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河西走廊东部不同气候态气温变化及其对气候评价的影响
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作者 杨晓玲 周华 +2 位作者 陈静 赵慧华 吴雯 《干旱区研究》 CSCD 北大核心 2024年第7期1089-1098,共10页
河西走廊东部是气候变化的敏感区,其气候态的更替对气候评价影响较大。采用河西走廊东部5个国家气象站的1961─2022年逐月气温数据,对比分析河西走廊东部1961─1990年、1971─2000年、1981─2010年和1991─2020年4个气候态气温的差异及... 河西走廊东部是气候变化的敏感区,其气候态的更替对气候评价影响较大。采用河西走廊东部5个国家气象站的1961─2022年逐月气温数据,对比分析河西走廊东部1961─1990年、1971─2000年、1981─2010年和1991─2020年4个气候态气温的差异及其对气候业务评价的影响。结果表明:全区域及各地4个气候态年平均气温均呈升高趋势,P2(1971—2000年气候态)~P4(1991—2020年气候态)气温升高趋势均极显著。从4个气候态气温的差值来看,全区域及各地年、季、月气温基本一致升温,除P3(1981—2010年气候态)和P4外,其他气候态表现为冬季升幅最大,夏季升幅最小,各月升温差异较大,同一季度、同一月份气温升幅存在明显空间差异。气候态平均值更替后,河西走廊东部气温距平明显偏大的特征弱化了,其等级由正距平向负距平方向调整,P1(1961—1990年气候态)~P4年平均气温评价等级高达56%~87%向偏低一级转变,冷冬年份增多17~28 a,暖冬年份减少15~23 a。本研究将为了解河西走廊东部气温的变化规律以及气候业务、决策服务和气象科学研究提供参考依据。 展开更多
关键词 气候变暖 温度气候 变化 气候评价 河西走廊东部
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极端温度气候下园林花卉苗木业抗灾现状及对策 被引量:5
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作者 姚和金 陈志军 周伟军 《广东园林》 2009年第6期46-48,共3页
针对目前极端温度气候频繁发生及对社会经济造成的损失,文章分析了在极端温度气候下我国园林花卉苗木业抗灾减灾存在的问题。同时提出增强园林花卉苗木业抗灾减灾能力,必须建立灾害预警制度,加强灾害评估体系建设,加大科研经费投入,加... 针对目前极端温度气候频繁发生及对社会经济造成的损失,文章分析了在极端温度气候下我国园林花卉苗木业抗灾减灾存在的问题。同时提出增强园林花卉苗木业抗灾减灾能力,必须建立灾害预警制度,加强灾害评估体系建设,加大科研经费投入,加强灾前防范和灾后恢复自救等对策;并建议设立专门园林花卉苗木业国家政策性保险基金,以促进园林花卉苗木业健康发展。 展开更多
关键词 极端温度气候 花卉苗木业 抗灾减灾
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不同季节和气候条件对种公牛精液品质的影响的研究 被引量:9
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作者 徐峥嵘 贺奋义 《中国牛业科学》 2014年第4期26-30,共5页
[目的]研究不同季节气候条件对种公牛精液品质的影响。[方法]从采精种公牛中随机抽出5头,选取气温最高(7月份)最低(1月份)和适中温度(4,9月份)进行试验,分别对不同时期所采得的精液进行检测。[结果]在最高温度月份7月份(25℃)时... [目的]研究不同季节气候条件对种公牛精液品质的影响。[方法]从采精种公牛中随机抽出5头,选取气温最高(7月份)最低(1月份)和适中温度(4,9月份)进行试验,分别对不同时期所采得的精液进行检测。[结果]在最高温度月份7月份(25℃)时5头种公牛的平均精液量为5.88mL,原精活率67.2%,精液密度16.64亿/mL,冻后活率33.8%,生产冻精数143.4剂,精子畸形率23%。1月份环境温度平均在-11.2℃时,5头种公牛的精液量平均为5.7mL,原精活率66.8%,精液密度13.3亿/mL,冻后活率37.4%,生产冻精数为275.8剂,精子畸形率17.8%。在4,9月份环境温度12℃时精液量为6.6mL,原精活率73.2%,精液密度16.92亿/mL,冻后活率41.8%,生产冻精数404.4剂,精子畸形率12.6%。精液量之间差异显著(P〈0.05),原精活率之间差异显著(P〈0.05),精子畸形率之间差异显著(P〈0.05)。冻后活率和冻精生产数差异不显著。[结论]环境温度过高或者过低都会影响精液品质,种公牛在适宜的温度下生产的精液品质也会更加优良,种公牛在温度较高的条件下生产精液品质比在低温条件下还要差,种公牛最适宜的生产温度为12℃~16℃。 展开更多
关键词 气候温度 种公牛 精液 生产 品质
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基于潜在蒸散和干燥度指数的河北省农业气候区划 被引量:11
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作者 杨彬云 吴荣军 关福来 《干旱地区农业研究》 CSCD 北大核心 2009年第6期241-246,共6页
基于Penman-Monteith模型的潜在蒸散和降水量之比计算得到的干燥度指数作为衡量区域干湿状况的重要指标,已成为全球变化研究中的重要气候指标之一。本文利用温度气候带和以干燥度指数划分的干湿气候区作为二级气候区划指标,开展区域尺... 基于Penman-Monteith模型的潜在蒸散和降水量之比计算得到的干燥度指数作为衡量区域干湿状况的重要指标,已成为全球变化研究中的重要气候指标之一。本文利用温度气候带和以干燥度指数划分的干湿气候区作为二级气候区划指标,开展区域尺度的河北省农业气候分区,将河北省农业气候区划分为暖温带半湿润区,冀北中山中温带半湿润偏旱区、太行山暖温带半湿润偏旱区和滨海平原暖温带半湿润偏旱区,冀北高原中温带半干旱区、太行山北段中温带半干旱区和冀中、南平原暖温带半干旱区,中温带半干旱偏旱区。该分区为合理配置农业生产、改进耕作制度以及引入和推广新品种提供气候依据,同时也为相关部门采取应对措施减轻旱涝灾害及其不利影响提供参考。 展开更多
关键词 潜在蒸散 干燥度 温度气候 农业气候区划 河北省
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冬季采暖室外空气温度变化对换热站运行调节的影响
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作者 魏萍 邓震 刘丛伦 《区域供热》 2014年第4期67-69,74,共4页
本文依据多年实际换热站运行经验,结合具体室外温度变化情况,详细论述了在冬季采暖过程中室外空气温度变化对换热站运行调节的影响。
关键词 分户计量 调节气候温度 曲线
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室外温度变化对换热站运行的影响及变频控制的节能效果分析 被引量:1
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作者 梁久永 《中国电子商务》 2012年第15期89-90,共2页
本文依据多年供热运行实践经验,详细阐述了冬季采暖室外温度变化对供热参数的影响,以及变频技术综合应用带来显著一节能塾果,通过定性定量的分析论证,对挟热站节能运行调节具有一定的指导作用。
关键词 气候温度 调节 曲线 变频控制 节能
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基于GIS的泉州农业气候生产潜力估算 被引量:1
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作者 叶晓春 叶晓冰 高习 《中国农业文摘(农业工程)》 2017年第1期30-31,共2页
本文选取泉州市近30年7个自动气象站点逐月、逐年气温和降水气温资料,利用Miami模型和Thornth-waite Memorial模型计算泉州市各县市气温、降水和蒸散量气候生产潜力,并借助GIS空间分析技术,得出泉州市近30年气候生产潜力分布特征:由降... 本文选取泉州市近30年7个自动气象站点逐月、逐年气温和降水气温资料,利用Miami模型和Thornth-waite Memorial模型计算泉州市各县市气温、降水和蒸散量气候生产潜力,并借助GIS空间分析技术,得出泉州市近30年气候生产潜力分布特征:由降水量决定的气候生产潜力值最高,蒸散量次之,温度气候生产潜力值最低;温度气候生产潜力分布特征为中部山区最高,北部高海拔山区最低,沿海次之,降水和蒸散量气候生产潜力分布特征与温度的相反。 展开更多
关键词 年平均气温 年平均降水量 温度气候生产潜力 降水气候生产潜力 蒸散量气候生产潜力
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:38
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarded as the northern limit of the subtropical vegetation zone; 2) the northern limit of subtropical vegetation zone in China is along the northern coast of the Yangtze River, from Hangzhou Bay, via Taihu Lake, Xuancheng and Tongling in Anhui Province, through by southern slope of the Dabie Mountains, to Wuhan and its west, coinciding with a warmth index ( WI ) value of 130-140 ℃·month; 3) the tropical region is limited in a very small area in southeastern Hainan Island and southern edge of Taiwan Island; and 4) considering a significant difference in climates between the southern and northern parts of the warm temperate zone, we suggested that the warm temperate zone in China is divided into two vegetation regions, deciduous broadleaf woodland region and deciduous and evergreen broadleaf mixed forest region, the Qinling Mountain_Huaihe River line being as their boundary. We also claimed that the zonal vegetation in North China is deciduous broadleaf woodland. Finally, we emphasized the importance of dynamic vegetation regionalization linked to climate changes. 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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瓷砖胶在西北地区的应用分析
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作者 李仁华 《居业》 2015年第10X期27 29-,29,共2页
瓷砖胶作为一种新型材料,因其施工速度快、环保性好、施工质量容易得到保证而在工程中应用较为广泛,较多的应用于瓷砖、大理石、花岗岩、马赛克、铜质砖等的粘结施工过程中。本文结合某工程中瓷砖粘结出现的质量问题,分析了温度条件、... 瓷砖胶作为一种新型材料,因其施工速度快、环保性好、施工质量容易得到保证而在工程中应用较为广泛,较多的应用于瓷砖、大理石、花岗岩、马赛克、铜质砖等的粘结施工过程中。本文结合某工程中瓷砖粘结出现的质量问题,分析了温度条件、施工工艺、基层质量等几个方面对瓷砖胶粘结度的影响。 展开更多
关键词 瓷砖胶 气候温度 施工工艺
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分析公路裂缝成因及日常养护关键技术 被引量:1
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作者 苏根栓 《甘肃科技纵横》 2020年第3期45-47,共3页
国省干线公路投入使用后,会因为自然因素、材料因素以及施工等因素影响,出现不同程度、不同大小的裂缝,会对公路性能与使用产生直接影响。鉴于此,公路养护单位加大了对裂缝问题相关内容的研究,通过合理处理手段,保证公路性能、质量。本... 国省干线公路投入使用后,会因为自然因素、材料因素以及施工等因素影响,出现不同程度、不同大小的裂缝,会对公路性能与使用产生直接影响。鉴于此,公路养护单位加大了对裂缝问题相关内容的研究,通过合理处理手段,保证公路性能、质量。本论述以某工程实例为例,通过对公路裂缝成因的分析,对日常养护关键技术展开全方面解读,旨在掌握裂缝问题形成原因,做好公路养护与裂缝预防的各项工作。 展开更多
关键词 国省干线 养护关键技术 预防措施 公路裂缝 气候温度
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Soil carbon dioxide fluxes of a typical broad-leaved/Korean pine mixed forest in Changbai Mountain, China 被引量:3
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作者 王琛瑞 吴劼 +1 位作者 梁战备 黄国宏 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期268-272,共5页
The forest ecosystem plays an important role in the global carbon cycling. A study was conducted to evaluate soil CO2 flux and its seasonal and diurnal variation with the air and soil temperatures by using static clos... The forest ecosystem plays an important role in the global carbon cycling. A study was conducted to evaluate soil CO2 flux and its seasonal and diurnal variation with the air and soil temperatures by using static closed chamber technique in a typical broad-leaved/Korean pine mixed forest area on the northern slope of Changbai Mountain, Jilin Province, China. The experiment was carried out through the day and night in the growing season (from June to September) in situ and sample gas was analyzed by a gas chromatograph. Results showed that the forest floor was a large net source of carbon, and soil CO2 fluxes had an obvi-ous law of seasonal and diel variation. The soil CO2 flux of broad-leaved/Korean pine mixed forest was in the range of 0.302.42 mmol穖-2穝-1 with the mean value of 0.98 mmol穖-2穝-1. An examination on the seasonal pattern of soil CO2 emission suggested that the variability in soil CO2 flux could be correlated with variations in soil temperature, and the maximum of mean CO2 flux occurred in July ((1.27±23%) mmol穖-2穝-1) and the minimum was in September ((0.50±28%) mmol穖-2穝-1). The fluctuations in diel soil CO2 flux were also correlated with changes in soil temperature; however, there existed a factor for a time lag. Soil CO2 flux from the forest floor was strongly related to soil temperature and had the highest correlation with temperature at 6-cm depth of soil. Q10 values based on air temperature and soil temperature of different soil depths were at the ranges of 2.09–3.40. 展开更多
关键词 Soil CO2 flux Broad-leaved/Korean pine mixed forest Q10 value Changbai Mountain
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TaiYuan Satellite Launch Center
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作者 Liu Jie 《Aerospace China》 2004年第3期18-19,共2页
There are three major space launch bases in China, the Jiuquan Satellite Launch Center,the Taiyuan Satellite Launch Center and the Xichang Satellite Launch Center. All the three launch centers are located in sparsely ... There are three major space launch bases in China, the Jiuquan Satellite Launch Center,the Taiyuan Satellite Launch Center and the Xichang Satellite Launch Center. All the three launch centers are located in sparsely populated areas where the terrain is even and the field of vision is broad. Security, transport conditions and the influence of the axial 展开更多
关键词 太原卫星发射中心 安全管理 交通条件 气候温度
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Microclimate regimes following gap formation in a montane secondary forest of eastern Liaoning Province, China 被引量:32
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作者 ZHU Jiao-jun TAN Hui +2 位作者 LI Feng-qin CHEN Mei ZHANG Jin-xin 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第3期167-173,共7页
In order to improve the understanding of the role of a canopy opening/gap on the physical environments in a secondary forest in Northeastern China, a case study was conducted in and around a small irregular gap in a m... In order to improve the understanding of the role of a canopy opening/gap on the physical environments in a secondary forest in Northeastern China, a case study was conducted in and around a small irregular gap in a montane secondary forest. The secondary forest, which was severely disturbed by human beings about 50 years ago, was dominated by Quercus mongolica and Fraxinus rhynchophyllaan. Temporal variation in photosynthetic photon flux density (PPFD), air temperature (TA) at 10 cm above the ground, soil temperature (Ts) and soil water content (SWC) at top-layer (0-15 cm) and sub-layer (15-30 cm) were measured from May to September after the second year since the formation of the small gap (the ratios of gap diameter to stand height were less than 0.5) in 2006 respectively. Results indicated that the highest value of PPFD occurred at the northern edge of the gap, particularly at the beginning of the growing season in May. On sunny days, the highest value of PPFD appeared earlier than that on overcast days. Maximum and mean values of TAwere higher in the northern part of the gap, and the minimum values of TAwere at the southern edge of the gap. Soil temperature varied obviously in the gap with the range from 1 to 8 ℃. Maximum values of Ts occurred at the northern part of the gap, which was significantly correlated with the maximum values of TA (R = 0.735, P〈0.05). SWC was higher in the top-layer (0-15 cm) than that in sub-layer (15-30 cm), but the difference of them was not significant (p〉0.05), which might be attributed to the small gap size and the effects of aboveground vegetations. From these results, the maximum of PPFD in the study area occurred at the northern part of the gap, which was consistent with the results observed in north hemisphere, but the occurrence time varied with the differences of the latitudes. The highest values of air and soil temperatures also occurred in the northern part of the gap because they were affected by the radiation. However, the variation of temperature in July was different from other months due to the influence of gap size. And the values of soil water content were neither higher in the gap in the wet season nor lower in the dry season, which might be affected by the gap size and topography the gap located. The variations of light, soil and air temperatures, and soil moisture in this small irregular gap might be related to the effects of the micro-site, which affects the regeneration of plant species. 展开更多
关键词 Forest gap MICROCLIMATE PPFD Temperature Soil moisture
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CLIMATIC FEATURES OF SUMMER TEMPERATURE IN NORTHEAST CHINA UNDER WARMING BACKGROUND 被引量:6
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作者 LI Ji GONG Qiang ZHAO Lian-wei 《Chinese Geographical Science》 SCIE CSCD 2005年第4期337-342,共6页
By using,summer temperature data in 26 stations from 1951 to 2003, the variation characteristics of summer temperature in Northeast China (NET) were analyzed based on the background of climate wanning. The results s... By using,summer temperature data in 26 stations from 1951 to 2003, the variation characteristics of summer temperature in Northeast China (NET) were analyzed based on the background of climate wanning. The results showed that the warming in summer was 0.15~C/10a in Northeast China, which was higher than that on the global, Northern Hemisphere or Northeast Asia scale in the recent 50 years. The responses of NET to global warming were shown in 3 aspects mainly. Firstly, it became warm and the average temperature increased in summer; secondly, the temperature variability increased, which displayed the increase of climatic instability; thirdly, the disaster of low temperature decreased and high temperature damage increased obviously, but the disaster of low temperature still existed in some areas under global warming background, which would be worthy of notice further. 展开更多
关键词 Northeast China summer temperature climate features global warming disaster of low temperature
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Trends in Monthly Temperature and Precipitation Extremes in the Zhujiang River Basin,South China(1961-2007) 被引量:6
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作者 Thomas Fischer Marco Gemmer +1 位作者 Lliu Liu Buda Su 《Advances in Climate Change Research》 SCIE 2010年第2期63-70,共8页
Monthly temperature and precipitation time-series for the Zhujiang River Basin are analyzed in order to identify changes in climate extremes. Daily temperature and precipitation data from 1961 to 2007 of 192 meteorolo... Monthly temperature and precipitation time-series for the Zhujiang River Basin are analyzed in order to identify changes in climate extremes. Daily temperature and precipitation data from 1961 to 2007 of 192 meteorological stations are used. Two temperature indicators (monthly mean and monthly maximum mean) and three precipitation indicators (monthly total, monthly maximum consecutive 5-day precipitation, and monthly dry days) are analyzed. Tendencies in all five indicators can be observed. Many stations show significant positive trends (above the 90% confidence level) for monthly mean temperatures and monthly maximum mean temperatures. For all months, a significant increase in temperature from 1961 to 2007 can be observed in the entire basin with the coastal area in particular. Positive trends of precipitation extremes can be observed from January to March. Negative trends are detected from September to November. The number of dry days in October increased significantly at 40% of all meteorological stations. Stations with changes of monthly precipitation extremes are scattered over the Zhujiang River Basin. An aggregation of heat waves and droughts can be detected which is accompanied by significant increases of temperature extremes and the negative tendencies in precipitation extremes. The detection of tendencies in climate station density. extremes essentially relies on a good data quality and high 展开更多
关键词 temperature PRECIPITATION EXTREMES Zhujiang River Basin China
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A PRIMARY STUDY OF SUMMER MONSOON INDEX OVER THE SOUTH CHINA SEA AND EAST ASIA BASED ON SATELLITE OBSERVATION 被引量:3
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作者 江吉喜 覃丹宇 刘春霞 《Journal of Tropical Meteorology》 SCIE 2007年第1期21-24,共4页
The results by statistical analysis of black body Temperature (TBB) pentad mean from the Japanese GMS in the period of May to August, 1980-2002, show that the summer monsoon index (SMI) is defined to be the pentad... The results by statistical analysis of black body Temperature (TBB) pentad mean from the Japanese GMS in the period of May to August, 1980-2002, show that the summer monsoon index (SMI) is defined to be the pentad mean TBB≤273 K. Its intensity includes three levels: TBB〉268 K for weak monsoon, 268 KETBB〉263 K for normal monsoon and TBB≤263K for strong monsoon over the South China sea and East Asia. In the meantime, a diagnostic method using TBB pentad anomaly is also introduced to help identify monsoon intensity. The SMI is used to run statistical analyses of the initial onset of the monsoon and its pentad variations with the year and month. A fairly close relationship is found between pentad monsoon activity and heavy rainfall periods in the two typical flood years of 1994 and 1998, which resulted from heavy rainfall over the Yangtze River basin and south China. 展开更多
关键词 pentad summer monsoon index black-body temperature (TBB) monsoon intensity
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Characteristics of Extreme Temperature Event and Its Response to Regional Warming in Northwest China in Past 45 Years 被引量:17
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作者 YANG Jinhu REN Chuanyou JIANG Zhihong 《Chinese Geographical Science》 SCIE CSCD 2008年第1期70-76,共7页
Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesim... Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesimal method for different stations at first,then yearly EHT and ELT events were counted up in differ-ent stations,and the characteristics of their spatio-temporal distribution were diagnosed at last.The study drew follow-ing conclusions:1)The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China.2)The spatial distribution of the EHT and ELT events can be divided into five sub-regions,namely,the north of Qinghai and west of Gansu,the north of Xinjiang,the south of Xinjiang,the east of Northwest China and the south of Qinghai.3)The EHT events showed remarkable increasing trend in all of five sub-regions,but only in the north of Qinghai and west of Gansu area,sudden change phenomenon occurred;the ELT events showed decreasing trend in all of five sub-regions,and sudden change phenomenon occurred in Northwest China except for south of Qinghai.4)In all of five sub-regions the EHT events showed remarkable 12-14yr period os-cillation,and the ELT event showed significant 13-15yr and 7-8yr period oscillation.5)The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively. 展开更多
关键词 extreme temperature response to warming Northwest China
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Changes in Daily Climate Extremes of Observed Temperature and Precipitation in China 被引量:15
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作者 WANG Ai-Hui FU Jian-Jian 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期312-319,共8页
Daily precipitation for 1960-2011 and maximum/minimum temperature extremes for 1960-2008 recorded at 549 stations in China are utilized to investigate climate extreme variations.A set of indices is derived and analyze... Daily precipitation for 1960-2011 and maximum/minimum temperature extremes for 1960-2008 recorded at 549 stations in China are utilized to investigate climate extreme variations.A set of indices is derived and analyzed with a main focus on the trends and variabilities of daily extreme occurrences.Results show significant increases in daily extreme warm temperatures and decreases in daily extreme cold temperatures,defined as the number of days in which daily maximum temperature (Tmax) and daily minimum temperature (Tmin) are greater than the 90th percentile and less than thel0th percentile,respectively.Generally,the trend magnitudes are larger in indices derived from Tmin than those from Tmax.Trends of percentile-based precipitation indices show distinct spatial patterns with increases in heavy precipitation events,defined as the top 95th percentile of daily precipitation,in westem and northeastern China and in the low reaches of the Yangtze River basin region,and slight decreases in other areas.Light precipitation,defined as the tail of the 5th percentile of daily precipitation,however,decreases in most areas.The annual maximum consecutive dry days (CDD) show an increasing trend in southem China and the middle-low reach of the Yellow River basin,while the annual maximum consecutive wet days (CWD) displays a downtrend over most regions except western China.These indices vary significantly with regions and seasons.Overall,occurrences of extreme events in China are more frequent,particularly the night time extreme temperature,and landmasses in China become warmer and wetter. 展开更多
关键词 climate extremes temperature RAIN maximum dry/wet days
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Implications of Climate Change on Streamflow of a Snow-Fed River System of the Northwest Himalaya 被引量:7
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作者 Vaibhav SHARMA Varunendra Dutta MISHRA Pawan Kumar JOSHI 《Journal of Mountain Science》 SCIE CSCD 2013年第4期574-587,共14页
Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. ... Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. The implications of air temperature trends (+0.11℃decade) reported for the entire north-west Himalaya for past century and the regional warming (+0.7℃/decade) trends of three observatories analyzed between last two decades were used for future projection of snow cover depletion and stream flow. The streamflow was simulated and validated for the year 2007-2008 using snowmelt runoff model (SRM) based on in-situ temperature and precipitation with remotely sensed snow cover area. The simulation was repeated using higher values of temperature and modified snow cover depletion curves according to the assumed future climate. Early snow cover depletion was observed in the basin in response to warmer climate. The results show that with the increase in air temperature, streamfiow pattern of Jhelum will be severely affected. Significant redistribution of streamflow was observed in both the scenarios. Higher discharge was observed during spring-summer months due to early snowmelt contribution with water deficit during monsoon months. Discharge increased by 5%-40% during the months of March to May in 2030 and 2050. The magnitude of impact of air temperature is higher in the scenario-2 based on regional warming. The inferences pertaining to change in future streamflow pattern can facilitate long term decisions and planning concerning hydro-power potential, waterresource management and flood hazard mapping in the region. 展开更多
关键词 SNOWMELT Snow cover depletion curve(SCDC) Climate change Global warming Streamflow SRM Jhelum
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CHARACTERISTICS OF CLIMATE WARMING AND IMPACT ON CLIMATE ZONES CHANGE IN GUANGDONG 被引量:1
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作者 陈新光 钱光明 +2 位作者 陈特固 李春梅 余克服 《Journal of Tropical Meteorology》 SCIE 2007年第1期61-64,共4页
Based on temperature data in Guangdong in the past 50years, statistical methods are used to analyze the characteristics of temperature in spatial and temporal variation. The results show that land surface temperature ... Based on temperature data in Guangdong in the past 50years, statistical methods are used to analyze the characteristics of temperature in spatial and temporal variation. The results show that land surface temperature warms by 0.16℃/1 0a in Guangdong. The range of warming was lower than the average of nationwide and global land surface. Furthermore, the temperature has a larger increase tendency in winter and spring and coastal areas than in summer and autumn and inland areas. Climate zones move towards the north obviously. North tropical zone is expanding, south subtropical zone is reducing and central subtropical zone is relatively stable. Under the global climate warming, characteristics of climate warming in Guangdong were influenced by atmosphere general circulation, sea surface temperature and human activities etc. 展开更多
关键词 climate warming displacement of climate zones Guangdong province
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