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Ocean-atmosphere Teleconnections Play a Key Role in the Interannual Variability of Seasonal Gross Primary Production in China

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Advances in Atmospheric Sciences 2022年第8期39卷 1329-1342,I0011-I0016页

作者： Kairan YING Jing PENG Li DAN xiaogu zheng Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Since the 1950s,the terrestrial carbon uptake has been characterized by interannual variations,which are mainly determined by interannual variations in gross primary production(GPP).Using an ensemble of seven-member TRENDY(Trends in Net Land-Atmosphere Carbon Exchanges)simulations during 1951-2010,the relationships of the interannual variability of seasonal GPP in China with the sea surface temperature(SST)and atmospheric circulations were *** GPP signals that mostly relate to the climate forcing in terms of Residual Principal Component analysis(hereafter,R-PC)were identified by separating out the significant impact from the linear trend and the GPP *** showed that the seasonal GPP over China associated with the first R-PC1(the second R-PC2)during spring to autumn show a monopole(dipole or tripole)spatial structure,with a clear seasonal evolution for their maximum centers from springtime to *** dominant two GPP R-PC are significantly related to Sea Surface Temperature(SST)variability in the eastern tropical Pacific Ocean and the North Pacific Ocean during spring to autumn,implying influences from the El Niño-Southern Oscillation(ENSO)and the Pacific Decadal Oscillation(PDO).The identified SST and circulation factors explain 13%,23%and 19%of the total variance for seasonal GPP in spring,summer and autumn,respectively.A clearer understanding of the relationships of China’s GPP with ocean-atmosphere teleconnections over the Pacific and Atlantic Ocean should provide scientific support for achieving carbon neutrality targets.

关键词： interannual variation seasonal gross primary production ENSO PDO AO

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An Adaptive Estimation of Forecast Error Covariance Parameters for Kalman Filtering Data Assimilation

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Advances in Atmospheric Sciences 2009年第1期26卷 154-160页

作者： xiaogu zheng National Institute of Water and Atmospheric Research Wellington New Zealand

An adaptive estimation of forecast error covariance matrices is proposed for Kalman filtering data assim- ilation. A forecast error covariance matrix is initially estimated using an ensemble of perturbation forecasts. This initially estimated matrix is then adjusted with scale parameters that are adaptively estimated by minimizing -2log-likelihood of observed-minus-forecast residuals. The proposed approach could be applied to Kalman filtering data assimilation with imperfect models when the model error statistics are not known. A simple nonlinear model （Burgers＇ equation model） is used to demonstrate the efficacy of the proposed approach.

关键词： data assimilation Kahnan filter ensemble prediction estimation

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Optimizing photosynthetic and respiratory parameters based on the seasonal variation pattern in regional net ecosystem productivity obtained from atmospheric inversion

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Science Bulletin 2015年第34期60卷 1954-1961页

作者： Zhuoqi Chen Jing M.Chen xiaogu zheng Fei Jiang Jun Qin Shupeng Zhang Wenping Yuan Weiming Ju Gang Mo College of Global Change and Earth System Science Beijing Normal University International Institute for Earth System Science Nanjing University Department of Geography and Program in Planning University of Toronto Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of Sciences

In this study, we explore the feasibility of optimizing ecosystem photosynthetic and respiratory parameters from the seasonal variation of the net carbon flux. An optimization scheme is proposed to estimate two key parameters(Vmax25and Q10) by exploiting the seasonal variation in the net ecosystem carbon flux retrieved by an atmospheric inversion system. This scheme is implemented to estimate Vmax25 and Q10of the boreal ecosystem productivity simulator(BEPS) to improve its NEP simulation in the boreal North American region. Then, in situ NEE observations at six eddy covariance sites are used to evaluate the NEE simulations from BEPS with initial and optimized parameters. The results show that the performance of the optimized BEPS is superior to that of the BEPS with the default parameter values. These results implicate that it is possible to optimize ecosystem model parameters by different sensitivities of Vmax25 and Q10during growing and non-growing seasons through atmospheric inversion or data assimilation techniques.

关键词：净生态系统生产力模式优化季节变化呼吸参数反演大气光合 BEPS

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FELLER’S BOUNDARY IN ABSTRACT SPACES

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Chinese Annals of Mathematics 1983年第3期4卷 267-284页

作者：郑小谷

In this paper,most of the Feller’s boundaries are extended to abstract spaces,and ageneral expression of q-processes satisfing the Kolmogorov backward equation is obtainedwhen q(x) -q(x, A) is finite.

关键词： FELLER’S BOUNDARY IN ABSTRACT SPACES

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Mapping Near-surface Air Temperature, Pressure, Relative Humidity and Wind Speed over China's Mainland with High Spatiotemporal Resolution

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Advances in Atmospheric Sciences 2014年第5期31卷 1127-1135页

作者： LI Tao zheng xiaogu DAI Yongjiu YANG Chi CHEN Zhuoqi ZHANG Shupeng WU Guocan WANG Zhonglei HUANG Chengcheng SHEN Yan LIAO Rongwei College of Global Change and Earth System Science Beijing Normal University National Meteorological Information Center China Meteorological Administration

As part of a joint effort to construct an atmospheric forcing dataset for China's Mainland with high spatiotemporal reso- lution, a new approach is proposed to construct gridded near-surface temperature, relative humidity, wind speed and surface pressure with a resolution of 1 km× 1 km. The approach comprises two steps：（1） fit a partial thin-plate smoothing spline with orography and reanalysis data as explanatory variables to ground-based observations for estimating a trend surface; （2） apply a simple kriging procedure to the residual for trend surface correction. The proposed approach is applied to observations collected at approximately 700 stations over China's Mainland. The generated forcing fields are compared with the corresponding components of the National Centers for Environmental Predic- tion （NCEP） Climate Forecast System Reanalysis dataset and the Princeton meteorological forcing dataset. The comparison shows that, both within the station network and within the resolutions of the two gridded datasets, the interpolation errors of the proposed approach are markedly smaller than the two gridded datasets.

关键词： atmospheric forcing data land surface model thin-plate smoothing spline kriging reanalysis data

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AN ERGODIC THEOREM FOR GENERALIZED SIMPLE EXCLUSION PROCESSES WITH REVERSIBLE POSITIVE TRANSITION

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数学物理学报(英文版) 1987年第2期7卷 169-175页

作者：郑小谷曾文曲 Beijing Normal University Northeast University of Technology

Simple exclusion procosses are important infinite particle systems. This model was proposed by Spitzer （1）and studied extensively by Spitzer and Liggett （2）. On the basis of the model, Yan Shi-jian and Chen Mu-fa proposed generalized exclusion processes and obtained the construction of the processes. zheng Wen-qu obtained a necessary and sufficient condition of the reversibility and proved that the set of the reversible probability measures of such a process is equal to the set of it’s Gibbs states （3）. This paper is devoted to the ergodic theory of a generalized simple exclusion proess with the state space {0, 1, …, m} （m≥1, S is a countable set） and a reversible positive recurrent transition probability matrix P=（p（x, y））x,y∈s Refering （4）, the set of it’s invariant probability measures is described and the ergodic properties of the process is obtained. We also prove that the set of it’s reversible probability measures coinsides with the set of it’s invariant probability measures. So the main re

关键词： reversible exclusion infinite invariant devoted SIMPLE Gibbs Probability 切二 Borel

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ERGODIC THEOREMS FOR LINEAR GROWTH PROCESSES WITH DIFFUSION

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Chinese Annals of Mathematics,Series B 1989年第3期10卷 386-402页

作者：丁万鼎郑小谷 Department of Mathematics Anhui Normal University Wuhu Anhui China Department of Mathematics Beijing Normal Uuiversity Beijing China

In this paper a simple class of the infinite dimensional reaction-diffusion processes——the linear growth processes with diffusion is studied. This paper is devoted to the ergodicity of these processes. Tne exact value of parameters at which the change of phase occurs is given, the set of all translation invariant invariant measures and the corresponding domain of attraction for each translation invariant invariant measure are described.

关键词： invariant attraction exact devoted infinite supposed Probability minima finally uniqueness

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A MARTINGALE APPROACH TO Q-PROCESSES

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Chinese Science Bulletin 1987年第21期32卷 1457-1459页

作者：郑君礼郑小谷 Beijing Normal University

Ⅰ. INTRODUCTION The martingale approach was first proposed by Stroock and Varadhan when they studied the multidimensional diffusion processes. Holley, Stroock, Gray, Griffeath,

关键词： martingale 艺户 posed Borel topology totally measurable satisfying infinite integrable

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脉冲强光对油脂氧化稳定性的影响

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中国食品学报 2021年第3期21卷 183-192页

作者：曹少谦郑啸谷毛志康戚向阳浙江万里学院生物与环境学院浙江宁波315100 浙江省水产品加工技术研究联合重点实验室浙江宁波315100

为了探讨脉冲强光(IPL)对油脂氧化的影响,选取动物油(猪油)和植物油(大豆油)为对象,研究了不同IPL处理对二者POV值、CGV值、MDA值及自由基的影响。结果表明,IPL处理可促进两种油中过氧化物、羰基化合物、丙二醛和自由基的形成,且随着脉... 详细信息

为了探讨脉冲强光(IPL)对油脂氧化的影响,选取动物油(猪油)和植物油(大豆油)为对象,研究了不同IPL处理对二者POV值、CGV值、MDA值及自由基的影响。结果表明,IPL处理可促进两种油中过氧化物、羰基化合物、丙二醛和自由基的形成,且随着脉冲能量的增强,油脂的氧化程度增大。脉冲强光处理对猪油POV值、MDA值及自由基含量的影响均比大豆油大。动力学分析表明,脉冲强光对油脂氧化的影响符合半级反应动力学方程。

关键词：脉冲强光油脂氧化稳定性动力学分析

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UNIQUENESS CRITERION FOR q-PROCESSES

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Science in China,Ser.A 1983年第1期 11-24页

作者：陈木法郑小谷 Beijing Normal University

The uniqueness problem for the totally stable q-processes ha the ease of the state spaces being countable was solved by C. T. Hou. In this paper, we shall extend Hou’s theorem to arbitrary abstract state spaced.

关键词： Pro UNIQUENESS CRITERION FOR q-PROCESSES

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