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Anders Moberg Hans Bergström Josefin Ruiz Krigsman Ola Svanered 《Climatic change》2002,53(1-3):171-212
Daily meteorological observations have been made at the old astronomical observatory in Stockholm since 1754. Complete daily mean series of air temperature and sea level pressure are reconstructed from the observational data for 1756–1998. The temperature and pressure series arereconstructed and homogenized with the aid of metadata, statistical tests and comparisons with data from other stations. Comparisons with independently reconstructed daily series for nearby Uppsala (1722–1998) show that the quality of thedaily Stockholm data is good, although the reliability is lower before the mid-19th century. The daily temperature data show that the colder winter mean temperatures of the late 18th to early 19th centuries were connected with a particularly high frequency of very cold winter days. The warmer summers of the same period are more connected with a general shift of the temperature distribution towards higher temperatures than in the late 20th century. 相似文献
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Monthly mean surface pressure patterns in the European area are reconstructed for those winter and summer seasons of the 16th century with outstanding climatic anomalies being either widespread over Europe or remarkably intensive in some European regions. From the available documentary information about weather characteristics and their sequences, it proved possible to infer prevalent processes of lower tropospheric advection of typical air masses and to assess the position and strength of major surface pressure centres on a monthly scale. For comparison with modern pressure patterns, monthly mean sea level pressure (SLP) grids from the 20th century have been selected for seasons with similar climatic anomalies. There are broad coincidences between these pressure patterns of the 16th and the 20th centuries except for cold summer seasons. Finally, results from the 16th century are discussed in terms of circulation dynamics (different phases of the North Atlantic Oscillation (NAO) in winter, decreasing frequency of anticyclonic ridging in summer). 相似文献
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为了解天山和阿尔泰山长期气候变化特征，利用基于树轮资料的25条历史气候序列，集成重建了天山和阿尔泰山近150 a的年降水量和夏季气温变化情况。结果显示：20世纪上半叶是天山区域极端气候年份频现时期，而阿尔泰山极端气候年份在20世纪上下半叶分布数量相当且在19世纪下半叶相对较少。两个山系极端低值气候年份的一致性更好,且与部分历史记录吻合。天山在过去150 a内大致经历了5个偏干时期和5个偏湿时期，以及3个偏冷时期和3个偏暖时期；阿尔泰山则经历了5个偏干时期和6个偏湿时期，以及4个偏冷时期和4个偏暖时期。此外，除均存在2～6 a左右的变化周期外，天山年降水量重建序列存在27～30 a和38～39 a的变化周期，夏季平均气温重建序列存在10.5 a、53.5 a和63.7 a的变化周期；阿尔泰山夏季均温存在12.6 a的变化周期。分析表明，ENSO对天山和阿尔泰山年降水量有显著影响，而太阳黑子数与阿尔泰山夏季气温呈滞后负相关关系。 相似文献
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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
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The amplitude and rhythm of temperature changes at inter-decadal and inter-centennial timescale were studied, based on the winter-half year temperature change series reconstructed from historical phenological events in eastern China for the past 2000 years, together with the temperature change simulation from ECHO-G model for the past 1000 years, and the quasi-periods of temperature fluctuation were discussed by using wavelet analysis. The results indicate: 1) the maximal amplitude of winter half-year temperature change in eastern China at decadal and centennial scale, was above 2℃ and 0.5-1.0℃ respectively. The reconstructed result indicates that the amplitude of warming during the 20th century was identical with the maximum amplitude before the 20th century in eastern China, but the simulated result suggests that the amplitude of warming has exceeded the maximum amplitude. 2) The rhythms of temperature change at centennial to millennial scale in eastern China were about 100-year, 250-year, 400-year, 600-year and 1000-year. The 20th century, the 1st-3rd century and the 9th-13th century were warm peaks at inter-centennial scale as well as at millennial scale. It is implicated that the warming during the 20th century should be attributed to not only anthropogenic effect, but also natural climate variation. 相似文献
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The Changing Incidence of Extremes in Worldwide and Central England Temperatures to the End of the Twentieth Century 总被引：2，自引：0，他引：2
Annual and seasonal gridded ocean surface temperature anomalies show an increase in warm extremes and a decrease in cold extremes since the late 19th century attributable entirely to the overall warming trend. Over land, however, a reduction in the total incidence of extremes may reflect improved instrumental exposures. Our estimates of extremes are made by deriving percentiles from fits of anomalies on 5° latitude ×5° longitude resolution to modified 2-parameter gamma distributions. A non-parametric method is used to check the validity of the results. Fields of percentiles created using this technique can be used to map the distribution of unusual temperature anomalies across the globe on any time scale from a month to about a decade, from 1870 onwards. We apply a similar technique to assess changes in the incidence of extreme daily Central England temperature anomalies. The incidence of these extremes, relative to individual monthly average temperatures, has declined. 相似文献
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近百年气候变化与变率的诊断研究 总被引：235，自引：11，他引：235
总结了近百年来气候变化与变率的诊断研究结果，包括全球平均气温及降水量、中国平均气温及降水量，以及ＥＮＳＯ及ＱＢＯ。指出全球有变暖趋势，１９８０年代是最暖的１０年。但中国的情况有所不同，１９２０年代及１９４０年代最暖，而１９８０年代接近常年。全球降水量有增加趋势，但气温与降水的１０年尺度变化并不完全一致。１９５０年代及１９７０年代为多雨期，１９８０年代降水反而减少。中国夏季降水变化的主要特征是冷湿、暖干。１９２０年代及１９４０年代是近百年最干的时期。１８７１—１９９３年共发生厄尼诺事件２８次，拉尼娜２１次。气候变暖时厄尼诺强，气候较冷时拉尼娜频率高。１９５１—１９９３年赤道平流层纬向风准两年振荡的平均长度为２８．７个月，比１９５０年代末的估计（２６．３个月）要长。１９５１年以前的周期长度可能在２９个月左右。未发现ＱＢＯ与气候变化有明显关系。 相似文献
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本文利用中国近五百年旱涝等级资料，用典型相关的方法重建了15世纪以来的南方涛动指数（SOI）和北太平洋海温（SST）场。在SOI的重建中校准了1913—1973年校准期方差的40%，在1852—1912年的独立验证期验证了方差的20%；在北太平洋SST的重建中校准的方差较高，其中赤道东太平洋SST的校准方差达60%，在近100年的定性检验中效果也很好。说明用中国历史时期的旱涝资料能够在一定程度上重建出历史时期的ENSO事件。通过对15世纪以来SO和SST重建值的分析发现，ENSO事件不但具有明显的周期性，而且还有250年左右的阶段性变化。SO和SST不仅存在2—7年公认的周期，而且历史上SO还有10.6年、赤道东太平洋SST还有25—28.5年及100年左右与太阳活动有关的周期、进一步分析还得出，18，19世纪及20世纪前期SO低指数事件发生相对较少，15世纪后期、16、17世纪及20世纪后期SO低指数事件发生较多；且历史上的低指数多发期与气候上的冷期一致，而低指数少发期则与气候上的暖期一致；气候上的干旱（湿润）期则与东太平洋长期偏冷（暖）、西太平洋长期偏暖（冷）相对应。 相似文献
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利用国家气候中心整编的1951~2008年中国160个站的月平均气温资料,文章侧重分析了华南前汛期气温异常特征,发现:58a温度变化的总趋势是增加的,60年代中期到80年代末为相对低温期,90年代以后温度有明显升高的趋势,而且华南前汛期气温异常存在2a、4a、5a、12a和19a的周期;在近半个世纪内,我国各地区都有变暖的趋势,但是华南地区是全国4~6月气温弱增暖地区之一,华南地区4~6月普遍增暖,呈现西南强东北弱的态势,其中增暖最强的中心在广州;两个增暖最弱的中心分别在梅州和浦城。华南前汛期偏热年:华南地区低层为负距平,中、高层为正距平,这种分布形势将有利于气柱变暖,另外850hPa南海的偏南气流以及来自太平洋的东南气流加强,有利于把暖气流带到了华南地区,华南地区升温。华南前汛期偏凉年:华南地区低层为正距平,中、高层为负距平,这将造成华南前汛期温度的降低,另外850hPa来自北方的偏北气流加强,有利于把干燥寒冷的气流带到华南地区,导致华南前汛期气温偏低。 相似文献
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This paper assesses the extent to which temperature variability has increased in Austria since the late 19th century using a novel objective approach. The approach focuses on multi-day temperature episodes and isolates variability from changes in the long-term mean and seasonal variation. We define and compute three different indices of temperature variability, and find—based on 140?years of data—that temperature variability has evolved independently of mean temperature but with no long-term trend. Early 21st century’s relatively raised temperature variability level is known from late 19th century’s pre-greenhouse climate state. 相似文献
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This study presents the first 19th century cold season climate chronology for the Kingdom of Lesotho in southern Africa. The
chronology is constructed using a variety of documentary sources including letters, diaries, reports, monographs and newspaper
articles obtained from southern African and British archives. Information relating to cold season weather phenomena during
the austral autumn, winter and early spring months were recorded verbatim. Each of the cold seasons from 1833 to 1900 was
then classified as “very severe”, “severe” or “normal/mild”, with a confidence rating ranging from low (1) to high (3) awarded
against each annual classification. The accuracy of the document-derived chronology was verified against temperature data
for Maseru for the period 1893–1900. Excellent correspondence of the document-derived chronology with the Maseru instrumental
data and also with other global proxy temperature records for the 19th century is achieved. The results indicate 12 (18% of
the total) very severe, 16 (23%) severe and 40 (59%) normal/mild cold seasons between 1833 and 1900. The overall trend is
for more severe and snow-rich cold seasons during the early part of the study period (1833–1854) compared with the latter
half of the 19th century (with the exception of the 1880s). A reduction in the duration of the frost season by over 20 days
during the 19th century is also tentatively identified. Several severe to very severe cold seasons in Lesotho follow after
major tropical and SH volcanic eruptions; such years are usually characterized by early frosts, and frequent and heavy snowfalls.
The blocking of solar radiation and the enhanced northward displacement of polar fronts that are directly or indirectly associated
with volcanic events, may account for many of the most severe Lesotho winters during the 19th century. 相似文献
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The sea surface temperature （SST） anomaly of the eastern Indian Ocean （EIO） exhibits cold anomalies in the boreal summer or fall during E1 Nino development years and warm anomalies in winter or spring following the E1 Nino events. There also tend to be warm anomalies in the boreal summer or fall during La Nina development years and cold anomalies in winter or spring following the La Nina events. The seasonal phase-locking of SST change in the EIO associated with E1 Nino/Southern Oscillation is linked to the variability of convection over the maritime continent, which induces an atmospheric Rossby wave over the EIO. Local air-sea interaction exerts different effects on SST anomalies, depending on the relationship between the Rossby wave and the mean flow related to the seasonal migration of the buffer zone, which shifts across the equator between summer and winter. The summer cold events start with cooling in the Timor Sea, together with increasing easterly flow along the equator. Negative SST anomalies develop near Sumatra, through the interaction between the atmospheric Rossby wave and the underneath sea surface. These SST anomalies are also contributed to by the increased upwelling of the mixed layer and the equatorward temperature advection in the boreal fall. As the buffer zone shifts across the equator towards boreal winter, the anomalous easterly flow tends to weaken the mean flow near the equator, and the EIO SST increases due to the reduction of latent heat flux from the sea surface. As a result, wintertime SST anomalies appear with a uniform and nearly basin-wide pattern beneath the easterly anomalies. These SST anomalies are also caused by the increase in solar radiation associated with the anticyclonic atmospheric Rossby wave over the EIO. Similarly, the physical processes of the summer warm events, which are followed by wintertime cold SST anomalies, can be explained by the changes in atmospheric and oceanic fields with opposite signs to those anomalies described above. 相似文献
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环青海湖地区气温变化特征 总被引：2，自引：0，他引：2
利用刚察、海晏、共和、天峻、茶卡5站1961—2008年气温资料,分析了环青海湖地区气温变化趋势、气候突变和异常年份。结果表明：环青海湖地区平均气温具有明显的升高趋势,升幅为0.304~0.551℃/10a,各地平均气温上升幅度：南部〉东部〉西部〉北部;年、季平均气温均发生了突变,刚察、共和年平均气温在1987年发生突变,海晏在1990年出现突变,茶卡、天峻两地在1992年出现气候突变;刚察、天峻两地年平均气温在20世纪60年代中期出现异常偏低,刚察、天峻和茶卡年平均气温在2006年异常偏高,共和年平均气温在20世纪末异常偏高,季平均气温异常各地出现的年份不尽相同。 相似文献
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West Cornwall is the most south westerly part of mainland United Kingdom with a strong maritime climate. This paper analyses the earliest archived instrumental meteorological records collected in West Cornwall (SW England). Observations were obtained from the Met Office archive (Camborne 1957–2010; Culdrose 1985–2011), Trengwainton Garden (1940–2010), and from the Royal Cornwall Polytechnic Society, (data for Falmouth (1880–1952) and Helston (1843–1888)). Homogeneity tests were used (Levene and Brown-Forsythe tests) to exclude any trends not related to climate variability. The data exhibit trends in annual mean and maximum temperatures over the timescales analysed, and show a general temperature increase in the 20th and 21st century. Annual and seasonal temperature change was found to vary locally with strongly positive trends in autumn, spring and summer seasons. Trends in precipitation are positive only for the 19th century and only for one station. Correlation with the North Atlantic Oscillation (NAO) index gives negative results for precipitation data. However correlation with the NAO index is positive with temperature, especially in the winter season. Return period analysis shows a decrease in intensity and frequency of extreme precipitation events in the post-1975 period (Camborne and Trengwainton Garden stations). Climate change in the 20th century and future continued warming is likely to have major implications on biodiversity in this region. 相似文献
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F. Giorgi 《Climate Dynamics》2002,18(8):693-708
This work presents an analysis of simulated temperature and precipitation variability and trends throughout the twentieth century over 22 land regions of sub-continental scale in the HADCM3 and HADCM2 (two realizations) coupled models. Regional temperature biases in the HADCM3 and HADCM2 are mostly in the range of -5 K to +3 K for the seasonal averages and -3 K to +2 K for the annual average. Seasonal precipitation biases are mostly in the range of -50% to 75% of present day precipitation, with a tendency in both models to overpredict cold season precipitation. Except for cold season temperature in mid- and high-latitude Northern Hemisphere regions, the average climatology of the HADCM2 and HADCM3 is of comparable quality despite the lack of an ocean flux adjustment in the HADCM3. Both models show warming trends of magnitude in line with observations, although the observed inter-regional patterns of warming trend are not well reproduced. Measures of temperature and precipitation interannual to interdecadal variability in the models are in general agreement with observations except for Northern Hemisphere summer temperature variability, which is overestimated. The models somewhat underestimate the inter-decadal variations in interannual variability measures observed during the century and overestimate the range of anomalies. Both models tend to overpredict the occurrences of short persistences (1-3 years) and underpredict the occurrence and maximum length of long persistences (greater than three years), which is an indication of a deficiency in the simulation of long-lived anomaly regimes. Compared to observations, the models produce a higher magnitude of temporal anomaly correlation across regions and correlation between temperature and precipitation anomalies for a given region. This suggests that local processes that may be effective in decoupling the observed regional anomalies are not captured well. Overall, the variability measures in the HADCM2 and HADCM3 are of similar quality, indicating that the use of a flux correction in the HADCM2 does not strongly affect the regional variability characteristics of the model. 相似文献
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Tree ring inferred summer temperature variations over the last millennium in western Himalaya, India 总被引：1，自引：1，他引：0
We report the first millennium-long reconstruction of mean summer (May–June–July–August) temperature extending back to AD 940 derived from tree-ring width data of Himalayan pencil juniper (Juniperus polycarpos C. Koch) from the monsoon-shadow zone in the western Himalaya, India. Centennial-scale variations in the reconstruction reveal periods of protracted warmth encompassing the 11–15th centuries. A decreasing trend in mean summer temperature occurred since the 15th century with the 18–19th centuries being the coldest interval of the last millennium, coinciding with the expansion of glaciers in the western Himalaya. Since the late 19th century summer temperatures increased again. However, current warming may be underestimated due to a weakening in tree growth-temperature relationship noticeable in the latter part of the 20th century. Mean summer temperature over the western Himalaya shows a positive correlation with summer monsoon intensity over north central India. Low-frequency variations in mean summer temperature anomalies over northwestern India are consistent with tree-ring inferred aridity in western North America. These far-distance linkages reported here for the first time underscore the utility of long-term temperature records from the western Himalayan region in understanding global-scale climatic patterns. 相似文献
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A. A. Isaev 《Russian Meteorology and Hydrology》2007,32(9):576-580
The phenomenon of the abnormally warm winter and cold season of 2006/07 accompanied by record high and long-lasting anomalies of air and soil temperature, precipitation, snow depth, and other meteorological variables relative to estimates of the previous seasons from the end of the 19th to the beginning of the 21st century is diagnozed. 相似文献
20.
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