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Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

Science china Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2. KANG Shichang2.3,5, SUN Junying4,5, Paul A. Mayewski2.& QIN Dahe5 1. National climate Center, china meteorological administration,{2., china 2. climate Change Institute, University of Maine, Orono, ME 04469, USA 3. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, china 4. Chinese Academy of meteorological Sciences,{2., china 5. Key laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, china National climate Center China Meteorological Administration Beijing China climate Change Institute University of Maine Orono ME USA Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Key laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Chinese Academy of meteorological Sciences Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 2.D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 2.D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (2.D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

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Solar release time of solar energetic particles and associated acceleration source in corona

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Chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1,2.3,4, TANG YuHua1 & HAN YanBen4 1 Department of Astronomy, Nanjing University, Nanjing 2.0093, china 2.Key laboratory of Radiometric Calibration and Validation for Environmental Satellites,{2., beijing 100081, china 3 National Center for Space Weather,{2., beijing 100081, china 4 National Astronomical Observatories, Chinese Academy of Sciences, beijing 100012. china Department of Astronomy Narijing University Nanjing 210093 China Key laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing 100081 China National Center for Space Weather China Meteorological Administration Beijing 100081 China Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1AU. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑

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The possible pivotal role of the eastward dust transport from Central Asia in the global temperature decrease

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Chinese Science Bulletin 2006年第A01期51卷 1-7页

作者： LIU Mingzhe & WEI Wenshou Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, china Graduate University of the Chinese Academy of Sciences, beijing 100039, china Chemical laboratory for Atmosphere, china meteorological administration, beijing 100081, china Urumqi Desert Meteorology, china meteorological administration, Urumqi 830002. china Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈... 详细信息

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈机制。这在北半球的 thehigh 纬度区域放大太阳的放射变化的效果，并且导致全球冰川的时代的出现。积极反馈机制在北半球的 thehigh 纬度区域以太阳的放射的减小开始。随后，全球温度减少，全球冰川的历元发生，在哪个枢轴的因素是从 CentralAsia 的东方灰尘运输。与积极反馈机制的理论，在 Milankovitch 理论的一些问题能被解决很好。

关键词：冰川间冰期高纬度地区北半球太阳辐射正反馈机制

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Three-year changes of surface albedo of degraded grassland and cropland surfaces in a semiarid area

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Chinese Science Bulletin 2008年第8期53卷 1246-1254页

作者： LIU HuiZhi1↑, TU Gang2.3 & DONG WenJie4 1 State Key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chi- nese Academy of Sciences, beijing 10002.,{2. 2.laboratory of Research for Middle-High Latitude Circulation System and East Asia Monsoon, china meteorological administration, Changchun 130062.{2. 3 Institute of meteorological Science of Jilin Province, Changchun 130062.{2. 4 National climate Center, beijing 100081,{2. State Key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China laboratory of Research for Middle-High Latitude Circulation System and East Asia Monsoon China Meteorological Administration Changchun China Institute of meteorological Science of Jilin Province Changchun China National climate Center Beijing China

Diurnal, seasonal and interannual variations of surface albedo of degraded grassland and cropland surfaces at a semiarid area of Tognyu have been investigated based on the continuous three years observational data from 2.03 to 2.05. The changes of surface albedo with solar elevation angle and soil moisture have been discussed also. It has been found that surface albedo has almost the same diurnal and seasonal variations on degraded grassland and cropland surfaces in the semiarid area, while sur- face albedo is large in winter and small in summer. The diurnal variation of the surface albedo has re- lationship with the weather condition. The diurnal cycle of the surface albedo likes the "U" shape curve in sunny day, while it is low-high after the rain, and high-low after the snow. The surface albedo has large variation in cloudy day, while it has no any variation in overcast day. The large difference of the surface albedo can be 0.04 in winter between two land surfaces, because the snow has large effects on the surface albedo in winter. The rainfall is an important factor in summer on the surface albedo, while the difference of the surface albedo is 0.01 only between two land surfaces. The differences of the surface albedo can also be 0.04 in autumn due to vegetation growing. The seasonal-average surface albeo from 2.03―2.05 is 0.2., 0.2., 0.2., 0.32.respectively in spring, summer, autumn and winter on the degraded grassland surface,while it is 0.2., 0.2., 0.2., 0.33 respectively in spring, summer, autumn and winter on the cropland surface. The surface albedo becomes smaller with the increase of solar elevation angle. When the solar elevation angle is greater than 40°, the surface albedo changes very little and tends to be a constant. The surface albedo has negative exponent functions with soil moisture in the growing season.

关键词：半干旱地区表面反照率土壤湿度草地退化

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Effects of nuclear chimney on climate

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Journal of Environmental Sciences 1990年第4期2卷 111-116页

作者： Gao Suhua, Ding Yihui, Pan Yaru and Zhang QingchenAcademy of meteorological Science State meteorological {2.,beijing 100081,china

In this paper, according to the data from several single nuclear explosion experiments of an equivalent to magnitude of million tons, and combined with meteorological data, their effects on the regional climate nave b... 详细信息

关键词： nuclear chimney nuclear explosion temperature change.

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Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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Science china Earth Sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3,YAN JingHua1 & HU HaiBo2.1 Institute of Tropical and Marine Meteorology,Chinese meteorological administration(CMA),Guangzhou 510080,{2. 2.Institute of Urban Meteorology,CMA,beijing 100089,{2. 3 State Key laboratory of Severe Weather,Chinese Academy of meteorological Sciences,beijing 100081,{2. Institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou China State Key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing China Institute of Urban Meteorology CMA Beijing China

With data mainly from Guangzhou mesonet Automatic Weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

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Principle and application of three-band gradient difference vegetation index

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Science china Earth Sciences 2005年第2期48卷 241-249页

作者： TANG Shihao, ZHU Qijiang, WANG Jindi, ZHOU Yuyu & ZHAO Feng Research Center for Remote Sensing and GIS, Department of Geography, beijing Normal University, beijing 100875,{2. National Satellite meteorological Center, china meteorological administration, beijing 100081,{2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University Beijing China National Satellite meteorological Center China Meteorological Administration Beijing China

Vegetation index is a simple, effective and experiential measurement of terrestrial vegetation activity, and plays a very important role in qualitative and quantitative remote sensing. Aiming at shortages of current vegetation indices, and starting from the analysis of vegetation spectral characteristics, we put forward a new vegetation index, the three-band gradient difference vegetation index (TGDVI), and established algorithms to inverse crown cover fraction and leaf area index (LAI) from it. Theoretical analysis and model simulation show that TGDVI has high saturation point and the ability to remove the influence of background to some degree, and the explicit functional relation with crown cover fraction and LAI can be established. Moreover, study shows that TGDVI also has the ability to partly remove the influence of thin cloud. Experiment in the Shunyi District, beijing, china shows that reasonable result can be reached using the vegetation index to retrieve LAI. We also theoretically analyzed the reason why the normalized difference vegetation index (NDVI) owns the low saturation point, and show that it is determined by the definition of NDVI and the characteristic of vegetation spectra, and is unavoidable to some degree. Meanwhile, through model simulation, we also indicate that the relationship between simple ratio vegetation index (SR) and LAI closes to a piecewise linear one instead of a linear one, which is mainly caused by the influence of background and different change rates of reflectance in red and infrared bands with LAI increasing.

关键词： vegetation index, remote sensing, LAI, crown cover fraction, remote sensing inversion.

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Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth Sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, YUAN Wei2.& GAO YuZhong3 1 Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 2.2. Training Centre, beijing 100081, china 3 Heilongjiang meteorological Observatory, Harbin 150030, china Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China china meteorological {2. Training Centre Beijing China Heilongjiang meteorological Observatory Harbin China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change

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Interdecadal trend turning of global terrestrial temperature and precipitation during 1951-2.02

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Progress in Natural Science:Materials International 2008年第11期18卷 1383-1393页

作者： Xiaohui Shi Xiangde Xu State Key laboratory of Severe Weather,Chinese Academy of meteorological Sciences,{2. 100081,china State Key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

A grid-by-grid counting of interdecadal trend turning(ITT)of annual mean surface air temperature(SAT)and total precipitation at 67,359 terrestrial grids in the period 1951-2.02.is *** analysis of the last ITTs of SAT and total precipitation in the period,in the context of both occurrence time and linear trends after the breakpoint,indicates that a warming trend has become highly significant across most reagent of the world in the late 2.th *** terrestrial grids have recorded an ITT of total precipitation in either the 1970s or 1980s,and 45.7% of the terrestrial grids in the study have seen a decreasing trend in total annual precipitation after the break- point,with the remaining 54.3% having experienced an increasing ***,global terrestrial regions have experienced either an increasingly warm and dry climate or an increasingly warm and wet *** analysis of ITT of regional mean SAT and total pre- cipitation in 2. regions shows that the Northern American continent has become increasingly warm and dry after the last interdecadal ***,the African continent has become increasingly warm and wet,with both Europe and most of Asia having the same *** South America and the West of Australia have experienced an opposite trend in climate,becoming increasingly cold and wet.

关键词： Global terrene Surface air temperature Precipitation Interdecadal trend turning

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A preliminary analysis of physical mechanism of transformation process from a landed typhoon into an extratropical cyclone

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Acta Oceanologica Sinica 1992年第4期11卷 525-535页

作者： Zhang Qiuqing and Ding Yihui 1. National Research Center for Marine. Environment Forecasts, beijing 100081, china2. Academy of {2. Science, State {2. administration, beijing 100081, china National Research Center for Marine Environment Forecasts Beijing 100081 China China

A diagnostic study is performed in the paper on the process of typhoon Norris (1980) transforming into an ex-tratropical cyclone after its landing over Southeast china. The main findings are as follows:The changes of kinetic energy are mainly attributed to the generation due to non-divergent wind. During the early stage of the typhoon landing, there exits only a small quantity of kinetic energy exchanging with the environment. And after it is transformed into an extratropical cyclone, a large amount of kinetic energy is exported from the system toward the *** horizontal and vertical flux-divergence terms of eddy available potenlial energy are the prominent sinks in the budgets of eddy kinetic energy. The generations of eddy kinetic energy due to both the barotropic and baroclinic processes are source terms. The former is remarkable during the initial stage. But after the depression is transformed into an extratropical cyclone, the roles of the generation by the barotropic and baroclinic processes are reversed, 1. e. , the latter has become more significant than the *** heating is the most dominant heat source. The terms of vertical heat flux by cumulus and large-scale motion are the major sinks. And the latter is prominent after the system is transformed into an extratropical cycfone.

关键词： A preliminary analysis of physical mechanism of transformation process from a landed typhoon into an extratropical cyclone

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