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1.
Climate change impacts on global agriculture   总被引:1,自引:0,他引:1  
Based on predicted changes in the magnitude and distribution of global precipitation, temperature and river flow under the IPCC SRES A1B and A2 scenarios, this study assesses the potential impacts of climate change and CO2 fertilization on global agriculture. The analysis uses the new version of the GTAP-W model, which distinguishes between rainfed and irrigated agriculture and implements water as an explicit factor of production for irrigated agriculture. Future climate change is likely to modify regional water endowments and soil moisture. As a consequence, the distribution of harvested land will change, modifying production and international trade patterns. The results suggest that a partial analysis of the main factors through which climate change will affect agricultural productivity provide a false appreciation of the nature of changes likely to occur. Our results show that global food production, welfare and GDP fall in the two time periods and SRES scenarios. Higher food prices are expected. No matter which SRES scenario is preferred, we find that the expected losses in welfare are significant. These losses are slightly larger under the SRES A2 scenario for the 2020s and under the SRES A1B scenario for the 2050s. The results show that national welfare is influenced both by regional climate change and climate-induced changes in competitiveness.  相似文献   

2.
Residuals from agricultural pesticides threaten the environment and human health. Climate change alters these externalities because it affects pest pressure and pesticide application rates. This study examines damages from pesticide externalities in US agriculture under different climate projections and the effects of alternative regulations. We find divergent impacts of externality regulation and climate change on agricultural production in the US. A Pigovian tax on pesticide externalities generally increases crop production cost, but farm revenue improves because of increased commodity prices. Climate change generally decreases US farm revenue because production increases and prices fall. Results also show a heterogeneous effect of climate change on pest management intensities across major crops.  相似文献   

3.
This study estimates the relationship between farm level net-revenue and climate variables in India using cross-sectional evidence. Using the observed reactions of farmers, the study seeks to understand how they have adapted to different climatic conditions across India. District level data is used for the analysis. The study also explores the influence of annual weather and crop prices on the climate response function. The estimated climate response function is used to assess the possible impacts of a ‘best-guess’ climate change scenario on Indian agriculture.  相似文献   

4.
We examined the impacts on U.S. agriculture of transient climate change assimulated by 2 global general circulation models focusing on the decades ofthe 2030s and 2090s. We examined historical shifts in the location of cropsand trends in the variability of U.S. average crop yields, finding thatnon-climatic forces have likely dominated the north and westward movement ofcrops and the trends in yield variability. For the simulated future climateswe considered impacts on crops, grazing and pasture, livestock, pesticide use,irrigation water supply and demand, and the sensitivity to international tradeassumptions, finding that the aggregate of these effects were positive for theU.S. consumer but negative, due to declining crop prices, for producers. Weexamined the effects of potential changes in El Niño/SouthernOscillation (ENSO) and impacts on yield variability of changes in mean climateconditions. Increased losses occurred with ENSO intensity and frequencyincreases that could not be completely offset even if the events could beperfectly forecasted. Effects on yield variability of changes in meantemperatures were mixed. We also considered case study interactions ofclimate, agriculture, and the environment focusing on climate effects onnutrient loading to the Chesapeake Bay and groundwater depletion of theEdward's Aquifer that provides water for municipalities and agriculture to theSan Antonio, Texas area. While only case studies, these results suggestenvironmental targets such as pumping limits and changes in farm practices tolimit nutrient run-off would need to be tightened if current environmentalgoals were to be achieved under the climate scenarios we examined  相似文献   

5.
The appropriate level of spatial resolution for climate scenarios is a key uncertainty in climate impact studies and regional integrated assessments. To the extent that such uncertainty may affect the magnitude of economic estimates of climate change, it has implications for the public policy debates concerning the efficiency of CO2 control options. In this article, we investigate the effects that different climate scenario resolutions have on economic estimates of the impacts of future climate changeon agriculture in the United States. These results are derived via a set of procedures and an analytical model that has been used previously in climate change assessments. The results demonstrate that the spatial scale of climate scenarios affects the estimates of both regional changes in crop yields and the economic impact on the agricultural sector as a whole. An assessment based on the finer scale climatological information consistently yielded a less favorable assessment of the implications of climate change. Regional indicators of economic activity were of opposite sign in some regions, based on the scenario scale. Such differences in economic magnitudes or signs are potentially important in examining whether past climate change assessments may misstate the economic consequences of such changes. The results reported here suggest that refinement of the spatial scale of scenarios should be carefully considered in future impacts research.  相似文献   

6.
The poverty implications of climate-induced crop yield changes by 2030   总被引:1,自引:0,他引:1  
Accumulating evidence suggests that agricultural production could be greatly affected by climate change, but there remains little quantitative understanding of how these agricultural impacts would affect economic livelihoods in poor countries. Here we consider three scenarios of agricultural impacts of climate change by 2030 (impacts resulting in low, medium, or high productivity) and evaluate the resulting changes in global commodity prices, national economic welfare, and the incidence of poverty in a set of 15 developing countries. Although the small price changes under the medium scenario are consistent with previous findings, we find the potential for much larger food price changes than reported in recent studies which have largely focused on the most likely outcomes. In our low-productivity scenario, prices for major staples rise 10–60% by 2030. The poverty impacts of these price changes depend as much on where impoverished households earn their income as on the agricultural impacts themselves, with poverty rates in some non-agricultural household groups rising by 20–50% in parts of Africa and Asia under these price changes, and falling by significant amounts for agriculture-specialized households elsewhere in Asia and Latin America. The potential for such large distributional effects within and across countries emphasizes the importance of looking beyond central case climate shocks and beyond a simple focus on yields – or highly aggregated poverty impacts.  相似文献   

7.
To better understand the implications of anthropogenic climate change for three major Mid-Atlantic estuaries (the Chesapeake Bay, the Delaware Bay, and the Hudson River Estuary), we analyzed the regional output of seven global climate models. The simulation given by the average of the models was generally superior to individual models, which differed dramatically in their ability to simulate twentieth-century climate. The model average had little bias in its mean temperature and precipitation and, except in the Lower Chesapeake Watershed, was able to capture the twentieth-century temperature trend. Weaknesses in the model average were too much seasonality in temperature and precipitation, a shift in precipitation’s summer maximum to spring and winter minimum to fall, interannual variability that was too high in temperature and too low in precipitation, and inability to capture the twentieth-century precipitation increase. There is some evidence that model deficiencies are related to land surface parameterizations. All models warmed over the twenty-first century under the six greenhouse gas scenarios considered, with an increase of 4.7 ± 2.0°C (model mean ± 1 standard deviation) for the A2 scenario (a medium-high emission scenario) over the Chesapeake Bay Watershed by 2070–2099. Precipitation projections had much weaker consensus, with a corresponding increase of 3 ± 12% for the A2 scenario, but in winter there was a more consistent increase of 8 ± 7%. The projected climate averaged over the four best-performing models was significantly cooler and wetter than the projected seven-model-average climate. Precipitation projections were within the range of interannual variability but temperature projections were not. The implied research needs are for improvements in precipitation projections and a better understanding of the impacts of warming on streamflow and estuarine ecology and biogeochemistry.  相似文献   

8.
Climate change will affect agricultural production by subsistence farms in crop centers of origin, where landraces are conserved in situ. Various strategies for adaptation to climate change have been proposed. In this paper we examine the prospects of what we call the ‘transgenic adaptation strategy’, i.e. the appeal to use transgenic seeds to adapt to climate change, through the lens of smallholder maize farming in Mexico. Landraces are the bedrock of maize production in Mexico. We consider how maize farmers may respond to climate change and the effects of those responses on crop diversity. In this paper, we argue that the promotion of the transgenic adaptation strategy is problematic for biological and social reasons. Smallholder livelihoods in southern Mexico could suffer a disproportionate negative impact if transgenic technology is privileged as a response to climate change. Agroecological and evolutionary approaches to addressing the effects of climate change on smallholder agriculture provides an alternative adaptive strategy.  相似文献   

9.
Climate volatility could change in the future, with important implications for agricultural productivity. For Tanzania, where food production and prices are sensitive to climate, changes in climate volatility could have severe implications for poverty. This study uses climate model projections, statistical crop models, and general equilibrium economic simulations to determine how the vulnerability of Tanzania's population to impoverishment by climate variability could change between the late 20th Century and the early 21st Century. Under current climate volatility, there is potential for a range of possible poverty outcomes, although in the most extreme of circumstances, poverty could increase by as many as 650,000 people due to an extreme interannual decline in grain yield. However, scenarios of future climate from multiple climate models indicate no consensus on future changes in temperature or rainfall volatility, so that either an increase or decrease is plausible. Scenarios with the largest increases in climate volatility are projected to render Tanzanians increasingly vulnerable to poverty through impacts on staple grains production in agriculture, with as many as 90,000 additional people entering poverty on average. Under the scenario where precipitation volatility decreases, poverty vulnerability decreases, highlighting the possibility of climate changes that oppose the ensemble mean, leading to poverty impacts of opposite sign. The results suggest that evaluating potential changes in volatility and not just the mean climate state may be important for analyzing the poverty implications of climate change.  相似文献   

10.
The Western Australian wheat-belt has experienced more rainfall decline than any other wheat-cropping region in Australia. Future climate change scenarios suggest that the Western Australian wheat-belt is likely to see greater future reductions in rainfall than other regions, together with a further increase in temperatures. While these changes appear adverse for water-limited rain-fed agriculture, a close analysis of the changes and their impacts reveals a more complex story. Twentieth century changes in rainfall, temperature and atmospheric CO2 concentration have had little or no overall impact on wheat yields. Changes in agricultural technology and farming systems have had much larger impacts. Contrary to some claims, there is no scientific or economic justification for any immediate actions by farmers to adapt to long-term climate change in the Western Australian wheat-belt, beyond normal responses to short-term variations in weather. Rather than promoting current change, the most important policy response is research and development to enable farmers to facilitate future adaptation to climate change. Research priorities are proposed.  相似文献   

11.
Bangladesh, the sixth largest rice producer in the world, has been identified as high risk from the effects of climate change. Many of the adverse impacts of climate change such as land inundation and changes in weather patterns and CO2 levels will impact the agricultural sector. This study develops a partial-equilibrium multi-regional farm household model of Bangladesh rice and non-rice agricultural markets to quantify the impacts of climate change on consumption, production, prices, and farmers’ welfare. The model is calibrated to the Bangladesh rice market using Household Income and Expenditure Survey data. The model is simulated to analyze the impact of land reduction and productivity decline resulting from climate change. The results show that the decline in production in the coastal and northern regions offsets the production increase in the central and eastern regions, and the simulation predicts that total rice production for Bangladesh falls by about 2%. As total rice consumption falls and imports rise, the net effect leads to a rise in the rice price by 5.71% and a decline in farmers’ welfare. Sensitivity analysis shows that more- (less-) effective abatement technology could play a key role in mitigating (exacerbating) the price and welfare effects. The model predicts that many farmers in regions directly impacted by climate change could leave farming in search of off-farm work. Thus, the government can ease this transition by promoting urban development to provide more job options and technical training for farmers.  相似文献   

12.
The climate of the 1930s was used as an analog of the climate that might occur in Missouri, Iowa, Nebraska and Kansas (the MINK region) as a consequence of global warming. The analog climate was imposed on the agriculture of the region under technological and economic conditions prevailing in 1984/87 and again under a scenario of conditions that might prevail in 2030. The EPIC model of Williamset al. (1984), modified to allow consideration of the yield enhancing effects of CO2 enrichment, was used to evaluate the impacts of the analog climate on the productivity and water use of some 50 representative farm enterprises. Before farm level adjustments and adaptations to the changed climate, and absent CO2 enrichment (from 350 to 450 ppm), production of corn, sorghum and soybeans was depressed by the analog climate in about the same percent under both current and 2030 conditions. Production of dryland wheat was unaffected. Irrigated wheat production actually increased. Farm level adjustments using low-cost currently available technologies, combined with CO2 enrichment, eliminated about 80% of the negative impact of the analog climate on 1984/87 baseline crop production. The same farm level adjustments, plus new technologies developed in response to the analog climate, when combined with CO2 enrichment, converted the negative impact on 2030 crop production to a small increase. The analog climate would have little direct effect on animal production in MINK. The effect, if any, would be by way of the impact on production of feed-grains and soybeans. Since this impact would be small after on-farm adjustments and CO2 enrichment, animal production in MINK would be little affected by the analog climate.  相似文献   

13.
基于在云南省西部保山地区开展的入户问卷调查和关键信息人访谈,探讨在发生旱灾,大量农民外出务工以弥补旱灾给家庭和农业生产带来的损失这一特定背景下,对比外出务工农户和非外出务工农户在收入来源、应对旱灾措施和家庭收入分配上的差异,分析外出务工对农民适应气候变化能力带来的影响。结果表明:外出务工收入给留守家庭的气候变化适应能力带来了积极的影响;另外一方面,大量青壮年劳动力的外出让经济结构仍然以农业为主的村庄出现劳动力缺乏、农业发展后续动力不足等潜在问题。建议在未来针对外出务工人口开展的职业培训中增加诸如家庭财务管理、气候变化等相关内容来加强农村地区和农民的气候变化适应能力,建议政府推广气候智能农业,采取本地化/本土化的适应措施。  相似文献   

14.
气候变化对中国农业生产的影响研究进展   总被引:54,自引:6,他引:48       下载免费PDF全文
气候变化已成为当今科学界、各国政府和社会公众普遍关注的环境问题之一,气候变化可能对生态系统和社会经济产生灾难性影响,农业是受气候变化影响最直接的脆弱行业。因此,气候变化对农业生产的影响研究一直是气候变化研究领域中的热点问题之一。该文系统介绍了有关全球气候变化对中国农业生产影响研究的现状与进展,包括气候变化对农业影响的研究方法、大气中温室气体浓度增加对农作物的影响试验、气候变化对农业气候资源的影响、气候变化对农作物生长发育和产量的影响、气候变化对农业种植制度和品种布局的影响、气候变化对农作物气候生产潜力和气候资源利用率的影响等,指出当前在研究气候变化对农业影响评估中存在的问题,提出了今后应加强对气候变化情景和预测模式不确定性的研究、气候变化对农业影响的方法研究。此外,气候变化背景下极端天气气候事件对农业生产的影响以及气候变化对农业病虫害的影响研究等仍较薄弱,有待进一步加强和深入。  相似文献   

15.
A four step methodology has been developed for study of the regional impacts of climate change and the possible responses thereto. First the region's climate sensitive sectors and total economy are described (Task A, current baseline). Next a scenario of climate change is imposed on the current baseline (Task B, current baseline with climate change). A new baseline describing the climate sensitive sectors and total regional economy is projected for some time in the future (Task C, future baseline, year 2030) in the absence of climate change. Finally, the climate change scenario is reimposed on the future baseline (Task D, future baseline with climate change). Impacts of the climate change scenario on the current and future regional economies are determined by means of simulation models and other appropriate techniques. These techniques are also used to assess the impacts of an elevated CO2 concentration (450 ppm) and of various forms of adjustments and adaptations. The region chosen for the first test of the methodology is composed of the four U.S. states of Missouri, Iowa, Nebraska and Kansas. The climate change scenario is the actual weather of the 1930s decade in the MINK region. ‘Current’ climate is the actual weather of the period 1951–1980.  相似文献   

16.
Three environmental change scenarios (the best scenario, the most likely scenario and the worst scenario) were used by the APSIM (Agricultural Production System sIMulator) Wheat module to study the possible impacts of future environmental change (climate change plus pCO2 change) on wheat production in the Mid-Lower North of South Australia. GIS software was used to manage spatial-climate data and spatial-soil data and to present the results. Study results show that grain yield (kg ha−1) was adversely affected under the worst environmental change scenario (−100% ∼ −42%) and the most likely environmental change scenario (−58% ∼ −3%). Grain nitrogen content (% N) either increased or decreased depending on the environmental change scenarios used and climate divisions (−25% ∼ +42%). Spatial variability was found for projected impact outcomes within climate divisions indicating the necessity of including the spatial distribution of soil properties in impact assessment.  相似文献   

17.
未来气候变化对东北玉米品种布局的影响   总被引:4,自引:1,他引:3       下载免费PDF全文
为探求未来气候变化对我国东北玉米品种布局的影响,基于玉米生产潜力和气候资源利用率,结合区域气候模式输出的2011—2099年RCP_4.5,RCP_8.5两种气候背景气象资料和1961—2010年我国东北地区91个气象站的观测数据,分析了未来气候变化情况下,东北玉米品种布局、生产潜力、气候资源利用率的时空变化。结果表明:未来东北地区玉米可种植边界北移东扩,南部为晚熟品种,新扩展区域以早熟品种为主,不能种植区域减少。未来玉米生产潜力为南高北低,增加速率均高于历史情景,水分适宜度最低,而历史情景下温度是胁迫玉米生产的关键因子。未来东北玉米对气候资源利用率整体下降,其中RCP8.5情景利用率最低。  相似文献   

18.
The impacts of climate change on agriculture may add significantly to the development challenges of ensuring food security and reducing poverty. We show the possible impacts on maize production in Africa and Latin America to 2055, using high-resolution methods to generate characteristic daily weather data for driving a detailed simulation model of the maize crop. Although the results indicate an overall reduction of only 10% in maize production to 2055, equivalent to losses of $2 billion per year, the aggregate results hide enormous variability: areas can be identified where maize yields may change substantially. Climate change urgently needs to be assessed at the level of the household, so that poor and vulnerable people dependent on agriculture can be appropriately targeted in research and development activities whose object is poverty alleviation.  相似文献   

19.
Climate change and climate variability affect households in developing countries both directly through their impact on crop yields and indirectly through their impact on wages, food prices and the livelihoods of the poor. Therefore, vulnerable household groups cannot be identified without considering their position in and access to markets. I illustrate the effects – transmitted through markets – that are significant in household exposure, sensitivity and adaptive capacity to climate change by simulating productivity shocks to maize up to 2030 due to climate change in a computable general equilibrium model of Malawi. The results show that rural households with large land holdings may benefit from the adverse impact of climate change on maize yields as a result of increased maize prices. Urban poor and small-scale farmers are vulnerable to climate change due to the large portion of their incomes spent on food. Existing vulnerability measures that do not consider equilibrium effects and characterise all farmers as vulnerable may therefore be misleading.  相似文献   

20.
Agriculture is both vulnerable to climate change impacts and a significant source of greenhouse gases. Increasing agriculture’s resilience and reducing its contribution to climate change are societal priorities. Survey data collected from Iowa farmers are analyzed to answer the related research questions: (1) do farmers support adaptation and mitigation actions, and (2) do beliefs and concerns about climate change influence those attitudes. Results indicate that farmers who were concerned about the impacts of climate change on agriculture and attributed it to human activities had more positive attitudes toward both adaptive and mitigative management strategies. Farmers who believed that climate change is not a problem because human ingenuity will enable adaptations and who did not believe climate change is occurring or believed it is a natural phenomenon—a substantial percentage of farmers—tended not to support mitigation.  相似文献   

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