共查询到20条相似文献，搜索用时 250 毫秒
1.
基于1960--2005年汉阴县的气温及降水资料,采用线性拟合和谐波分析方法,分析汉阴县近46a的气候变化。结果表明：近46a汉阴县年平均气温总体呈上升趋势,温度年代际振荡冷暖交替明显,温度年际变化的主要贡献为年循环分量;降水的波动性较大,降水偏少、偏多年代和温度呈反位相,温度和降水存在准10a振荡周期;46a内有明显的气候跃变,20世纪80年代跃变尤其显著,气温的跃变比降水振幅更大,其趋势与我国西北地区近50a气候变化基本一致。此外,谐波分析显示降水的年循环分量较温度明显偏弱,降水的随机波动对年际降水影响更强。 相似文献
2.
中国气候变化的检测及预估 总被引：44，自引：4，他引：44
对近5a来中国科学家在气候变化的检测及预估等方面的研究工作及主要成果进行了总结:采用最新的器测时期资料和代用温度资料对中国地区近50a、100a的温度和降水变化规律进行再分析,初步重建了中国过去1000a的地表温度序列;对20世纪中国气候变化进行了检测,分析了中国气候变化的原因;预估了中国21世纪气候变化。结果表明:近百年中国气候变化的主要特征与全球气候变化的趋势一致。中国近百年增暖的幅度为0.5～0.8℃,比全球同期增温略高。近50a中国平均气温升高以北方为主,升温速率达0.8℃/10a,远大于北半球平均的升温速率。中国雨型的年代际变化明显,西北西部从20世纪80年代中降水明显增多,以新疆最为显著。中国东部则由70年代末以前的北涝南旱型转为以后的南涝北旱型。气候变暖后,中国的极端天气和气候事件的发生频率和强度也出现了变化。 相似文献
3.
中国西北东部汛期降水对青藏高原东部春季感热在准3a周期上的响应 总被引：3，自引：0，他引：3
利用1960—2010年中国西北东部地区39个气象站的逐日降水资料和NCEP/NCAR月平均地表感热通量再分析资料以及大气环流各要素场资料,通过多锥度-奇异值分解(MTM-SVD)等方法,分析了中国西北东部汛期降水、青藏高原东部春季感热的周期振荡特征以及它们在准周期循环上的协同耦合关系。结果表明,感热与降水均存在显著的准3 a周期,其耦合场在准3 a周期上表现也最为明显。当青藏高原东部春季感热在青藏高原主体上偏强(弱)时,对应中国西北东部汛期降水的异常偏多(少)。该准3 a周期循环上的协同关系在1960—1982年表现最为显著,1983—1990年为调整阶段,90年代之后又逐渐明显。青藏高原东部春季感热对大气环流的持续加热过程影响西北东部汛期降水,且主要体现在8月。 相似文献
4.
采用1951—2012年GPCP、中国160站台站降水资料及NOAA海表温度资料,分析了中国东部夏季降水及热带印度洋偶极子(IOD)的年际变化特征,以及两者的年代际变化关系。结果表明,中国东部夏季降水主要呈现两种模态分布,即"+-+"三极型和"-+"偶极型。并且在1953—1973年和2002—2012年中国东部夏季降水分别存在准2 a和4 a的震荡周期,年际变化明显。相关性分析发现,夏季IOD时间序列与中国东部夏季降水场的第三模态所对应的时间序列场呈负相关关系,且通过了信度为0.05的显著性检验,说明夏季IOD与中国东部夏季降水第三模态相关性较好。 相似文献
5.
中国东部夏季降水的准两年周期振荡及其成因 总被引：18，自引：13，他引：18
应用中国160测站降水资料和ERA-40再分析资料以及EOF和熵谱分析方法,分析了中国夏季(6～8月)降水和东亚水汽输送通量的年际变化,表明中国(特别是华南、长江流域和淮河流域以及华北等地区)夏季降水具有2～3 a周期变化特征,即准两年周期的振荡特征,并表明中国降水的这种周期振荡与东亚上空夏季风水汽输送通量的准两年周期振荡密切相关;并且,还利用NCEP/NCAR的海表温度和日本气象厅的沿137°E海温剖面观测资料,分析了热带西太平洋表层与次表层海温的年际变化,揭示了热带西太平洋热力状态的变化也有显著的准两年周期的变化特征.作者利用相关和集成分析来讨论热带西太平洋热状态的准两年周期振荡对中国夏季降水和东亚水汽输送的影响,表明了热带西太平洋海温的准两年周期振荡对东亚夏季风及其所驱动的水汽输送都有很大影响.此外,作者还利用东亚/太平洋型(EAP型)遥相关理论,简单地讨论了热带西太平洋热力状态的准两年周期振荡影响中国夏季风降水准两年周期变化的物理机制. 相似文献
6.
采用1958-2007年国家级2419地面台站0.5°×0.5°格点降水场和NCEP/NCAR月平均再分析资料,对中国东部冬季降水量变化及对应的大气环流变化特征进行研究。结果表明：冬季近50 a降水量时间序列表现出明显的长期气候变化趋势。20世纪90年代降水较多,大气水汽充足, 60、70年代相反,这种特征反映出水汽在东亚地区输送的强弱及从海洋输入中国大陆水汽的多寡。降水量强弱年差值合成的异常降水量可达40 mm以上。降水量与水汽收支时间序列的相关系数为0.605。水汽收支与降水场的回归系数揭示了长江流域以南地区为异常大值区。降水量强年,冬季风偏弱,对流层低层和高层为异常气旋式环流,低层盛行异常偏南风,孟加拉湾、南海异常暖湿水汽输送到中国东部地区,中国东部近海海温偏高,配合加强的异常垂直上升运动,有利于水汽的增加,造成降水量增加。 相似文献
7.
华北地区降水多时间尺度演变特征 总被引：3，自引：0，他引：3
华北地区的水资源短缺及相关的生态环境恶化是中国亟待解决的问题之一。降水是水资源最重要的因素,根据华北地区25个测站的长期年降水量资料和15个测站历史旱涝资料,利用Mann-Kendall检验、功率谱和小波变换等方法进行的分析研究表明,华北地区的降水存在明显的准2 a振荡和准19 a周期变化特征,降水在1914和1964年发生了两次突变。历史旱涝等级时间序列有明显的4～5 a ENSO模的振荡、准10 a变化、准20 a变化和50～80 a世纪尺度特征。 相似文献
8.
华北地区降水多时间尺度演变特征 总被引：1，自引：0，他引：1
华北地区的水资源短缺及相关的生态环境恶化是中国亟待解决的问题之一。降水是水资源最重要的因素,根据华北地区25个测站的长期年降水量资料和15个测站历史旱涝资料,利用Mann-Kendall检验、功率谱和小波变换等方法进行的分析研究表明,华北地区的降水存在明显的准2 a振荡和准19 a周期变化特征,降水在1914和1964年发生了两次突变。历史旱涝等级时间序列有明显的4～5 a ENSO模的振荡、准10 a变化、准20 a变化和50～80 a世纪尺度特征。 相似文献
9.
10.
利用博州地区4个气象观测站1958--2006年的月平均气温和月降水量等资料,通过气候变化趋势、突变检验、小波变换等分析了近50a博州地区气候变化特征。表明,博州年平均气温处于增暖趋势,90年代前期出现突变;年降水量也呈增多趋势,90年代后期出现突变;气温与降水都具有准4a左右周期振荡： 相似文献
11.
Temperature and precipitation are two main variables in climate changes.Spatial-temporal resolutions of temperature and precipitation,and recent studies on climate variability in China are summarized and discussed in this review.Recent 100-year datasets are used to reveal quasi-20-year and quasi-70-year oscillations in eastern China,as well as precipitation pattern shift in China.An oscillation with the timescale of 70-80 years is introduced in eastern China.derived from 500-year and 1000-year proxy and observation records.Finally,it is noted that more research achievements on climate change in China depend upon developing or reconstructing long term series,studying in regularity and mechanism,as well as upon prediction and service etc. 相似文献
12.
Temperature and precipitation are two main variables in climate changes. Spatial-temporal resolutions of temperature and precipitation, and recent studies on climate variability in China are summarized and discussed in this review. Recent 100-year datasets are used to reveal quasi-20-year and quasi-70-year oscillations in eastern China, as well as precipitation pattern shift in China. An oscillation with the timescale of 70-80 years is introduced in eastern China, derived from 500-year and 1000-year proxy and observation records. Finally, it is noted that more research achievements on climate change in China depend upon developing or reconstructing long-term series, studying in regularity and mechanism, as well as upon prediction and service etc. 相似文献
13.
近50年来湛江、韶关气候变化的小波分析 总被引：12，自引：27，他引：12
利用MHAT小波函数分析了湛江和韶关两地近50年平均气温和年降水量多时间尺度的演变特征,并对其气候突变进行了初步分析。结果表明,湛江气温变化包含了16年、4年和2年的振荡周期,其降水具有11年、4年的周期变化特征;而韶关的温度序列只具有5年、3年的高频振荡周期,降水变化则包含了11年、7年、4.5年的周期振荡。经气候突变的分析检验,湛江、韶关的气温及降水在不同时间尺度下具有不同的突变点。 相似文献
14.
Interdecadal Variability of East Asian Summer Monsoon Precipitation over 220 Years （1777-1997） 总被引：1，自引：1，他引：0
In this study, long-term (1777–1997) precipitation data for Seoul, Korea, wetness indices from eastern China, and modern observations are used to identify the interdecadal variability in East Asian summer monsoon precipitation over the last 220 years. In the East Asian monsoon region, two long-term timescales of dry–wet transitions for the interdecadal variability and quasi-40-and quasi-60-year timescales are dominant in the 220-year precipitation data of Seoul, as well as in the wetness indices over China.... 相似文献
15.
Climate Change in China from 1880 to 1998 and its Impact on the Environmental Condition 总被引：27，自引：0，他引：27
The global mean surface air temperature (SAT) or the Northern Hemisphere mean SAT has increased since the late nineteenth century, but the mean precipitation around the world has not formed a definite tendency to increase. A lot of studies showed that different climate and environmental changes during the past 100 years over various regions in the world were experienced. The climate change in China over the past 100 years and its impact on China's environmental conditions needs to be investigated in more detail.Data sets of surface air temperature and atmospheric precipitation over China since 1880 up to the present are now available. In this paper, a drought index has been formulated corresponding to both the temperature and precipitation. Based on three series of temperature, precipitation, and drought index, interdecadal changes in all 7 regions of China and temperature differences among individual regions are analyzed. Some interesting facts are revealed using the wavelet transform method. In Northeast China, the aridification trend has become more serious since 1970s. Drought index in North China has also reached a high value during 1990s, which seems similar to that period 1920s–1940s. In NorthwestChina, the highest temperature appeared over the period 1930s–1940s. Along the Yangtze River valley in central eastern China and Southwest China, interdecadal high temperature occurred from 1920s to 1940s and in 1990s, but the drought climate mainly appeared from 1920s to early 1940s. In South China, temperature remained at a high value over the period 1910s–1940s,but the smaller-scale variation of drought index was remarkable from 1880 to 1998. Consequently, the quasi-20-year oscillation (smaller-scale variation) and the quasi-70-year oscillation (secular variation) obviously exist in temperature and precipitation series in different regions over China.Climate change and intensified human activity in China have induced certain environmental evolutions, such as the frequency change of dust-storm event in northern China, no-flow in the lower reaches of the Yellow River and the runoff variation in Northwest China. On the other hand, frequent floods along the Yangtze River and high frequency of drought disaster have resulted in tremendous economic losses in the last decade in China. The primary reason for these happenings may be attributed to the evolution of the monsoon system in East Asian. 相似文献
16.
CLIMATE CHANGE: LONG-TERM TRENDS AND SHORT-TERM
OSCILLATIONS 总被引：2，自引：0，他引：2
Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for
the past 1000 years shows that climate change in the last millennium includes long-term trends and various
oscillations. Two long-term trends and the quasi-70-year oscillation were detected in the global temperature
series for the last 140 years and the NH millennium series. One important feature was emphasized that
temperature decreases slowly but it increases rapidly based on the analysis of different series. Benefits can be
obtained of climate change from understanding various long-term trends and oscillations. Millennial temperature
proxies from the natural climate system and time series of nonlinear model system are used in understanding the
natural climate change and recognizing potential benefits by using the method of wavelet transform analysis. The
results from numerical modeling show that major oscillations contained in numerical solutions on the
interdecadal timescale are consistent with that of natural proxies. It seems that these oscillations in the climate
change are not directly linked with the solar radiation as an external forcing. This investigation may conclude
that the climate variability at the interdecadal timescale strongly depends on the internal nonlinear effects in the climate system. 相似文献
17.
Climatic regime shift and decadal anomalous events in China 总被引：15，自引：0，他引：15
Climatic time series from historical documents and instrumental records from China showed temporal and regional patterns in
the last two to three centuries, including two multidecadal oscillations at quasi-20-year and quasi-70-year timescales revealed
by signal analysis from wavelet transform. Climatic anomalous events on the decadal timescale were identified based on the
two oscillations when their positive (or negative) phases coincide with each other to amplify amplitude. The coldest event
occurred in the decade of 1965–1975 in eastern China, while the periods of 1920–1930, 1940–1950, and 1988–2000 appeared to
be warmer in most parts of China. For the precipitation series in northern China, the dry anomalous event was found in the
late 1920s, while the wet anomalous event occurred in the 1950s. A severe drought in 1927–1929 in northern China coincided
with the anomalous warm and dry decade, caused large-scale famine in nine provinces over northern China. Climatic anomalous
events with a warm-dry or cold-wet association in the physical climate system would potentially cause severe negative impacts
on natural ecosystem in the key vulnerable region over northern China. The spatial pattern of summer rainfall anomalies in
the eastern China monsoon region showed an opposite variations in phase between the Yellow River Valley (North China) and
the mid-low Yangtze River Valley as well as accompanied the shift of the northernmost monsoon boundary. Climatic regime shifts
for different time points in the last 200 years were identified. In North China, transitions from dry to wet periods occurred
around 1800, 1875, and 1940 while the transitions from wet to dry periods appeared around 1840, 1910, and the late 1970s.
The reversal transition in these time points can also be found in the lower Yangtze River. Climatic regime shifts in China
were linked to the interaction of mid- and low latitude atmospheric circulations (the westerly flow and the monsoon flow)
when they cross the Tibetan Plateau in East Asia. 相似文献
18.
Observed,reconstructed, and simulated decadal variability of summer precipitation over eastern China 总被引：2，自引：0，他引：2 
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下载免费PDF全文 Jingyun Zheng Maowei Wu Quansheng Ge Zhixin Hao Xuezhen Zhang 《Acta Meteorologica Sinica》2017,31(1):49-60
Based on observations made during recent decades, reconstructed precipitation for the period A.D. 1736–2000, dry–wet index data for A.D. 500–2000, and a 1000-yr control simulation using the Community Earth System Model with fixed pre-industrial external forcing, the decadal variability of summer precipitation over eastern China is studied. Power spectrum analysis shows that the dominant cycles for the decadal variation of summer precipitation are: 22–24 and quasi-70 yr over the North China Plain; 32–36, 44–48, and quasi-70 yr in the Jiang–Huai area; and 32–36 and 44–48 yr in the Jiang–Nan area. Bandpass decomposition from observation, reconstruction, and simulation reveals that the variability of summer precipitation over the North China Plain, Jiang–Huai area, and Jiang–Nan area, at scales of 20–35, 35–50, and 50–80 yr, is not consistent across the entire millennium. We also find that the warm (cold) phase of the Pacific Decadal Oscillation generally corresponds to dry (wet) conditions over the North China Plain, but wet (dry) conditions in the Jiang–Nan area, from A.D. 1800, when the PDO became strengthened. However, such a correspondence does not exist throughout the entire last millennium. Data–model comparison suggests that these decadal oscillations and their temporal evolution over eastern China, including the decadal shifts in the spatial pattern of the precipitation anomaly observed in the late 1970s, early 1990s, and early 2000s, might result from internal variability of the climate system. 相似文献
19.
近50年新疆气温和降水量变化及其与NAO指数的交叉小波谱分析 总被引：1，自引：0，他引：1
利用1961—2008年的逐日降水和气温资料,采用线性趋势、小波功率谱和交叉小波谱等方法分析了新疆降水和气温的变化,以及与北大西洋涛动(NAO)变化之间的关系。结果表明,近50年新疆存在降水增多和气温上升的趋势,有暖湿化现象,这与西北地区由暖干趋于暖湿的结论相一致。同时,新疆平均年降水量与NAO存在准2年和准6年周期,夏季降水量与NAO存在准3年和准5年周期,冬季降水量与NAO存在准3年周期。新疆年均气温与NAO存在准3年周期,夏季气温与NAO存在准3年周期,冬季气温与NAO存在准3年和准8年周期。新疆全年、冬季和夏季的降水与NAO的周期中,通过显著性检验的高值正相关大多集中在20世纪80年代;而气温与NAO的周期中,通过显著性检验的高值正相关也大多集中在80年代。 相似文献
20.
基于东北区域1961—2019年245站逐日降水资料,利用经验正交函数方法（EOF）、累计距平方法、滑动t检验、小波分析和相关分析等分析了东北地区初夏（6月）和盛夏（7—8月）降水的时空特征。结果表明：东北盛夏降水主要集中于东北东南部地区,初夏北部和东北部降水量也较多。东北初夏和盛夏降水EOF第一和第四模态分别表现为全区一致和自北向南负—正—负（正—负—正）的变化特征。初夏降水在1972年和1995年左右发生了共两次突变。盛夏降水分别在1966年、1983年和1998年左右发生了共3次突变。东北初夏降水在20世纪80—90年代存在显著的准6 a振荡周期,90年代后期开始准3 a周期较为显著;盛夏降水存在12 a左右的主振荡周期,且20世纪90年代之后3—4 a左右的年际尺度振荡周期显著。通过分时段探讨与降水相关的环流场特征,发现了东北初夏降水受东北冷涡的影响增强,盛夏降水由主要受西太平洋副热带高压影响转为受中纬西风带系统影响为主的新特征。 相似文献