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81.
Reconstruction of Conceptual Prediction Model for the Three Rainfall Patterns in the summer of eastern China under global warming 总被引:1,自引:0,他引:1
With the influence of global warming,the global climate has undergone significant inter-decadal variation since the late 1970s.Although El Nio-Southern Oscillation(ENSO)has been the strongest signal for predicting global climate inter-annual variability,its relation with the summer rainfall in China has significantly changed,and its indicative function on the summer rainfall in China has weakened.This has led to a significant decrease in the accuracy rate of early conceptual prediction models for the Three Rainfall Patterns in the summer of eastern China.On the basis of the difference analysis of atmospheric circulation system configuration in summer,as well as the interaction of ocean and atmospheric in previous winter between two phases,i.e.before and after the significant global warming(1951 to 1978 and 1979 to 2012,respectively),we concluded that(1)Under different inter-decadal backgrounds,the atmospheric circulations that impacted the Three Rainfall Patterns in the summer of eastern China showed consistency,but in the latter phase of the global warming,the Western Pacific Subtropical High(WPSH)was on the strong side,the position of which was in the south,and the blocking high in the Eurasia mid-high latitudes was active,while the polar vortex extended to the south,and meridional circulation intensified.This circulation background may have been conducive to the increase of the circulation frequency of Patterns II and III,and the decrease of the circulation frequency of Pattern I,thus leading to more Patterns II and III and fewer Pattern I in the summer rainfall of eastern China.(2)In the former phase,the corresponding previous winter SST fields of different rainfall patterns showed visible differences.The impact of ENSO on North Pacific Oscillation(NPO)was great,and the identification ability of which on Patterns I and II of summer rainfall was effective.In the latter phase,this identification ability decreased,while the impact of ENSO on the Pacific/North American(PNA)teleconnection pattern increased,and the identification ability of the PNA on Patterns II and III also increased.Based on the new inter-decadal climate background,this study reconstructs the conceptual prediction model for the Three Rainfall Patterns in summer of eastern China by using the previous winter PNA and the Eurasian(EU)teleconnection indexes.The fitting effect was satisfying,though it is necessary to be further tested. 相似文献
82.
温度变化是全球变化研究中非常重要的基础性问题,在中国近百年温度变化方面,十几年来已取得了明显进展,这首先表现在建立了若干条全国平均气温序列,而几条主要序列间的相关系数在0.73~0.97之间。同时,这些进展也表现在基础资料质量提高、空间覆盖面扩大、序列均一性改善以及结果可靠性提高等方面。对多序列进行综合分析得到的新结果显示,1906-2005年中国的年平均气温上升了(0.78±0.27)℃,2007年是我国近百年来最暖的一年;代表性分析显示,现有的几条中国温度序列中除覆盖完整的序列外,其他序列在1920或1930年代以前可能主要反映中国东部变化情况,但在此之后则能较好地代表全国大部分地区的气候变化特征。 相似文献
83.
绿柱石与硅铍石均为铍矿物家族中的主要成员,是重要的工业铍矿物,利用背散射和电子探针研究矿物特性时,常可见两者共生或发生交代的现象(饶灿,2009;Reyf, 2008; Evensen, 1999),其结晶条件对于成矿环境与成矿机制均具有重要的指示意义。前人已进行了关于绿柱石,硅铍石等铍矿物稳定性的实验研究,但研究多采用高温淬火的高温高压实验装置,误差大,且无法原位观测矿物结晶习性(王振杰, 1992;Sirbescu et al., 2009),本文利用热液金刚石压腔,原位观测了绿柱石与硅铍石的结晶过程,得到了它们结晶的温压条件及结晶习性。 相似文献
84.
Jacek?MajorowiczEmail author Jan??afanda Rajmund?Przybylak Gabriel?Wójcik 《Pure and Applied Geophysics》2004,161(2):351-363
Ground Surface Temperature (GST) history in Poland was derived from the inversion of temperature-depth profiles in over 20 wells. Temperature histories for the period 1500 A.D. through 1977 A.D. agree well with the instrumental record of the surface-air temperature available for the last two centuries. A statistical correlation of the reconstructed histories (from the well temperature data) with the instrumental record (air temperature) from the homogeneous Warsaw series is high (>0.8). Functional space inversion (FSI) of the temperature data with depth shows that beginning in the early 19th century, temperatures warmed by 0.9 ± 0.1°C following a long period of colder climate before. The last number could be a minimal as higher warming was calculated using a simple model based on surface temperature for the observational period (homogenized Warsaw surface temperature series, Lorenc, 2000) and POM (pre-observational mean; Harris and Chapman, 1998) of –1.53oC below the 1951–1980 mean temperature level. 相似文献
85.
Studies on the coral reefs of the South China Sea (SCS) was the theme of the 6th Session of the 3rd Conference on Earth System Science (CESS) in Shanghai, 2014. This session discussed the most recent study developments on the SCS coral reefs, including coral reefs’ responses to global changes, coral reefs’ records on past climatic variations, and the activities about constructions and oil gas explorations in the coral reefs areas of the SCS. Disturbed by intensive anthropogenic activities and global climate warming, coral reefs in the SCS have declined dramatically, reflecting the up to 80% decrease of living coral cover and many areas having less than 20% of living coral cover. Geochemical data of SCS coral skeletons clearly show that since the Industry Revolution, the pollution situation of the SCS have dramatically increased and the seawater pH values have been continuously lowering, i.e. oceanic acidification. All these environmental phenomenon are further stressing the healthy development of the coral reef ecosystem in the SCS. Meanwhile, the poor coral reef ecosystems in the SCS are facing more anthropogenic disturbances such as coastal developments and engineering constructions. Obviously, the SCS coral reefs will be faced with more environmental challenges in the coming future. We therefore suggest that the policy makers should realize the extreme importance and the fragile of the coral reef ecosystems, and scientifically and with great cautions design construction project when in coral reef areas. We initiated the concept of “green engineering” for future developments in coral reef areas. Coral reefs are widely spreading in the whole SCS, and most of them developed since Miocene. Variations in coral reef structures provide good future oil-gas exploration. Because the SCS coral reefs have a long-developing history and a wide spatial distribution, they provide great potential in recording past environmental changes. 相似文献
86.
The impact of global warming on the warmest and coldest days of the annual cycle is explored according to an A2 scenario simulated
by the CNRM-CM3 climate model in the framework of the IPCC AR4 intercomparison. Given the multi-model spread in IPCC projections,
a validation strategy is proposed using the NCEP/NCAR reanalysis. Validation of the late twentieth century model climatology
shows that warm and cold model events are slightly too long and infrequent. Although interannual trends in the warm (cold)
day occurrence were positive (negative) only for six (three) of the nine considered sub-continental regions, simulated model
trends are always positive (negative). This different behaviour suggests that simulated non-anthropogenic decadal variability
is small relative to anthropogenic trends. Large-scale synoptic processes associated with European regional warm and cold
peaks are also described and validated. Regional cold peaks are better reproduced than warm peaks, whose intensity accuracy
is limited by other physical variables. Positive (negative) winter anomalies of sea and land surface temperature lead to summers
with severe (weak) temperatures. These inter-annual anomalies are generated by a persistent pressure dipole over Europe. Regarding
climate change, warm (cold) events will become more (less) frequent and longer (shorter). The number of warm days will largely
rise and the number of cold days will dramatically decrease. The intensity of warm days will be particularly pronounced over
Europe, given the projected summer drying in this region. However, according to the limited skill of the CNRM model, these
results must be considered with caution. 相似文献
87.
棉铃虫Helicoverpa armigera 属鳞翅目夜蛾科,是一种世界性的重大害虫,在世界各地均有分布。因其具有远距离迁飞,繁殖力强等特点,条件适宜时常大面积暴发成灾,给农业生产带来较大损失。摸清棉铃虫生活习性、种群变化规律是棉铃虫防治的前提条件。由于棉铃虫是变温昆虫,气候条件对其生长发育、成灾机制等产生极大影响。因此,本文系统综述了气候变暖对棉铃虫影响的研究进展,包括棉铃虫生长发育、体色变化、繁殖、滞育、飞行、越冬、与作物的互作关系等方面,并对未来研究重点进行了展望。以期对棉铃虫的综合治理提供理论依据。 相似文献
88.
Study of temperature and precipitation variations in Italy based on surface instrumental observations 总被引:1,自引:0,他引:1
Tiziano Colombo Vinicio Pelino Stefania Vergari Paolo Cristofanelli Paolo Bonasoni 《Global and Planetary Change》2007,57(3-4):308-318
In this paper we present a study concerning the climatic behaviour of two principal observables, temperature and precipitation as obtained from the measurements carried out at 50 Italian meteorological stations, since 1961. Analyses of WMO Climate Normals (CliNo) from 1961 to 1990 have been performed dividing the 50 Italian stations in three different classes: mountain (11 stations), continental (17) and coastal areas (21).The comparison of the CliNo 1961–1990 with the trend of temperature and precipitation for the period 1991–2000 showed a sharp significant increase of summer temperatures over Italy starting from 1980. This phenomenon was particularly evident for mountain stations, where a significant temperature increase has been recorded also during the autumn. Moreover, the analysis of precipitation data permitted to point out that, starting from 1980, mountain stations have been affected by a significant increase of precipitation events during autumn and winter, while for the rest of the Italian territory a reduction of precipitations has been recorded during early spring. 相似文献
89.
历次核试验进入海洋的~(137)Cs对中国近海影响的模拟研究 总被引:1,自引:0,他引:1
1945年以来,世界各主要核国家进行了数千次核试验,这些核试验产生的绝大部分放射性物质通过多种途径进入海洋,对海洋环境造成放射性污染。本文建立了一个准全球海洋的放射性物质输运和扩散数值模式,通过数值模拟手段评估了历史核试验释放的放射性物质137 Cs对中国近海海洋环境的影响。本文借助前人工作评估了核试验释放137Cs进入海洋的途径和总量;通过比较模拟结果与观测资料,表明本文建立的放射性物质模式能够较好地模拟出137Cs在中国近海及其邻近海域的分布情况和随时间演变特征;模拟结果表明中国近海里的137Cs浓度在20世纪50年代中期达到最大,其中吕宋海峡海域137Cs浓度最高,达80.99Bq/m3;进一步分析了2011年3月份日本福岛核事故前中国近海137Cs浓度分布状况,2011年整个中国近海137Cs浓度介于1.0~1.6Bq/m3间,且其浓度垂向分布较均匀,相对封闭的南海浓度略高于其他海域。 相似文献
90.
论气候变暖背景下干旱和干旱灾害风险特征与管理策略简 总被引:2,自引:0,他引:2
The drought is a most severe natural disaster worldwide, which leads to great risk in human being. The drought disaster and risk have more prominent because of obvious climatic warming in the last hundred years. At present, the understanding of the internal laws of the occurrence of drought and drought risk is not comprehensive, and the recognition of the characteristics of the drought and drought risk under climatic warming is obscure. In this paper, we summarized systematically the domestic and overseas research progress of the drought and drought disaster risk, introduced the principle of the drought disaster transfer process and the essential features of drought disaster, analyzed synthetically the main characteristics and interactions among the key factors of the drought disaster risk, discussed the effect of climatic warming on drought and drought disaster risk, and probed into the basic requirement of drought disaster risk management. Above all, we provide the main protective measurements of the drought disaster and the main strategy of drought disaster risk management. 相似文献