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1.
郭雪 《山西气象》2011,(3):19-22
利用太原市1951年-2010年的实测气象资料,采用线性趋势分析、累计距平、Mann—Kendall方法,分析了太原市年均气温、平均最高气温、平均最低气温、02时平均气温、14时平均气温的变化趋势。得出了太原市总体上呈现增暖趋势,从1977年开始出现了显著增温;夜间气温增温幅度高于白天增温幅度,冬季增温幅度高于夏季增温幅度;最低平均气温的增温幅度最大等结论。  相似文献   

2.
潮州市近53年气温变化特征   总被引:3,自引:0,他引:3  
利用潮州市饶平地面气象观测站1956—2008年气温观测资料,运用线性倾向估计、Mann-Kendal突变检验、小波分析和累积距平等分析方法对近53年来温度变化的主要特征进行分析。结果表明,近53年来平均气温呈增加趋势,线性增温速率0.17℃/10a,突变点在1994年,其主振荡周期的时间尺度为18年;季节温度变化最显著特点为冬季增温最明显,突变出现时间最早,在1987年,其次是秋季、夏季,最后是春季,突变点在1994、1995年附近;据季节温度振荡主周期判断,在大的时间尺度上各季节目前均处于偏暖期,但较小尺度上(2~4年),夏、秋季目前处于偏暖期,冬、春季处于偏冷期;1990年至今,大于等于0℃、10℃的活动积温处于回升阶段。  相似文献   

3.
Summary In this study, trends of annual and seasonal surface air temperature time series were examined for 20 stations in Greece for the period 1955–2001, and satellite data for the period 1980–2001. Two statistical tests based on the least square method and one based on the Mann-Kendall test, which is also capable of detecting the starting year of possible climatic discontinuities or changes, were used for the analysis. Greece, in general, shows a cooling trend in winter for the period 1955–2001, whereas, summer shows an overall warming trend, however, neither is statistically significant. As a result, the overall trend of the annual values is nearly zero. Comparison with corresponding trends in the Northern Hemisphere (NH) shows that temperatures in Greece do not follow the intense warming trends. Satellite data indicate a remarkable warming trend in mean annual, winter and summer in Greece for the period 1980–2001, and a slight warming trend in annual, spring and autumn for the NH. Comparison with the respective trends detected in the surface air temperature for the same period (1980–2001) shows they match each other quite well in both Greece and the NH. The relationship between temperature variability in Greece and atmospheric circulation was also examined using correlation analysis with three circulation indices: the well-known North Atlantic Oscillation Index (NAOI), a Mediterranean Oscillation Index (MOI) and a new Mediterranean Circulation Index (MCI). The MOI and MCI indices show the most interesting correlation with winter temperatures in Greece. The behaviour of pressure and the height of the 500hPa surface over the Mediterranean region supports these results.  相似文献   

4.
赤峰地区近50a气候变化诊断分析   总被引:2,自引:1,他引:1  
利用线性回归、累积距平和多项式回归法,对赤峰地区1951—1990年12个气象台站的月、季、年平均气温、最高气温、最低气温序列进行连续性变化趋势分析,确定该区域的气候变化趋势。应用Mann-Kendall法和滑动t检验法检验气温序列变化的不连续性,确定突变时间。结果表明:赤峰地区12个月的平均气温均有升温趋势,增温幅度从0.56℃/10a到0.15℃/10a,其中2月份最强。季节增温最显著的是冬季,其次是秋季和春季,夏季最弱。年平均气温增温率是0.28℃/10a,1988年是变暖的第一年,突变时间在1993年;年平均最低气温增温率是0.29℃/10a,1988年是变暖的第一年,突变时间在1988年;年平均最高气温增温率是0.26℃/10a,1993年是变暖的第一年,突变时间在1993—1996年附近;平均最低气温和最高气温的变暖时间具有不对称性。  相似文献   

5.
近60a来洞庭湖区气温的变化特征   总被引:2,自引:1,他引:1  
以洞庭湖区24个气象站1952-2010年的平均气温资料为基础,利用气候倾向率、Mann-Kendall突变检验法和小波分析等方法,分析了洞庭湖区的气温变化特征.结果表明:洞庭湖区年平均、冬季、春季和秋季气温均呈显著上升趋势,增温速率尤以冬季和春季为甚.除夏季外,年平均和其他各季气温在1990s,先后发生增温性突变.高温日数呈上升趋势,但显著性不明显,低温日数下降趋势非常显著.除夏季外,年平均和各季异常冷年,基本出现在1950s至1970s,异常暖年,均出现在1998年以后.除夏季外,各季气温均存在准9a周期.  相似文献   

6.
气候变暖背景下清远气温变化特征   总被引:3,自引:1,他引:2       下载免费PDF全文
根据1957—2007年清远站的年和月平均气温资料,采用线性倾向的最小二乘法估计分析季及年平均气温的变化趋势。结果表明:在气候变暖背景下,近50 a清远年平均气温存在与全球、中国及广东省同步的增暖趋势,增暖幅度(平均气温线性增暖速率为0.17℃/10 a)高于近50 a全球平均线性增暖速率,低于近50 a中国及广东省平均线性增暖速率。四季及年平均气温在变暖趋势上基本同步,只有冬季稍落后。且在气候变暖背景下,清远异常冷、暖冬事件出现频繁,暖冬明显。应用Mann-Kendall法检测气候的突变性,表明清远冬季平均气温于1968年前后存在由低向高的突变。  相似文献   

7.
西南地区不同地形台阶气温时空变化特征   总被引:2,自引:0,他引:2       下载免费PDF全文
利用西南地区135个站1961—2005年的年、月气温资料,按海拔高差及地形气候特征划分成不同的三级地形台阶及4个分区,分析了不同分区的气温时空变化特征。结果表明:西南地区大部年平均气温表现出明显的增温趋势,上升趋势最显著的地区在西藏高原等高海拔地区,而在四川的东北部及云南北部存在降温中心。各分区四季的增温速率排序与全国平均情况有所不同,依次为冬季、秋季、夏季或春季,且均表现出冬季增温趋势明显大于其他季节的特性。各分区年平均气温20世纪60年代至80年代中期基本表现为明显的下降趋势或无明显的增减趋势,但自1997年以来,均表现出显著的增温趋势。突变检测的结果也表明,各分区年平均气温突变的区域或突变点大部分发生在90年代后期以后,且高海拔地区增温突变启动时间早于其他低海拔地区。  相似文献   

8.
豫东北主要农作物对气候变暖的响应   总被引:3,自引:0,他引:3  
利用豫东北具有代表性的濮阳、南乐两个国家基本站1971-2000年的气象和农气观测资料,分析了气候变化趋势及其对农作物的影响,结果表明:濮阳和南乐30 a年平均气温呈逐年升高趋势,1993年后升高趋势明显。气候变暖使冬小麦播种期推延,返青提前,对冬小麦增产有利,也利于玉米生育期的延长和产量提高;终霜期明显提前,初霜期略推迟,霜期变短,使棉花平均生育期延长,霜后花率降低,对产量和质量提高有利。  相似文献   

9.
根据青海省玉树站近58 a (1951~2008年)的逐月气温资料,利用线性回归、小波分析、M ann-Kendall法和S/R分析等方法,分析了该站春、夏、秋、冬季及年平均气温的变化特征,结果表明:1)近58 a来玉树站各季节和年平均气温均经历了先降后升的阶段,整体呈现出上升趋势,其中春季气温上升最快的阶段出现在20世纪80到90年代,其它季节和年平均气温出现在20世纪末到21世纪初;2)各季及年平均气温普遍具有准5 a的年际振荡;3)各季和年平均气温突变普遍发生在上世纪90年代;4)根据S/R分析得出,未来一段时期玉树站气温依旧保持增暖趋势,尤其在秋、冬季的增温显著。   相似文献   

10.
Summary The present study is an analysis of the observed extreme temperature and precipitation trends over Yangtze from 1960 to 2002 on the basis of the daily data from 108 meteorological stations. The intention is to identify whether or not the frequency or intensity of extreme events has increased with climate warming over Yangtze River basin in the last 40 years. Both the Mann-Kendall (MK) trend test and simple linear regression were utilized to detect monotonic trends in annual and seasonal extremes. Trend tests reveal that the annual and seasonal mean maximum and minimum temperature trend is characterized by a positive trend and that the strongest trend is found in the winter mean minimum in the Yangtze. However, the observed significant trend on the upper Yangtze reaches is less than that found on the middle and lower Yangtze reaches and for the mean maximum is much less than that of the mean minimum. From the basin-wide point of view, significant increasing trends are observed in 1-day extreme temperature in summer and winter minimum, but there is no significant trend for 1-day maximum temperature. Moreover, the number of cold days ≤0 °C and ≤10 °C shows significant decrease, while the number of hot days (daily value ≥35 °C) shows only a minor decrease. The upward trends found in the winter minimum temperature in both the mean and the extreme value provide evidence of the warming-up of winter and of the weakening of temperature extremes in the Yangtze in last few decades. The monsoon climate implies that precipitation amount peaks in summer as does the occurrence of heavy rainfall events. While the trend test has revealed a significant trend in summer rainfall, no statistically significant change was observed in heavy rain intensity. The 1-day, 3-day and 7-day extremes show only a minor increase from a basin-wide point of view. However, a significant positive trend was found for the number of rainstorm days (daily rainfall ≥50 mm). The increase of rainstorm frequency, rather than intensity, on the middle and lower reaches contributes most to the positive trend in summer precipitation in the Yangtze.  相似文献   

11.
Summary Trends in the time series of air temperature, precipitation, snow cover duration and onset of climatic seasons at ten stations in Estonia during 1951–2000 are analysed. Using the conditional Mann-Kendall test, these trends are compared with trends in the characteristics of large-scale atmospheric circulation: the NAO and AO indices, frequency of circulation forms according to the Vangengeim-Girs’ classification, and the northern hemisphere teleconnection indices. The objective of the study is to estimate the influence of trends in circulation on climate changes in Estonia. Statistically significant increasing trends in air temperature are detected in January, February, March, April and May, in winter (DJF), spring (MAM) and in the cold period (NDJFM). The trends in precipitation, as a rule, differ from station to station. Increasing trends are present during the cold half-year – from October until March – and also in June. Snow cover duration has decreased in Estonia by 17–20 days inland and by 21–36 days on the coast. The onsets of early spring and spring have shifted to an earlier date. Some important changes have occurred in the parameters of atmospheric circulation during 1951–2000. Intensity of zonal circulation, i.e. westerlies, has increased during the cold period, especially in February and March. Results of the conditional Mann-Kendall test indicate that the intensification of westerlies in winter is significantly related to climate changes in winter and also in spring. A negative trend in the East Atlantic Jet (EJ) index, i.e. the weakening of the westerlies in May has caused warming during that month. Decrease in northerly circulation, i.e. in frequency of circulation form C and in East Atlantic/West Russia teleconnection index (EW) is related to an increase in precipitation in October.  相似文献   

12.
1951—2010年大连市气温变化特征   总被引:1,自引:0,他引:1  
利用1951—2010年大连市气温资料,采用气候趋势系数和气候倾向率、Mann-Kendal1突变分析等方法对年和季平均气温、最高最低气温变化特征进行了分析和突变检验。结果表明:大连市年和季平均气温呈上升趋势,进入21世纪,升温趋势有所减缓;大连市年平均气温的增温速率为0.33/10 a,明显高于近50 a中国平均增温速率0.22/10 a,更高于近50 a全球平均0.13/10 a的增温速率。大连市平均气温的升高主要发生在春季和冬季;年平均最低气温的升温幅度大于年平均最高气温的升温幅度;年、季平均气温存在突变,突变始于1987—1990年前后,突变前后平均气温均值相差较大;年、季平均最高气温和最低气温大都存在突变,但秋季平均最高气温无突变。  相似文献   

13.
利用1951—2010年大连市气温资料,采用气候趋势系数和气候倾向率、Mann-Kendal1突变分析等方法对年和季平均气温、最高最低气温变化特征进行了分析和突变检验。结果表明:大连市年和季平均气温呈上升趋势,进入21世纪,升温趋势有所减缓;大连市年平均气温的增温速率为0.33/10 a,明显高于近50 a中国平均增温...  相似文献   

14.
宁夏近百年来的气候变化及突变分析   总被引:68,自引:19,他引:68  
李艳春  李艳芳 《高原气象》2001,20(1):100-104
以宁夏北部地区近百年来的降水量、气温距平资料以及全区各季有仪器观测以来的温度降水资料为基础,利用Mann-Kendall突变检验法和滑动t检验法,分析了宁夏近百年来气候变化的阶段性和突变特点。结果表明:近百年来宁夏气候大概经历了五个主要阶段;80年代中期年平均气温及秋冬季平均气温发生改变;60年代左右年降水量发生突变;70年代中后期全区秋季降水量出现突变。  相似文献   

15.
The trends and features of China’s climatic change in the past and future are analysed by applying station obser-vations and GCM simulation results. Nationally, the country has warmed by 0.3oC in annual mean air temperature and decreased by 5% in annual precipitation over 1951-1990. Regionally, temperature change has varied from a cooling of 0.3oC in Southwest China to a warming of 1.0oC in Northeast China. With the exception of South China, all regions of China have shown a declination in precipitation. Climatic change has the features of increasing remark-ably in winter temperature and decreasing obviously in summer precipitation. Under doubled CO2 concentration, climatic change in China will tend to be warmer and moister, with increases of 4.5oC in annual mean air temperature and 11% in annual precipitation on the national scale. Future climatic change will reduce the temporal and spatial differences of climatic factors.  相似文献   

16.
ABSTRACT

Trends in indices based on daily temperature and precipitation are examined for two periods: 1948–2016 for all stations in Canada and 1900–2016 for stations in the south of Canada. These indices, a number of which reflect extreme events, are considered to be impact relevant. The results show changes consistent with warming, with larger trends associated with cold temperatures. The number of summer days (when daily maximum temperature >25°C) has increased at most locations south of 65°N, and the number of hot days (daily maximum temperature >30°C) and hot nights (daily minimum temperature >22°C) have increased at a few stations in the most southerly regions. Very warm temperatures in both summer and winter (represented by the 95th percentile of their daily maximum and minimum temperatures, respectively) have increased across the country, with stronger trends in winter. Warming is more pronounced for cold temperatures. The frost-free season has become longer with fewer frost days, consecutive frost days, and ice days. Very cold temperatures in both winter and summer (represented by the 5th percentile of their daily maximum and minimum temperatures, respectively) have increased substantially across the country, again with stronger trends in the winter. Changes in other temperature indices are consistent with warming. The growing season is now longer, and the number of growing degree-days has increased. The number of heating degree-days has decreased across the country, while the number of cooling degree-days has increased at many stations south of 55°N. The frequency of annual and spring freeze–thaw days shows an increase in the interior provinces and a decrease in the remainder of the country. Changes in precipitation indices are less spatially coherent. An increase in the number of days with rainfall and heavy rainfall is found at several locations in the south. A decrease in the number of days with snowfall and heavy snowfall is observed in the western provinces, while an increase is found in the north. There is no evidence of significant changes in the annual highest 1-day rainfall and 1-day snowfall. The maximum number of consecutive dry days has decreased, mainly in the south.  相似文献   

17.
中国冬半年最低气温概率分布特征   总被引:4,自引:0,他引:4  
 根据1955-2005年中国160个站冬半年 (当年11月至翌年4月)平均最低气温资料,使用统计检验的方法,分析了近50 a中国冬半年最低气温的突变事实,在此基础上给出了气候变暖前后最低气温的概率分布,比较了变暖前后时段全国最低气温空间分布的差异。结果表明:1) 20世纪80年代末中国冬半年最低气温发生了显著突变,进入异常增暖时期,其增温程度比平均气温明显;2) 增暖后中国最低气温的概率分布发生了明显的变化,最低气温偏冷的概率显著减小,偏暖的概率明显增大;3)气候变暖后除西南地区最低气温上升幅度不显著外,其余地区均呈现显著增温趋势。  相似文献   

18.
中国冬半年最低气温概率分布特征   总被引:3,自引:0,他引:3  
根据1955-2005年中国160个站冬半年 (当年11月至翌年4月)平均最低气温资料,使用统计检验的方法,分析了近50 a中国冬半年最低气温的突变事实,在此基础上给出了气候变暖前后最低气温的概率分布,比较了变暖前后时段全国最低气温空间分布的差异。结果表明:1) 20世纪80年代末中国冬半年最低气温发生了显著突变,进入异常增暖时期,其增温程度比平均气温明显;2) 增暖后中国最低气温的概率分布发生了明显的变化,最低气温偏冷的概率显著减小,偏暖的概率明显增大;3)气候变暖后除西南地区最低气温上升幅度不显著外,其余地区均呈现显著增温趋势。  相似文献   

19.
Summary  Changes in surface air temperature during the last century are widely discussed among researchers in the field of climatic change. Using various techniques, we investigate trends and periodicity of surface air temperature series from eight meteorological stations in the Eastern Mediterranean. For the analysis, we use the Mann-Kendall rank test, low-pass filtering, autocorrelation spectral analysis and maximum entropy spectral analysis. The latter two tests are compared. The study is based on series over one hundred years in length for four stations, and over fifty years in length for the other four. Increasing and decreasing surface temperature trends were found. These trends, however, are only significant for Malta, Jerusalem, and Tripoli at the 99% confidence level (positive trend) and for Amman at the 95% confidence level (negative trend). We also found inter-decadal variations in surface air temperature, including a fairly regular quasi 20-year oscillation, although its amplitude varied between different cycles. A period of warming began around 1910 at all stations. During the 1970s, the annual mean temperature series exhibit warming, but this warming was not uniform, continuous or of the same order at all the stations. The results of the Autocorrelation Spectral Analysis and the Maximum Entropy Spectral Analysis are similar, pointing to the reliability of the results. The quasi-biennial oscillation (QBO) exists at all stations during both increasing and decreasing trends. Similarly, a broad maximum from 3–8 years (related to El Ni?o) is found at Malta, Athens, Jerusalem, Beirut, and Latakia. An inverse relationship between El Ni?o and the North Atlantic Oscillation with surface air temperature over the Eastern Mediterranean is found at a highly significant confidence level. Received November 15, 1999 Revised August 29, 2000  相似文献   

20.
Temporal trends between 1951 and 2007 in annual Indian Summer Monsoon (ISM) precipitation, frequency of severe drought years and onset date of ISM were analysed on a 0.25°?×?0.25° grid cell basis across India using APHRODITE daily gridded precipitation data. Locations which experienced temporal trends of increasing or decreasing inter-annual variation in annual ISM precipitation and onset date of ISM were detected using the non-parametric Mann-Kendall test. A new method of defining local onset of ISM from daily precipitation data was developed to enable countrywide temporal trend analysis of onset date. India was characterised by a heterogeneous spatial distribution in the magnitude of inter-annual variation and location of significant temporal trends in the examined facets of ISM precipitation. A greater extent of the country experienced significant trends (p?<?0.05) of increasing inter-annual variation rather than simple increasing or decreasing trends in annual ISM precipitation and onset date of ISM. Field significance tests showed grid cells reporting significant trends were significant (p?<?0.05) at the global or field level (except trends of increasing, i.e. later, ISM onset date). This research provides finer spatial detail regarding trends and variation in annual ISM precipitation, severe drought years and onset date of ISM complementing recent studies on trends in extreme precipitation events over India to produce a comprehensive overview of recent behaviour of ISM precipitation. These findings will benefit water managers charged with managing water resources sustainably at a fine spatial scale (the watershed or basin level).  相似文献   

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