of sub-gridscale and convective processes, little confidence can be placed in any definite predictions of such effects, although a tendency for more heavy rainfall events seems likely, and a modest increase in tropical cyclone intensities is possible. In the view of the authors, it would be unwise to exclude substantial local changes in the climatologies of these phenomena, especially at a regional (sub-continental) scale. 相似文献
16.
The article explores the strategies employed by smallholder farmers in Mexico to cope with the affects of climatic variability, and how seasonal climate forecasts may assist these farmers in mitigating climatic risk. Recognizing that the decisions of smallholder farmers are intricately tied to the political-economic circumstances in which they operate, the article discusses how agricultural policy in Mexico affects the vulnerability of small-scale producers and may inhibit their ability to use climatic forecasts to their advantage. The article first reviews the literature on smallholder adaptation in Mexico, and discusses briefly policy and institutional issues affecting adaptation at the farm-level. Using the case of small-scale maize producers in Tlaxcala, Mexico, as an illustration, the article then argues that political-economic uncertainty outweighs climatic variability as a determinant of the production strategies of small-scale producers. In these circumstances, the farmers are unlikely to use new seasonal climate forecasts. 相似文献
17.
Analysis and enhancement of “coupling” of social-ecological systems (SES) has emerged as a leading theme in sustainability studies. However, as an analytical concept that can support empirical research, coupling has not been adequately developed. This study synthesizes concepts from environmental sociology and ecological sciences to derive three criteria to assess adaptive coupling of an SES: prevention orientation, spatial targeting and temporal targeting. We apply our criteria to the case of nitrogen pollution from agriculture in the Mississippi River Basin (MRB) and resulting hypoxia in the Gulf of Mexico. We analyzed the federal agricultural research and development portfolio to assess the character of investments in knowledge creation and how patterns of investment have changed over time. While superficial assessment of the data suggests that public spending on nitrogen relevant research constitutes a substantive response to the problem of Gulf hypoxia, disaggregating the data highlights an ineffectual response. Specifically, we find that spatial and temporal targeting of investment of socioeconomic resources in the MRB is poorly aligned with the nature of ecological risks confronting the region. In addition to this policy relevant result, our study highlights the importance of geographically referenced data and attention to relevant scales of analysis. Further, the paper demonstrates opportunities to advance concepts and empirical understanding of social-ecological coupling through interdisciplinary research on interfaces that mediate interactions in SES, for example publicly funded research aimed at agricultural practice and environmental conservation in the MRB. 相似文献
19.
Because of large economic and environmental asymmetries among world regions and the incentive to free ride, an international climate regime with broad participation is hard to reach. Most of the proposed regimes are based on an allocation of emissions rights that is perceived as fair. Yet, there are also arguments to focus more on the actual welfare implications of different regimes and to focus on a ‘fair’ distribution of resulting costs. In this article, the computable general equilibrium model DART is used to analyse the driving forces of welfare implications in different scenarios in line with the 2?°C target. These include two regimes that are often presumed to be ‘fair’, namely a harmonized international carbon tax and a cap and trade system based on the convergence of per capita emissions rights, and also an ‘equal loss’ scenario where welfare losses relative to a business-as-usual scenario are equal for all major world regions. The main finding is that indirect energy market effects are a major driver of welfare effects and that the ‘equal loss’ scenario would thus require large transfer payments to energy exporters to compensate for welfare losses from lower world energy demand and prices. Policy relevanceA successful future climate regime requires ‘fair’ burden sharing. Many proposed regimes start from ethical considerations to derive an allocation of emissions reduction requirements or emissions allowances within an international emissions trading scheme. Yet, countries also consider the expected economic costs of a regime that are also driven by other factors besides allowance allocation. Indeed, in simplified lab experiments, successful groups are characterized by sharing costs proportional to wealth. This article shows that the major drivers of welfare effects are reduced demand for fossil energy and reduced fossil fuel prices, which implies that (1) what is often presumed to be a fair allocation of emissions allowances within an international emissions trading scheme leads to a very uneven distribution of economic costs and (2) aiming for equal relative losses for all regions requires large compensation to fossil fuel exporters, as argued, for example, by the Organization of Petroleum Exporting Countries (OPEC). 相似文献
20.
There is a substantial literature on optimal emissions trading system (ETS) designs, but relatively little on how organized political interests affect the design and operation of these economic instruments. This article looks systematically at the political economy of the diffusion of ETS designs and explores the implications for carbon-market linking. Contrary to expectations of convergence – as has been observed in many areas where economic policy diffuses across markets – we found substantial divergence in the design and implementation of ETS across the nine systems examined. The architects of these different systems are aware of other designs, but they have purposely adjusted designs to reflect local political and administrative goals. Divergence has sobering implications for visions of ubiquitous linkages and the emergence of a global carbon market that, to date, have been predicated on the assumption that designs would converge. More such ‘real world’ political economy analysis is needed to understand how political forces, mainly within countries, act as strong intervening variables that affect instrument design, implementation and effectiveness. Key policy insights Our finding of design divergence indicates that policy efforts aimed at achieving integrated international markets are unlikely to be successful. Visions of carbon market linkage will need to confront the reality that there are well-organized political coalitions, anchored in the status quo, that prefer divergence. In linking ETS, policy-makers should devote more attention to preventing excessive capital flows that can undermine political support for linkage, while also creating incentives for convergence in trading rules over time. 相似文献
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