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1.
This paper examines the combined impacts of food price and income shocks on household food security and economic well-being in low-income rural communities. Using longitudinal survey data of 1800 rural households from 12 districts of Bangladesh over the period 2007–2009, we estimated a three-stage hierarchical logit model to identify the key sources of household food insecurity. The first-difference estimator was then employed to compare pre- and post-shock expenditure for those households that experienced acute food shortages and those that managed to avoid the worst impacts of the shocks. On the basis of our results we conclude that: (1) the soaring food prices of 2007–2009 unequivocally aggravated food insecurity in the rural areas of Bangladesh; (2) the subsequent income shocks of 2007–2009 contributed toward worsening food insecurity; (3) the adverse impacts of these shocks appeared to have faded over time due to labor and commodity market adjustments, regional economic growth, and domestic policy responses, leaving no profound impacts on households’ economic well-being in most cases; and (4) although the immediate adverse consequences of rising food prices were borne disproportionately by the poor, the longer term consequences were distributed more evenly across the rich and poor and were favorable for the day laborers.  相似文献   

2.
近年来中国东北地区污染事件频发,为揭示该地区重污染天气分布特征,利用2014—2017年中国东北地区40个城市空气质量数据及对应的高低空天气形势资料,统计分析得到中国东北地区大气污染状况的变化特征以及区域重污染事件的天气学特征。结果表明:2015—2017年中国东北地区PM2.5和PM10年平均质量浓度呈下降趋势,其中PM2.5年平均质量浓度下降的更快,PM2.5最大值出现在辽宁和吉林中部地区约为90—100 μg·m-3,SO2年平均质量浓度较高值分布在辽宁西部地区约为50 μg·m-3,而NO2最大值出现在沈阳—长春—哈尔滨一带,约为45 μg·m-3,CO质量浓度最大值分布在东北沿海地区约为1.6 mg·m-3,相反中国东北地区O3年平均质量浓度呈上升趋势,最大值出现在沿海的大连及营口等地,约为100 μg·m-3。污染物浓度变化具有鲜明的季节变化特征,不同地区PM2.5和PM10与AQI最大值均出现在冬季,SO2冬季质量浓度最大值出现在沈阳(180 μg·m-3),NO2与CO冬季最大值出现在哈尔滨(80 μg·m-3,1.8 mg·m-3)。相反,O3最大值出现在夏季沈阳地区约为140—150 μg·m-3。重度污染级别(200 μg·m-3≤PM2.5 < 300 μg·m-3)和严重污染级别(PM2.5>300 μg·m-3)的空气质量表现出以哈尔滨为中心,向周围迅速减少,辽宁中部又略有增加的特征;中度污染(150 μg·m-3≤PM2.5 < 200 μg·m-3)的天数沈阳>哈尔滨>长春,轻度污染(100 μg·m-3≤PM2.5 < 150 μg·m-3)的天数是沈阳>长春>哈尔滨。引发中国东北地区重污染的天气形势大致可分为高压型,低压型和北高南低型3种,出现比例分别为62%、27%和11%;高压型850 hPa高压脊东移经过中国东北地区,地面处于高压南部或弱高压中心,有时在黑龙江北部或辽宁西南部连续有弱小的低压生成并快速东移过境;低压型850 hPa低压系统发展并东移经过中国东北地区,地面处于低压后弱高压中;北高南低型850 hPa和地面中国东北地区受北面高压和南面低压的共同影响。  相似文献   

3.
基于1961-2018年1 057个地面气象站均一化气温日值数据和通过均一化检验的日降水量资料,统计得到冬春季低温连阴雨过程,分析其时空分布及变化特征。结果表明,湖南、贵州、江西三省为低温连阴雨集中发生地区,连续最长低温连阴雨超过15 d的台站集中在25°~31°N之间的区域。由经验正交函数方法分析表明,南方地区低温连阴雨日数总体上表现为一致偏多或偏少的分布型,且具有东北部与西南部反相变化、东部与西部反相变化的分布型。南方冬春季平均低温连阴雨日数总体呈减少趋势,约为-0.17 d/(10 a)。1960s末期至1990s低温连阴雨日数以偏多为主,从2000年开始以偏少为主。  相似文献   

4.
As adaptation has come to the forefront in climate change discourse, research, and policy, it is crucial to consider the effects of how we interpret the concept. This paper draws attention to the need for interpretations that foster policies and institutions with the breadth and flexibility to recognize and support a wide range of locally relevant adaptation strategies. Social scientists have argued that, in practice, the standard definition of adaptation tends to prioritize economic over other values and technical over social responses, draw attention away from underlying causes of vulnerability and from the broader context in which adaptive responses take place, and exclude discussions of inequality, justice, and transformation. In this paper, we discuss an alternate understanding of adaptation, which we label “living with climate change,” that emerged from an ethnographic study of how rural residents of the U.S. Southwest understand, respond to, and plan for weather and climate in their daily lives, and we consider how it might inform efforts to develop a more comprehensive definition. The discussion brings into focus several underlying features of this lay conception of adaptation, which are crucial for understanding how adaptation actually unfolds on the ground: an ontology based on nature–society mutuality; an epistemology based on situated knowledge; practice based on performatively adjusting human activities to a dynamic biophysical and social environment; and a placed-based system of values. We suggest that these features help point the way toward a more comprehensive understanding of climate change adaptation, and one more fully informed by the understanding that we are living in the Anthropocene.  相似文献   

5.
2016年5月15日清晨河西走廊东部发生区域性强霜冻天气,对农林业生产造成了2004年以来最为严重的灾害。本文利用实时MICAPS常规观测资料、物理量场和河西走廊东部区域内6个国家自动气象观测站和93个区域气象站观测资料,对这次冻害天气过程的天气学成因进行分析,在此基础上分析了霜冻对农业的影响。结果表明强冷空气爆发是造成冻害的直接原因;0 cm地面温度和气温≤0 ℃持续时间长,导致农林作物深度冻伤;前期气温偏高使得农林作物发育期提前,加之霜冻出现时间偏迟,农林作物抵抗冻害的能力明显下降,冻害影响加重;冻害发生后,温度急剧上升、湿度迅速减小,作物水分强烈蒸腾,作物细胞失去受损,导致受灾程度加重。  相似文献   

6.
Using recent advances in statistical crop yield modelling and a unique dataset consisting of yield time series for Russian regions over the period from 1955 to 2012, the study investigates the potential impact of climate change (CC) on the productivity of the three most important grains. Holding current grain growing areas fixed, the aggregate productivity of the three grains is predicted to decrease by 6.7% in 2046–2065 and increase by 2.6% in 2081–2100 compared to 1971–2000 under the most optimistic representative emission concentration pathway (RCP). Based on the projections for the three other RCPs, the aggregate productivity of the three studied crops is assessed to decrease by 18.0, 7.9 and 26.0% in the medium term and by 31.2, 25.9 and 55.4% by the end of the century. Our results indicate that CC might have a positive effect on winter wheat, spring wheat and spring barley productivity in a number of regions in the Northern and Siberian parts of Russia. However, due to the highly damaging CC impact on grain production in the most productive regions located in the South of the country, the overall impact tends to be negative. Therefore, a shift of agricultural production to the Northern regions of the country could reduce the negative impact of CC on grain production only to a limited extent. More vigorous adaptation measures are required to maintain current grain production volumes in Russia under CC.  相似文献   

7.
东北地区玉米不同生长阶段干旱冷害危险性评价   总被引:6,自引:2,他引:6  
利用东北地区35个农业气象站1961—2010年气象资料、玉米产量资料和1981—2010年玉米生育期资料,选用合适的干旱指标和冷害指标,结合自然灾害风险理论建立了灾害危险性评价模型。基于灾害判别结果和历史灾情资料,从典型灾害年中提取不同灾种的影响差异,构成权重系数,对东北地区玉米不同生长阶段和整个生育期干旱、冷害危险性进行评价。结果表明,东北地区干旱、冷害危险性在玉米生长前期(出苗—拔节阶段)主要集中在东北地区东南部,此阶段主要以冷害为主;而在玉米生长后期(抽雄—成熟阶段),风险高值区转移到西部,此阶段以干旱为主。生长前期和生长后期对整个生长阶段危险性的贡献值分别为0.3473和0.6527。东北地区的主要气象灾害正逐渐从冷害向干旱转变,冷害发生的频次逐渐减少,而干旱发生的频次快速增多,影响的范围也迅速增大。  相似文献   

8.
Northeast China is the main crop production region in China, and future climate change will directly impact crop potential yields, so exploring crop potential yields under future climate scenarios in Northeast China is extremely critical for ensuring future food security. Here, this study projected the climate changes using 12 general circulation models (GCMs) under two moderate Representative Concentration Pathway (RCP) scenarios (RCP 4.5 and 6.0) from 2015 to 2050. Then, based on the Global Agro-ecological Zones (GAEZ) model, we explored the effect of climate change on the potential yields of maize and paddy rice in Northeast China during 2015–2050. The annual relative humidity increased almost throughout the Northeast China under two RCPs. The annual precipitation increased more than 400 mm in some west, east, and south areas under RCP 4.5, but decreased slightly in some areas under RCP 6.0. The annual wind speed increased over 2 m/s in the west region. The annual net solar radiation changes varied significantly with latitude, but the changes of annual maximum temperature and minimum temperature were closely related to the terrain. Under RCP 4.5, the average maize potential yield increased by 34.31% under the influence of climate changes from 2015 to 2050. The average rice potential yield increased by 16.82% from 2015 to 2050. Under RCP 6.0, the average maize and rice potential yields increased by 25.65% and 6.34% respectively. The changes of maize potential yields were positively correlated with the changes of precipitation, wind speed, and net solar radiation (the correlation coefficients were > 0.2), and negatively correlated with the changes of relative humidity, minimum and maximum temperature under two RCPs. The changes of rice potential yields were positively correlated with the changes of precipitation (correlation coefficient = 0.15) under RCP 4.5. Under RCP 6.0, it had a slight positive correlation with net solar radiation, relative humidity, and wind speed.  相似文献   

9.
北极涛动年代际变化对华北地区干旱化的影响   总被引:16,自引:10,他引:16  
华北地区夏季降水在20世纪70年代中期以后进入年代际偏少阶段,表现出明显的干旱化趋势。华北干旱加剧具有特殊的大气环流背景,主要表现为在20世纪70年代中期以后亚洲大陆东部的热低压减弱,同时对流层低层到高层东亚夏季风环流减弱。这种异常的大气环流背景主要是由海陆热力差异和北极涛动的年代际变化造成的。近二十几年来,北极涛动维持在高指数位相是导致东亚地区大气环流异常的重要原因,并由此造成了华北干旱的加剧。  相似文献   

10.
针对2018年4月3-5日东北冷空气回流到京津冀地区造成复杂相态降水过程典型华北回流天气个例,利用ERA5再分析资料和MICAPS地面资料,详细分析了冷空气路径、形态、对降水范围及相态的影响等。分析表明:回流冷空气对京津冀地区的影响,可分为4个阶段,即低层冷舌侵入、沿山堆积扩散、增强维持、变性消散阶段。在低层冷舌侵入阶段,冷空气以冷舌形式经东北、渤海侵入京津冀地区,冷舌在不同高度位置不同;冷舌在垂直方向位于干、湿过渡区,降水粒子经冷舌下方干区蒸发,造成阴天无降水天气。在沿山堆积扩散阶段,低层冷空气遇太行山堆积并向南北以扇形形式扩散,较高层次冷空气西边界扩散至太行山山区;燕山南部、太行山东部存在深厚湿层,且温度较低,出现降雪;距离山脉较近的平原地区出现雨夹雪或雪;距离山脉较远的平原地区无降水。在增强维持阶段,冷空气强度达到最强,范围达到最大;深厚湿层从太行山、燕山向平原扩展,降水范围扩大,降水相态主要取决于近地面温度。在冷空气变性消散阶段,较高层次回暖先于较低层次,冷空气变性消失,降水趋于结束。  相似文献   

11.
Interannual and decadal variations of winter snow cover over the Qinghai-Xizang Plateau (QXP) are analyzed by using monthly mean snow depth data set of 60 stations over QXP for the period of 1958 through 1992. It is found that the winter snow cover over QXP bears a pronounced quasi-biennial oscillation, and it underwent an obvious decadal transition from a poor snow cover period to a rich snow cover period in the late 1970’s during the last 40 years.It is shown that the summer rainfall in the eastern China is closely associated with the winter snow cover over QXP not only in the interannual variation but also in the decadal variation. A clear relationship exists in the quasi-biennial oscillation between the summer rainfall in the northern part of North China and the southern China and the winter snow cover over QXP. Furthermore, the summer rainfall in the four climate divisions of Qinling-Daba Mountains, the Yangtze-Huaihe River Plain, the upper and lower reaches of the Yangtze River showed a remarkable transition from drought period to rainy period in the end of 1970’s, in good correspondence with the decadal transition of the winter snow cover over QXP.  相似文献   

12.
Tourism in island states is vulnerable to climate change because it may result in detrimental changes in relation to extreme events, sea level rise, transport and communication interruption. This study analyses adaptation to climate change by tourist resorts in Fiji, as well as their potential to reduce climate change through reductions in carbon dioxide emissions. Interviews, site visitations, and an accommodation survey were undertaken. Many operators already prepare for climate-related events and therefore adapt to potential impacts resulting from climate change. Reducing emissions is not important to operators; however, decreasing energy costs for economic reasons is practised. Recommendations for further initiatives are made and synergies between the adaptation and mitigation approaches are explored.  相似文献   

13.
1.IntroductionInrecentyearsmanystudiesshowthatozoneinthesurfacelayerisanimportantfactorforcontrolingatmosphericchemistryreact...  相似文献   

14.
以东北玉米冷害预测为例,介绍了近年发展的基于热量指数预测的热量年型统计预测模型和基于玉米生长模式的机理性预测模型,比较了两类模型在预报原理、预报对象、预报时效及准确率等方面的各自差别和利弊,探讨了两类模型取长补短优势互补的可能方法,展望了农业气象灾害预测预警技术发展的若干问题。  相似文献   

15.
近年来,随着大气观测技术的快速发展,为冬季大雪年际变化研究提供了一些新的观测事实,增加了新的认识。认为大气环流对降雪的年际变化的影响只是重要方面之一。新的观测事实启示研究者,冬雪的年际变化和差异还可能与其他影响气候变化有更为复杂的因素——大气气溶胶特征有关。基于1980-2008年中国气象台站降水量资料和1980-2005年北方地区大气气溶胶光学厚度(AOD)资料,研究中国北方地区大范围多雨雪以及少雨雪年度变化与大气气溶胶分布特征的关系。结果表明:1980-2008年,中国北方地区典型的多雨雪年为1980、1984、1989、1993、1998、2003年和2006年;少雨雪年为1982-1983、1985-1988、1997、2001年和2005年。根据1980-2005年华北逐年冬半年雨雪总量与北方地区同期AOD相关分析,揭示中国北方地区雨雪年度变化与气溶胶光学厚度(AOD_550m)的年度变化存在正相关,相关系数达到0.001的显著性水平。同期资料AOD。。。分析表明,中国北方地区冬季多雨雪与少雨年大气气溶胶光学厚度差异显著,多雨雪年大气气溶胶光学厚度显著偏厚,中国华北北部、东北南部地区AOD正距平的平均值达到1×10。-5×10^-3,冬季北方地区少雨雪年与此差异显著,AOD为显著负距平,其平均值为-5×10^-3。  相似文献   

16.
稻茬冬小麦不同播种方式和播种量试验于2008—2009年度在江苏省农业科技综合展示基地(宿迁点)进行,试验共设计4种播种方式和3个播种量水平,研究分析不同播种方式和播种量及气象条件对稻茬冬小麦生长发育、抗逆性和产量的影响。结果表明:播种方式和播种量对冬小麦的生长发育及产量有显著影响,在生产实际中应结合具体情况采取适当的播种方式,播种量水平以每亩20万株左右基本苗较理想。在粳稻收获较晚,冬小麦无法适期播种时,可以采取稻田套播方式,播种量要适当增加;籼稻腾茬早的,可以选择收获后7 d左右人工撒播或条播;在茬口和气候等条件适宜的情况下,尽可能采取水稻收获后2 d左右进行冬小麦播种。条播能更充分的利用光温水等气候资源。  相似文献   

17.
我国西南地区干旱变化及对贵州水稻产量影响   总被引:1,自引:1,他引:1       下载免费PDF全文
近几年,我国西南地区干旱频繁发生,严重影响农业生产。为了探讨干旱和水稻产量之间关系的复杂性,采用中国气象局国家气象信息中心提供的西南地区348个站气象数据,计算了西南地区干旱的变化趋势,并利用2000—2011年贵州省县级水稻产量资料分析了干旱对水稻单产的影响,探讨了干旱、水资源灌溉以及水稻产量之间的关系。结果表明:1951—2012年西南地区降水量平均减少16.9 mm/10 a,特别是8—10月降水量明显减少。同时,西南地区干旱日数呈上升趋势,平均增加3.3 d/10 a。对比水稻产量发现,当累计干旱日数少于40 d时,干旱对水稻产量一般不会造成影响;当累计干旱日数超过86 d时,干旱造成水稻减产20%~73%,这意味着当累计干旱日数超过3个月时,江河塘库蓄水将受到影响,进而影响水稻的灌溉,造成水稻严重减产;当累计干旱日数为40~86 d时,水稻减产一般少于20%,但地区差异较大。  相似文献   

18.
稻茬冬小麦不同播种方式和播种量试验研究   总被引:1,自引:0,他引:1  
稻茬冬小麦不同播种方式和播种量试验于2008—2009年度在江苏省农业科技综合展示基地(宿迁点)进行,试验共设计4种播种方式和3个播种量水平,研究分析不同播种方式和播种量及气象条件对稻茬冬小麦生长发育、抗逆性和产量的影响。结果表明:播种方式和播种量对冬小麦的生长发育及产量有显著影响,在生产实际中应结合具体情况采取适当的播种方式,播种量水平以每亩20万株左右基本苗较理想。在粳稻收获较晚,冬小麦无法适期播种时,可以采取稻田套播方式,播种量要适当增加;籼稻腾茬早的,可以选择收获后7 d左右人工撒播或条播;在茬口和气候等条件适宜的情况下,尽可能采取水稻收获后2 d左右进行冬小麦播种。条播能更充分的利用光温水等气候资源。  相似文献   

19.
Gender-disaggregated, household survey data for Uganda are used to examine how gendered roles and responsibilities influence adoption of drought-tolerant (DT) maize, a new technology that can help smallholder farmers in sub-Saharan Africa adapt to drought risk. Multinomial logit (MNL) regression results indicate that, compared to men farmers, women farmers have much lower adoption of DT maize, mainly due to differences in resource access, notably land, agricultural information, and credit. Differentiation of women and men farmers by various characteristics reveals that whether a male farmer was younger or older, or poor or non-poor has no significant influence on DT maize adoption; but important differences among different categories of women farmers are identified. For example, the farmer group found least likely to adopt DT maize is young, poor women household heads. MNL results also show that wives strongly influence adoption of DT maize on plots controlled by their husbands. We discuss the implications of study findings for the development of well-targeted and socially-inclusive adaptation policies.  相似文献   

20.
春季中国东海黑潮区大气热源异常对中国东部降水的影响   总被引:3,自引:0,他引:3  
采用ERA-interim逐日再分析数据集与中国东部389个站逐日降水资料,通过相关和合成分析讨论了不同时间尺度上,春季中国东海黑潮区上空大气热源异常对东亚大气环流和中国东部降水的影响。观测分析表明,春季中国东海黑潮区上空为一显著的大气热源,大气对该热源的响应在不同时间尺度上表现出不同的形式。在较长时间的季节和年际尺度上,春季中国东海黑潮区大气热源增强时,可在大气对流层低层强迫出偏南气流,同期春季及后期夏季西太平洋副热带高压增强并西伸,相比于热源低值年西北太平洋副热带地区为一反气旋式异常环流所控制,中国长江中下游以南地区降水增多;反之亦然。与年际和季节时间尺度不同,在较短的天气时间尺度上,中国东海黑潮区上空大气热源增强可在其下方强迫出气旋式异常环流。大气热源的增强与中国东部对流层低层气旋式异常环流的东移有关,相应地在中国东部地区出现了显著的降水增多。  相似文献   

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