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On the Chaotic Behavior and Predictability of the Real Atmosphere

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Advances in Atmospheric Sciences 1991年第4期8卷 407-420页

作者： yang peicai Institute of Atmospheric Physics Academia SinicaBeijing 100029

In this paper the concept of Chaos and its applications to the study of predictability theory is *** author's attempt is to give a general overview of ideas and methods involved in this problem to scientists,who are interested in the problem of predictability but not familiar with the theory of *** problem is discussed in 4 *** the first section,the concept of chaos and the study methods are outlined briefly;in the second section,the methods of quantitatively measuring the main characteristics of chaos which are the basis for the predictability theory are introduced;the third section discusses the time series analysis for directly studying chaotic phenomena in practical problems;and the last section presents some research results on the chaotic characteristics and the predictability of the real atmosphere.

关键词： Phase Space Lyapunov Exponent Chaotic System Correlation Dimension Chaotic Attractor

Introducing driving-force information increases the predictability of the North Atlantic Oscillation

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Atmospheric and Oceanic Science Letters 2019年第5期12卷 329-336页

作者： PAN Xinnong WANG Geli yang peicai Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Science University of Chinese Academy of SciencesBeijingChina

The North Atlantic Oscillation(NAO)is the most prominent mode of atmospheric variability in the Northern *** of the close relationship between the NAO and regional climate in Eurasia,North Atlantic,and North America,improving the prediction skill for the NAO has attracted much *** studies that focused on the predictability of the NAO were often based upon simulations by climate *** this study,the authors took advantage of Slow Feature Analysis to extract information on the driving forces from daily NAO index and introduced it into phase-space *** computing the largest Lyapunov exponent,the authors found that the predictability of daily NAO index shows a significant increase when its driving force signal is ***,the authors conducted a short-term prediction for the NAO by using a global prediction model for chaotic time series that incorporated the driving-force *** showed that the prediction skill for the NAO can be largely *** addition,results from wavelet analysis suggested that the driving-force signal of the NAO is associated with three basic drivers:the annual cycle(1.02 yr),the quasi-biennial oscillation(QBO)(2.44 yr);and the solar cycle(11.6 yr),which indicates the critical roles of the QBO and solar activities in the predictability of the NAO.

关键词： North Atlantic Oscillation slow feature analysis driving force characteristics time series prediction

2023年南京市通江河道血吸虫病传播风险评估

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华南预防医学 2024年第5期50卷 410-414页

作者：王毓谢朝勇杨佩才南京市疾病预防控制中心江苏南京210003

目的评估2023年南京市通江河道血吸虫病的传播风险,为强化通江河道地区血吸虫病防控措施和降低传播风险提供依据。方法在南京市滁河、便民河和水阳江3条通江河道地区开展钉螺监测、人畜活动情况调查及传染源监测,分析通江河道的血吸虫... 详细信息

目的评估2023年南京市通江河道血吸虫病的传播风险,为强化通江河道地区血吸虫病防控措施和降低传播风险提供依据。方法在南京市滁河、便民河和水阳江3条通江河道地区开展钉螺监测、人畜活动情况调查及传染源监测,分析通江河道的血吸虫病传播风险因素,采用三维风险矩阵法对其进行风险等级评估。结果在通江河道12个环境开展钉螺监测,活螺平均密度0.20只/框,未发现感染性钉螺。共10个环境有人群活动,共4个环境有牛羊放牧情况。对通江河道沿岸的居民开展血吸虫病筛查共7273人,血检阳性率2.17%。对捡获的57份野粪均进行毛蚴孵化法检测,未检出阳性。共捕获野鼠31只,野鼠密度2.58%。三维风险矩阵评估结果显示,栖霞区便民河和六合区滁河为中等风险,高淳区水阳江为高风险。结论南京市通江河道的血吸虫病传播风险的因素依然存在,便民河和滁河为中等风险,水阳江为高风险。建议相关部门加强通江河道的环境综合治理,强化区域联防联控,同时还需完善血吸虫病监测体系,及时发现和消除潜在的传播风险。

关键词：血吸虫病通江河道风险评估

A novel approach in predicting non-stationary time series by combining external forces

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Chinese Science Bulletin 2011年第28期56卷 3053-3056页

作者： WANG GeLi yang peicai BIAN JianChun ZHOU XiuJi Laboratory for Middle Atmosphere and Glotal Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Severe Weather Beijing 100081 China

In this paper, we investigate a novel technique that reconstructs the observed time series and incorporates driving forces. Furthermore, to illustrate and test the technique, we consider a couple of predictive experiments using ideal time series provided by the logistic and Lorenz systems with specific driving forces. The preliminary results show this approach can improve prediction proficiency to some extent, and the external forces play a similar role to that of state variables.

关键词：时间序列预测非平稳 Lorenz系统测试技术预测能力状态变量驱动力理想

Retrievals of over-ocean precipitable water from SSM/I by SOM network model

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Chinese Science Bulletin 1999年第11期44卷 1038-1041页

作者： Jianchun Bian Hongbin Chen peicai yang Daren Lu Peking Univ Dept Geophys Beijing 100871 Peoples R China Chinese Acad Sci Inst Atmospher Phys LAGEO Beijing 100029 Peoples R China

An SOM network model was developed for retrievals of the oceanic total precipitable water (PW) from the SSM/I, by using the SSM/I and radiosonde observation data set provided by the NASDA (Japan). The model was first trained by 5/6 of the data, and the other data were used to test the retrieval ability of the model. The retrieval results showed that the SOM network model was better than the routine operational algorithm.

关键词： SOM network SSM/I precipitable water.

The Prediction of Non-stationary Climate Series Based on Empirical Mode Decomposition

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Advances in Atmospheric Sciences 2010年第4期27卷 845-854页

作者：杨培才王革丽卞建春周秀骥 Key Laboratory for Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Chinese Academy of Meteorological Sciences

This paper proposes a new approach which we refer to as ＂segregated prediction＂ to predict climate time series which are nonstationary. This approach is based on the empirical mode decomposition method （EMD）, which can decompose a time signal into a finite and usually small number of basic oscillatory components. To test the capabilities of this approach, some prediction experiments are carried out for several climate time series. The experimental results show that this approach can decompose the nonstationarity of the climate time series and segregate nonlinear interactions between the different mode components, which thereby is able to improve prediction accuracy of these original climate time series.

关键词： EMD nonstationarity nonlinear system climate prediction time series prediction

Impacts of Future NO_x and CO Emissions on Regional Chemistry and Climate over Eastern China

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Advances in Atmospheric Sciences 2010年第4期27卷 750-760页

作者：王革丽杨培才刘传熙刘毅吕达仁 Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences

A coupled chemical/dynamical model （SOCOL-SOlar Climate Ozone Links） is applied to study the impacts of future enhanced CO and NO_x emissions over eastern China on regional chemistry and climate. The result shows that the increase of CO and NOx emissions has significant effects on regional chemistry, including NOx, CO, O_3, and OH concentrations. During winter, the CO concentration is uniformly increased in the northern hemisphere by about 10 ppbv. During summer, the increase of CO has a regional distribution. The change in O_3 concentrations near eastern China has both strong seasonal and spatial variations. During winter, the surface O_3 concentrations decrease by about 2 ppbv, while during summer they increase by about 2 ppbv in eastern China. The changes of CO, NO_x, and O_3 induce important impacts on OH concentrations. The changes in chemistry, especially O_3, induce important effects on regional climate. The analysis suggests that during winter, the surface temperature decreases and air pressure increases in central-eastern China. The changes of temperature and pressure produce decreases in vertical velocity. We should mention that the model resolution is coarse, and the calculated concentrations are generally underestimated when they are compared to measured results. However, because this model is a coupled dynamical/chemical model, it can provide some useful insights regarding the climate impacts due to changes in air pollutant emissions.

关键词： regional chemistry and climate NO_x and CO emissions eastern China

Interdecadal Variations of Phase Delays between Two Nio Indices at Different Time Scales

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Interdecadal Variations of Phase Delays between Two Nio In...

中国气象学会2005年年会

作者： BIAN Jianchun, and yang peicai (Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029)

Phase delays between two Ni?o indices—sea surface temperatures in Ni?o regions 1+2 and 3.4 (1950-2001) at different time scales are detected by wavelet analysis here. Analysis results show that there

关键词： period bifurcations different time scales phase delays interdecadal variation.

来源： cnki会议评论

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cnki会议

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气候系统的非平稳行为和预测理论

气象学报 2005年第5期63卷 556-570页

作者：杨培才周秀骥中国科学院大气物理研究所北京100029 中国气象科学研究院北京100081

到目前为止,有关非平稳复杂系统及其在气候预测中的应用研究(它有着比混沌系统更为复杂的行为)是一个较少被人理解并有重大科学意义的前瞻性研究课题。在大气运动中,气候正是一个典型的非平稳系统,但是现有的气候预测理论,包括统计预测... 详细信息

到目前为止,有关非平稳复杂系统及其在气候预测中的应用研究(它有着比混沌系统更为复杂的行为)是一个较少被人理解并有重大科学意义的前瞻性研究课题。在大气运动中,气候正是一个典型的非平稳系统,但是现有的气候预测理论,包括统计预测理论和非线性预测理论,几乎都无一例外地建立在平稳性假定的基础之上,这有悖于气候过程的基本性质,因此它有可能是导致气候预测水平低下的重要的理论原因。另外,近10年来,气候过程具有层次结构已经成为许多科学家的共识,但是如何发展和完善这一理论,使之成为一个完整的体系,人们似乎还没找到合适的途径。事实上,气候系统的多层次结构(它与通常的多尺度结构是两个完全不同的概念)正是产生非平稳行为的原因,而气候系统的非平稳特性正是层次结构的集中表现。在这样的思想指导下,文中系统地讨论了非平稳气候的一些基本问题和相应的预测理论,并为之搭起了一个初步的理论框架。

关键词：气候系统非平稳行为气候预测气象动力学混沌系统