共查询到20条相似文献，搜索用时 15 毫秒
1.
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
2.
1997年全球重大气候事件概述 总被引：1，自引：0，他引：1
近年来,全球气候持续偏暖,１９９７年又成为一个多世纪以来最暖的一年。年内赤道中、东太平洋发生了一次本世纪最强的厄尔尼诺事件,全球气候受到重大影响,特别是热带地区出现了大范围的气候异常,高温干旱、暴雨洪水事件此起彼伏,连续不断,造成严重灾害。欧洲、北美前冬和春季严寒多雪;欧洲夏季暴雨频繁,中欧发生了百年不遇的特大洪水;中国北部和朝鲜出现罕见的持续高温干旱天气;美国和加拿大边境地区发生了一百多年来最严 相似文献
3.
全球气候仍为异常暖年。赤道中、东太平洋形成新的ENSO暖事件。冬季前期连续大雪严寒席卷了欧洲大部地区，美国南部也受到罕见大雪袭击。南亚东部、中南半岛湄公河三角洲雨季降水频繁，引发严重洪涝灾害。8月，欧洲异常暴雨引发世纪大洪水，多国受灾严重。印度尼西亚、澳大利亚、美国西部、非洲大部降水持续偏少，发生严重干旱。太平洋、大西洋的热带风暴给沿岸国家带来不同程度的灾害。 相似文献
4.
This paper analyses the role played by the North Atlantic Oscillation (NAO) in the creation of drought conditions in a semi-arid
region of north-east Spain (the middle Ebro valley), from 1600 to the year 2000. The study used documents from ecclesiastical
archives for the seventeenth, eighteenth and nineteenth centuries. For the twentieth century, instrumental precipitation records
were used as well. A December–August drought index from 1600 to 1900 was compiled from the historical documentary sources
(rogation ceremonies). The index was validated by means of precipitation records between 1858 and 1900 and independent precipitation
data from 1600 reconstructed by means of dendrochronological records. Using instrumental data a drought index was also calculated
(Standardized Precipitation Index, SPI) for the 1958–2000 period. We found that the NAO was important in explaining the droughts
identified in the study area from documents and instrumental data. Positive values of the winter NAO index are prone to cause
droughts in the middle Ebro valley. This finding has been verified since 1600 by means of two independent reconstructions
of the winter NAO index. The same behaviour has been observed during the nineteenth and twentieth centuries by means of instrumental
records. The climatic and geographic factors that explain the high influence of North Atlantic Oscillation on droughts in
this region are discussed in depth. 相似文献
5.
D. RETSÖ 《Climatic change》2002,52(1-2):137-173
In this paper, the potential is explored for climatological information on winter weather in a hitherto largely neglected category of historical documentary sources (correspondence letters) covering two decades of the less studied intermediate stages between the proposed warm High Middle Ages and what has been termed `the Little Ice Age'. A discussion concerning some problems of interpretation is presented from a historical methodological point of view. Content analysis, with special attention paid to contemporary terms and expressions linked to transport and travel, shows that winters in Sweden during the first decades of the sixteenth century, in comparison with the average of the late twentieth century, were on the whole somewhat shorter in duration. Two of the winters studied can be said to display some extreme characteristics; one exceptionally mild, and one with an unusually early onset. On the whole, the result diverges slightly from previously published winter severity indices and confirms regional disparities in the middle phase between a possible warm High Middle Ages and the so-called `Little Ice Age'. 相似文献
6.
Characteristics of anomalous precipitation events over eastern China during the past five centuries 总被引：3，自引：0，他引：3
Characteristics of anomalous precipitation events during the past five centuries in North China (NC) and the middle-lower
Yangtze River Valley (MLYRV) were investigated using the data network of dryness/wetness index (DWI) over eastern China. The
high occurrence frequency of anomalous precipitation events mainly occurred at periods of high solar forcing, active volcanic
eruption, and large anthropogenic forcing (the twentieth century). Coherence and dipole were the two dominant modes in spatial
patterns of anomalous precipitation events. Coherent floods dominated the eighteenth and nineteenth centuries, whereas coherent
droughts occurred frequently in the seventeenth and twentieth centuries. The dipole patterns of anomalous precipitation events
were the most frequent in the twentieth century. NC experienced more floods in the cold periods than warm periods. Both NC
and the MLYRV experienced far fewer droughts and more floods in the warm eighteenth century when natural climate forcing dominated,
and more droughts in the twentieth century when anthropogenic forcing dominated. Coherent drought was the only spatial pattern
of precipitation significantly associated with explosive low-latitude volcanic eruptions. The increased coherent droughts
and dipole patterns in the twentieth century support the findings of previous modeling studies that the tropospheric aerosols
and human-induced land cover changes play important roles in the changes of summer rainfall over eastern China.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
This paper is a contribution to the AMIP-CMIP Diagnostic Sub-project on General Circulation Model Simulation of the East Asian
Climate, coordinated by W.-C. Wang. 相似文献
7.
１９９３年,是世界异常气候事件突出的年份。美国东部春季的“世纪暴风雪”,中西部夏季的特大洪水,日本和中国黄淮,江淮地区罕见的“低温”凉夏,巴西东北,澳大利亚东部严重的干旱,大西洋加勒比海地区猛烈的飓风以及西欧秋冬的洪水……,种种异常天气气候事件,多与热带太平洋１９９２年夏曾宣告结束,而１９９３年春再度发生,并持续至今的厄尔尼诺现象,以及中高纬地区年内多数朋份大气环流的经向型紧密相关。 相似文献
8.
The periods from 1675–1715 (Late Maunder Minimum; LMM)and 1780–1830 (Early Instrumental Period; EIP)delineate important parts of the so-called `Little IceAge' (LIA), in which Europe experienced predominantcooling. Documentary data, assembled from a number ofsources, in the course of the EU funded researchproject ADVICE (Annual to Decadal Variability ofClimate in Europe), has been used to locate anddescribe events in the southern Balkans and easternMediterranean. The resulting data has been usedfirstly to investigate the incidence of phenomena suchas crops sterility, famine and epidemics and theirrelationships with climate, and secondly to analysethe extent of variability, particularly the occurrenceof extreme events, such as severe winters (cold, wetor snowy), long periods of drought and wet periods.During the LMM and EIP, more such extreme situationswere apparent compared with the last 50 years of thetwentieth century. From the scattered data found for1675–1715 and 1780–1830, the winter and spring climatein southern Balkans and the eastern Mediterranean,especially during the LMM, can be characterised ascooler and relatively rainier with a highervariability compared with the recent decades. 相似文献
9.
David Barriopedro David Gallego M. Carmen Alvarez-Castro Ricardo García-Herrera Dennis Wheeler Cristina Peña-Ortiz Susana M. Barbosa 《Climate Dynamics》2014,43(3-4):939-955
A monthly index based on the persistence of the westerly winds over the English Chanel is constructed for 1685–2008 using daily data from ships’ logbooks and comprehensive marine meteorological datasets. The so-called Westerly Index (WI) provides the longest instrumental record of atmospheric circulation currently available. Anomalous WI values are associated with spatially coherent climatic signals in temperature and precipitation over large areas of Europe, which are stronger for precipitation than for temperature and in winter and summer than in transitional seasons. Overall, the WI series accord with the known European climatic history, and reveal that the frequency of the westerlies in the eastern Atlantic during the twentieth century and the Late Maunder Minimum was not exceptional in the context of the last three centuries. It is shown that the WI provides additional and complementary information to the North Atlantic Oscillation (NAO) indices. The analysis of WI series during the industrial era indicates an overall good agreement with the winter and high-summer NAO, with the exception of several multidecadal periods of weakened correlation. These decoupled periods between the frequency and the intensity of the zonal flow are interpreted on the basis of several sources of non-stationarity affecting the centres of the variability of the North Atlantic and their teleconnections. Comparisons with NAO reconstructions and long instrumental indices extending back to the seventeenth century suggest that similar situations have occurred in the past, which call for caution when reconstructing the past atmospheric circulation from climatic proxies. The robustness and extension of its climatic signal, the length of the series and its instrumental nature make the WI an excellent benchmark for proxy calibration in Europe and Greenland. 相似文献
10.
Freezing of the Venetian Lagoon since the 9th century A.D. in comparision to the climate of western Europe and England 总被引：2，自引：0，他引：2
Dario Camuffo 《Climatic change》1987,10(1):43-66
In the first part of this study, typical of historical climatology, the various sources regarding freezing of the Venetian Lagoon since the 9th century A.D., are reported and discussed. The events are related, where possible, to teleconnections. Two synoptic patterns (weather type A: northerly and D: easterly) seem to have played an important role. After having discussed the dynamics of the icing processes, the problem of comparing the data is considered, as over the centuries many works were made on the Lagoon, in order to divert the major tributaries. In fact, the hydrological regime and the physical characteristic of the Lagoon environment were changed, so that the conditions necessary for freezing were no longer the same. The series was compared with the severe winters in westtern Europe and England, in order to reconstruct the past climate of the Mediterranean region and discuss the observed secular changes in the light of the widely accepted ideas of climatic variations. The comparison shows some differences: e.g. at Venice the Medieval Climatic Optimum with the occurrence of severe winters ended earlier and the Little Ice Age was broken by a milder interval. 相似文献
11.
A.T. Grove 《Climatic change》2001,48(1):121-136
Alpine glacier advances in the "Little Ice Age" took place in the decades around 1320, 1600, 1700 and 1810. They were the outcome of snowier winters and cooler summers than those of the twentieth century. Documentary records from Crete in particular, and also from Italy, southern France and southeast Spain point to a greater frequency in Mediterranean Europe's mountainous regions of severe floods, droughts and frosts at times of "Little Ice Age" Alpine glacier advances. Deluges, when more than 200 mm of rain fall within 24 hours, are most frequent on mountainous areas near the coast. An instance is given of the geomorphological consequences of a great deluge which struck the Tech valley in the eastern Pyrenees on 17 October 1940. An increased frequency of deluges, probably at times when Alpine glaciers were advancing in the "Little Ice Age" and earlier in the Holocene, in areas known to be tectonically unstable and underlain by soft sediments, could better explain the occurrence of fluvial terraces in Mediterranean Europe sometimes known as the "younger fill", than soil erosion resulting from deforestation. 相似文献
12.
Impact of recent climatic change on growth of low elevation eastern Mediterranean forest trees 总被引：3，自引：1，他引：2
Evidence is presented of how Pinus halepensis Miller from dry habitats at <300 m elevation of four Greek island regions have responded to climatic conditions of the last two centuries. We compared historical periods of low growth due to low precipitation with the recent period of significant precipitation decline. In all cases trees?? growth patterns across the twentieth century were consistent with trends in annual (rather than seasonal) precipitation, with lowest values in both precipitation and radial growth during the last two decades of the twentieth century, the worst conditions for tree growth in more than 200 years. The data are compared with trends across different vegetation belts of the northern Mediterranean basin. Drought related tree mortality in Greece in 2000 and 2007 coincided with the most severe fire outbreaks on record. IPCC WG I (2007) climate scenarios for the Mediterranean suggest a further decline in precipitation, particularly in the eastern regions. Should this occur, growth reduction in trees, tree mortality and damage from forest fires are likely to become more severe. 相似文献
13.
Trends in flood seasonality of the River Ouse (Northern England) from archive and instrumental sources since AD 1600 总被引：1，自引：0，他引：1
Neil Macdonald 《Climatic change》2012,112(3-4):901-923
The last decade has witnessed an increase in the application of historical records (historical and documentary) in developing a more complete understanding of high-magnitude flood frequency; but little consideration has been given to the additional information that documentary accounts contain, particularly relating to flood seasonality. This paper examines the methods and approaches available in long-term flood seasonality analysis and applies them to the River Ouse (Yorkshire) in Northern England since AD 1600. A detailed historical flood record is available for the City of York consisting of annual maxima flood levels since AD 1877, with documentary accounts prior to this. A detailed analysis of long-term flood seasonality requires confidence in the accuracy and completeness of flood records; as a result the augmented flood series are analysed using three strategies: firstly, considering all recorded floods since AD 1600; secondly, through detailed analysis of the more complete record since AD 1800; and finally, applying a threshold to focus on high-magnitude flood events since AD 1800. The results identify later winter flooding, particularly in the second half of the twentieth century, with a notable reduction in summer flood events at York during the twentieth century compared to previous centuries. Flood generating mechanisms vary little between the periods considered, with a general pattern of stability in the ratio of floods incorporating a snowmelt component. 相似文献
14.
E. Hertig S. Seubert A. Paxian G. Vogt H. Paeth J. Jacobeit 《Theoretical and Applied Climatology》2013,111(1-2):1-20
Changes of total precipitation, extreme precipitation, and dry periods in the Mediterranean area until the end of the twenty-first century have been assessed by means of statistical downscaling. Generalized linear models using predictors describing the large-scale atmospheric circulation as well as thermodynamic conditions have been applied for the projections under A1B and B1 scenario assumptions. The results mostly point to reductions of total and extreme precipitation over the western and central-northern Mediterranean areas in summer and autumn and to increases in winter. In contrast, over the eastern Mediterranean area widespread precipitation increases are assessed in summer and autumn, whereas reductions dominate in winter. In spring, total and extreme precipitation decreases prevail over the whole Mediterranean area. Total and extreme precipitation decreases mostly come along with increases of the maximum dry period length. Vice versa precipitation increases are commonly accompanied by a shortening of the maximum dry period length. 相似文献
15.
The study of climatic anomalies on the basis of various types of instrumental information and proxy-data allows unusual events to be identified. The objective of this paper is to introduce and explain a hydrometeorological anomaly that occurred between 1760 and 1800 (Maldá Anomaly), characterised by a sequence of both anomalous droughts and floods, and to compare it with the features of the second part of the 20th century. Firstly, some climatic indices obtained from proxy-data (mainly documentary sources) have been generated. Secondly, instrumental observations made in earlier times, in conjunction with data from the bibliography, have been used in order to relate this period to the different circulation patterns and to analyse the geographical extension of the anomaly. The results confirm the presence of considerable variations in the atmospheric action centres, especially between 1780 and 1795, which in the Western Mediterranean gave rise to a simultaneous increase in the frequency of droughts and heavy rainfalls, either having nothing comparable or sharing similarities with periods in the 19th and 20th centuries. 相似文献
16.
中国夏季和冬季极端干旱年代际变化及成因分析 总被引：4，自引：0，他引：4
依据1961～2009年中国区域540个气象站的夏、冬季气温和降水数据,首先采用气候变化趋势转折判别模型（简称PLFIM）分析了中国区域8个分区夏、冬季气温和降水的年代际变化,而后利用PDSI干旱指数研究了夏、冬季极端干旱在年代际尺度上的时空变化特征及其成因。结果表明:1961～2009年中国夏季极端干旱发生率北方大于南方,冬季则为在东部多而在西部少。夏季和冬季极端干旱发生概率在最后一次年代际转折后都呈增加趋势。在区域尺度上,夏季东北、华北和西北地区增加明显,冬季东北、华北、华南、西南地区增加显著。其中,降水在20世纪90年代以前的极端干旱变化中起主导作用,而后由于气候变暖所引起的极端干旱增加趋势逐渐增大,与降水变化的作用相互叠加。 相似文献
17.
B. G. Hunt 《Climate Dynamics》2011,37(7-8):1501-1515
Output from a multi-millennial simulation with the CSIRO Mark 2 coupled global climatic model has been analysed to determine the principal characteristics of extreme winters over the globe for ??present conditions??. Thus, this study is not concerned with possible changes in winter conditions associated with anthropogenically induced climatic change. Defining an extreme winter as having a surface temperature anomaly of below ?2 standard deviations (sd) revealed a general occurrence rate over the globe of between 100 and 200 over a 6,000-year period of the simulation, with somewhat higher values over northwest North America. For temperature anomalies below ?3?sd the corresponding occurrence rate drops to about 10. Spatial correlation studies revealed that extreme winters over regions in Europe, North America or Asia were very limited geographically, with time series of the surface temperature anomalies for these regions having mutual correlation coefficients of about 0.2. The temporal occurrence rates of winters (summers) having sd below ?3 (above +3) were very asymmetric and sporadic, suggesting that such events arise from stochastic influences. Multi-year sequences of extreme winters were comparatively rare events. Detailed analysis revealed that the temporal and spatial evolution of the monthly surface temperature anomalies associated with an individual extreme winter were well replicated in the simulation, as were daily time series of such anomalies. Apart from an influence of the North Atlantic Oscillation on extreme winters in Europe, other prominent climatic oscillations were very poorly correlated with such winters. Rather modest winter temperature anomalies were found in the southern hemisphere. 相似文献
18.
1955—2014年杭州极端气温和降水指数变化特征 总被引：1，自引：0，他引：1
根据杭州市1955—2014年降水量、气温逐日资料,采用国际通用的极端天气指数和线性倾向估计、M-K检验等方法,分析了杭州市近60 a极端气温和降水的变化特征。结果表明：1）杭州市近60 a的气温呈一致升高趋势,且变化显著,表现为极端高温阈值和极端低温阈值的升高及极端高温日数的增多;极端冷事件显著减少,暖事件显著增多。2）极端降水指数中只有强降水量的增加较明显,主要贡献为夏季和冬季强降水量的增强。3）冬季平均气温、极端低温阈值、霜冻日数等极端冷事件的突变发生于20世纪80年代初中期,夏季平均气温、极端高温阈值、高温日数等极端暖事件的突变发生于20世纪末21世纪初,与全国范围内的气候增暖进程基本一致。另外,降水强度、极端降水阈值等极端降水指数的突变时间在2008年左右,即2008年后气温升高和降水强度的增加突变期叠加,尤其在夏季和冬季表现更突出,可能诱发更多的异常天气。 相似文献
19.
J. Fuhrer M. Beniston A. Fischlin Ch. Frei S. Goyette K. Jasper Ch. Pfister 《Climatic change》2006,79(1-2):79-102
There is growing evidence that, as a result of global climate change, some of the most severe weather events could become more frequent in Europe over the next 50 to 100 years. The paper aims to (i) describe observed trends and scenarios for summer heat waves, windstorms and heavy precipitation, based on results from simulations with global circulation models, regional climate models, and other downscaling procedures, and (ii) discuss potential impacts on agricultural systems and forests in Switzerland. Trends and scenarios project more frequent heavy precipitation during winter corresponding, for example, to a three-fold increase in the exceedance of today's 15-year extreme values by the end of the 21st century. This increases the risk of large-scale flooding and loss of topsoil due to erosion. In contrast, constraints in agricultural practice due to waterlogged soils may become less in a warmer climate. In summer, the most remarkable trend is a decrease in the frequency of wet days, and shorter return times of heat waves and droughts. This increases the risk of losses of crop yield and forage quality. In forests, the more frequent occurrence of dry years may accelerate the replacement of sensitive tree species and reduce carbon stocks, and the projected slight increase in the frequency of extreme storms by the end of the century could increase the risk of windthrow. Some possible measures to maintain goods and services of agricultural and forest ecosystems are mentioned, but it is suggested that more frequent extremes may have more severe consequences than progressive changes in means. In order to effectively decrease the risk for social and economic impacts, long-term adaptive strategies in agriculture and silviculture, investments for prevention, and new insurance concepts seem necessary. 相似文献
20.
It has frequently been suggested that the period encompassing the ninth to the fourteenth centuries A.D. experienced a climate warmer than that prevailing around the turn of the twentieth century. This epoch has become known as theMedieval Warm Period, since it coincides with the Middle Ages in Europe. In this review a number of lines of evidence are considered, (including climatesensitive tree rings, documentary sources, and montane glaciers) in order to evaluate whether it is reasonable to conclude that climate in medieval times was, indeed, warmer than the climate of more recent times. Our review indicates that for some areas of the globe (for example, Scandinavia, China, the Sierra Nevada in California, the Canadian Rockies and Tasmania), temperatures, particularly in summer, appear to have been higher during some parts of this period than those that were to prevail until the most recent decades of the twentieth century. These warmer regional episodes were not strongly synchronous. Evidence from other regions (for example, the Southeast United States, southern Europe along the Mediterranean, and parts of South America) indicates that the climate during that time was little different to that of later times, or that warming, if it occurred, was recorded at a later time than has been assumed. Taken together, the available evidence does not support aglobal Medieval Warm Period, although more support for such a phenomenon could be drawn from high-elevation records than from low-elevation records.The available data exhibit significant decadal to century scale variability throughout the last millennium. A comparison of 30-year averages for various climate indices places recent decades in a longer term perspective. 相似文献