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Progress in Natural Science:Materials International 2007年第10期17卷 1199-1207页

作者： Wang Yue, Lü Daren and Huo Juan(laboratory for middle atmosphere and global environment observation, institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china) laboratory for middle atmosphere and global environment observation Institute of Atmospheric Physics Chinese Acad. of Sci. Beijing 100029 China

A method is presented for determining the optical thickness (τc) and effective particle radius (re) of stratiform cloud layers from transmitted solar radiation measurements. A detailed study shows that the cloud optical thickness and effective particle radius of water clouds can be determined from transmission function measurements at 0.75 and 2.13.μm, provided that the scaled optical thickness τ′0.75>1 and re>5 μm. The wavelengths adopted by our study are similar to the channels of the moderate resolution imaging spectrometer (MODIS). The proposed method is invalid for optically thin clouds since transmission at 2.13.μm is less sensitive to re. The retrieval errors of τ′0.75 and re monotonically decrease with increasing τc. For clouds having τ′0.75≥2, the retrieval errors of τ′0.75 and re are below 10% and 20%, respectively. Transmissions at 0.75 and 1.65 μm can also be used to retrieve τc and re.

关键词： transmitted solar radiation ground-based retrieval cloud optical thickness cloud effective particle radius.

Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes

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Science china Earth sciences 2010年第4期53卷 591-602页

作者： ZHANG GuangShu1,WANG YanHui1,QIE XiuShu2,ZHANG Tong1,ZHAO YuXiang1,3,LI YaJun1 & CAO DongJie11 laboratory for Climate environment and Disasters of Western china,Cold and Arid Regions environmental and Engineering Research institute,chinese academy of sciences,Lanzhou 730000,china 2.laboratory for middle atmosphere and global environment observation(LAGEO),institute of atmospheric physics,chinese academy of sciences,Beijing 10002.,china 3 Department of physics,Tianshui Normal College,Tianshui 741001,china laboratory for Climate environment and Disasters of Western china Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China laboratory for middle atmosphere and global environment observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of physics Tianshui Normal College Tianshui China

A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,*** 3D images of the lightning progression have been obtained successfully for the first time in *** 3D-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field *** was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation *** preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×104 m/*** stepped leader of negative CG lightning flashes was trigged by negative initial ***,it propagated downward at a speed of 1.3×105 m/*** initial process of the positive CG lightning flashes was also a propagation process of negative *** streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this *** NBP was originated at altitude of about 10.5 km in the upper positive charge *** a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation *** source power of the NBP could approach 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 *** 3D propagation of this new type of lightning discharge was observed and obtained for the first time in *** possible initiation mechanism of this new type of light-ning is discussed here.

关键词： time-of-arrival(TOA) technique three dimensional lightning locating system discharge process narrow bipolar pulse new-type of IC lightning

Macrophysical properties of specific cloud types from radiosonde and surface active remote sensing measurements over the ARM Southern Great Plains site

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atmospheric and Oceanic Science Letters 2017年第1期10卷 29-35页

作者： ZHANG Jin-Qiang CHEN Hong-Bin Key laboratory of middle atmosphere and global environment observation Center of Technical Support and Service IAPCA

Accurate observation of clouds is challenging because of the high variability and complexity of cloud types and *** using the long-term cloud data collected during the ARM program at the Southern Great Plains central facility during 2001-2010,the consistencies and differences in the macrophysical properties of clouds between radiosonde and ground-based active remote sensing are quantitatively evaluated according to six cloud types：low;mid-low（ML）;high-midlow;mid;high-mid（HM）;and high.A similar variability trend is exhibited by the radiosonde and surface observations for the cloud fractions of the six cloud ***,the magnitudes of the differences between the two methods are different among the six cloud types,with the largest difference seen in the high *** distribution of the cloud-base height of the ML,mid,and HM clouds agrees in both methods,whereas large differences are seen in the cloud-top height for the ML and high *** cloud thickness variations generally agree between the two datasets for the six cloud types.

关键词： Cloud macrophysical properties cloud types radiosonde remote sensing

Fog Detection over china's Adjacent Sea Area by using the MTSAT Geostationary Satellite Data

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atmospheric and Oceanic Science Letters 2012年第2期5卷 128-133页

作者： LI Jun 1,2,HAN Zhi-Gang 3,CHEN Hong-Bin 1,ZHAO Zeng-Liang 3,and WU Hong-Yi 4 1 laboratory for middle atmosphere and global environment observation (LAGEO),institute of atmospheric physics,chinese academy of sciences,Beijing 10002.,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3 Beijing institute of Applied Meteorology,Beijing 10002.,china 4 Beijing Meteorological Bureau,Beijing 100089,china laboratory for middle atmosphere and global environment observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of chinese academy of sciences Beijing 100049 China Beijing institute of Applied Meteorology Beijing 100029 China Beijing Meteorological Bureau Beijing 100089 China

A fog threshold method for the detection of sea fog from Multi-function Transport Satellite (MTSAT1R) infrared (IR) channel data is *** method uses principle component analysis (PCA),texture analysis,and threshold detection to extract sea fog information.A heavy sea fog episode that occurred over china's adjacent sea area during 7 8 April 2008 was detected,indicating that the fog threshold method can effectively detect sea fog areas nearly 24 hours a ***-1R data from March 2006,June 2007,and April 2008 were processed using the fog threshold method,and sea fog coverage information was compared with the meteorological observation report data from *** hit rate,miss rate,and false alarm rate of sea fog detection were 66.1%,27.3%,and 33.9%,*** results show that the fog threshold method can detect the formation,evolution,and dissipation of sea fog events over period of time and that the method has superior temporal and spatial resolution relative to conventional ship *** addition,through MTSAT-1R data processing and a statistical analysis of sea fog coverage information for the period from 2006 to 2009,the monthly mean sea fog day frequency,spatial distribution and seasonal variation characteristics of sea fog over china's adjacent sea area were obtained.

关键词： sea fog MTSAT geostationary satellite spatial distribution seasonal variation

Improved ENSO simulation in regional coupled GCM using regressive correction method

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Science china Earth sciences 2007年第8期50卷 1258-1265页

作者： FU WeiWei1 & ZHOU GuangQing2 1 Nansen-Zhu International Research Center (NZC), institute of atmospheric physics, chinese academy of sciences (CAS), Beijing 10002., china 2 State Key laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics (LASG), institute of At-mospheric physics, CAS, Beijing 10002., china Nansen-Zhu International Research Center (NZC) Institute of Atmospheric Physics Chinese Academy of Sciences (CAS) Beijing China State Key laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics CAS Beijing China

A regressive correction method is presented with the primary goal of improving ENSO simulation in regional coupled GCM. It focuses on the correction of ocean-atmosphere exchanged fluxes. On the basis of numerical experiments and analysis, the method can be described as follows: first, driving the ocean model with heat and momentum flux computed from a long-term observation data set; the pro-duced SST is then applied to force the AGCM as its boundary condition; after that the AGCM’s simula-tion and the corresponding observation can be correlated by a linear regressive formula. Thus the re-gressive correction coefficients for the simulation with spatial and temporal variation could be obtained by linear fitting. Finally the coefficients are applied to redressing the variables used for the calculation of the exchanged air-sea flux in the coupled model when it starts integration. This method together with the anomaly coupling method is tested in a regional coupled model, which is composed of a global grid-point atmospheric general circulation model and a high-resolution tropical Pacific Ocean model. The comparison of the results shows that it is superior to the anomaly coupling both in reducing the coupled model ‘climate drift’ and in improving the ENSO simulation in the tropical Pacific Ocean.

关键词： anomaly coupling regressive correction method regional coupled model ENSO simulation

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2, JIAN Zhimin3 & HE Jinhai4 1. Nansen-Zhu International Research Center, institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china 2. institute of Climate and environment, chinese academy of Meteoro- logical sciences, Beijing 100081, china 3. laboratory of Marine Geology, Tongji University, Shanghai 200092, china 4. Department of atmospheric sciences, Nanjing institute of Meteorol- ogy, Nanjing 210044, china 5. Graduate School of the chinese academy of sciences, Beijing 100039, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China institute of Climate and environment Chinese Academy of Meteorological Sciences Beijing China laboratory of Marine Geology Tongji University Shanghai China Department of atmospheric sciences Nanjing Institute of Meteorology Nanjing China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Temporal and spatial variations of δ^(15)N and δ^(18)O for atmospheric N_2O above the oceanic surface from Shanghai to Antarctica

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Science china Earth sciences 2008年第6期51卷 899-910页

作者： ZHU RenBin1, LIU YaShu1, XU Hua2, MA Jing2 & SUN LiGuang1 1 institute of Polar environment, University of Science and Technology of china, Hefei 230026, china 2 State Key laboratory of Soil and Sustainable Agriculture, institute of Soil Science, chinese academy of sciences, Nanjing 210091, china institute of Polar environment University of Science and Technology of China Hefei China State Key laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing China

During the 22nd chinese Antarctic Research Expedition (chinaRE-22), the atmospheric gas samples above the oceanic surface and near the surface were collected on the track for the scientific ship "Xuelong" and on Millor Peninsula of eastern Antarctica, respectively, using the Tedlar gas bags. Every day the sampling times were 10:00 and 22:00 (local time), respectively. In the laboratory, high-precision measurement of the isotopic compositions for N2O in these gas samples was conducted using Thermo Finnigan MAT-253 Isotopic Mass Spectrometer with a fully automated interface for the pre-GC concen-tration (PreCon) of trace gases. The temporal and spatial variations of δ 15N and δ 18O in atmospheric N2O were analyzed. The mean δ 15N and δ 18O-N2O values above the oceanic surface were (7.21±0.50)‰ and (44.52±0.52)‰, respectively. From 30°N to Antarctica, the δ 15N (6.05‰―7.88‰) linearly increased with the rate of about 0.01‰ with the latitude while the δ 18O (43.05‰―48.78‰) showed a large fluctua-tion. The δ 15N negatively correlated with air temperature and N2O concentration, and slightly positively correlated with δ 18O. The summertime variations of δ 15N and δ 18O-N2O appeared the same trend on Millor Peninsula of eastern Antarctica. They significantly positively correlated with each other and negatively with N2O concentration. The δ 15N and δ 18O-N2O at different sites averaged (7.42±0.35)‰ and (44.69±0.49)‰, respectively, slightly higher than those above the oceanic surface, significantly higher than those of atmospheric N2O in the low-latitude regions of Northern Hemisphere. The predominant factors affecting the spatial variations of δ 15N and δ 18O values were also discussed. The isotopic data given in this study can help to investigate the global and regional N2O budgets.

关键词： nitrous oxide Antarctica atmosphere δ^(15)N δ^(18)O isotope ocean

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

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Science Bulletin 2011年第Z2期 3053-3056页

作者： WANG GeLi 1* , YANG PeiCai 1 , BIAN JianChun 1 & ZHOU XiuJi 2,3 1 laboratory for middle atmosphere and Glotal environment observation, institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china 2 chinese academy of Meteorological sciences, Beijing 100081, china 3 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： driving force non-stationary system climate prediction time series prediction

利用慢特征分析法提取二维非平稳系统中的外强迫特征

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气候与环境研究 2018年第3期23卷 287-298页

作者：范开宇王革丽李超潘昕浓成都信息工程大学大气科学学院成都610225 中国科学院大气物理研究所中层大气与全球环境探测重点实验室北京100029

慢特征分析法(Slow Feature Analysis,SFA)是一个从快变的信号中提取慢变特征的有效方法,它的提出丰富了人们对非平稳系统外强迫特征的重建手段。本文以Henon映射为基础,构造二维非平稳系统模型,尝试SFA方法在二维复杂非平稳系统中重建... 详细信息

慢特征分析法(Slow Feature Analysis,SFA)是一个从快变的信号中提取慢变特征的有效方法,它的提出丰富了人们对非平稳系统外强迫特征的重建手段。本文以Henon映射为基础,构造二维非平稳系统模型,尝试SFA方法在二维复杂非平稳系统中重建外强迫特征的能力。试验表明,SFA方法能够较好地从单时变参数Henon映射中提取出外强迫信号;通过结合小波变换技术,可以还原双时变参数Henon映射中的外强迫信号。另外,本文利用SFA方法重建了北京市气温的外强迫信号,分析其外强迫信号的尺度特征及其可能的物理机制。这些工作将为气候系统驱动力的研究提供新的思路。

关键词：慢特征分析法二维非平稳系统外强迫信号

Natural interdecadal weakening of East Asian summer monsoon in the late 20th century

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Science Bulletin 2005年第17期 109-115页

作者： JIANG Dabang1, 2 & WANG Huijun1 1. Nansen-Zhu International Research Center, institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china 2. Key laboratory of Regional Climate-environment Research for Tem-perate East Asia, chinese academy of sciences, Beijing 10002., china

Based on the reanalysis data throughout 1948―2002 as derived from the United States National Centers for environmental Prediction and National Center for Atmos-pheric Research, it is revealed that East Asian summer mon-soon (EASM) intensity weakens on an interdecadal timescale since the mid-1960s, and twice interdecadal jumps are re-corded in the EASM intensity index series in the late 20th century, respectively occurring in the mid-1960s and mid- to late 1970s. Six globally coupled atmosphere-ocean models’ outputs under the SRES A2 greenhouse gas and aerosol emission scenario, provided by the IPCC Data Distribution Center and the Hadley Center for Climate Prediction and Research, are then systematically examined. It follows that the above EASM weakening is not closely related to synchro-nizing anthropogenic global warming, and, therefore, it should be qualitatively natural change process. Over the 21st century, the EASM intensity is likely increased slightly by continually intensified greenhouse effect relative to the late 20th century.

关键词： East Asian summer monsoon interdecadal weakening global warming natural change.