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Impacts of the stratospheric quasi-biennial oscillation on the tropospheric circulation and climate in the Northeast Asia-North Pacific region in early summer
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作者 Xiang Gao Jinggao Hu +1 位作者 Rongcai Ren Yifan Shen 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第3期14-19,共6页
本文研究了平流层准两年振荡(QBO)对东北亚-北太平洋地区初夏对流层环流和地表气温的影响.在QBO西风位相年,东北亚至北太平洋地区存在一支由QBO引发的平均经向环流异常,该经向环流异常可在东北亚至北太平洋地区激发正涡度,并形成异常气... 本文研究了平流层准两年振荡(QBO)对东北亚-北太平洋地区初夏对流层环流和地表气温的影响.在QBO西风位相年,东北亚至北太平洋地区存在一支由QBO引发的平均经向环流异常,该经向环流异常可在东北亚至北太平洋地区激发正涡度,并形成异常气旋式环流.气旋左侧出现的异常偏北风导致6月东北亚地表气温下降.QBO东风位相年的结果与西风位相年大致相反.这些结果为QBO对热带外地区天气,气候的影响提供了新的证据,并为东北亚初夏地表气温的预测提供了新的线索。 展开更多
关键词 平流层准两年振荡 平均经向环流 初夏时期 地表气温 热带外对流层
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ADVANCE IN STUDIES OF TROPOSPHERIC BIENNIAL OSCILLATION
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作者 郑彬 梁建茵 《Journal of Tropical Meteorology》 SCIE 2005年第1期1-9,共9页
There are obvious biennial phenomena of circulation, meteorological and climatic elements in the troposphere, named as Tropospheric (Quasi-) Biennial Oscillation (TBO). Many phenomena of TBO are discovered, such as va... There are obvious biennial phenomena of circulation, meteorological and climatic elements in the troposphere, named as Tropospheric (Quasi-) Biennial Oscillation (TBO). Many phenomena of TBO are discovered, such as variations of TBO in tropospheric temperature, pressure, winds field, monsoon and subtropical high etc. The mechanism of TBO is explored and the results demonstrate that tropical ocean (the Indian Ocean and the Pacific Ocean, mainly) and Stratospheric QBO play important roles in the TBO. In addition, Eurasian snow cover and solar activity of 11yr period can affect TBO very possibly. 展开更多
关键词 tropospheric biennial oscillation (TBO) tropical ocean quasi-biennial oscillation (QBO)
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The Features of Ozone Quasi-Biennial Oscillation in Tropical Stratosphere and Its Numerical Simulation 被引量:4
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作者 陈月娟 郑彬 张弘 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第5期777-793,共17页
The inlcrunnual variation of the vertical distribution of ozone in the tropical stratosphere and its quasi—biennial oscillation (QBO) is analyzed using HALOE data. The results are compared with the wind QBO. A numeri... The inlcrunnual variation of the vertical distribution of ozone in the tropical stratosphere and its quasi—biennial oscillation (QBO) is analyzed using HALOE data. The results are compared with the wind QBO. A numerical experiment is carried out to study the effects of wind QBO on the distribution, and variation of ozone in the stratosphere by using (he NCAR interactive chemical, dynamical, and radiative two—dimensional model (SOCRATES). Data analysis shows that the location of the maximum ozone mixing ratio in the stratosphere changes in the meridional and vertical directions, and assumes a quasi—biennial period. The meridional and vertical motion of the maximum mixing ratio leads to a QBO of column ozone and its hemispheric asymmetry. The QBO of the location of the maximum is closely connected with the zonal wind QBO. The data analysis also shows that in the tropical region, the phase of the QBO for ozone density changes many times with height. Numerical simulation shows that the meridional circulation induced by the wind QBO includes three pairs of cells in the stratosphere, which have hemispheric symmetry. The transport of ozone by the induced meridional circulation in various latitudes and heights is the main dynamic cause for the ozone QBO. Cells of the induced circulation in the middle stratosphere (25-35 km) play an important role in producing the ozone QBO. 展开更多
关键词 ozone quasi—biennial oscillation (QBO) HALOE data NCAR model numerical simulation SOCRATES
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Spatial Patterns of Tropospheric Biennial Oscillation and Its Numerical Simulation 被引量:4
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作者 郑彬 谷德军 +1 位作者 林爱兰 李春晖 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第5期815-823,共9页
In order to investigate the spatial patterns of the Tropospheric Biennial Oscillation (TBO) on the global scale, the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) monthly averaged preci... In order to investigate the spatial patterns of the Tropospheric Biennial Oscillation (TBO) on the global scale, the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) monthly averaged precipitation and the Climate Diagnostics Center (CDC) monthly outgoing long-wave radiation (OLR) and SST are used in conjunction with TBO bandpass-filtering. The results indicate active biennial variability in the tropical eastern-central Pacific regions. It is evident that observations reflect the biennial component of the ENSO rather than the TBO itself. Since some studies have pointed out that the TBO is a broad-scale phenomenon differing from the ENSO, to investigate the pure TBO the ENSO signal must be excluded. The Scale Interaction Experiment-FRCGC (SINTEX-F) coupled general circulation model (CGCM) developed at Japan Frontier Research Center for Global Change (FRCGC) can capture both the ENSO and the biennial signals. Air-sea interactions in the tropical eastern-central Pacific are decoupled to eliminate the effects of ENSO in a experiment by SINTEX-F and the results show that biennial variability still exists even without ENSO. It seems to mean that the TBO and ENSO are independent from each other. Furthermore, the model results indicate that the two key regions are southwest Sumatra and the tropical western Pacific for the TBO cycle. 展开更多
关键词 tropospheric biennial oscillation air-sea interaction spatial pattern
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Effects of South China Sea/western North Pacific summer monsoon on tropospheric biennial oscillation (TBO) 被引量:3
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作者 郑彬 谷德军 +1 位作者 林爱兰 李春晖 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1472-1476,共5页
Several theories have been developed to explain tropical biennial oscillation (TBO), as an air-sea interactive system to impact Asian and global weather and climate, and some models have been established to produce ... Several theories have been developed to explain tropical biennial oscillation (TBO), as an air-sea interactive system to impact Asian and global weather and climate, and some models have been established to produce a TBO. A simple 5-box model, with almost all the key processes associated with TBO, can produce a TBO by including airsea interactions in the monsoon regions. Despite that, the South China Sea/western North Pacific summer monsoon (SCS/WNPSM), a very important monsoon subsystem, is neglected. In this paper, based on the dynamical framework of 5-box model, the term of SCS/WNPSM has been added and a 6-box model has been developed. Comparing the difference of TBO sensibilities with several key parameters, air-sea coupling coefficient α, SST-thermocline feedback coefficient γand wind-evaporation feedback coefficient λ, between the modified model and original model, TBO is more sensible to the parameters in the new model. The results imply that the eastern Pacific and local wind-evaporation play more important roles in the TBO when including SCS /WNPSM. 展开更多
关键词 South China Sea western North Pacific summer monsoon tropospheric biennial oscillation
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HCl Quasi-Biennial Oscillation in the Stratosphere and a Comparison with Ozone QBO 被引量:7
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作者 陈月娟 施春华 郑彬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第5期751-758,共8页
HALOE data from 1992 to 2003 are used to analyze the interannual variation of the HCl volume mixing ratio and its quasi-biennial oscillation (QBO) in the stratosphere, and the results are compared with the ozone QBO... HALOE data from 1992 to 2003 are used to analyze the interannual variation of the HCl volume mixing ratio and its quasi-biennial oscillation (QBO) in the stratosphere, and the results are compared with the ozone QBO. Then, the NCAR two-dimensional interactive chemical, dynamical and radiative model is used to study the effects of the wind QBO on the distribution and variation of HCl in the stratosphere. The results show that the QBO signals in the HCl mixing ratio are mainly at altitudes from 50 hPa to 5 hPa; the larger amplitudes are located between 30 hPa and 10 hPa; a higher HCl mixing ratio usually corresponds to the westerly phase of the wind QBO and a lower HCl mixing ratio usually corresponds to the easterly phase of the wind QBO in a level near 20 hPa and below. In the layer near 10 hPa-5 hPa, the phase of the HCl QBO reverses earlier than the phase of the wind QBO; the QBO signals for HCl in the extratropics are also clear, but with reversed phase compared with those over the Tropics. The HCl QBO signals at 30°N are clearer than those at 30°S; the QBOs for HCl and ozone have a similar phase at the 50 hPa-20 hPa level while they are out of phase near 10 hPa; the simulated structures of the HCl QBO agree well with observations. The mechanism for the formation of the HCl QBO and the reason for differences in the vertical structure of the HCl and ozone QBO are attributed to the transport of HCl and ozone by the wind QBO-induced meridional circulation. 展开更多
关键词 HCL quasi-biennial oscillation STRATOSPHERE
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Teleconnections of Inter-Annual Streamflow Fluctuation in Slovakia with Arctic Oscillation,North Atlantic Oscillation,Southern Oscillation,and Quasi-Biennial Oscillation Phenomena 被引量:8
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作者 Pavla PEKAROVA Jan PEKAR 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期655-663,共9页
The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation (QBO), Southern Oscillation (SO), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO) phenomena with longter... The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation (QBO), Southern Oscillation (SO), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO) phenomena with longterm streamflow fluctuation of the Bela River (1895-2004) and Cierny Hron River (1931-2004) (central Slovakia). Homogeneity, long-term trends, as well as inter-annual dry and wet cycles were analyzed for the entire 1895-2004 time series of the Bela River and for the 1931-2004 time series of the Cierny Hron River. Inter-annual fluctuation of the wet and dry periods was identified using spectral analysis. The most significant period is that of 3.6 years. Other significant periods are those of 2.35 years, 13.5 years, and 21 years. Since these periods were found in other rivers of the world, as well as in SO, NAO, and AO phenomena, they can be considered as relating to the general regularity of the Earth. 展开更多
关键词 inter-annual discharge fluctuation spectral analysis TELECONNECTION Quasi-biennial Oscillation Southern Oscillation North Atlantic Oscillation Arctic Oscillation
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Interdecadal variability of the tropospheric biennial oscillation in the western North Pacific 被引量:2
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作者 郑彬 林爱兰 +1 位作者 谷德军 李春晖 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1935-1938,共4页
The observed tropospheric biennial oscillation (TBO) in the western North Pacific (WNP) monsoon region has an interdecadal variability with a period of 40-50 yr. That suggests a weaker effect of the TBO on the Eas... The observed tropospheric biennial oscillation (TBO) in the western North Pacific (WNP) monsoon region has an interdecadal variability with a period of 40-50 yr. That suggests a weaker effect of the TBO on the East Asia followed by a stronger one. A simple analytic model was designed to investigate the mechanism of the interdecadal variability of the TBO. The results indicated that a local TBO air-sea system not only supports the TBO variability in the WNP monsoon region but also produces an interdecadal variability of the TBO. 展开更多
关键词 tropospheric biennial oscillation western North Pacific interdecadal variability air-sea interaction
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Contrasting the Indian and western North Pacific summer monsoons in terms of their intensity of interannual variability and biennial relationship with ENSO 被引量:3
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作者 CHEN Baiyang WANG Lei WU Minmin 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第5期462-469,共8页
The intensity of interannual variability(IIV)of the monsoon and monsoon–ENSO biennial relationship(MEBR)were examined and compared for both the Indian summer monsoon(ISM)and western North Pacific summer monsoon(WNPSM... The intensity of interannual variability(IIV)of the monsoon and monsoon–ENSO biennial relationship(MEBR)were examined and compared for both the Indian summer monsoon(ISM)and western North Pacific summer monsoon(WNPSM)during 1958–2018.Covariability of the IIV and MEBR were identified for the two monsoons.When the MEBR was strong(weak),the IIV of the monsoon was observed to be large(small).This rule applied to both the ISM and WNPSM.Out-ofphase relationships were found between the ISM and the WNPSM.When the IIV and MEBR of the ISM were strong(weak),those of the WNPSM tended to be weak(strong).During the period with a stronger(weaker)ENSO–Atlantic coupling after(before)the mid-1980 s,the IIV and MEBR of the WNPSM(ISM)were observed to be stronger.The increasing influences from the tropical Atlantic sea surface temperature(SST)may trigger the observed seesaw pattern of the ISM and WNPSM in terms of the IIV and MEBR multidecadal variability.The results imply that tropical Atlantic SST may need to be given more attention and consideration when predicting future monsoon variability of the ISM and WNPSM. 展开更多
关键词 Indian summer monsoon western North Pacific summer monsoon ENSO intensity of interannual variability monsoon–ENSO biennial relationship
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Air-sea interactions associated with tropospheric biennial oscillation in South China Sea summer monsoon and their effects on El Nio-Southern Oscillation 被引量:1
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作者 ZHENG Bin LU Feng WEI Hongcheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第6期6-12,共7页
The South China Sea summer monsoon (SCSSM) behaves with prominent climate variability from the in- traseasonal to interdecadal time scales. On the interannual time scale, the biennial variability (so-called troposp... The South China Sea summer monsoon (SCSSM) behaves with prominent climate variability from the in- traseasonal to interdecadal time scales. On the interannual time scale, the biennial variability (so-called tropospheric biennial oscillation, TBO) is as important as the E1 Nifio-Southem Oscillation (ENSO) period. Some observed data sets, including reanalysis data, are used to explore the associated air-sea interactive physical processes and how the SCSSM TBO affects the ENSO. The results show that the shearing vorticity induced by the north Indian Ocean sea surface temperature anomalies (SSTAs) and the anomalous Philip- pine Sea anticyclone both contribute to the TBO in the SCSSM. The results also indicate that the ENSO has a weak effect on the SCSSM TBO, whereas the latter affects the ENSO to some extent. 展开更多
关键词 South China Sea MONSOON tropospheric biennial oscillation El Nifio-Southern Oscillation
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Weakening of the biennial relationship between Central American and equatorial South American rainfall in recent decades 被引量:1
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作者 WANG Lei WU Min-Min 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第6期427-434,共8页
There is a rainfall variability biennial relationship between Central America (CA) and equatorial South America (ESA) over the tropical western hemisphere, which is known to have arisen due to the combined effects... There is a rainfall variability biennial relationship between Central America (CA) and equatorial South America (ESA) over the tropical western hemisphere, which is known to have arisen due to the combined effects of ENSO and tropical North Atlantic (TNA) SST. Here, the authors report that this biennial rainfall relationship between CA and ESA has weakened remarkably since 2000, with weakening in both in-phase and out-of-phase rainfall transitions. The observed decadal changes in the biennial relationship between CA and ESA rainfall can be attributed to changes in the effects of ENSO and TNA SST since 2000, which may be associated with more frequent occurrences of the central Pacific or'Modoki' type El Ni^o. The weakening of the association with ENSO for CA rainfall since 2000 might have given rise to the weakening of the in-phase rain transition from CA rainfall to the following ESA rainfall. The weakened linkage between boreal-winter ESA rainfall and the subsequent boreal-summer TNA SST since 2000 may have resulted in the weakening of the out- of-phase rainfall transition from boreal-winter ESA rainfall to the subsequent boreal-summer CA rainfall. 展开更多
关键词 biennial variability tropicalrainfall ENSO tropicalNorth Atlantic twenty-firstcentury climate shift CentraAmerica equatorial SouthAmerica
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Allelopathic potential of <i>Artemisia biennis</i>(biennial wormwood)
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作者 George O. Kegode Mark G. Ciernia David B. Vlieger 《Agricultural Sciences》 2012年第4期582-587,共6页
In this study, Artemisia biennis was seeded in a greenhouse and raised to an average plant height of 100 cm. Aboveground plant portions were harvested and partitioned into leaves and stems, and dried;while roots were ... In this study, Artemisia biennis was seeded in a greenhouse and raised to an average plant height of 100 cm. Aboveground plant portions were harvested and partitioned into leaves and stems, and dried;while roots were either removed from some soil (soil – roots) or left in soil (soil + roots). Greenhouse studies were conducted to evaluate the allelopathic potential of A. biennis leaves, roots, and stems;and soil – roots, and soil + roots on Solanum melanocerasum plant height and fresh weight plant–1. When 5 g of root and stem biomass were added to soil, S. melanocerasum plant height and fresh weight plant–1 was reduced by 75 and 88%, respectively. In contrast, 5 g of leaf biomass caused an increase in S. melanocerasum plant height and fresh weight plant–1 by 35% and 43%, respectively;whereas, 20 g of leaf biomass depressed both variables by 50% and 65%, also respectively. Plant height was more suppressed when S. melanocerasum grew in soil – roots as opposed to soil + roots, whereas fresh weight plant–1 was similar between soil treatments. S. melanocerasum plant height was reduced by 70 and 55% when grown in soil – roots and soil + roots, respectively. In contrast, S. melanocerasum fresh weight plant–1 was reduced by 76% in both soil treatments. The reduction in S. melanocerasum plant attributes in this study is indicative of the allelopathic potential of A. biennis. Furthermore, A. biennis allelopathy is differenttially expressed among plant parts, primarily in roots. This may explain how A. biennis is capable of dominating a habitat once it becomes established. The presence of extractable compounds with herbicidal activity could increase the potential usefulness of A. biennis. 展开更多
关键词 Allelopathic POTENTIAL ARTEMISIA Biennis biennial Wormwood GARDEN Huckleberry SOLANUM Melanocerasum
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Do Circulating RSV-Genotypes Affect Established Biennial Epidemic Periodicity in Zagreb Region?
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作者 Gordana Mlinaric-Galinovic Dubravko Forcic +3 位作者 Jelena Ivancic-Jelecki Gordana Vojnovic Jadranka Bozikov Robert C. Welliver 《Open Journal of Respiratory Diseases》 2012年第4期91-94,共4页
Objective: The biennial epidemic pattern of respiratory syncytial virus (RSV) circulation in Croatia has been preserved and could not be related to climatic factors and the predominant RSV subtypes. The possibility th... Objective: The biennial epidemic pattern of respiratory syncytial virus (RSV) circulation in Croatia has been preserved and could not be related to climatic factors and the predominant RSV subtypes. The possibility that the circulation of different RSV genotypes affect the outbreak cycle in children in Croatia (Zagreb region) over a period of 3 consecutive years was explored in the paper. Methods: The study group consisted of inpatients, aged 0-10 years, who were hospi- talized with acute respiratory tract infections caused by RSV, in Zagreb, over the period from 1 January 2006 to 31 De- cember 2008. The virus was identified in the nasopharyngeal secretion using direct immunofluorescence method. The virus subtype and genotype was determined by real-time PCR and sequence analysis, respectively. Results: RSV infec- tions identified in 731 children. RSV subtype A caused 399 infections, and subtype B 332. Two subtype A genotypes (NA1 and GA5) and three subtype B genotypes (BA7, BA9 and BA10) were found. During persistent RSV biennial cycles namely four succeeding outbreaks, the new genotype from the previous smaller outbreak persevered into the up- coming larger outbreak. Conclusion: Our molecular-epidemiology study of RSV subtypes and genotypes during calen- dar months demonstrates that the biennial RSV cycle cannot be fully explained by the dynamic of the predominant cir- culating genotype of RSV. Other unknown factors account for the biennial cycle of RSV epidemics in Croatia.). 展开更多
关键词 biennial Cycle RESPIRATORY Syncytial Virus Types A and B GENOTYPES
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Quasi-Biennial Oscillations in Atmospheric Ozone from the Chemistry-Climate Model and Ozone Reanalysis
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作者 Vazhathottathil Madhu Kengo Sudo 《American Journal of Climate Change》 2019年第1期110-136,共27页
The quasi-biennial oscillation is the primary mode of variability of the equatorial mean zonal wind in the lower stratosphere, which is characterized by downward propagating easterly and westerly wind regimes from 10 ... The quasi-biennial oscillation is the primary mode of variability of the equatorial mean zonal wind in the lower stratosphere, which is characterized by downward propagating easterly and westerly wind regimes from 10 hPa level with a period approximately 28 months. The effects of the stratospheric quasi-biennial oscillation in zonal winds (SQBO) are not only confined to atmospheric dynamics but also seen in the chemical constituent (trace gases) anomalies such as ozone, water vapor, carbon monoxide and methane in the lower stratosphere. In this study, we examined the SQBO and associated ozone quasi-biennial oscillation (OQBO) using the chemistry-climate model CHASER (MIROC-ESM) simulations and ECMWF ERA-Interim ozone reanalysis for the period 2000-2015. We used lower stratospheric zonal wind from the radiosonde observations and total column ozone (TCO) from Aura Satellite (OMI Instruments) over Singapore to compare the SQBO and OQBO phases with model and reanalysis. The SQBO shows large variations in magnitude and periodicity during the period of study and the amplitude of OQBO also changes in accordance with the westerly (+ve ozone anomaly) and easterly (-ve ozone anomaly) phases of SQBO. During the Westerly phase of Ozone QBO (WQBO) corresponds to average positive total ozone anomaly of &#126;10 DU and in the Easterly phase of Ozone QBO (EQBO) corresponds to an average negative total ozone anomaly &#126;&#8722;10 DU in the tropical lower stratosphere. Since the SQBO phases were explained by the vertical propagations of Mixed-Ross by Gravity (MRG) waves and Kelvin waves, the correlation of ozone volume mixing ratio with zonal and vertical velocities gives quasi-biennial signals, which indicate the OQBO mechanism more related to dynamical transport than the stratospheric photochemical variations. Since the average amplitude of OQBO phases gives &#126;+/&#8722;10 DU from the observations during easterly and westerly phases SQBO, we need more research focused on the dynamical transport than the photochemical changes to understand the tropical ozone variability due to the ozone quasi-biennial oscillations. 展开更多
关键词 OZONE Layer EQUATORIAL PLANETARY WAVES Quasi-biennial OSCILLATIONS
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Eco-economic research and construction of harmonious society in China:a survey of the 7^(th)Biennial Conference of Chinese Ecological Economics Society,2006
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作者 Zeng Shaolun 《Ecological Economy》 2007年第1期106-110,共5页
The 7th Biennial Conference of Chinese Ecological Economics Society (CEES) was held from 5th to 7th, Nov.2006 in Qingdao University. The paper summarizes the major viewpoint presented at the conference: eco-economicre... The 7th Biennial Conference of Chinese Ecological Economics Society (CEES) was held from 5th to 7th, Nov.2006 in Qingdao University. The paper summarizes the major viewpoint presented at the conference: eco-economicresearch and construction of a harmonious society in China. The conference put forward that it is an objectivity andinevitability for human being to enter the harmonious society, that eco-economics is one of the theoretical bases for theconstruction of the harmonious society, and that the research of eco-economics in China should reflect new contentsdeveloped in the process of modernization in China and make proper contributions to the construction of the harmonioussociety. 展开更多
关键词 CEES biennial Conference 2006 Survey Harmonious society Eco-economic research
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生产要素、FDI、环境消耗与中国经济增长源泉——基于Biennial Malmquist生产率指数的分解 被引量:3
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作者 唐李伟 胡宗义 《系统工程理论与实践》 EI CSSCI CSCD 北大核心 2016年第3期581-592,共12页
论文将资本存量区分为国内资本存量和国外资本存量,基于Biennial Malmquist生产率指数对考虑环境消耗的中国1998—2011年间的经济增长源泉进行分解.测算结果显示,整体来看,全要素生产率、劳动投入、国内资本、国外资本以及环境消耗对经... 论文将资本存量区分为国内资本存量和国外资本存量,基于Biennial Malmquist生产率指数对考虑环境消耗的中国1998—2011年间的经济增长源泉进行分解.测算结果显示,整体来看,全要素生产率、劳动投入、国内资本、国外资本以及环境消耗对经济增长的贡献率分别为4.33%、3.67%、48.1%、18%和25.9%.分地区统计发现,东部地区全要素生产率对经济增长的贡献率显著大于中西部地区,中部地区的经济增长对资本的依赖性最大,西部地区经济增长对国外资本的依赖性最大.当前中国经济增长对资本依赖度较大且存在地区差异,全要素生产率对经济增长的贡献率有限,经济在快速增长的同时,对环境产生了巨大消耗,这种经济增长模式是不可持续的,转变经济增长方式是必然选择. 展开更多
关键词 生产要素 国外资本 环境消耗 biennial MALMQUIST生产率指数 经济增长源泉
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Dynamical mechanism of the stratospheric quasibiennial oscillation impact on the South China Sea Summer Monsoon 被引量:7
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作者 ZHENG Bin GU DeJun +1 位作者 LIN AiLan LI ChunHui 《Science China Earth Sciences》 SCIE EI CAS 2007年第9期1424-1432,共9页
The National Center for the Atmospheric Research(NCAR)middle atmospheric model is used to study the effects of the quasi-biennial oscillation in the stratosphere(QBO)on the tropopause and uppe troposphere,and the rela... The National Center for the Atmospheric Research(NCAR)middle atmospheric model is used to study the effects of the quasi-biennial oscillation in the stratosphere(QBO)on the tropopause and uppe troposphere,and the relationship between the QBO and South China Sea Summer Monsoon SCSSM is explored through NCEP(the National Centers for Environmental Prediction)/NCAR,ECMWF(Euro pean Centre for Medium-Range Weather Forecasts)monthly mean wind data and in situ sounding data The simulations show that the QBO-induced residual circulations propagate downwards,and affect the tropopause and upper troposphere during the periods of mid-late QBO phase and phase transition Meanwhile,diagnostic analyses indicate that anomalous circulation similar to SCSSM circulation is generated to strengthen the SCSSM during the easterly phase and anomalous Hadley-like circulation weakens the SCSSM during the westerly.Though the QBO has effects on the SCSSM by meridiona circulation,it is not a sole mechanism on the SCSSM TBO mode. 展开更多
关键词 stratospheric quasi-biennial oscillation South China Sea Summer Monsoon tropospheric biennial oscillation
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沙枣2年生植株表型多样性分析与观赏性综合评价
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作者 王梓煦 曾郅涵 +2 位作者 王秀军 李子航 李庆卫 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第8期36-48,共13页
【目的】在园林绿化苗木生产过程中,更早筛选出具有高观赏价值、适合在北方地区推广种植的优良植株,是实现沙枣良种选育的关键。【方法】对106份沙枣Elaeagnus angustifolia 2年生幼苗为试验材料的表型性状、生长情况进行连续2年的观察... 【目的】在园林绿化苗木生产过程中,更早筛选出具有高观赏价值、适合在北方地区推广种植的优良植株,是实现沙枣良种选育的关键。【方法】对106份沙枣Elaeagnus angustifolia 2年生幼苗为试验材料的表型性状、生长情况进行连续2年的观察记录,同时进行相关性分析、主成分分析和聚类分析探究其表型性状的多样性和观赏特性。【结果】结果表明:1)106份沙枣植株具有丰富的表型变异性,地径年生长量的变异系数最大,为57.56%,分枝角度的多样性指数最高,为2.0232;2)相关性分析表明,株高年生长量与地径年生长量存在极显著正相关(P<0.01),叶长与株高、地径年生长量呈显著正相关(P<0.05);主成分分析表明,前4个主成分累计贡献率达74.449%,其中叶片大小,苗木生长势相关性状指标影响较大;3)供试的106份沙枣幼苗可通过聚类分析划分为4大类群,其中第Ⅰ类群的种质主要特征为叶片小,生长速度缓慢;第Ⅱ类群的种质主要特征为叶片狭长,叶表颜色偏深灰绿,生长势居中;第Ⅲ类群的种质主要特征为叶片大且偏卵圆形、树冠峭立、叶色鲜亮,生长势居中;第Ⅳ类群的种质主要特征为叶片大,树冠张开,生长速度极快。4)采用层次分析法综合分析发现,叶色、株形等8个性状可作为沙枣植株观赏性综合评价的特征性指标。BF1、BF19、BF10为排名前3位综合性状表现优良的沙枣单株。【结论】基于沙枣表型性状分析开展观赏性综合评价,为沙枣实生苗选种、早期选育沙枣优良植株及开发利用提供理论参考。 展开更多
关键词 沙枣 2年生植株 表型多样性 观赏性评价
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二年生白术药材33种禁用农药残留分析 被引量:1
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作者 张楠楠 吕光达 +2 位作者 王志强 黄艳梅 施志顺 《广州化工》 CAS 2024年第4期110-114,共5页
建立气相色谱串联质谱仪与超高效液相色谱串联质谱仪测定方法,通过内标法与外标法共同定量分析。用乙腈提取并用平行真空浓缩仪低温浓缩乙腈,再用乙腈稀释溶解样品最后通过亲水亲油平衡材料固相萃取柱净化,评价二年生白术中药材受33种... 建立气相色谱串联质谱仪与超高效液相色谱串联质谱仪测定方法,通过内标法与外标法共同定量分析。用乙腈提取并用平行真空浓缩仪低温浓缩乙腈,再用乙腈稀释溶解样品最后通过亲水亲油平衡材料固相萃取柱净化,评价二年生白术中药材受33种禁用农药的污染情况,结果表明,33种禁用农药标准曲线线性良好,相关系数均大于0.99,准确性与重复性回收率在61%~118%之间。30批二年生白术、甲拌磷、氟虫腈、甲基异柳磷检出,检出率为66.6%。二年生白术需关注甲拌磷、氟虫腈、甲基异柳磷等农药的残留。 展开更多
关键词 二年生白术 33种禁用农药 甲拌磷 氟虫腈 甲基异柳磷
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Variation of the East Asian Monsoon and the tropospheric biennial oscillation 被引量:9
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作者 LI ChongYin PAN Jing QUE ZhiPing 《Chinese Science Bulletin》 SCIE EI CAS 2011年第1期70-75,共6页
Study of the tropospheric biennial oscillation (TBO) has attracted significant interest since the 1980s.However,the mechanism that drives this process is still unclear.In the present study,ECMWF daily data were applie... Study of the tropospheric biennial oscillation (TBO) has attracted significant interest since the 1980s.However,the mechanism that drives this process is still unclear.In the present study,ECMWF daily data were applied to evaluate variation of the East Asian monsoon and its relationship to the TBO.First,the general East Asian monsoon index (EAMI) was delineated on the basis of a selected area using the 850 hPa u and v components.This new index may describe not only the characteristics of summer monsoons,but also the features of winter monsoons,which is crucial to understand the transition process between summer and winter monsoons.The following analysis of EAMI shows that there is a close relationship between summer and winter monsoons.In general,strong East Asian winter monsoons are followed by strong East Asian summer monsoons,and weak winter monsoons lead to weak summer monsoons.While strong (weak) summer monsoons followed by weak (strong) winter monsoons form a kind of 2-year cycle,which may be the possible mechanism leading to the TBO over the East Asian region. 展开更多
关键词 东亚季风指数 对流层 振荡 夏季季风 中期天气预报 冬季风 面积计算 过渡过程
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