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Multitime scale variations of sea surface temperature in the china seas based on the HadISST dataset

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Acta Oceanologica Sinica 2011年第4期30卷 14-23页

作者： JIN Qihua wang Hui Chinese Academy of meteorological Sciences China Meteorological Administration Beijing 100081 China national Marine Environmental Forecasting Center State Oceanic Administration Beijing 100081 China

The variability of the sea surface temperature（SST） in the china seas has been studied in seasonal,interannual and interdecadal scales based on the monthly data of HadISST spanning from 1870 to 2.07. The main results obtained are SST in the china offshore changes most actively at the seasonal scale with the intensity diminishing from north to south,as the temperature differences between summer and winter reaching 17 and 4 C in the northern and southern areas,respectively. Moreover,seasonal variation near the coastal regions seems relatively stronger than that far from the coastline;significant interannual variations are detected,with the largest positive anomaly occurring in 1998 in the overall area. But as far as different domains are concerned,there exists great diversity,and the difference is also found between winter and summer. Differed from the seasonal variations,where the strongest interannual variability takes place,resides to the south of that of the seasonal ones in the northern section,nevertheless in the South china Sea,the most significant interannual variability is found in the deep basin;interdecadal changes of summer,winter and annual mean SST in different domains likewise present various features. In addition,a common dominant warming in recent 2. a are found in the overall china offshore with the strongest center located in the vicinity of the Changjiang Estuary in the East china Sea,which intensifies as high as 1.3 C during the past 130 a.

关键词： china seas sea surface temperature multitime scale variations

Monitoring of the 2.11 spring low ozone events in the Arctic region

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Chinese Science Bulletin 2011年第27期56卷 2893-2896页

作者： LIU NianQing 1,2., HUANG FuXiang 1,2.wang WeiHe 1,2.1 {2. Satellite meteorological Center, beijing 100081, china 2.Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, china meteorological Administration, beijing 100081, china national Satellite meteorological Center Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration

Data from FY-3B SBUS and NOAA SBUV/2.were used to monitor ozone levels in the Arctic region from March 1 to April 5, 2.11. Results revealed a significant ozone depletion in the area, with total ozone levels between 2.0-2.0 DU. The ozone levels recorded were 100-2.0 DU below normal, and in some parts the levels were as low as 2.0 DU, indicating a mini ozone-hole. During the sampling period, the ozone depletion area underwent identifiable expansion and detraction, a rotation around the North Pole from the west to the east, and a longitudinal movement from the Pole, spreading to the mid latitudes. The effects of these rare low ozone events were not only felt in the Arctic, but also extended to densely populated areas between Europe and the middle of Russia. In this region, rapidly increasing levels of ultraviolet radiation were detected at the Earth's surface. Given the significant risk that this poses to both the environment and people's health, this occurrence has significant global implications.

关键词：北极地区臭氧水监测事件人口稠密地区中纬度地区 NOAA 调查结果

Ocean color products retrieval and validation around china coast with MODIS

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Acta Oceanologica Sinica 2010年第4期29卷 21-27页

作者： SUN Lingt GUO Maohua wang Xiaomei Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration （LRCVES/CMA） National Satellite Meteorological Center China Meteorological Administration Beijing 100081 China national Satellite Ocean Application Service State Oceanic Administration Beijing 100081 China

Waters along china coast are very turbid with high concentrations of suspended sediment nearly all the time,especially at the Hangzhou Bay,the Changjiang （yangtze） River Estuary and the shoal along Jiangsu *** these turbid and optically complex waters,the standard MODIS ocean color products tend to have invalid *** the water-leaving radiances in the near-infrared （NIR） are significant resulting from the strong scattering of suspended particles,the standard MODIS atmospheric correction algorithm often gets no results or produces significant *** because of the complex water optical properties,the OC3 model used in the standard MODIS data processing tends to get extremely high chlorophyll-a （Chl-a） *** this paper,we present an atmospheric correction approach using MODIS short wave infrared （SWIR） bands based on the fact that water-leaving radiances are negligible in the SWIR region because of the extreme strong absorption of water even in turbid waters.A regional Chl-a concentration estimation model is also constructed for MODIS from in situ *** algorithms are applied to MODIS Aqua data processing in the china coastal *** situ data collected in the Yellow Sea and the East china Sea in spring and autumn,2.03 are used to validate the *** good results have been *** is noted that water-leaving reflectance in the NIR bands are significant in waters along the china coast with high sediment *** satellite derived and in-situ reflectance spectra can match in the turbid waters along china coast,and there is relatively good linear relationship between satellite derived and in-situ *** RMSE value of Rrs（λ） is 0.0031 sr ？1 for all the nine ocean color bands （412.to 869 nm）.The satellite-derived Chl-a value is in the reasonable range and the root mean square percentage difference is 46.1%.

关键词： ocean color atmospheric correction chlorophyll-a MODIS china coastal region validation

Dipole anomaly in the Arctic atmosphere and winter Arctic sea ice motion

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Science china Earth Sciences 2005年第9期48卷 1529-1536页

作者： WU Bingyi1, ZHANG Renhe1 & wang Jia2.1. Chinese Academy of {2. Sciences, beijing 100081, china 2. International Arctic Research Center, University of Alaska Fairbanks, AK 99775, USA 1. Chinese Academy of meteorological Sciences 100081 Beijing China 2. International Arctic Research Center University of Alaska Fairbanks 99775 AK USA

This paper investigates a previously-ignored atmospheric circulation anomaly-di- pole structure anomaly in the arctic atmosphere, and its relationship with the winter sea ice mo- tion, based on analyses of the International Arctic Buoy Programme Data (1979―1998) and datasets from the national Center for Environmental Prediction (NCEP) and the national Center for Atmospheric Research (NCAR) for the period of 1960―2.02. The dipole structure anomaly is the second-leading mode of EOF of monthly mean SLP north of 70°N during the winter season (Oct.―Mar.), which accounts for 13% of the variance. One of its two anomaly centers is over the Canadian Archipelago; the other is situated over northern Eurasia and the Siberian marginal seas. Due to the dipole structure anomaly’s strong meridionality, it becomes an important mechanism to drive both anomalous sea ice export out of the Arctic Basin and cold air outbreaks into the Barents Sea, the Nordic Seas and northern Europe.

关键词： dipole anomaly, winter season, Arctic, sea ice motion, sea ice export.

Analysis of the severe group dust storms in eastern part of Northwest china

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Journal of Geographical Sciences 2002年第3期12卷 357-362页

作者： ZHOU Zijiang, wang Xiwen(1. national {2. Center, beijing 100081, china 2. Lanzhou Central {2.Observatory, Lanzhou 73002., china) national meteorological Center 北京 100081 Lanzhou Central meteorological Observatory Lanzhou 730020

Based on the available original dust storm records from 60 meteorological stations, we discussed the identification standard of severe dust storms at a single station and constructed a quite complete time series of severe group dust storms in the eastern part of Northwest china in 1954–2.01. The result shows that there were 99 severe group dust storms in this region in recent 48 years. The spatial distribution indicates that the Alax Plateau, most parts of the Ordos Plateau and most parts of the Hexi Corridor are the main areas influenced by severe group dust storms. In addition, the season and the month with the most frequent severe group dust storms are spring and April, accounting for 78.8% and 41.4% of the total events respectively. During the past 48 years the lowest rate of severe group dust storms occurred in the 1990s. Compared with the other 4 decades, on the average, the duration and the affected area of severe group dust storms are relatively short and small during the 1990s. In 2.00 and 2.01, there were separately 4 severe group dust storms as the higher value after 1983 in the eastern part of Northwest china.

关键词： eastern part of Northwest china severe group dust storms temporal and spatial distribution characteristics

Effects of 4DVAR with multifold observed data on the typhoon track forecast

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Chinese Science Bulletin 2003年第S2期48卷 93-98页

作者： wang Yunfeng, wang Bin, MA GANG & wang Yushun 1. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences. beijing 10002., china: 2. national Satellite meteorological Center, beijing 100081. china Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China

Effects of 4-dimension variational data assimi-lation (4DVAR) with multifold observed data on the typhoontrack forecast are studied, by using the MM5V3 model, theRTTOVS-5 model and their adjoint models. The data usedfor assimilation include large-scale background fields data,bogus data, cloud-derived wind data, satellite inverse data,and high resolution infrared radiation sounder data (HIRS).There are 5 typhoon cases are used to perform the numericalexperiments and assimilation experiments. The numericalresults show that with 4DVAR the initial fields can be greatlyimproved and the initial typhoon structure can be clearlydescribed.

关键词： multifold observed data 4DVAR typhoon track. DOI: 10.1360/03wd0456

Exploring formation mechanism and source attribution of ozone during the 2.19 Wuhan Military World Games:Implications for ozone control strategies

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Journal of Environmental Sciences 2024年第2期136卷 400-411页

作者： Lei Zhang Lili wang Runyu wang Nan Chen Yuan {2. Ke Li Jie Sun Dan Yao Yuesi wang Minghui Tao {2. Sun Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China Hubei Ecological Environment Monitoring Center Station Wuhan 430072China Guizhou Research and Designing Institute of Environmental Sciences Guizhou Academy of Environmental Science and DesignGuiyang 550081China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Environment Key Laboratory for Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China

A series of emission reduction measures were conducted in Wuhan,Central china,to ensure good air quality during the 7th Military World Games(MWG)in October *** better understand the implications for ozone(O_(3))pollution control strategies,we applied integrated analysis approaches based on the de-weathered statistical model,parameterization methods,chemical box model,and positive matrix factorization *** the MWG,concentrations of O_(3),NO_x,and volatile organic compound(VOCs),OFP(O_(3)formation potential),L_(OH)(OH radical loss rate)were 83μg/m^(3),43μg/m^(3),2. ppbv,188μg/m^(3),and 3.9 s^(-1),respectively,which were 2.%,18%,3%,15%,and 13%lower than pre-MWG values and 6%,39%,30%,33%,and 50%lower than post-MWG values,*** removing meteorological influence,O_(3)and its precursors during the MWG decreased largely compared with post-MWG values,and only O_(3),NO_(2.,and oxygenated VOCs(OVOCs)declined compared with pre-MWG values,which revealed the emission reduction measures during the MWG played an important role for O_(3)*** six VOCs sources,the mass contributions of biomass burning and solvents usage during the MWG decreased largely compared with pre-MWG values.O_(3)production was sensitive to VOCs and the key species were aromatics,OVOCs,and alkenes,which originated mainly from solvents usage,biomass burning,industrial-related combustion,and vehicle *** O_(3)concentration during the strict control was mainly caused by OVOCs reduction due to biomass burning ***,the O_(3)abatement strategies of Wuhan should be focused on the mitigation of high-reactivity VOCs.

关键词： VOCs Ozone Wuhan Military World Games Source apportionment Relative incremental reactivity Random forest

Expert consensus on endodontic therapy for patients withsystemic conditions

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International Journal of Oral Science 2024年第3期16卷 390-397页

作者： Xin Xu Xin Zheng Fei Lin Qing Yu Benxiang Hou Zhi Chen Xi Wei Lihong Qiu Wenxia Chen Jiyao Li Lili Chen Zuomin wang Hongkun Wu Zhiyue Lu jizhi Zhao Yuhong Liang Jin Zhao Yihuai Pan Shuang Pan Xiaoyan wang Deqin yang Yanfang Ren Lin Yue Xuedong Zhou State Key Laboratory of Oral Diseases&national Clinical Research Center for Oral Diseases&Department of Cariology and Endodontics West China Hospital of StomatologySichuan UniversityChengduChina Department of Cariology and Endodontology Peking University School and Hospital of Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research of Oral Biomaterials and Digital Medical Devices&Beijing Key Laboratory of Digital StomatologyPeking UniversityBeijingChina State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of Oral DiseasesDepartment of Operative Dentistry&EndodonticsSchool of StomatologyThe Fourth Military Medical UniversityXi’anChina Center for Microscope Enhanced Dentistry Beijing Stomatological HospitalCapital Medical UniversityBeijingChina State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyWuhan UniversityWuhanChina Department of Operative Dentistry and Endodontics Hospital of StomatologyGuanghua School of StomatologySun Yat-Sen University&Guangdong Provincial Key Laboratory of StomatologyGuangzhouChina Department of Endodontics School of StomatologyChina Medical UniversityShenyangChina College&Hospital of Stomatology Guangxi Medical UniversityNanningChina Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Stomatology Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina State Key Laboratory of Oral Diseases&national Center for Stomatology&national Clinical Research Center for Oral Diseases&Department of Geriatric Dentistry West China Hospital of StomatologySichuan UniversityChengduChina beijing Hospital National Center of GerontologyBeijingChina Department of Stomatology Peking Union Medical College Hospit

The overall health condition of patients significantly affects the diagnosis, treatment, and prognosis of endodontic diseases. Asystemic consideration of the patient’s overall health along with oral conditions holds the utmost importance in determining thenecessity and feasibility of endodontic therapy, as well as selecting appropriate therapeutic approaches. This expert consensus is acollaborative effort by specialists from endodontics and clinical physicians across the nation based on the current clinical evidence,aiming to provide general guidance on clinical procedures, improve patient safety and enhance clinical outcomes of endodontictherapy in patients with compromised overall health.

关键词： patients diagnosis prognosis

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, china national Satellite meteorological Center, china meteorological Administration, beijing 100081, china 1. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China 2. national Satellite meteorological Center China Meteorological Administration 100081 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.