首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 406 毫秒
1.
1996年以来,黑龙江省草地螟第三暴发周期持续至今,危害日益加重。以1959—2008年黑龙江省28个国家基本站气象资料以及草地螟暴发期等资料为基础,分析了黑龙江省草地第三暴发周期的气候特征及风险概率。结果表明:近50 a来,黑龙江省年平均气温、年平均最低气温呈显著的上升趋势,通过0.001显著性检验,气温在1988年前后出现突变。其他要素如降水量、降水日数、风速和日照时数均呈减少趋势,但只有年日照时数和年平均风速的减少趋势通过了显著性检验。哈尔滨草地螟始发日期与同期平均气温、日最高气温、最低气温、最小相对湿度关系密切,本地越冬虫源春季羽化对气温、相对湿度敏感性较高;同时,始见日期与最大风速的风向相关较为密切,可能是由于外地虫源对风向敏感性较高。通过对黑龙江省草地螟高峰期首日的风险概率分析,得出草地螟高峰期出现在5月最后一个候的风险概率为23.6%;出现在6月上旬的风险概率为36.6%;出现在6月中旬的风险概率为24.0%;出现在6月下旬的风险概率为14.4%。  相似文献   

2.
The present study tends to describe the survey of climatic changes in the case of the eastern and central areas of Iran and, to some extent, the northern parts. The monthly and yearly change trends in the minimum, maximum and mean temperatures, relative humidity, and the precipitation were surveyed for 26 synoptic stations in Iran during a 55-year period. The study was carried out by using the ??-Kendall test. The results showed the same temperature changes for the centrally located stations as the eastern and northern ones. Most of the stations in Zagros showed no significant temperature changes. A significant decrease in the precipitation was seen in summer in different stations. Most of the eastern and centrally located stations showed a decrease in relative humidity trend, while this condition was not recorded in Zagros and northern part of Iran. The present results also showed that the upward trend of minimum air temperature had an effect in increasing the mean air temperature in the stations with temperature ascending trend. This effect of minimum temperature was significantly more than that of the maximum temperature, which could be the result of increasing the amount of greenhouse gases and the reflection of received thermal energies, from land through the night. This increase in the temperature and a decrease in relative humidity would cause an increase in the evaporation of the received precipitation.  相似文献   

3.
华南地区城市化对区域气候变化的影响   总被引:5,自引:2,他引:3  
按照人口数将华南地区站点分为大城市站、一般城市站、郊区站,并利用华南地区1960~2011年的站点观测资料分别计算了3类站点年平均、季节平均的气温、高温日数、降水、相对湿度、风速、日照时数距平序列的变化,分析了城市化对华南地区区域气候的影响。结果表明:相较于背景场,大城市的平均气温有更明显的上升趋势;高温日数在3类站点中均有增加的趋势,在城市化的影响下,大城市的高温日数有明显的增加;平均气温日较差在整个华南地区均有下降趋势,特别是在大城市中。在3类站点中,降雨总量均有减少的趋势,且降雨更多的以中雨及以上的形式表现。该地区的相对湿度、风速、日照时数均呈现减少趋势,在城市化影响下,大城市的相对湿度、风速、日照时数均有明显的减少。华南地区处于我国最大的城市群之一——珠江三角洲地区,同时处于气候系统复杂的热带季风区,因此有必要研究城市化对该地区多个气象变量的可能影响。  相似文献   

4.
1961-2009年东北地区日照时数变化特征   总被引:6,自引:0,他引:6       下载免费PDF全文
根据1961-2009年东北地区104个气象站的日照时数、气温、降水、风速和相对湿度资料,利用趋势分析、Mann-Kendall分析和相关分析等方法,研究东北地区日照时数月、季、年的时空变化特征,同时还对可能影响日照时数的气候因子进行分析。结果表明:东北地区5月日照时数最高,12月日照时数最低。年日照时数呈显著减少趋势,平均每10 a减少40.5 h;除秋季日照时数变化不显著外,其他季节日照时数均显著减少。在20世纪80年代初期存在明显的突变,日照时数开始减少。东北地区日照时数大致呈西高东低的经向分布;除黑龙江北部地区外,其余大部地区日照时数均呈减少的趋势,其中吉林北部地区减少最为明显。东北地区日照时数与气温呈负相关关系,相关系数为-0.40;与降水呈负相关关系,相关系数为-0.37;与风速呈正相关关系,相关系数为0.53;与相对湿度呈负相关关系,相关系数为-0.32。前三者均通过了99.9 %的信度检验,相对湿度通过了99.5 %的信度检验。  相似文献   

5.
The major objective of this study was to investigate the effects of climate change on evapotranspiration from paddy fields. A sensitivity analysis of meteorological variables at the Kao-Hsiung station, one of meteorological stations in southern Taiwan, was carried out using the modified Penman formula. Forty-eight-year records of temperature, relative humidity, sunshine duration, wind speed, and precipitation depth comprised the database. Trend and persistence analyses of the data were performed using the Mann–Kendall test, the Cumulative Deviation test, Linear Regression, andthe Autocorrelation Coefficient. The results indicated that only temperature and relative humidity have significant long-term trends and persistence. Two climatic scenarios, viz. (1) linear extrapolation of climatic trends and (2) the predictions of General Circulation Models (GCMs), were assumed to investigate the effects of climate change on evapotranspiration. The study revealed that evapotranspiration from paddy fields increased under both climatic scenarios studied.  相似文献   

6.
武鹏飞  张钧泳  谭娇 《气象科技》2019,47(3):450-459
采用新疆天山地区55个气象站1961—2015年逐月气象数据,用Mann Kendall突变检验、基于ArcGIS的混合插值及偏相关分析对天山日照时数年、季节特征及影响因素进行分析。结果表明:①天山日照时数年及季节均呈减少趋势,天山各区域变化差异显著,山区及天山北坡变化趋势明显于南坡。②天山北坡、天山南坡及天山山区年日照时数突变时间为1985年、1980年和1988年,云量和降水是导致突变发生的主导因素。③新疆天山年日照时数由西向东逐渐增加,平原多、山区少,春季呈“东北部多、西南部少”,夏季为 “东北部多、西南部少”,平原盆地高于山区,秋季呈现“北少南多,东多西少”,冬季由南向北逐渐减少。④云量、降水是导致天山地区日照减少的主要因素,少云区日照时数较多,多云区日照时数较少,天山云量减幅或增幅区域,日照时数突变量变化明显。  相似文献   

7.
STUDIES ON CLIMATE CHANGE IN CHINA IN RECENT 45 YEARS   总被引:6,自引:0,他引:6       下载免费PDF全文
Based on the data of monthly mean air temperature and precipitation from about 400 stationsin 1951—1995.and the data of maximum and minimum air temperatures,relative humidity,totalcloud cover and low-cloud cover,sunshine duration,evaporation,wind speed,snow-covered daysand depth,and soil temperatures in 8 layers from 0 m down to 3.2 m from 200 odd stations in 1961—1995.the climate change and its characteristics in China in recent 45 years have been analyzedand studied comprehensively.This paper,as the first part of the work.has analyzed the climatechange and regularities of such meteorological elements as mean air temperature,maximum andminimum air temperatures,precipitation,relative humidity and sunshine duration.The possiblemechanism on climate change in China and the climate change and regularities of othermeteorological elements will be discussed in another paper as the second part.  相似文献   

8.
基于陕西1961—2018年94个气象台站逐日气温资料,选取世界气象组织(WMO)提出的10种极端气温指数,分陕北、关中和陕南三个气候区,采用线性趋势分析、Mann-Kendall突变分析和Morlet小波分析,分析了陕西极端气温事件的时空变化特征。结果表明:陕西各极端气温指数在近60 a发生了显著变化,热指数的增加趋势较冷指数的减少趋势更为明显且年际间波动较大,夜指数的变化较相应的日指数变化更为突出,其中暖夜天数的增幅达到了7.4 d/10 a。除极端最低气温外,其余冷指数在1995年前后出现突变,而暖夜和暖昼天数突变发生在2005年以后。冰日、冷昼和热夜天数变化趋势呈现出明显的纬向特征,关中的极端最低气温、冷夜天数、暖夜天数、霜冻天数和夏日天数变化趋势较其他两个区域更为显著。极端指数的周期性变化主要集中在2—8 a。相较于极值指数,相对指数和绝对指数的变化均能较好的反映陕西年平均最高和最低气温的变化趋势。  相似文献   

9.
利用1961—2022年江西74个气象站平均气温、最高气温、最低气温、降水量、相对湿度、平均风速和日照时数资料,对比分析了1991—2020年和1981—2010年新、旧气候态下气象要素差异,探讨气候平均值改变对气候影响评价和预测业务的影响。结果表明:新气候态下,江西省三类气温的年和季节平均值均上升,年降水量总体增加将弱化气温偏高、降水偏多的变化特征。年和季节平均风速距平山区减小而平原地区增大;年日照时数距平总体增加。极端高温年份减少,极端低温年份增多,其中平均气温和最低气温的极端高(低)温年发生概率的降幅(增幅)比最高气温更大。极端强降水年发生概率在赣西北、赣中大部、赣南西北部等地区夏季减少,赣南中南部地区冬季增大。全省历年极端日高温、低温和强降水事件发生站次总体减少。新、旧气候态的更替会对气候业务产生影响,如冬季气温偏冷的年份增加,偏暖的年份减少,需对冷、暖冬事件进行重新评估,夏季降水增多的变化特征减弱,将导致夏季降水预测量级和趋势发生改变。  相似文献   

10.

Spatial and temporal variations in summer and winter extreme temperature indices are studied by using daily maximum and minimum temperatures data from 227 surface meteorological stations well distributed over India for the period 1969–2012. For this purpose, time series for six extreme temperature indices namely, hot days (HD), very hot days (VHD), extremely hot days (EHD), cold nights (CN), very cold nights (VCN), and extremely cold nights (ECN) are calculated for all the stations. In addition, time series for mean extreme temperature indices of summer and winter seasons are also analyzed. Study reveals high variability in spatial distribution of threshold temperatures of extreme temperature indices over the country. In general, increasing trends are observed in summer hot days indices and decreasing trends in winter cold night indices over most parts of the country. The results obtained in this study indicate warming in summer maximum and winter minimum temperatures over India. Averaged over India, trends in summer hot days indices HD, VHD, and EHD are significantly increasing (+1.0, +0.64, and +0.32 days/decade, respectively) and winter cold night indices CN, VCN, and ECN are significantly decreasing (−0.93, −0.47, and −0.15 days/decade, respectively). Also, it is observed that the impact of extreme temperature is higher along the west coast for summer and east coast for winter.

  相似文献   

11.
Based on 1971-2005 monthly mean maximum/minimum temperature,wind speed,relative humidity,sunshine duration,and precipitation data at 25 stations over the Tibetan Plateau,a study of the largest potential evapotranspiration(LPE)is performed by using the Penman-Monteith model.The surface wettability index(SWI)is calculated and examined,together with its space distribution,interannual and seasonal variations,as well as associated causes.The results suggest that the annual area rainfall exhibits a pronounced increasing trend at 15.0 mm per decade; the annual LPE shows a different-degree decrease at-4.6-71.6 mm/10 yr.In the southwestern Ngari prefecture and Nyalam county,the annual SWI displays insignificant decline trends compared to increasing trends in other areas of Tibet(0.02-0.09 per decade).For Tibet,on average,the SWI experiences a noticeable rise at 0.04/10 yr,particularly in 1981-2005.On a seasonal basis,the SWI shows increasing trends,especially in summer.In the 1970s-1980s,the interannual variation is characterized mainly by lower temperature and lower humidity.From the 1990s,air temperature keeps on rising,leading to an appreciable increase in SWI,displayed as a type of warm and humid climate.The salient increases(decrease)of precipitation and relative humidity(mean temperature daily range)are the principal causes of the greatly enhanced SWI in the region.The pronounced decrease in mean wind and sunshine duration also plays an active role.  相似文献   

12.
1996年以来黑龙江省草地螟第三暴发周期持续至今,危害日益加重。以1959-2008年黑龙江省28个国家基本站的气象资料以及草地螟暴发期等资料为基础,分析了黑龙江省草地第三暴发周期的气候特征及风险概率。结果表明:近50 a来,黑龙江省年平均气温、年平均最低气温呈显著的上升趋势,通过0.001显著性检验,气温在1988年前后出现突变。其它要素,如降水量、降水日数、风速、日照时数均呈减少趋势,但只有年日照时数和年平均风速的减少趋势通过了显著性检验。哈尔滨草地螟始发日期与同期平均气温、日最高气温、最低气温、最小相对湿度关系密切,应该是本地越冬虫源春季羽化对气温、相对湿度敏感性较高;同时始见日期与最大风速的风向相关较为密切,可能是由于外地虫源对风向敏感性较高。通过对黑龙江省草地螟高峰期首日的风险概率分析,得到黑龙江省草地螟高峰期出现在5月最后一个候的风险概率为23.6%;出现在6月上旬的风险概率为36.6%;出现在6月中旬的风险概率为24%;出现在6月下旬的风险概率为14.4%。  相似文献   

13.
为深入了解气象探测环境对气温观测数据的影响,利用2017年北京市观象台(54511)与南海子站(A1274)逐小时地面气象要素数据,分析两站气温差异以及因站点探测环境导致的日照、风速和降水对两站气温差异的影响。结果表明:2017年两站气温差异较明显,年平均气温54511站比A1274站高0.75℃;两站逐月平均气温54511站全年高于A1274站,两站差值7月最低为0.60℃,9月最高为1.09℃;两站平均日最高气温较接近,平均日最低气温差异较大,54511站较A1274站高1.24℃;两站气温的日变化特征相似,呈单峰分布,54511站气温日较差低于A1274站。两站小时气温差值随着日照时长和强度的增加而增加,短波辐射效应最强的10-14时和长波辐射效应最强的19-23时两站气温差值与当日白天直接辐射曝辐量的相关系数分别为0.459和0.601;水平风速对两站气温差值的影响较大。水平风速超过5 m·s-1时,两站气温差小于0.1℃;当水平风速不超过1 m·s-1时,两站观测气温差值达到1.28℃;降水天气下两站的气温差值小于非降水天气,出现降水时次54511站平均气温仅比A1274站高0.2℃。两站相距4.3 km,气候均一,测站周边2 km范围内建设用地占比54511站比A1274站高约30%,植被占比低28%,水体占比相差不大。另外,54511站附近的五环路具有低反射率和高热容的特征,白天能够吸收太阳辐射储存较多的热量,这些热量在夜间释放,可能是两站探测环境对太阳辐射吸收的差异决定了两站温差受太阳辐射和风速的影响较大,而受降水影响较小。  相似文献   

14.
近40 a来青海湖地区的气候变化分析   总被引:25,自引:2,他引:25  
选用青海湖流域天峻、刚察、共和、茶卡4站41a(1958—1998年)的气象资料,用主成分分析、趋势分析和相关分析对各气象要素的年、季平均值序列进行了分析。结果表明:青海湖地区降水和日照时数的年际变化较大,但无明显的长期趋势;该地区的平均气温、平均最高、平均最低气温都明显升高,其中以平均最低气温上升最为明显;风速呈明显的下降趋势,20世纪70年代最大,80年代最小,90年代又略有增加;该区80年代相对湿度较大,而90年代向暖干发展。  相似文献   

15.
《大气与海洋》2013,51(2):243-256
Abstract

Trends and variations in daily temperature and precipitation indices in southern Québec are examined for the period 1960–2005. The indices are based on daily temperature and daily precipitation which have been recently adjusted at 53 climatological stations. The adjustments were made for site relocation, changes in observing programs, known instrument changes and measurement program deficiencies. The results show that the surface air temperature has increased in southern Québec over 1960–2005. Significant warming is evident in the western, southern and central parts of the province but the increasing trends become smaller toward the east. The warming is greater during the winter although many significant increasing trends are found in the summer. The analysis of the temperature extremes strongly indicates the occurrence of more nights with extreme high temperatures in all seasons. The temperature indices also suggest an increase in the number of thaw/frost days during the winter (days with maximum temperature above 0°C and minimum temperature below 0°C), a decrease in the length of the frost season, an increase in the length of the growing season, a decrease in heating degree days and an increase in cooling degree days. The precipitation indices show an increase in the annual total rainfall although many stations indicate decreasing trends during the summer. The number of days with rain has increased over the region whereas the number of days with snow and the total snow amounts have decreased over the past 46 years.  相似文献   

16.
近40年黄河源区气候要素分布特征及变化趋势分析   总被引:12,自引:7,他引:12  
徐宗学  和宛琳 《高原气象》2006,25(5):906-913
用Mann-Kendall统计检验方法对黄河源区13个气象站点1959—1997年日照、气温、降水、蒸发的分布特征和变化趋势进行了分析,结果表明:近40年黄河源区年平均日照时数表现为微弱的下降趋势,空间分布呈明显的从北部向南部减少的态势,变化趋势从中部向西部、东部、北部逐渐减少;年平均气温呈明显的上升趋势,空间分布规律从西向东、从南向北逐渐增加,变化趋势为中部、南部地区上升趋势最小,北部、东部、西部上升幅度较大;多年平均降水呈较弱的下降趋势,空间分布规律从东南向西北逐渐减少,变化趋势表现为大部分地区降水量呈下降趋势;年平均蒸发量的下降趋势幅度较大,空间分布规律从北部向南部逐渐减少,变化趋势表现为大部分地区呈减少趋势,以北部地区最为明显。另外,本文也应用线性倾向估计方法对黄河源区各气候要素进行了分析,这两种方法得到的结果基本一致。  相似文献   

17.
利用阿勒泰地区7个气象观测站1981-2013年积雪初、终日期、积雪期(积雪初、终日期间日数),以及同期平均气温、平均0厘米地面温度、降水量、日照时数和平均风速资料,分析了该区积雪的变化特征及其与五个气象因子的关系。结果表明:阿勒泰地区平均初日为11月3日,终日为4月2日,平均积雪期为152d;近33年阿勒泰地区积雪初日呈上升的趋势,而终日和积雪期是呈下降趋势;除了吉木乃站的积雪初日气候倾向率是负值外,其余各站均是正值的,积雪终日的气候倾向率各站均为负值,积雪期的气候倾向率除了吉木乃站外其余均是正值;各站在积雪期内与降水量呈显著的正相关,表明降水量越多积雪持续时间越长,而且七个站均通过了显著性检验,降水因子在五个因子的对各站积雪期的影响较大;阿勒泰地区的各站积雪期与积雪初、终日期间的风速、降水量、0厘米地温、日平均气温、日照时数五个因子的相关系数中有57%的通过信度0.05的显著性检验,还有20%的通过了信度0.001的显著性检验;  相似文献   

18.
Assessment of climate extremes in the Eastern Mediterranean   总被引:4,自引:0,他引:4  
Summary Several seasonal and annual climate extreme indices have been calculated and their trends (over 1958 to 2000) analysed to identify possible changes in temperature- and precipitation-related climate extremes over the eastern Mediterranean region. The most significant temperature trends were revealed for summer, where both minimum and maximum temperature extremes show statistically significant warming trends. Increasing trends were also identified for an index of heatwave duration. Negative trends were found for the frequency of cold nights in winter and especially in summer. Precipitation indices highlighted more regional contrasts. The western part of the study region, which comprises the central Mediterranean and is represented by Italian stations, shows significant positive trends towards intense rainfall events and greater amounts of precipitation. In contrast, the eastern half showed negative trends in all precipitation indices indicating drier conditions in recent times. Significant positive trends were revealed for the index of maximum number of consecutive dry days, especially for stations in southern regions, particularly on the islands.Current affiliation: National Observatory of Athens, Athens, Greece.  相似文献   

19.
1951-2005年内蒙古东部气候变化特征分析   总被引:4,自引:1,他引:3       下载免费PDF全文
选取1951-2005年内蒙古东部4盟市48个地面气象观测站的地面气象观测资料,采用趋势分析法分析了内蒙古东部地区气温、降水、风速和日照时数的变化趋势及空间分布特征。结果表明:近50 a来内蒙古东部地区气温升高,且极端最低温度升高的程度大于极端最高气温升高的程度;呼伦贝尔东部和赤峰西南部降水增加较明显,通辽降水减少最明显;平均风速变小,仅通辽呈风速增大的趋势;日照时数和降水量的变化趋势相反。  相似文献   

20.
采用NCEP/NCAR逐月再分析资料、广西北部43个气象台站的温度、湿度、风、降水、导线覆冰等观测资料以及广西输电线路覆冰资料,建立雨凇覆冰厚度计算模型,并得出气象台站的历史覆冰厚度序列。采用数理统计和合成分析等方法研究典型覆冰年份的时空特征、环流背景及气象要素变化特征,结果发现:广西输电线路覆冰主要出现在冬季的桂北,并有逐年减轻的趋势,MannKendall突变检验表明,存在1个明显的突变点,出现在1985年;广西典型覆冰年份,500 hPa欧亚大陆中高纬地区呈明显的"两槽一脊"型,广西高空处于南支槽前,地面受冷高压脊控制;赤道中东太平洋,从夏季到秋季,海温由偏高转为偏低,到冬季SSTA维持为负距平,说明广西输电线路覆冰与LA NINA事件有较密切的关系。当日最低气温在0.2℃以下,风速5 m·s-1,并伴有雨凇和弱降水,低温寡照天气时容易出现覆冰。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号