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1.
ENSO及其年代际异常对全球及亚洲季风降水影响的数值研究 总被引：22，自引：5，他引：17
根据诊断分析结果,利用ＬＡＧＳ改进的Ｌ９Ｒ１５气候谱模式,设计了３个数值试验,讨论了不同的年代际背景下ＥＮＳＯ异常对全球降水,特别是对亚洲季风降水的影响。试验结果表明,在年代际的冷、暖背景下,当出现ＥＮＳＯ事件时,降水响应的异常场在ＥＮＳＯ的不同发展阶段上,表现显著不同。出现这种差异的物理过程可以用与垂直环流相联系的势函数的变化来表示。暖背景下,当ＥＮＳＯ处于发展时期,比冷背景下更容易出现强烈反Ｗａｌｋｅｒ的环流,但在ＥＮＳＯ处于衰减期更容易产生强烈的Ｗａｌｋｅｒ环流,这就意味着暖背景时的ＥＮＳＯ异常对大气影响的幅度更大。 相似文献
2.
ENSO对亚洲夏季风异常和我国夏季降水的影响 总被引：21，自引：11，他引：21
首先对ＥＮＳＯ过程中亚洲夏季风环流的变化进行了诊断分析，结果表明在Ｅｌ Ｎｉｎｏ事件和ＬａＮｉｎａ事件中亚洲夏季风系统各成员均发生不同程度的变化，甚至出现相反的变异特征。其中，对我国东部地区夏季降水进行了ＥＯＦ分析，并在此基础上分析了赤道太平洋ＳＳ－ＴＡ对我国东部地区夏季降水影响的区域和程度，该影响与ＥＮＳＯ循环的发展阶段密切相关，且在长江中下游地区和华南地区最为显著。 相似文献
3.
喜马拉雅山南坡冬季暴雪对高原南部冰芯中稳定同位素记录的影响 总被引：3，自引：0，他引：3
聂拉木气象站降水中 δ18O的变化表明 ,夏季降水中 δ18O为一低值阶段 ;冬季降水中 δ18O总的来说为一高值阶段 ,但冬季暴风雪中δ18O的值和夏季强的季风活动中降水的δ18O一样很低。由于该地区冬季降水十分活跃 ,冬季降水中 δ18O的变化对该地区冰芯记录将产生重要的影响。首先是用δ18O的季节变化来对冰芯定年产生一定的困难 ,其次喜马拉雅山中段冰芯中的δ18O记录不仅包括了夏季季风活动的强弱信息 ,而且冬季强的暴风雪过程也记录在内。 相似文献
4.
ENSO与宁夏夏季降水关系的分析 总被引：6，自引：0，他引：6
文中计算了太平洋地区各月海温距平与宁夏６、７、８月降水指数的相关,发现各月的高相关区在时间和空间上有所不同,分析了９次ＥＮＳＯ当年和次年宁夏各月降水变化的总体特征,发现宁夏夏季降水ＥＮＳＯ当年偏少,偏少程度占年偏少的６５％～７９％;ＥＮＳＯ次年偏多,偏多程度占年的５９．２％～８７．９％。对宁夏夏季降水和ＮＩＮＯ指数的谱分析发现,宁夏６月降水没有明显周期,７月降水存在１５年和３年左右的周期,８月降水只有３年周期,ＮＩＮＯ指数存在３．７５年左右的周期。对凝聚谱和位相谱值的分析结果表明,赤道东太平洋地区海温变化超前宁夏夏季降水变化１．６７年,这就为宁夏的夏季降水长期预报提供了依据。 相似文献
5.
利用我省４２年逐日降水资料和国家ＥＮＳＯ监测小组所划分的建国以来的ＥＩＮｉｎｏ事件,分析ＥＩＮｉｎｏ事件当年及次年山西降水的分布特征。结果表明,我省降水与ＥＩＮｉｎｏ事件密切,ＥＩＮｉｎｏ事件当年与次年,山西降水分布特征具有相反性,而且,春夏两季的相反趋势更为明显。 相似文献
6.
GROUND-BASED MEASUREMENTS OF COLUMN ABUNDANCE OF OZONE AN 总被引：1，自引：0，他引：1
ＧＲＯＵＮＤ－ＢＡＳＥＤＭＥＡＳＵＲＥＭＥＮＴＳＯＦＣＯＬＵＭＮＡＢＵＮＤＡＮＣＥＯＦＯＺＯＮＥＡＮＤＵＶ－ＢＲＡＤＩＡＴＩＯＮＯＶＥＲＺＨＯＮＧＳＨＡＮＳＴＡＴＩＯＮ，ＡＮＴＡＲＣＴＩＣＡＦＯＲＴＨＥ１９９３“ＯＺＯＮＥＨＯＬＥ”ＺｈｏｕＸｉｕｊｉ... 相似文献
7.
《中国气象科学研究院年报》1995,(1)
ＤＲＡＦＴＰＲＯＰＯＳＡＬＦＯＲＴＨＥＳＯＵＴＨＣＨＩＮＡＳＥＡＭＯＮＳＯＯＮＥＸＰＥＲＩＭＥＮＴ（ＳＣＳＭＥＸ）ＣｈｅｎＬｏｎｇｘｕｎ（陈隆勋）ＤＲＡＦＴＰＲＯＰＯＳＡＬＦＯＲＴＨＥＳＯＵＴＨＣＨＩＮＡＳＥＡＭＯＮＳＯＯＮＥＸＰＥＲＩＭＥＮＴ（ＳＣ... 相似文献
8.
百余年的ENSO事件与北京汛期旱涝的统计关系 总被引：11，自引：0，他引：11
利用王绍武等人最近对近百年ＥＮＳＯ事件及强度的研究结果,对ＥＮＳＯ事件与北京汛期相当暴雨日数的统计关系进行分析,表明,ＥＮＳＯ事件与北京沁期旱涝存在较复杂的统计关系,ＥＮＳＯ事件的性质,强度,起始季节和持续时间长短等与汛期旱涝的对应关系是复杂的。根据１８６７－１９９８年的ＥＮＳＯ事件和同期北京汛期相当暴雨日数资料,给出一些统计结果。 相似文献
9.
《中国气象科学研究院年报》1995,(1)
ＭＯＮＴＨＬＹＡＮＤＳＥＡＳＯＮＡＬＯＰＥＲＡＴＩＯＮＡＬＮＵＭＥＲＩＣＡＬＷＥＡＴＨＥＲＰＲＥＤＩＣＴＩＯＮＩＮＴＨＥＳＵＭＭＥＲＯＦ１９９４ＳｏｎｇＱｉｎｇｌｉ（宋青丽）ａｎｄＺｈｅｎｇＱｉｎｇｌｉｎ（郑庆林）ＭＯＮＴＨＬＹＡＮＤＳＥＡＳＯＮＡＬ... 相似文献
10.
美国第20届气候诊断年会 总被引：1，自引：1，他引：1
文章介绍了１９９５年１０月在西雅图召开的美国第２０届气候诊断年会，着重讨论了如下８个问题：气候变暖，ＥＮＳＯ影响，全球降水分析，年代际气候变率，ＥＮＳＯ预测，数值气候预测，统计气候预报及气候模拟。 相似文献
11.
ENSO Events Recorded in the Guliya Ice Core 总被引：7，自引：0，他引：7
Based on the ENSO chronology and climatic information recovered from the Guliya ice core in the Tibetan Plateau, China, the ENSO teleconnection was investigated. The results showed that the negative precipitation anomalies are significantly associated with El Niño years but poorly with negative anomaly of 18O. Thus, the ice core records can be used as an archive of extremely global climate anomalies such as ENSO events. 相似文献
12.
13.
Lisa M. Baldini Frank McDermott James U. L. Baldini Matthew J. Fischer Martin Möllhoff 《Climate Dynamics》2010,35(6):977-993
This two-year study investigates the relative influence of meteorological variables (precipitation amount and temperature),
atmospheric circulation, air mass history, and moisture source region on Irish precipitation oxygen isotopes (δ18Op) on event and monthly timescales. Single predictor correlations reveal that on the event scale, 20% of δ18Op variability is attributable to the amount effect and 7% to the temperature effect while on the monthly timescale the North
Atlantic Oscillation accounts for up to 20% of δ18Op variability and the amount and temperature effects are not significant. In comparison, multivariate linear regression reveals
that the interaction of temperature and precipitation amount explains up to 40% of δ18Op variance at event and monthly timescales. Five-day kinematic back trajectories suggest that the amount-weighted mean δ18Op value of southerly- and northerly-derived events are lower by 2‰ relative to events derived from the west. Because air mass
history and atmospheric circulation appear to influence δ18Op in Ireland, Irish paleo-δ18Op proxy records are best interpreted as reflecting a combination of parameters, not just paleotemperature or paleorainfall. 相似文献
14.
Here we present a multi-proxy paleolimnological record from a closed-basin lake (Ebinur Lake) in northwestern China to investigate
climate change in this arid region during the last 1,500 years. The 120-cm long sediment core was dated by AMS radiocarbon
and 210Pb methods. The fine-grained clay sediments contain 3–17% organic matter (OM) and 9–31% carbonate, and are interrupted by
multiple sand and silt layers. These sand/silt layers, having consistently low OM, were found at 700–800, 1000–1100, 1300–1400,
and 1700–1750 a.d., with a time spacing of 300–400 years. We interpret that the low OM sand/silt layers were deposited during higher lake levels
caused by increased river inflow from the surrounding mountains during wet climate intervals. This interpretation is supported
by concurrent decreases in δ
18O and δ
13C of bulk carbonate and in carbonate content. Wet climate intervals at 700–800 a.d. and at 1700–1750 a.d. also correlate with elevated snow accumulation and low δ
18O from Guliya ice core on the NW Tibetan Plateau, both regions strongly influenced by the westerlies. This approximate 400-year
periodicity of wet–dry climate oscillations appear to correlate with solar activity as shown by atmosphere 14C concentration and with paleo-moisture records in interior North America. Our results suggest that solar activities might
have played a significant role in driving wet–dry climate oscillations at centennial scales in the interior of Eurasian continent. 相似文献
15.
Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ^18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ^18 O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the 51so in the rainy season smaller than inthe dry season. The δ^18 O sovalues in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ^18 O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ^18 O in precipitation reaches its minimum at Uriimqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ^18 O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ^18 O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ^18 O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season,but δ^18 O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ^18 O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ^18 O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon. 相似文献
16.
A. M. El-Asrag S. A. Al-Gamal A. Youssef D. M. Ahmed 《Theoretical and Applied Climatology》2003,74(3-4):191-202
Summary ?By analyzing normalized variables, it was found that the latitudinal secular variations of the rainwater deuterium fractionation
ratio δ2H, oxygen fractionation ratio δ18O, vapor pressure, and surface temperature were almost non-linear, occurred in parallel, and decreased with latitude. The
rate of depletion around the equator is asymmetric and smaller to the south of 45° S than to the north of 45° N. In the east
Mediterranean, the rate of change of δ18O with height was found to be −.2‰ per 100 m and that of δ2H is comparable with the dry lapse rate in the atmosphere.
Analysis of the annual time series of δ2H at Alexandria has indicated that variations show sinusoidal waveform with a major cycle of two years that accounts for 68%
of the total variance. Although the quasi-biannual cycle in the atmosphere has small amplitude in the lower layers of the
atmosphere at East Mediterranean latitudes, the major cycle in annual series of δ2H or δ18O may be linked to the quasi-biannual oscillation in the atmosphere.
It was also found that the first three Empirical Orthogonal Functions (EOF) account for 72% of the seasonal variation of δ2H and share 68% of the seasonal variation of δ18O. Share of variances of monthly EOF in the months of the year indicate that the main underlying factors that cause fractionation
processes for δ2H and δ18O are similar across the east Mediterranean especially in late winter and early spring.
Received May 13, 2002; revised July 8, 2002; accepted August 6, 2002 相似文献
17.
A stable oxygen, but not carbon, isotope chronology of Callitris columellaris reflects recent climate change in north-western Australia 总被引：1，自引：0，他引：1
We investigated the dendroclimatic potential of stable carbon (δ13C) and oxygen (δ18O) abundances in tree rings of Callitris columellaris F. Muell. Tree-ring chronologies were constructed from the central Pilbara, north-western Australia and span 1919–1999. Variation
in δ18O was more strongly related to climate than δ13C; ecological and physiological factors may have dampened the climate signal in the δ13C chronology. Tree-ring δ18O was most strongly correlated with relative humidity (RH) and rainfall (r = −0.36 and −0.39) of the wettest months of the summer period, January and February. The correlation with RH reflects its
effect on evaporative enrichment of leaf water. However, tree-ring δ18O may also partly reflect the variability in 18O signatures of rainfall, which are influenced by the amount of rainfall and atmospheric humidity. From the δ18O chronology, we inferred that from 1919 to 1955 summers were relatively dry and warm, but since 1955, summers in the Pilbara
region have become increasingly cooler and more humid. Since 1980, conditions have been the wettest and coolest of the last
80 years. These inferred changes in climate correspond to a measured increase in rainfall since 1980 in north-western Australia
associated with a greater intensity of tropical cyclones. We conclude that δ18O abundances in tree rings of C. columellaris have significant potential for reconstructing the climate of semi-arid Australia, a region for which observational climate
records are sparse. 相似文献
18.
Qinghai Lake, China, is located near the northern limit of the East Asian summer monsoon （EASM） and thus is an ideal region for studies of past monsoonal changes. However, isotope records from this region reflect the combined effects of multiple climatic factors, and make climatic interpretations difficult. The authors use multi-proxy records, generated from the same sediment core from Qinghai Lake, to disentangle these multiple effects in isotope records and to infer EASM variability during the late Holocene. Records of leaf wax （C2s） δD, lake carbonate 5180 and the Dunde ice core δ18O all indicate a millennial-scale depletion of mean isotopic values at -1500-1250 years before present. Compared with independent lake temperature and salinity records, the authors suggest that this depletion of long-term mean isotopic values must have resulted from changes in moisture sources in this region. In contrast, the authors attribute high-frequency （centennial timescale） C2s δD and ice core δ18O variability dominantly to a temperature effect. The multiproxy records provide a coherent picture in that many aspects of this regional climate （temperature, dryness, and moisture source） are strongly linked to the EASM variability. 相似文献
19.
O. A. Tarasova C. A. M. Brenninkmeijer S. S. Assonov N. F. Elansky T. Röckmann M. A. Sofiev 《Journal of Atmospheric Chemistry》2007,57(2):135-152
The concentration, radiocarbon (14C) and stable isotope (13C and 18O) content of CO have been determined in air samples collected across Russia (about 8,500 km) and along the Ob river during
the summer of 1999 to study the CO sources and sinks. An instrumented carriage on the Trans-Siberian railway and a boat on
the river Ob were used as atmospheric measurement platforms. In general, CO mixing ratios, CO stable isotope ratios, as well
as the abundances of 14CO over West Siberia were similar to those found at remote northern hemispheric baseline monitoring stations. Identified sources
of CO along the Ob appear to be connected to methane oxidation based on an inferred δ13Csource = −36.8 ± 0.6‰, while the value for δ18Osource = 9.0 ± 1.6‰ identifies it as burning. Thus flaring in the oil and gas production can be supposed to be a source. The extreme
13C depletion and concomitant 18O enrichment for two of the boat samples unambiguously indicates contamination by CO from combustion of natural gas (inferred
values δ13Csource = −40.3‰ and δ18Osource = 17.5‰). For these two samples, that have strongly elevated 14CO concentrations, the industrial area near Tomsk is identified as a source area using meteorological calculations. Along
the Trans-Siberian Railroad background CO was to various degrees contaminated with CO from methane combustion (δ13Csource = −35.7 ± 6.2‰ and δ18Osource = 10.3 ± 1.8‰). The impact of industrial burning was discernable in the vicinity of Perm-Kungur. 相似文献
20.
Humidity Effect and Its Influence on the Seasonal Distribution of Precipitation δ18O in Monsoon Regions 总被引：1，自引：1，他引：1
The humidity effect, namely the markedly positive correlation between the stable isotopic ratio in precipitation and the dew-point deficit △Td in the atmosphere, is put forward firstly and the relationships between the δ18O in precipitation and △Td are analyzed for the Urumqi and Kunming stations, which have completely different climatic characteristics. Although the seasonal variations in δ18O and △Td exhibit differences between the two stations, their humidity effect is notable. The correlation coefficient and its confidence level of the humidity effect are higher than those of the amount effect at Kunming, showing the marked influence of the humidity conditions in the atmosphere on stable isotopes in precipitation.Using a kinetic model for stable isotopic fractionation, and according to the seasonal distribution of meanmonthly temperature at 500 hPa at Kunming, the variations of the δ18O in condensate in cloud aresimulated. A very good agreement between the seasonal variations of the simulated mean δ18O and themean monthly temperature at 500 hPa is obtained, showing that the oxygen stable isotope in condensateof cloud experiences a temperature effect. Such a result is markedly different from the amount effect atthe ground. Based on the simulations of seasonal variations of δ18O in falling raindrops, it can be foundthat, in the dry season from November to April, the increasing trend with falling distance of δ18O in fallingraindrops corresponds remarkably to the great ATd, showing a strong evaporation enrichment function infalling raindrops; however, in the wet season from May to October, the δ18O in falling raindrops displaysan unapparent increase corresponding to the small ATd, except in May. By comparing the simulated meanδ18O at the ground with the actual monthly δ18O in precipitation, we see distinctly that the two monthlyδ18O variations agree very well. On average, the δ18O values are relatively lower because of the highlymoist air, heavy rainfall, small △Td and weak evaporation enrichment function of stable isotopes in thefalling raindrops, under the influence of vapor from the oceans; but they are relatively higher because of the dry air, light rainfall, great △Td and strong evaporation enrichment function in falling raindrops, under the control of the continental air mass. Therefore, the δ18O in precipitation at Kunming can be used to indicate the humidity situation in the atmosphere to a certain degree, and thus indicate the intensity of the precipitation and the strength of the monsoon indirectly. The humidity effect changes not only the magnitude of the stable isotopic ratio in precipitation but also its seasonal distribution due to its influence on the strength of the evaporation enrichment of stable isotopes in falling raindrops and the direction of the net mass transfer of stable isotopes between the atmosphere and the raindrops. Consequently, it is inferred that the humidity effect is probably one of the foremost causes generating the amount effect. 相似文献