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1.
1960—2010年中国西南地区区域性气象干旱事件的特征分析 总被引：4，自引：1，他引：3
利用区域性极端事件客观识别法（Objective Identification Technique for Regional Extreme Events,OITREE）和1960—2010年中国西南地区（四川、云南、贵州省和重庆市）101个站综合气象干旱指数（CI）进行区域性气象干旱事件识别研究,确定了相应的OITREE方法参数组,并识别得出87次中国西南地区区域性气象干旱事件,其中9次达到极端强度,而2009年9月—2010年4月发生的特大干旱是中国西南地区近50年最严重的区域性气象干旱事件。进一步分析表明,中国西南地区区域性气象干旱事件的持续时间一般为10—80 d,最长可达231 d;11—4月是西南地区的旱季。云南和四川南部是西南干旱的频发和强度中心地区;强的（极端及重度）干旱事件可分为5种分布类型,其中南部型出现机会最多。过去50年西南地区区域性气象干旱事件频次显著增多,强度有所增强,其主要原因可能是该地区降水量显著减少所致,而气温升高也起到了推波助澜的作用。 相似文献
2.
基于CI指数的河南省近40a干旱特征分析 总被引：7，自引：0，他引：7
基于河南省113个气象站1970～2007实测气象资料,利用气象干旱综合指数对河南省近40 a的干旱特征进行了统计分析.首先计算了历史逐日的CI指数,统计近40 a各站点出现的干旱过程、各时段的干旱事件,在此基础上统计了河南省历年各地区干旱发生的频率、覆盖范围,分析了干旱发生范围的年际变化和不同强度干旱的空间分布特征.分析结果表明:河南省伏旱发生频率最高为63.6%,冬季干旱发生频率最低为48.8%,春旱和秋旱发生频率相近,分别为55.4%和56.9%;全省大范围干旱发生的年份春季和秋季较多分别有9 a,冬季最少只有5 a;春季豫北各等级干旱发生天数均较高,夏季和秋季全省易发生大范围轻旱,重旱发生较少,冬季轻旱和中旱呈显著的纬向分布,南少北多,和降水的分布有较好的负相关性. 相似文献
3.
1959-2003年青海省干湿变化分析 总被引：1，自引：0，他引：1
利用青海省1959-2003年气象资料,计算了修正的Palmer干旱指数,并对其进行了分析。结果表明：在青海省旱涝监测中,PDSI指数反映旱涝程度更为客观;青海省的干旱主要以轻旱为主;夏秋季年际干湿交替较冬春季频繁,变化振幅也较大;秋季青海省干旱化倾向最为严重,冬春季出现轻旱几率最大。另外,春季干旱总面积在减小;夏季轻旱面积增加,而中旱、重旱面积在减小;秋冬季重旱面积在增加。 相似文献
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5.
《干旱气象》2015,(4)
针对目前各种干旱指数对干旱事件整体识别能力的局限性,采用一种新的客观识别方法"区域性极端事件客观识别方法(OITREE)"对2009~2010年中国西南地区的秋冬春连旱进行了特征识别。结果表明:(1)此次干旱事件的发生时段为2009年8月25日至2010年4月18日,历时237 d,为近50 a(1961~2010年)综合强度排名第五位的干旱事件,是一次极端干旱事件;(2)此次极端干旱过程最大影响面积为576.82万km2,影响范围涉及到云南全省、四川南部、贵州大部(主要是西部)以及重庆、广西西部,其中,云南、贵州和广西3省交界区干旱最严重,其次为云南的中部和中西部,且云南省不论受旱面积还是受旱强度都是最大的;(3)此次干旱过程有4个明显变化阶段:干旱增强、减弱、再增强、最后解除。第一阶段为2009年8月25日至10月下旬,干旱开始发展并持续增强,影响范围最大可达约370万km2,包括西南、华南、华东、华北及东北南部的小部分地区,持续达2个月,受影响的核心区域除了西南地区以外,还有华北和华南的部分区域;第二阶段为2009年11月初至12月中旬,干旱强度急剧下降,影响范围最小只有约50万km2,主要在西南地区,持续时间只有1个月;第三阶段,2009年12月中旬至2010年3月下旬,旱情再一次增强,干旱面积再次扩大,影响范围最大可达约200万km2,包括西南及西北地区东部,持续时间为3个月,是4个阶段中发展时间最长的,主要受影响的核心区域为西南地区;第四阶段,2010年3月下旬至4月中旬,干旱逐渐缓解,直到过程结束,旱情解除。OITREE方法能从不同层次和方面完整地描述干旱事件的时空变化特点,其判别结果与实际情况基本一致,是一种有效监测干旱的新方法。 相似文献
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近54年柳州干旱的时空特征分析 总被引：1，自引：0，他引：1
《气象研究与应用》2015,(3)
基于1961-2014年逐日降水资料,用降水量距平百分率作为划分干旱的指标,对柳州各季节干旱的时空特征进行了分析,结果为:(1)春季柳州干旱频数的空间分布特征是北部和东部多、其他地区少,夏季西多东少,秋季东北部最多、其他地区接近,冬季西南部多、东北部少、其他地区居中。柳州北部的干旱事件以轻旱、中旱为主,重旱、特旱事件主要发生在在中部和南部地区。(2)从春季到冬季,柳州的干旱发生严重程度有随时间递增的趋势,全市性的中旱、重旱、特旱事件主要发生在秋季和冬季,春季、夏季干旱事件全部为轻旱。(3)近54年柳州全市性干旱总频数的年代际变化呈单峰型,1980年代为波峰,1960年代和2010年代波谷。各季节干旱频数的年代际变化趋势是:春季和秋季1980年代以前干旱发生较多,1990年代以后干旱发生较少,夏季和冬季1980年代以前干旱发生较少,1990年代以后干旱发生较多。 相似文献
7.
利用1951-2014年全省46个气象站观测资料,建立了吉林省夏旱和春旱对玉米产量影响评估模型.结果表明:吉林省西部地区的夏季干旱与产量之间呈线性关系,气象产量随夏季干旱程度的增加而减少;其他地区夏旱与产量大多呈二次或三次曲线关系,当干旱指数接近或达到中等干旱时,气象产量达到峰值点;春旱不是影响气象产量的主要因素;对于中西部地区,当出现轻旱时,发生在作物需水临界期的干旱年份的减产频率并不高于发生在其他时期;对全省来说,当发生中等程度以上的夏旱时,往往也出现作物需水临界期干旱;发生中等程度夏旱的减产频率,并不比发生轻度夏旱的减产频率高;当发生严重夏旱时,减产频率明显增加. 相似文献
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2011年中国气候概况 总被引：9，自引：3，他引：6
2011年,我国气候总体呈现暖干特征。全国年平均气温较常年偏高0．5℃,为1997年以来连续第15个暖年;年降水量556．8mm,较常年偏少9％,为1951年以来最少。年内,我国未出现大范围持续性严重干旱和流域性洪涝灾害,低温冰冻和雪灾、局地强对流、热带气旋灾害较轻。但区域性、阶段性气象灾害频发。华北、黄淮出现近41年来最重秋冬连旱;长江中下游出现近60年来最重冬春连旱,6月旱涝急转,发生暴雨洪涝灾害;西南出现近60年来最重夏秋旱;华西和黄淮秋汛明显;华南南部10月发生较重暴雨灾害;强降水造成北京等大城市发生内涝;夏季南方大部持续高温,多地高温破历史纪录;台风纳沙、梅花影响范围广、致灾程度较重。2011年中国气象灾害为正常偏轻年份,直接经济损失偏多,死亡人数和受灾面积均为1990年以来最少。 相似文献
10.
基于前期降水指数的气象干旱指标及其应用 总被引：3，自引：0，他引：3
从气象干旱定义出发,考虑干旱累积效应,借鉴前期降水指数（API）和标准化降水指数（SPI）,建立基于标准化前期降水指数（SAPI）的逐日气象干旱指标,并利用1961-2010年全国632个台站的气象资料分析SAPI的适用性特征。结果表明：逐日SAPI曲线呈典型“锯齿型”特征,在降水持续偏少时段平稳下降,克服了基于“等权累加”建立的综合气象干旱指数由于前期降水移出计算窗口而导致的“不合理旱情加剧”问题,能够精细刻画干旱发生、发展和结束过程。SAPI敏感性分析表明,加剧一个干旱等级需要的无雨日数在降水越少的季节（地区）越多, 减缓一个干旱等级需要的日降水量在降水越少的季节（地区）越少。各等级旱日频率总体上与理论频率一致。降水量较少的季节（地区）,轻旱、中旱及总旱频率略高于降水量较多的季节（地区）,而重旱、特旱频率时空特征相反。1961-2010年全国平均各等级旱日频率均呈下降趋势,其中特旱较为明显,但具有复杂的时空特征：9-11月各等级旱日频率显著增加,其余月份以减少为主;各等级旱日频率总体上呈“西减东增”趋势。 相似文献
11.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics. 相似文献
12.
Yuepeng PAN Mengna GU Yuexin HE Dianming WU Chunyan LIU Linlin SONG Shili TIAN Xuemei Lü Yang SUN Tao SONG Wendell W. WALTERS Xuejun LIU Nicholas A. MARTIN Qianqian ZHANG Yunting FANG Valerio FERRACCI Yuesi WANG 《大气科学进展》2020,37(9):933-938
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on 相似文献
13.
《大气和海洋科学快报》2013,(4):227
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. 相似文献
14.
Connections between the Eurasian teleconnection and concurrent variation of upper-level jets over East Asia 总被引：3，自引：0，他引：3
The variation of the East Asian jet stream(EAJS) associated with the Eurasian(EU) teleconnection pattern is investigated using 60-yr NCEP–NCAR daily reanalysis data over the period 1951–2010. The EAJS consists of three components: the polar front jet(PFJ); the plateau subtropical jet(PSJ); and the ocean subtropical jet(OSJ). Of these three jets over East Asia,the EU pattern exhibits a significant influence on the PFJ and OSJ. There is a simultaneous negative correlation between the EU pattern and the PFJ. A significant positive correlation is found between the EU pattern and the OSJ when the EU pattern leads the OSJ by about 5 days. There is no obvious correlation between the EU pattern and the PSJ. The positive EU phase is accompanied by a weakened and poleward-shifted PFJ, which coincides with an intensified OSJ. A possible mechanism for the variation of the EAJS during different EU phases is explored via analyzing the effects of 10-day high-and low-frequency eddy forcing. The zonal wind tendency due to high-frequency eddy forcing contributes to the simultaneous negative correlation between the EU pattern and the PFJ, as well as the northward/southward shift of the PFJ. High- and low-frequency eddy forcing are both responsible for the positive correlation between the EU pattern and the OSJ, but only high-frequency eddy forcing contributes to the lagged variation of the OSJ relative to the EU pattern. The negative correlation between the EU pattern and winter temperature and precipitation anomalies in China is maintained only when the PFJ and OSJ are out of phase with each other. Thus, the EAJS plays an important role in transmitting the EU signal to winter temperature and precipitation anomalies in China. 相似文献
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<p>PARTITION OF SEASON BASED ON MULTIELEMENTS AND THE DECADAL CHANGE OF SEASON DURATION IN CHINA</p>
<p>Using the multielements similarity measurement method and 1950–C2017 NCEP/NCAR gridded daily reanalysis datasets, we analyzed season duration in China during 1950–C2016, and we defined the element with maximum absolute sensitivity as the key impact element at each point using the sensitivity analysis method. The decadal change of season duration and its key impact element before and after 1980 were studied. The results indicated obvious meridional and zonal differences in the distribution of season duration for the 67-year average, and that the key impact element has the same distribution characteristics as season duration. In addition, complementary relationships were found between the durations of spring and summer, autumn and winter, and the cold and warm seasons. Of those, the complementary relationship between the durations of spring and summer was strongest and the regions of complementarity were numerous. The complementary regions of autumn and winter durations were found mainly in western China. In the cold and warm seasons, the complementary regions were widespread and the complementary relationship was generally weak. Comparison of the periods before and after 1980 revealed an east–Cwest difference in the interdecadal variation of season duration. Interdecadal variation in spring and summer was found concentrated in northern and western regions, while that in autumn and winter was concentrated in the western region. Areas of significant interdecadal variation of the key elements were found concentrated in northern and western regions, corresponding well with the areas of significant interdecadal variation of season duration.</p> 相似文献
16.
By using the gauged rainfall in 160 stations within mainland China and the NCEP/NCAR reanalysis data, the impacts of anomalous SST in Kuroshio and its extension on precipitation in Northeast China were investigated. The results show that a difference in the meridional circulation such as the East Asia/Pacific teleconnection pattern(EAP)may be responsible for the difference in rainfall between 1998 and 2010. In comparison with 1998, the anomalous meridional circulation pattern in 2010 shifted northeastward, and then the western subtropical high, the mid-latitudinal trough and the northeastern Asia blocking high also shifted northeastward, causing intensified convergence of the cold and warm air masses at the southern region and thus more rainfall in the southwestern region and less in the northwestern region. In 1998, the anomalous cyclone, one component of the meridional pattern, located at the Songhuajiang-Nengjiang River basin, resulted in more rainfall in the majority of the area. The results of observation and the model show that the difference in SSTA in Kuroshio and its extension under the background of different El Ni觡o events is the key point:(1) The anomalous warmth moved westward from the mid-Pacific to the east of the Philippine Sea during the central event, which led the heat resources shifting to the northeast in 2010; subsequently, a shift occurred to the north of the anomalous ascent and decent, followed by a warm SSTA in the region of Kuroshio's extension in 2010 and Kuroshio in 1998.(2) The warm SSTA in the Kuroshio extension causing the Rossby wave activity flux strengthened in 2010, and then the westerly jet shifted northward and extended eastward. A warm SSTA in Kuroshio and cold SSTA in its extension in 1998 caused the westerly jet to shift southward and weaken. As a result,the anomalous anticyclone and cyclone shifted northward in 2010, and the blocking high also shifted northward. 相似文献
17.
Understanding potential future influence of environmental, economic, and social drivers on land-use and sustainability is critical for guiding strategic decisions that can help nations adapt to change, anticipate opportunities, and cope with surprises. Using the Land-Use Trade-Offs (LUTO) model, we undertook a comprehensive, detailed, integrated, and quantitative scenario analysis of land-use and sustainability for Australia’s agricultural land from 2013–2050, under interacting global change and domestic policies, and considering key uncertainties. We assessed land use competition between multiple land-uses and assessed the sustainability of economic returns and ecosystem services at high spatial (1.1 km grid cells) and temporal (annual) resolution. We found substantial potential for land-use transition from agriculture to carbon plantings, environmental plantings, and biofuels cropping under certain scenarios, with impacts on the sustainability of economic returns and ecosystem services including food/fibre production, emissions abatement, water resource use, biodiversity services, and energy production. However, the type, magnitude, timing, and location of land-use responses and their impacts were highly dependent on scenario parameter assumptions including global outlook and emissions abatement effort, domestic land-use policy settings, land-use change adoption behaviour, productivity growth, and capacity constraints. With strong global abatement incentives complemented by biodiversity-focussed domestic land-use policy, land-use responses can substantially increase and diversify economic returns to land and produce a much wider range of ecosystem services such as emissions abatement, biodiversity, and energy, without major impacts on agricultural production. However, better governance is needed for managing potentially significant water resource impacts. The results have wide-ranging implications for land-use and sustainability policy and governance at global and domestic scales and can inform strategic thinking and decision-making about land-use and sustainability in Australia. A comprehensive and freely available 26 GB data pack (http://doi.org/10.4225/08/5604A2E8A00CC) provides a unique resource for further research. As similarly nuanced transformational change is also possible elsewhere, our template for comprehensive, integrated, quantitative, and high resolution scenario analysis can support other nations in strategic thinking and decision-making to prepare for an uncertain future. 相似文献
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Characterization and source apportionment of volatile organic compounds in urban and suburban Tianjin,China 总被引：1，自引：0，他引：1
Tianjin is the third largest megacity and the fastest growth area in China, and consequently faces the problems of surface ozone and haze episodes. This study measures and characterizes volatile organic compounds(VOCs), which are ozone precursors, to identify their possible sources and evaluate their contribution to ozone formation in urban and suburban Tianjin,China during the Ha Chi(Haze in China) summer campaign in 2009. A total of 107 species of ambient VOCs were detected,and the average concentrations of VOCs at urban and suburban sites were 92 and 174 ppbv, respectively. Of those, 51 species of VOCs were extracted to analyze the possible VOC sources using positive matrix factorization. The identified sources of VOCs were significantly related to vehicular activities, which specifically contributed 60% to urban and 42% to suburban VOCs loadings in Tianjin. Industrial emission was the second most prominent source of ambient VOCs in both urban and suburban areas, although the contribution of industry in the suburban area(36%) was much higher than that at the urban area(16%). We conclude that controlling vehicle emissions should be a top priority for VOC reduction, and that fast industrialization and urbanization causes air pollution to be more complex due to the combined emission of VOCs from industry and daily life, especially in suburban areas. 相似文献
20.
碳交易政策的经济影响:以广东省为例 总被引：1，自引：0，他引：1
通过构建广东省两区域动态模型,对广东省碳交易及其他政策措施进行定量评估,分析实施可调控总量的碳交易政策机制对广东省及参与交易部门的经济影响。研究结果表明,按照减排情景到2015年广东完成19.5%的碳强度下降目标,相比基准情景,GDP将减少0.7%;按照强减排情景到2015年将完成20.5%的碳强度下降目标,相比基准情景GDP将减少0.9%;如果在强减排情景的基础上实施碳交易政策,GDP相对基准情景减少0.8%,到2015年实施碳交易政策可减少GDP损失约90亿元,说明广东建立碳排放权交易机制能够发挥支持经济发展和节能减碳双赢的作用。 相似文献