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1.
英国CRU高分辨率格点资料揭示的20世纪中国气候变化   总被引:29,自引:1,他引:29  
中国覆盖比较完整的台站观测始于1951年,1951年之前虽然有一些观测记录,但是残缺不全.所以要建立更长的气候序列就要吸收代用资料,但是代用资料可能与气候要素仅有一定程度的相关,不可能一一对应,因此应用代用资料重建的气候序列有一定的不确定性.英国East Anglia大学的Climatic Research Unit(简称CRU)通过整合已有的若干个知名数据库,重建了一套覆盖完整、高分辨率、且无缺测的月平均地表气候要素数据集,时间范围覆盖1901~2003年,空间为0.5°×0.5°经纬网格覆盖所有陆地.这套资料和中国已有的气候数据相比具有如下优点: 第一,中国西部20世纪前半期非常缺少观测,CRU资料尽管包含插值带来的误差,经比较仍可作为有一定信度的参考; 第二,中国现有的百年温度序列只是年或季分辨率,而CRU资料达到月分辨率; 第三,建立这个序列仅使用观测结果,做统计内插,不包括代用资料所带来的不确定性.因此,CRU的序列与用代用资料补充得到的序列在资料方面有较大不同,比较这两个序列,不仅可以进一步确认中国气候变化的特征,也可以彼此校正.结果表明:(1)CRU资料反映的全国年平均温度年际变化和考虑代用资料重建的序列吻合得很好,相关系数达到0.84;(2)区域尺度上,两者在10个典型分区的气温变率也相当一致,相关整体保持在0.8左右,仅新疆西南部和西藏西北部两者差异较大;(3)CRU资料揭示的中国年总降水量在1951~2000年的变化与160站观测吻合,相关系数达到0.93;(4)CRU资料的中国东部四季降水量和重建资料十分一致,秋季一致性最好,相关0.93;(5)CRU资料和重建的序列比较一致地表现出中国温度和降水年代际变化的主要特征,其给出的20世纪20年代中国大旱和20世纪40年代中国高温的空间分布与作者过去的结论相一致.这表明,作者过去重建的中国气候序列有比较大的可靠性,而CRU资料也提供了新的信息,特别是在20世纪前半期和中国西部.  相似文献   

2.
中国气温变化研究最新进展   总被引:231,自引:9,他引:222  
总结了"十五"攻关课题有关中国温度变化研究的若干进展.在资料质量控制和序列非均一性检验及订正的基础上,更新了中国地面近50年、100年和1 000年气温序列.研究表明,不论是近54年还是近100年全国年平均地面气温升高趋势一般比原来分析结果表明的要强,分别达到0.25℃/10 a和0.08℃/10 a.中国现代增暖最明显的地区包括东北、华北、西北和青藏高原北部,最显著的季节在冬季和春季.近50多年中国近地面气候变暖主要是平均最低气温明显上升的结果,全国范围内极端最低气温也显著升高,而极端最高气温升高不多.中国与温度相关的极端气候事件强度和频率一般呈降低趋势或稳定态势.研究发现,城市化因素对中国地面平均气温记录具有显著影响,但在现有的全国和区域平均温度变化分析中一般没有考虑,因此需要在将来的研究中给予密切关注.在增温明显的华北地区,1961~2000年间城市化引起的年平均气温增加值达到0.44℃,占全部增温的38%,城市化引起的增温速率为0.11℃/10 a.中国其他地区的增温趋势中也或多或少反映出增强的城市热岛效应影响.20世纪60年代初以来中国对流层中下层温度变化趋势不明显,仅为0.05℃/10 a,比地面气温变化小一个量级;对流层上层和平流层底层年平均温度呈明显下降趋势,变化速率分别为-0.17℃/10 a和-0.22℃/10 a;整个对流层平均温度呈微弱下降趋势.中国对流层温度与地面气温变化趋势存在明显的差异,但这种差异在20世纪80年代初以后趋于减小.近千年来中国地面气温变化史上可能确存在"中世纪温暖期"和"小冰期"等特征性气候阶段,但"中世纪温暖期"的温暖程度似乎没有过去认为的那样明显.从全国范围看,11世纪末和13世纪中的温暖程度可能均超过了20世纪30~40年代暖期,表明20世纪的增暖可能并非史无前例.中国20世纪气候增暖的原因目前还不能给出明确回答.一些迹象表明,人类活动可能已经对中国的地面气温变化产生了影响,但太阳活动及气候系统内部的低频振动对现代气候变暖可能也具有重要影响.  相似文献   

3.
利用参与第三次古气候模式评估比较计划(Paleoclimate Modelling Intercomparison Project Phase III,PMIP3)过去千年气候模拟试验以及参与第五次耦合模式评估比较计划(Paleoclimate Model Intercomparison Project Phase 5,CMIP5)全强迫历史情景试验的9个地球系统模式模拟试验结果,对过去千年3个特征时段(中世纪气候异常期、小冰期和现代暖期)北极涛动(Arctic Oscillation, AO)的变率及成因进行了分析。通过与NCEP再分析资料的对比发现,模式能够较好地模拟出AO的空间模态及年际变化周期,且大部分模式能够模拟出过去50年AO的增强趋势。过去千年3个特征时段中,不同模式对中世纪气候异常期AO位相的模拟并不一致,但大部分模式显示小冰期AO基本呈现负位相,而现代暖期则表现为显著的正位相,与重建结果一致。基于多模式集合平均的机制分析表明,中世纪气候异常期北极地区海平面气压变化不显著,小冰期北极地区海平面气压显著偏正,现代暖期海平面气压显著偏负,这与现代暖期北极温度偏高而小冰期北极温度偏低有关。过去千年中,小冰期和现代暖期的AO变率分别受自然外强迫和人为外强迫的影响。  相似文献   

4.
柴达木盆地东北部过去1437 a的降水变化重建   总被引:24,自引:0,他引:24       下载免费PDF全文
利用青海柴达木盆地东北缘山地11个地点的祁连圆柏树轮宽度序列,在早期分析祁连圆柏的生长对气候要素响应的基础上,重建了青海德令哈和乌兰地区过去1437 a的年降水量变化序列。重建方程能够解释校准期(1955-2002年)内66%的降水量变化方差,尤其是重建的降水序列的低频变化能够很好地代表器测资料的变化。从过去1437 a的时间尺度来看,近40 a来柴达木东北缘地区处于相对湿润的时期,但最显著的湿润期出现在16世纪晚期。此外,小冰期期间降水量的变幅较大,而中世纪暖期降水低频变化相对较小。另外,重建降水量体现了150~250 a尺度的低频变化特征。  相似文献   

5.
本文在对15世纪以来湖南洞庭湖地区的地方志等史料进行整理、甄别的基础上,以严冬年出现的次数作为每10年冬季温度平均状况的指标,研究了15世纪后半叶至19世纪末期该区域冬季温度的变化,发现该区域以17世纪最冷,19世纪次之,15世纪后半叶亦偏冷,而16世纪显著偏暖,18世纪冷暖期相间但以暖期为主。通过 t-检验等方法,对该区域近80年来的观测资料进行了统计分析,得知该区域气候变化的趋势为前期偏冷、中期暖冷相间、后期略偏暖至正常,反映了湖区气候变化除某些与大范围区域的气候变化相一致外,还具有自身的特点。这在一定程度上,可能还与湖泊效应有关。  相似文献   

6.
本文探讨了利用乌兰多个树木年轮年表的信息,异地重建沱沱河冬季1—3月气温的途径和方法,重建了沱沱河800年气温序列,结果表明:重建的冬季气温序列的主要冷、暖期与已有成果基本吻合,13、15、17世纪的冷期以及14、16世纪的暖期是存在的,而17世纪的寒冷期持续时间最长,寒冷程度也最强。本文对重建的气温序列的阶段性、突变和周期进行了初步的统计分析,为青藏铁路工程沿线气候演变提供背景资料。  相似文献   

7.
基于中国东部地区(30°—40°N,105°E以东)19个代表站1470—2019年旱涝等级序列、古气候代用资料定量重建的北太平洋海表温度年代际振荡指数以及Nino3.4指数,通过经验正交函数分解、小波分析和集合经验模态分解方法分析了中国东部旱涝年代际变化特征及其与太平洋海温的关系。结果表明,(1)1470年以来中国东部旱涝变化的主模态为全区一致型(方差贡献率为25.2%),变率中心主要位于黄河中下游,其时间系数的小波分析和集合经验模态分解揭示出全区旱涝存在10—30 a的准周期;该模态长期趋势揭示17—18世纪中国东部整体偏涝,而19世纪以后出现干旱化趋势。(2)寒冷背景下中国东部旱涝一致变化更明显,在17世纪前、中期和19世纪中、后期的小冰期寒冷期全区一致型模态的方差贡献率为35%—40%,且这两个时段10—30 a的年代际变化信号尤为显著;而旱涝的变率中心则表现出冷期偏北,暖期偏南或偏西的特征。(3)中国东部旱涝的年代际变化与北太平洋和赤道中东太平洋海表温度异常有关,表现为偏涝(旱)气候对应于北太平洋海表温度年代际振荡的冷(暖)相位,以及年代际尺度上的冬季Nino3.4区海表温度的异常偏低(高);在小冰期的寒冷期,旱涝的年代际变化可能与Nino3.4区海表温度异常关系更密切。   相似文献   

8.
利用乌兰树木年轮重建托托河冬季气温序列   总被引:23,自引:9,他引:14  
探讨了利用乌兰多个树木年轮年表的信息,异地重建托托河站冬季1~3月气温的途径及方法,重建了托托河800多年气温序列。结果表明,重建的冬季气温序列的主要冷、暖期与已有结果基本吻合,13、15和17世纪的冷期及14和16世纪的暖期是存在的,而17世纪的寒冷期持续时问最长,寒冷程度也最强。本文对重建气温序列的阶段性、突变和周期进行了初步的统计分析,为青藏铁路工程沿线气候演变提供背景资料。  相似文献   

9.
近千年青藏高原的温度变化   总被引:7,自引:0,他引:7       下载免费PDF全文
通过对昌都树轮d13C、达索普冰芯d18O和先前重建的整个高原温度序列的分析,以及与其他气候代用记录的比较,揭示了青藏高原近1000 a来的温度变化特征。依据昌都树轮d13C年表,指出青藏高原的中世纪暖期发生于1200-1400 AD,该时期的夏季温度比长期平均值或现代(20世纪,下同)约高1.2℃,小冰期(1400-1700 AD)的夏季温度比长期平均值或现代约低0.5℃。近1000 a最暖的时期是13世纪,而最冷的时期是1000-1200 AD,温度比现代约低0.9℃。20世纪的气候变暖主要表现在冬季温度的升高,同期的夏季温度呈微弱的下降趋势。  相似文献   

10.
一些水文气候资料分析表明,美国西部正在经历着多年的严重干旱。然而,利用重建的覆盖美国西部大部分地区的过去1200年的网格化干旱资料进行分析,看出与更早时期出现的极端干旱和发生在公元800~1300年间(中世纪暖期(MWP))的大范围严重干旱相比,现在正经历的干旱还不算很严重。如果美国西部干旱程度的加强是一种对气候变暖的自然响应,那么任何将来温度增暖的趋势都将会加剧美国西部地区的长期干旱。  相似文献   

11.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

12.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.  相似文献   

13.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

14.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  相似文献   

15.
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.SUBMISSIONAll submitted  相似文献   

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<正>With the support of specialized funds for national science institutions,the Guangzhou Institute of Tropical and Marine Meteorology,China Meteorological Administration set up in October 2008 an experiment base for marine meteorology and a number of observation systems for the coastal boundary layer,air-sea flux,marine environmental elements,and basic meteorological elements at Bohe town,Maoming city,Guangdong province,in the northern part of the South China Sea.  相似文献   

18.
《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

19.
《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome.  相似文献   

20.
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences  相似文献   

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