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Changing Trends of Daily Temperature Extremes with Different Intensities in China 被引量:1
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作者 王遵娅 丁一汇 +1 位作者 张强 宋亚芳 《Acta meteorologica Sinica》 SCIE 2012年第4期399-409,共11页
By comparing two sets of quality-controlled daily temperature observation data with and without the inhomogeneity test and adjustment from 654 stations in China during 1956 2004 and 1956-2010, impacts of inhomogeneity... By comparing two sets of quality-controlled daily temperature observation data with and without the inhomogeneity test and adjustment from 654 stations in China during 1956 2004 and 1956-2010, impacts of inhomogeneity on changing trends of four percentile temperature extreme indices, including occurrences of cold days, cold nights, warm days, and warm nights with varying intensities, were discussed. It is found that the inhomogeneity affected the long-term trends averaged over extensive regions limitedly. In order to minimize the inhomogeneity impact, the 83 stations identified with obvious inhomogeneity impacts were removed, and an updated analysis of changing trends of the four temperature extreme indices with varying intensities during 1956 2010 was conducted. The results show that annual occurrences of both cold nights and cold days decreased greatly while those of warm nights and warm days increased significantly during the recent 20 years. The more extreme the event is, the greater the magnitude of changing trends for the temperature extreme index is. An obvious increasing trend was observed in annual occurrences of cold days and cold nights in the recent four years. The magnitude of changing trends of warm extreme indices was greater than that of cold extreme indices, and it was greater in northern China than in southern China. Trends for summer occurrence of cold days were not significant. Decreasing trends of occurrences of both cold nights and cold days were the greatest in December, January, and February (DJF) but the least in June, July, and August (JJA), while increasing trends of warm nights were the greatest in JJA. Cold nights significantly decreased from 1956 to 1990, and then the decreasing trend considerably weakened. The decreasing trend also showed an obvious slowdown in recent years for occurrence of cold days. However, increasing trends of warm nights and warm days both have been accelerated continuously since the recent decades. Further analysis presents that the evolution of the trends for occurrences of the four temperature extreme indices was dominated by the changes in northern China . 展开更多
关键词 temperature extremes cold nights cold days warm nights warm days changing trend
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Analysis of Changing Characteristics and Trends of Temperature and Precipitation in Yanshi City in Recent 50 Years
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作者 Zhang Yuan 《Meteorological and Environmental Research》 CAS 2015年第10期1-4,共4页
Based on meteorological observation data of temperature and precipitation in Yanshi City from 1961 to 2010, annual and interdecadal variations of annual average temperature, annual average maximum temperature, annual ... Based on meteorological observation data of temperature and precipitation in Yanshi City from 1961 to 2010, annual and interdecadal variations of annual average temperature, annual average maximum temperature, annual average minimum temperature, and annual average pre- cipitation in Yanshi City in recent 50 years were analyzed, and then M-K test of changing trend of annual average temperature was conducted. The results showed that from 1961 to 2010, annual average temperature, annual average maximum temperature and annual average minimum tempera- ture showed a significantly increasing trend in Yanshi City, rising by 0.30, 0.20 and 0.50 ~(3/10 a respectively. Annual average temperature was the lowest in the 1970s and the highest in 2000 -2010. There was a sudden change in annual average temperature in 1995. In the 50 years, annual av- erage precipitation in Yanshi City increased by 1.8 mm/10 a, but the increase was not significant. The minimum of annual average precipitation 511.3 mm appeared in the 1960s, while the maximum 553.2 mm appeared in 2000 -2010. 展开更多
关键词 Temperature changing trend PRECIPITATION M-K test Yanshi City China
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The Trends of Globalization and Digitalization are Changing the Market Contexts
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作者 Sunil Bharti Mittal 《China's Foreign Trade》 2016年第5期20-21,共2页
We know that SME’s that trade online grow faster and create more jobs than those that only operate in their domestic markets.The Internet is breaking down many traditional barriers to global trade,but there is still ... We know that SME’s that trade online grow faster and create more jobs than those that only operate in their domestic markets.The Internet is breaking down many traditional barriers to global trade,but there is still much governments can do to speed and enable SME digitization and ecommerce.The opportunity is huge at 展开更多
关键词 The trends of Globalization and Digitalization are changing the Market Contexts
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Changes of coastline and tidal flat and its implication for ecological protection under human activities: Take China’s Bohai Bay as an example
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作者 Yong Li Ming-zheng Wen +3 位作者 Heng Yu Peng Yang Fei-cui Wang Fu Wang 《China Geology》 CAS CSCD 2024年第1期26-35,共10页
The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecologic... The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecological environment changes and even global changes.Based on field measurements,combined with Linear Regression(LR)model and Inverse Distance Weighing(IDW)method,this paper presents detailed analysis on the change history and trend of the shoreline and tidal flat in Bohai Bay.The shoreline faces a high erosion chance under the action of natural factors,while the tidal flat faces a different erosion and deposition patterns in Bohai Bay due to the impact of human activities.The implication of change rule for ecological protection and recovery is also discussed.Measures should be taken to protect the coastal ecological environment.The models used in this paper show a high correlation coefficient between observed and modeling data,which means that this method can be used to predict the changing trend of shoreline and tidal flat.The research results of present study can provide scientific supports for future coastal protection and management. 展开更多
关键词 SHORELINE Tidal flat Erosion deposition patterns changing trend Ecological protection Human activity Linear regression model Inverse distance weighing method Prediction Bohai Bay
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气候变化对青藏高原河流源区径流的影响
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作者 Zhenxin Bao Jianyun Zhang +6 位作者 Yanqing Lian Guoqing Wang Junliang Jin Zhongrui Ning Jiapeng Zhang Yanli Liu Xiaojun Wang 《Engineering》 SCIE EI CAS CSCD 2024年第3期133-142,共10页
The Tibetan Plateau(TP)is the headwater of the Yangtze,Yellow,and the transboundary Yarlung Zangbo,Lancang,and Nujiang Rivers,providing essential and pristine freshwater to around 1.6 billion people in Southeast and S... The Tibetan Plateau(TP)is the headwater of the Yangtze,Yellow,and the transboundary Yarlung Zangbo,Lancang,and Nujiang Rivers,providing essential and pristine freshwater to around 1.6 billion people in Southeast and South Asia.However,the temperature rise TP has experienced is almost three times that of the global warming rate.The rising temperature has resulted in glacier retreat,snow cover reduction,permafrost layer thawing,and so forth.Here we show,based on the longest observed streamflow data available for the region so far,that changing climatic conditions in the TP already had significant impacts on the streamflow in the headwater basins in the area.Our analysis indicated that the annual average temperature in the headwater basins of these five major rivers has been rising on a trend averaging 0.38℃-decade^(-1) since 1998,almost triple the rate before 1998,and the change of streamflow has been predominantly impacted by precipitation in these headwater basins.As a result,streamflow in the Yangtze,Yarlung Zangbo,Lancang,and Nujiang River headwater areas is on a decreasing trend with a reduction of flow ranging from 3.0-10^(9)-5.9-10^(9) m^(3)·decade^(-1)(-9.12%to-16.89%per decade)since 1998.The increased precipitation in the Tangnahai(TNH)and Lanzhou(LZ)Basins contributed to the increase of their streamflows at 8.04%and 14.29%per decade,respectively.Although the increased streamflow in the headwater basins of the Yellow River may ease some of the water resources concerns,the decreasing trend of streamflow in the headwater areas of the southeastern TP region since 1998 could lead to a water crisis in transboundary river basins for billions of people in Southeast and South Asia. 展开更多
关键词 Tibetan Plateau Streamflow Change trend Climate change
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Child Malnutrition In China-Present Status and Changing Trend 被引量:1
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作者 CHANG YING XIAN ZU-DE +3 位作者 HE WU CHANG SU-YING MA HAI-JIANG AND CHEN CHUN-MING(Institute of Nutrition and Food Hygiene, 29 Nan Wei Road Beijing 100050, China, State Statistics Bureau, Beijing, China,Chinese Academy of Preventive Medicine,27 Nan Wei Road Bei 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1996年第2期164-180,共17页
Halving the malnutrition of under five of years has been set as one of the goals to be achieved by the year of 2000 by Chinese government. So it is important to know the present status of child malnutrition and its tr... Halving the malnutrition of under five of years has been set as one of the goals to be achieved by the year of 2000 by Chinese government. So it is important to know the present status of child malnutrition and its trend of changing, in order to predict the possible outcome of the achievement of the goal. According to the Child Survey carried out by the State Statistic Bureau (SSB) in 26 provinces and autonmous regions and 3 municipalities in 1992, the prevalence of malnutrition of under five was: moderate and severe underweight, stunting and wasting were 17.9%, 34.7% and 4.7% respectively. But there are significant differences among urban and rural children and between different provinces. The highest prevalence rate usually occurred in the second year of life of the children, and this may be the result of inadequate weaning food provided to the children. As compared with the data collected in 1987 by SSB in 9 provinces and autonomous regions, an impressive improvement in underweight has occurred within these 5 years. The average declined prevalence was 20.5%. It is specially true for urban children. To stunting, there was also improvement for urban children but not in the rural, resulting and over all increasing of prevalence by 5.9%. To wasting, the prevalence for urban children was low and remained at the same level while there was some what increase in the rural. So, according to these results, with constant economic development and more attempt made in areas and groups at risk, the goal to decrease malnutrition in half in terms of underweight could be reached by the year of 2000 展开更多
关键词 In WHO Child Malnutrition In China-Present Status and changing Trend
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Change Trends of Accumulated Temperature and Effects on Agricultural Production in Shenyang during Recent 58 Years 被引量:1
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作者 YANG Li-li LIU Feng-zhi JIANG Miao 《Meteorological and Environmental Research》 CAS 2011年第1期35-38,42,共5页
[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang... [Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution. 展开更多
关键词 Shenyang Accumulated temperature Climatic tendency Change trend China
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Variation Characteristics and Trends of Temperature and Evaporation in Huanren County in Recent 60 Years
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作者 Zhao Lei Ji Qi +1 位作者 Li Ji Wang Junchao 《Meteorological and Environmental Research》 CAS 2016年第3期7-9,共3页
Based on the data of daily average temperature and evaporation in Huanren County from 1953 to 2012, the changing characteristics and trends of temperature and evaporation were analyzed by using climatic tendency rate ... Based on the data of daily average temperature and evaporation in Huanren County from 1953 to 2012, the changing characteristics and trends of temperature and evaporation were analyzed by using climatic tendency rate and sliding Ttest method. The results showed that annual av- erage temperature in Huanren County showed a significant increasing trend in recent 60 years, and its linear tendency rate was 0.26 ℃/10 a. Tem- perature increase was in other seasons except for summer. There was a sudden change in annual average temperature in 1987, and winter average temperature changed suddenly in 1969 and 1985, while there were no sudden changes in average temperature in other seasons. Annual average evaporation also decreased, and its linear trend rate was -8.19 mm/10 a; average evaporation tended to decrease in spring and summer and in- creased in autumn and winter. In a word, the climate tended to be warm and dry in Huanren County. 展开更多
关键词 TEMPERATURE EVAPORATION changing trend Mutation detection Huanren County China
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Preliminary Studies on Evaluation and Change Trends of Dominant Components in New Types of Tobacco Sheets by Thick Pulp Process
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作者 Hao SHU Xiangbing TANG +8 位作者 Ziwei WANG Xinge ZHANG Wanxia WANG Dan LI Qunshan YAN Tongfu SU Yanqiu JING Song GAO Bin XIONG 《Agricultural Biotechnology》 CAS 2022年第6期126-129,133,共5页
[Objectives]This study was conducted to deeply understand the effects of production process on the quality of new types of tobacco sheets with different flavors.[Methods]Based on the pilot production process of thick ... [Objectives]This study was conducted to deeply understand the effects of production process on the quality of new types of tobacco sheets with different flavors.[Methods]Based on the pilot production process of thick pulp method,four different flavors of tobacco sheets were sampled at several links in the production process,for the detection of the contents of the main components in the samples,including propylene glycol,glycerol,menthol and glyceryl triacetate,so as to explore the change trends of various components in the thick pulp process.[Results]The change laws of propylene glycol and glycerol contents had a very high similarity,showing a trend of first decreasing and increasing then.The changes of menthol content and glyceryl triacetate content were greatly affected by the specific flavor formula.As one of the indexes of the new tobacco evaluation system,the alcohol-to-ester ratio data need to be further improved in the actual production and application process.[Conclusions]This study provides basic data support for improving the quality of tobacco sheets. 展开更多
关键词 New tobacco product Thick pulp process Heat-not-burn tobacco product Tobacco sheets changing trend
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The Influence of the Changes in Social Trends of Thought in Japan
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作者 Cui Shiguang is a Research Professor at Institute for Japanese Studies of China Academy of Social Sciences. 《Contemporary International Relations》 2003年第11期33-38,共6页
The social trend of thought is the trend of thought that is of extensive influence formed in a certain period of time in a given society. It o-riginates from the changes in international environment and domestic socia... The social trend of thought is the trend of thought that is of extensive influence formed in a certain period of time in a given society. It o-riginates from the changes in international environment and domestic social situation, reflecting the interests and demands of a given group of people and producing a great influence on the foreign and domestic policies and the future trend of the society. One prominent feature of 展开更多
关键词 of in The Influence of the Changes in Social trends of Thought in Japan that
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A Changing India and Its Trend
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作者 Dao Shulin Su Jingxiang Hu Shisheng Fu Xiaoqiang Ma Jiali Zhang Siqi 《Contemporary International Relations》 2004年第7期1-1,共1页
关键词 A changing India and Its Trend
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Correlation analysis between the Aral Sea shrinkage and the Amu Darya River 被引量:1
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作者 WANG Min CHEN Xi +6 位作者 CAO Liangzhong KURBAN Alishir SHI Haiyang WU Nannan EZIZ Anwar YUAN Xiuliang Philippe DE MAEYER 《Journal of Arid Land》 SCIE CSCD 2023年第7期757-778,共22页
The shrinkage of the Aral Sea,which is closely related to the Amu Darya River,strongly affects the sustainability of the local natural ecosystem,agricultural production,and human well-being.In this study,we used the B... The shrinkage of the Aral Sea,which is closely related to the Amu Darya River,strongly affects the sustainability of the local natural ecosystem,agricultural production,and human well-being.In this study,we used the Bayesian Estimator of Abrupt change,Seasonal change,and Trend(BEAST)model to detect the historical change points in the variation of the Aral Sea and the Amu Darya River and analyse the causes of the Aral Sea shrinkage during the 1950–2016 period.Further,we applied multifractal detrend cross-correlation analysis(MF-DCCA)and quantitative analysis to investigate the responses of the Aral Sea to the runoff in the Amu Darya River,which is the main source of recharge to the Aral Sea.Our results showed that two significant trend change points in the water volume change of the Aral Sea occurred,in 1961 and 1974.Before 1961,the water volume in the Aral Sea was stable,after which it began to shrink,with a shrinkage rate fluctuating around 15.21 km3/a.After 1974,the water volume of the Aral Sea decreased substantially at a rate of up to 48.97 km3/a,which was the highest value recorded in this study.In addition,although the response of the Aral Sea's water volume to its recharge runoff demonstrated a complex non-linear relationship,the replenishment of the Aral Sea by the runoff in the lower reaches of the Amu Darya River was identified as the dominant factor affecting the Aral Sea shrinkage.Based on the scenario analyses,we concluded that it is possible to slow down the retreat of the Aral Sea and restore its ecosystem by increasing the efficiency of agricultural water use,decreasing agricultural water use in the middle and lower reaches,reducing ineffective evaporation from reservoirs and wetlands,and increasing the water coming from the lower reaches of the Amu Darya River to the 1961–1973 level.These measures would maintain and stabilise the water area and water volume of the Aral Sea in a state of ecological restoration.Therefore,this study focuses on how human consumption of recharge runoff affects the Aral Sea and provides scientific perspective on its ecological conservation and sustainable development. 展开更多
关键词 Aral Sea shrinkage recharge runoff Amu Darya River Syr Darya River multifractal detrend cross-correlation analysis(MF-DCCA) Bayesian Estimator of Abrupt change Seasonal change and Trend(BEAST) Central Asia
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Age Structure and Change Trend of Tobacco Farmers:A Case Study of Shashi Town,Liuyang City,Hunan Province
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作者 Jianwen WANG Liangjiao LIU +3 位作者 Zhengguang ZHAI Zhiqiang DENG Tao ZHU Sihan HUANG 《Asian Agricultural Research》 2023年第8期8-15,共8页
Taking the tobacco-growing area of Shashi Town,Liuyang City as the object,the number of registered,newly added and resigned tobacco farmers in each year,average age,number and proportion of tobacco farmers of differen... Taking the tobacco-growing area of Shashi Town,Liuyang City as the object,the number of registered,newly added and resigned tobacco farmers in each year,average age,number and proportion of tobacco farmers of different ages,number and proportion of tobacco farmers born in different eras,as well as planting scale and planting history of flue-cured tobacco in the last 10 years were analyzed statistically.The results showed that the number of tobacco farmers in Shashi Town showed a rapid decline trend from 2012 to 2018,while the average age continuously increased,and the average planting scale rose in a wave like way.From 2019 to 2021,the decline rate of the number of tobacco farmers slowed down,and the average planting scale continuously increased,while the aging of tobacco farmers accelerated.Meantime,the birth years of tobacco farmers were further concentrated in the 1960s,and they were mainly at the age of 50-59.The tobacco industry in Shashi Town of Liuyang City is facing the crisis of aging tobacco farmers and no successor of flue-cured tobacco planting,and it is predicted that the next 5-10 years will continue the change trend from 2019 to 2021. 展开更多
关键词 Tobacco farmers Number Birth year Average age Planting years Change trend Prediction
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怒江流域近30年太阳总辐射变化趋势(英文) 被引量:1
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作者 石磊 杜军 《Meteorological and Environmental Research》 CAS 2010年第7期38-40,44,共4页
Based on the data of sunshine duration,cloud cover and relative humidity from 9 stations in 1981-2008,the spatial and temporal distribution and change trend of total solar radiation in river valley basin of Nujiang we... Based on the data of sunshine duration,cloud cover and relative humidity from 9 stations in 1981-2008,the spatial and temporal distribution and change trend of total solar radiation in river valley basin of Nujiang were analyzed,as well as its impact factors.The results showed that annual solar radiation decreased obviously in Nujiang basin from 1981 to 1997,with the rate of-161.1 MJ/(m2·10 a),while it went up after 1997 at the rate of 111.3 MJ/(m2·10 a).Annual total cloud cover showed significant decrease trend with the rate of 1.8%/10 a,but annual low cloud cover increased at the rate of 3.2%/10 a.Contrary to the change trend of annual solar radiation,relative humidity rose at the increase of 3.1%/10 a from 1981 to 1997 and decreased significantly at the rate of 5.6%/10 a in 1997-2008.The change of water vapor pressure was consistent with relative humility change.Low cloud cover was the main impact factor of total solar radiation and had a negative correlation with total solar radiation. 展开更多
关键词 Nujiang basin Total solar radiation Change trend Impact factor China
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Climate change trend and its effects on reference evapotranspiration at Linhe Station, Hetao Irrigation District 被引量:5
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作者 Xu-ming WANG Hai-jun LIU +1 位作者 Li-wei ZHANG Rui-hao ZHANG 《Water Science and Engineering》 EI CAS CSCD 2014年第3期250-266,共17页
Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference e... Linhe National Meteorological Station, a representative weather station in the Hetao Irrigation District of China, was selected as the research site for the present study. Changes in climatic variables and reference evapotranspiration (ET0 ) (estimated by the Penman-Monteith method) were detected using Mann-Kendall tests and Sen's slope estimator, respectively. The authors analyzed the relationship between the ET0 change and each climatic variable's change. From 1954 to 2012, the air temperature showed a significant increasing trend, whereas relative humidity and wind speed decreased dramatically. These changes resulted in a slight increase in ETo. The radiative component of total ET0 increased from 50% to 57%, indicating that this component made a greater contribution to the increase in total ETo than the aerodynamic component, especially during the crop growing season (from April to October). The sensitivity analysis showed that ETo in Hetao is most sensitive to mean daily air temperature (11.8%), followed by wind speed (-7.3%) and relative humidity (4.8%). Changes in sunshine duration had only a minor effect on ET0 over the past 59 years. 展开更多
关键词 climatic variables reference evapotranspiration change trend Mann-Kendall test sensitivity analysis
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Study on the Variation Characteristic of Precipitation in Liaoning Province in Recent 48 Years 被引量:4
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作者 ZHANG Hai-na GAO Jie 《Meteorological and Environmental Research》 CAS 2011年第1期5-6,共2页
[Objective] The aim was to study the variation characteristic of precipitation in Liaoning Province in recent 48 years. [Method] According to monthly precipitation data from meteorological observation station in Liaon... [Objective] The aim was to study the variation characteristic of precipitation in Liaoning Province in recent 48 years. [Method] According to monthly precipitation data from meteorological observation station in Liaoning Province from 1961 to 2008, the variation characteristic of precipitation in Liaoning was analyzed by means of one-dimensional linear estimation, 5-year moving average and wavelet transform method in our paper. [Result] Annual mean precipitation in Liaoning from 1961 to 2008 showed decrease trend on the whole, and there was great difference in variation in each season; there was more rainfall in 1960s, 1970s and 1990s and less rainfall in 1980s; spring precipitation showed increase trend on the whole, with great annual variation, while precipitation in other seasons reduced; the main fluctuation period of precipitation was 7-9 years which included the shorter variation period of 2-3 years. [Conclusion] The study could provide scientific references for the rational utilization of water resources, disaster prevention and reduction in Liaoning Province. 展开更多
关键词 PRECIPITATION Change trend Characteristic analysis China
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Trend of Salt Lake Changes in the Background of Global Warming and Tactics for Adaptation to the Changes 被引量:12
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作者 ZHENGMianping QIWen +2 位作者 JIANGXianfeng ZHAOYuanyi LIMinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期795-807,共13页
Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the auth... Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the authors explain how geological hazards in salt lake areas are caused by natural agents and how humans can seek benefits, avoid hazards and reduce losses on the premise that they have monitored and mastered the trend of salt lake changes in advance and even can store flood and recharge water in lakes and extract saline resources. The climate in western China is probably turning from warm-dry to warm-moist. The authors analyze the change trend of salt lakes sensu lato (with salinity≥0.3 wt% (NaCl)eq) and salt lakes sensu stricto (with salinity ≥3.5 wt% (NaCl)eq) in China in such climatic conditions and distinguish three types of salt lake areas (i.e. lake water rising type, lake water falling type and lake water rising and unstable type) according to the characteristics of lake water rising and shrinking. In order to conform to the climatic and lake changes in China's salt lake areas, the authors propose to add and improve hydrological and meteorological observation stations and integrate observations with remote sensing monitoring in important salt lake areas and set up multidisciplinary and interdepartmental basic projects to monitor and study recent climatic and environmental changes in salt lake areas of western China. Moreover, it is necessary to build additional flood-control and drought-preventing water conservancy facilities in key salt lake areas and work out measures for ecological protection in salt lake areas. Full consideration should be given to the influence of flooding when building saltfields and implementing capital projects. 展开更多
关键词 global warming geological hazard of salt lake trend of salt lake change salt lake water rising and shrinking types tactics for adaptation to change
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Evaluation matrix with the speed feature based on double inspiriting control lines 被引量:1
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作者 Weiwei Liu Chunsheng Shi Jing Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期962-970,共9页
Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to re... Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to remedy this deficiency. Firstly, the change speed state (CSS) of the evaluated objects is analyzed based on double inspiriting control lines (DICLs), and a matrix of the CSS is constructed. Then, 72 elements in the matrix are analyzed, and formulas describing each CSS are given. The efficiency of the proposed evaluation matrix is proved when the CSS merges with the change speed trend (CST) in the dynamic comprehensive evaluation. Finally, a computing example shows that the proposed evaluation matrix is feasible in the dynamic comprehensive evaluation with the speed feature. 展开更多
关键词 double inspiriting control lines (DICLs) change speed state (CSS) change speed trend (CST) evaluation matrix
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Analyses of spring mean circulations for major andminor dust storm years in China-Mongolia area 被引量:3
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作者 MinHong Song 1,ZhengAn Qian 1,Ying Cai 1,ChungMing Liu 2 1.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China.2.Department of Atmospheric Sciences,Taiwan University,Taipei 106,China. 《Research in Cold and Arid Regions》 2009年第4期361-371,共11页
To better understand the dust storm (hereafter DS) inducing circulation in the China-Mongolia (CM) DS activity area,the spring mean circulation features and differences on lower levels in three subregions of the CM DS... To better understand the dust storm (hereafter DS) inducing circulation in the China-Mongolia (CM) DS activity area,the spring mean circulation features and differences on lower levels in three subregions of the CM DS area for the majorandminor-DS years have,as a whole (not partly),been analyzed,utilizing the National Centers for Environmental Prediction and the National Center for Atmospheric Research (NCEP/NCAR) reanalyzed gridded data,the observed DS frequency data in the CM area,and the composite analysis method.The main conclusions are as follows:(1) Judging from the differences in the DS-inducing systems,dust origins,paths of invading cold air,and main DS-strike areas,the whole CM DS area is roughly divided into the three subre-gions:the East-,Middleand West-CM subregions (in this paper,referred to as E-,M-,and W-CM).(2) In major DSs during spring over the E-CM,the middleand lower-level troughs or cyclones over the Japan Sea and northeastern China (NEC) domi-nate.The invading cold air along the northeastern (NE) or north by east (NE) path often causes the DS in the E-CM region.But nearly the opposite is true inminor DS during spring in E-CM.(3) In the major DS during spring over the M-CM region,the Mongolian troughs or cyclones are the main DS-inducing systems.The strong invading cold air along the northwestern (NW)or north by west (Nw) path causes the DSs in the M-CM region.(4) In the major DSs during spring over the W-CM region,the South Xinjiang heat lows prevail,the intruding cold air has a western path,and creates the DSs in South Xinjiang.(5) In the past 50 years,the DSs over the M-CM region have had the most severe impact on the preceding three subregions of the CM DS area.Overall,DS activities over all of three regions of the CM area decreased in the past (particularly,over Mand W-CM regions since the mid-1980s.But there existed a short and sudden increasing in E-CM in the years 2000-2002.(6) It is circulation changes and desertification evolutions that cause the yearly and decadal changes of DS in CM area,especially the former.With the backdrop of global warming in the future,perhaps the decreased DS activities over Mand W-CM will persist for some time again,and special attention should be paid to ones over E-CM or to the individual DS events over Mand W-CM. 展开更多
关键词 East- middleand west-CM subregions major andminor DS during spring DS-inducing system path of invading cold air trend of DS activity changes
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Characteristics of Ambient Air Quality in the Central Urban Area of Western Guizhou in the Past Five Years 被引量:1
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作者 Shihua JIANG Zaixiang CHI +3 位作者 Kai XU Lijuan LIU Zijiang YANG Changwen CHEN 《Meteorological and Environmental Research》 CAS 2020年第6期23-30,共8页
Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become... Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become one of the main problems that endanger human health and restrict economic development,which has been widely concerned.In this paper,the air quality status and its changing trend were analyzed by using the methods of the comprehensive index of ambient air quality and Spearman s rank correlation coefficient,based on the hourly pollutant concentration data of five national ambient air quality monitoring stations in the central urban area of Liupanshui City,Guizhou Province from January 1,2015 to December 31,2019.The results showed that the concentration of air pollutants in the atmosphere in the past five years showed a downward trend in the central urban area of Liupanshui City.During 2018-2019,the air quality has been up to the standard for two consecutive years,and it was developing to a higher quality direction.The air quality was better in summer half year than in winter half year.In one year,the air quality was the best in June and the worst in February.The air quality was the best at 07:00 and the worst at 21:00 every day.The air quality in the east and the west of the city was better than that in the middle.In most years,the activities,making and burning paper to resemble money as an offering sacrifices to gods or ancestors in Zhongyuan Festival,caused serious pollution. 展开更多
关键词 Air quality Pollution concentration Spearman s rank correlation coefficient Change trends
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