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Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern china in warm seasons

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Science china Earth sciences 2008年第5期51卷 730-739页

作者： shi xiaohui1, xu XiangDe1, XIE LiAn2.1 {2. key laboratory of severe weather, chinese academy of meteorological sciences, beijing 100081, china 2.Department of Marine, Earth and Atmospheric sciences, North Carolina {2. University, Raleigh NC2.695-82.8, USA state key {2. of severe weather Chinese Academy of Meteorological Sciences Department of Marine Earth and Atmospheric Sciences North Carolina State University

Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 2. a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South china region during warm periods. Based on this finding, the region is referred to as a "significant impact zone" (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the "SI zone" over eastern china during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 2. a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the "SI zone". Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern china during a warm season.

关键词： warm season significant impact zone of aerosols climate change

Analysis to significant climate change in aerosol influence domain of beijing and its peripheral areas by EOF mode

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Science china Earth sciences 2005年第Z2期48卷 246-261页

作者： shi xiaohui, xu Xiangde, ZHANG Shengjun & DING Guoan {2. key laboratory of severe weather, chinese academy of meteorological sciences, beijing 100081, china Nanjing University of Information Science and Technology, Nanjing 2.0044, china state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China Nanjing University of Information Science and Technology Nanjing 210044 China state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Using the total ozone mapping spectrometer (TOMS) aerosol optical depth (AOD) data and the sunshine duration, fog days, low cloud cover (LCC), etc. meteorological data in 1979-2.00 in North {2., as well as empirical orthogonal function (EOF) mode statistical analyses method, the winter aerosol distributive character of beijing and peripheral city agglomeration and its influence effect on regional climate are investigated in this paper, especially the relation between aerosol influence effect and distinct change regions of eigenvectors of EOF mode. It is found from analyzing the regional distribution of the long-term averaged winter TOMS AOD that there is a large-scale relatively stable high value zone of aerosol concentration in the valley of the beijing and peripheral U-shape megarelief. A high correlation area of AOD between beijing and its southern peripheral exists in winter, and in this significant region of aerosol interaction, there is 'in-phase' character of the interannual variations of winter AOD, fog days, and LCCs. It indicates that the variations of aerosol in beijing and its peripheral areas have impacts on interannual changes of fog days and LCCs in this area. The EOF analyses of the meteorological data further reveal the climate change regions and long-term trends of winter sunshine duration-reducing, and LCC- and fog days-increasing in North {2.. The areas of significant changes of the first EOF eigenvectors (FEE) of sunshine duration, fog days, LCCs almost superpose on corresponding marked regions of interdecadal differences between the 1990s and 1980s, and all accord with the S-N zonal high value pattern and high correlation region of winter AOD in beijing and its peripheral areas. Interannual variations of their associated time coefficients (ATC) are in phase with that of regional mean AOD, and both of them have a secular rising trend. Results by EOF mode analyses depict the regional climatic change principal character of winter sunshine dura

关键词： city agglomeration, aerosol, climatic effect, EOF mode, influence domain.

Spatial character of the gaseous and particulate state compound correlation of urban atmospheric pollution in winter and summer

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Science china Earth sciences 2005年第S2期48卷 64-79页

作者： xu Xiangde, shi xiaohui, XIE Lian, DING Guoan, MIAO Qiuju, MA Jianzhong & ZHENG Xiangdong {2. key laboratory of severe weather, chinese academy of meteorological sciences, beijing 100081, china Nanjing University of Information Science and Technology, Nanjing 2.0044, china Department of Marine, Earth and Atmospheric sciences, North Carolina {2. University, Raleigh, NC2.695-82.8, USA National Climate Center, china meteorological Administration, beijing 100081, china state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China Nanjing University of Information Science and Technology Nanjing 210044 China Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC27695-8208 USA National Climate Center China Meteorological Administration Beijing 100081 China

The spatial/temporal variation information of atmospheric dynamic-chemical processes at observation site points of the "canopy" boundary of beijing urban building ensemble and over urban area "surface", as well as the seasonal correlation structure of the gaseous and par-ticulate states of urban atmospheric pollution (UAP) and its seasonal conversion feature at observation points are investigated, using the comprehensive observation data of the beijing City Air Pollution Observation Experiment (BECAPEX) in winter and summer 2.03 with a "point-surface" combined research approach. By using "one dimension spatial empirical orthogonal function (EOF)" principal component analysis (PCA) mode, the seasonal change of gaseous and particulate states of atmospheric aerosols and the association feature of pollutant species under the background of the complicated structure of urban boundary layer (UBL) are analyzed. The comprehensive analyses of the principal components of particle concentrations, gaseous pollutant species, and meteorological conditions reveal the seasonal changes of the complex constituent and structure features of the gaseous and particulate states of UAP to further trace the impact feature of urban aerosol pollution surface sources and the seasonal difference of the component structure of UAP. Research results suggest that in the temporal evolution of the gaseous and particulate states of winter/summer UAP, NOx, CO, and SO2.showed an "in-phase" evolution feature, however, O3 showed an "inverse-phase" relation with other species, all possessing distinctive dependent feature. On the whole, summer concentrations of gaseous pollutants CO, SO2. and NOx were obviously lower than winter ones, especially, the reduction in CO concentration was most distinctive, and ones in SO2.and NOx were next. However, the summer O3 concentration was more than twice winter one. Winter/summer differences in PM10 and PM2.5 particle concentrations were relatively not obvious, which ind

关键词： aerosol correlation structure principal component analysis.

Regional characteristics of the interdecadal turning of winter/summer climate modes in chinese mainland

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chinese Science Bulletin 2007年第1期52卷 101-112页

作者： shi xiaohui xu XiangDe Slate key laboratory of {2. weather Chinese Academy of Meteorological Sciences Beijing 100081 China Nanjing University of Information Science and Technology Nanjing 210044 China

Tomé and Miranda’s climate trend turning discriminatory model is used to identify the spatial-temporal characteristics of the interdecadal turning of winter/summer climate modes at stations and in eight sub-areas over chinese mainland based on the 1961–2.00 observations. It is found that the stations with close occurrence years of the interdecadal trend turning (ITT) and coincident trends after the ITT exhibit a zonal distribution. A view is accordingly proposed that the interdecadal turnings of climate modes in china have remarkably regional structures. The research results show that after the early 1980s, winter climate over chinese mainland overall trends towards a “warm-wet” mode, while summer climate had an abrupt change into “warm wet” mode in the late 1980s, suggesting that the time of the “warm-wet” mode turning for winter climate is earlier than that for summer climate. The regional characteristics and test results of the ITTs in eight sub-areas suggest that winter climate exhibits a distinctive “warm-dry” trend in North china after the late 1970s, and a slight “warm-dry” trend in Northeast china, South china, and Southwest china after the late 1980s. A “warm-wet” trend appears in the rest four sub-areas (the middle and lower reaches of the Yangtze River and the Huaihe River Valley, briefly Jianghuai, the east of the Tibetan plateau, and the east and west of Northwest china) after the early 1980s. The summer climate trends towards a “warm-dry” mode in Northeast china, North china and the east of Northwest china after the late 1980s, but a “warm-wet” mode appears in Southwest china and the east of the Tibetan plateau after the middle 1970s, as well as in Jianghuai and the west of Northwest china after the early 1980s. Specially, summer climate in South china started a “cold-wet” trend in 1984.

关键词：中国大陆气候夏季冬季

Aerosol influence domain of beijing and peripheral city agglomeration and its climatic effect

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chinese Science Bulletin 2006年第16期51卷 2016-2026页

作者： xu Xiangde shi xiaohui ZHANG Shengjun DING Guoan MIAO Qiuju ZHOU Li state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China Nanjing University of Information Science and Technology Nanjing 210044 China National Climate Center china meteorological Administration Beijing 100081 China

The aerosol distribution in beijing and peripheral cities agglomeration (BPCA) and its re- gional climatic effect are investigated on the basis of the statistical analyses of satellite Total Ozone Map- ping Spectrometer (TOMS) retrieval aerosol optical depth (AOD) and the meteorological data of sun{2.ne duration, fog days, and low cloud cover, observed at beijing and its peripheral meteorological stations. The analysis on multi-samples variational correction of the satellite remote sensing Moderate Resolution Imaging Spectroradiometer (MODIS) AOD under the clear sky and stable weather condition in conjunction with surface observations reveal that there was a “triangle-like” distribution pattern of the high values of aerosols in the southern “valley” of the “U-shape” megarelief of beijing and its peripheral areas. The distribution pattern suggests that the large-scale transfer and diffusion of city agglomeration pollutants might form a relatively persistent characteristic spatial distribution of city agglomeration pollutants much larger than city-scale. Under the background of the particular megarelief effect of beijing and periph- eral areas, the high value area of TOMS AOD, as well as regional correlation distribution between clear sky sun{2.ne duration and TOMS AOD are also similar to the composite image of MODIS AOD variational fields, that is to say, the effect of atmospheric aerosols was very distinctive in beijing and peripheral areas. The high value area of the negative correlation between clear sky sun{2.ne duration and TOMS AOD ap-proximately accorded with the significant negative value area of the sun{2.ne duration deviations of the 1980s to the 1990s, and the daily variations of the AOD also showed an anti-phase relation with those of clear sky sun{2.ne duration. The above high cor- relation area of the urban aerosol impact of beijing- Tianjin region leant towards south peripheral area, with its “center of gravity” in the south of beijing- Tianjin agglome

关键词：城市群北京气溶胶气候效应

The early-warning effects of assimilation of the observations over the large-scale slope of the “World Roof” on its downstream weather forecasting

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chinese Science Bulletin 2009年第4期54卷 706-710页

作者： PENG shiQiu xu XiangDe shi {2. WANG DongXiao ZHU YuXiang PU JingJiao Department of Marine Earth & Atmospheric Sciences North Carolina State University Raleigh NC 27695-8208 USA state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China key laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sci- ences Guangzhou 510301 China Training Centre of china meteorological Administration Beijing 100081 China Guangzhou Institute of Tropical and-Marine Meteorology China Meteorological Administration Guangzhou 510080 China Zhejiang Institute of meteorological sciences Hangzhou 310017 China

To improve the numerical simulation of the severe snow storms occurred in the south of china and the middle/lower reaches of Changjiang River during January of 2.08, the observations from the automatic {2. stations (AWS) over the Qinghai-Xizang Plateau (QXP) and its surrounding areas were assimi-lated into the {2. Research and Forecasts (WRF) model using multi-cycle 3-dimensional varia-tional data assimilation (3DVAR). Due to the large-scale special topography of the QXP and its sur-rounding areas which may reach up to the mid-troposphere, the AWS located at different height on the deep slope of the plateau are different to those located on plains and take a role analogous in some extent to that of radio soundings in obtaining the vertical "profile" information of the atmosphere, and have the advantages in the aspects of sampling frequency, location/height fixing, and synchronization. The information captured by these AWS may carry the early-warning "strong signals" in the upstream sensitive area for the downstream {2. systems to the east of the plateau and thus the assimilation of these AWS data is expected to lead to significant improvements on the simulation of the severe {2. system occurred in its downstream areas through adjusting the 3-dimensional structures of the atmospheric thermal-dynamics for the initial conditions of the model. This study indicates that the assimilated information of moisture, temperature and pressure carried in the observations of AWS over the Qinghai-Xizang Plateau and its surrounding areas is very important and useful in the forecasting of precipitation in its downstream areas.

关键词：雪暴数字模拟青海-西藏高原温度压力降水量

Spatial structure and scale feature of the atmospheric pollution source impact of city agglomeration

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Science china Earth sciences 2005年第Z2期48卷 1-24页

作者： xu Xiangde ZHOU Xiuji shi xiaohui state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

The spatial structure and multi-scale feature of the atmospheric pollution influence domain of beijing and its peripheral areas (a rapidly developed city agglomeration) is dissected and analyzed in this paper on the basis of the atmospheric pollution dynamic-chemical process observation data of the urban building ensemble boundary layer of the beijing City Air Pollution Observation Experiment (BECAPEX) in winter (February) and summer (August) 2.03, and relevant {2. elements and satellite retrieval aerosol optical depth (AOD), etc. comprehensive data with the dynamic-statistical integrated analysis of 'point-surface' spatial structure. Results show that there existed significant difference in the contribution of winter/summer different pollution emission sources to the component character of atmospheric pollution, and the principal component analysis (PCA) results of statistical model also indicate that SO2.and NOx dominated in the component structure of winter aerosol particle; instead, CO and NOxdominated in summer. Surface layer atmospheric dynamic and thermal structures and various pollutant species at the upper boundary of building ensembles at urban different observational sites of beijing in winter and summer showed an 'in-phase' variation and its spatial scale feature of 'influence domain'. The power spectrum analysis (PSA) shows that the period spectrum of winter/summer particle concentration accorded with those of atmospheric wind field: the longer period was dominative in winter, but the shorter period in summer, revealing the impact of the seasonal scale feature of winter/summer atmospheric general circulation on the period of atmospheric pollution variations. It is found that from analyzing urban area thermal heterogeneity that the multi-scale effect of beijing region urban heat island (UHI) was associated with the heterogeneous expansion of tall buildings area. In urban atmospheric dynamical and thermal characteristic spatial structures, the

关键词： atmospheric pollution source, contribution rate, boundary layer structure, multi-scale, backward trajec- tory, correlation vector, climatic effect, interaction of water, soil and atmosphere.

The impact of heterogeneity of land surface roughness length on estimation of turbulent flux in model

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Research in Cold and Arid Regions 2011年第1期3卷 31-40页

作者： Bin Chen XiangDe xu YuGuo Ding xiaohui shi state key {2. of severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China Nanjing University of Information Science ＆ Technology Nanjing Jiangsu 210044 China

Based on preliminary theoretical analysis and numerical experiment, it is found that land surface heterogeneity plays an important role in the models turbulent flux calculation. In nearly neutral atmosphere conditions, variation coefficient of sub-scale roughness length, cell-average roughness, and reference height are main factors affecting the calculation of grid turbulent fluxes. The first factor has a determinant role on calculation deviation. The relative error generated by roughness heterogeneity could be more than 40% in some cases in certain areas （e.g., in vegetation-climate transition belt）. Selecting a specific reference height may improve the calculation of turbulent flux. In stable or unstable atmosphere conditions, with sensible heat flux as an example, analysis shows that the discrepancy is correlated to the sub-grid distributions of mean wind velocity, potential temperature gradient between land surface and reference levels, and atmosphere stability near surface layer caused by the heterogeneity of land surface roughness. The calculation of turbulent flux is the most sensitive to stability in the above three factors. The above analysis shows that it is necessary to make a further consideration for the calculation deviation of the turbulent fluxes brought from land surface heterogeneity in the present numerical models.

关键词： land surface heterogeneity sub-grid scale grid turbulent flux surface roughness length

Improvement of Soil Moisture Simulation in Eurasia by the beijing Climate Center Climate System Model from CMIP5 to CMIP6

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Advances in Atmospheric sciences 2021年第2期38卷 237-252页

作者： Yinghan SANG Hong-Li REN xueli shi Xiaofeng xu Haishan CHEN School of Atmospheric sciences Nanjing University of Information Science&TechnologyNanjing 210044China state key {2. of severe weather Chinese Academy of Meteorological SciencesBeijing 100081China laboratory for Climate Studies&CMA-NJU Joint laboratory for Climate Prediction Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China china meteorological Administration Beijing 100081China

This study provides a comprehensive evaluation of historical surface soil moisture simulation(1979-2.12.over Eurasia at annual and seasonal time scales between two medium-resolution versions of the beijing Climate Center Climate System Model(BCC-CSM)—one that is currently participating in phase 6 of the Coupled Model Intercomparison Project(CMIP6),i.e.,BCC-CSM2.MR,and the other,BCC-CSM1.1m,which participated in *** show that BCC-CSM2.MR is more skillful in reproducing the climate mean states and standard deviations of soil moisture,with pattern correlations increased and biases reduced ***-CSM2.MR performs better in capturing the first two primary patterns of soil moisture anomalies,where the period of the corresponding time series is closer to that of reference *** show that BCC-CSM2.MR performs at a high level among multiple models of CMIP6 in terms of centered pattern correlation and“amplitude of variation”(relative standard deviation).In general,the centered pattern correlation of BCC-CSM2.MR,ranging from 0.61 to 0.87,is higher than the multi-model mean of CMIP6,and the relative standard deviation is 0.75,which surmounts the overestimations in most of the CMIP6 *** to the vital role played by precipitation in land-atmosphere interaction,possible causes of the improvement of soil moisture simulation are further related to precipitation in *** results indicate that a better description of the relation{2.p between soil moisture and precipitation and a better reproduction of the climate mean precipitation by the model may result in the improved performance of soil moisture simulation.

关键词： BCC-CSM soil moisture CMIP6 historical simulation Eurasia