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Validation of Column-Averaged Dry-Air Mole Fraction of CO_2 Retrieved from OCO-2 Using Ground-Based FTS Measurements

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Journal of Meteorological Research 2018年第3期32卷 433-443页

作者： yanmeng bi Qian WANG Zhongdong YANG Jie CHEN Wenguang BAI National Satellite Meteorological Center China Meteorological Administration

In order to correctly use the column-averaged atmospheric COdry-air mole fraction(XCO) data in the COflux studies, XCOmeasurements retrieved from the Orbiting Carbon Observatory-2(OCO-2) in 2015 were compared with those obtained from the global ground-based high-resolution Fourier Transform Spectrometer(FTS) participating in the Total Carbon Column Observing Network(TCCON). The XCOretrieved from three observing modes adopted by OCO-2, i.e., nadir, target, and glint, were separately validated by the FTS measurements at up to eight TCCON stations located in different areas. These comparisons show that OCO-2 glint mode yields the best qualitative estimations of COconcentration among the three operational approaches. The overall results regarding the glint mode show no obvious systematic biases. These facts may indicate that the glint concept is appropriate for not only oceans but also land regions. Negative systematic biases in nadir and target modes have been found at most TCCON sites. The standard deviations of XCOretrieved from target and nadir modes within the observation period are similar, and larger than those from glint mode. We also used the FTS site in Beijing, China, to assess the OCO-2 XCOin 2016. This site is located in a typical urban area, which has been absent in previous studies. Overall, OCO-2 XCOagrees well with that from FTS at this site. Such a study will benefit the validation of the newly launched TanSat products in China.

关键词： Orbiting Carbon Observatory-2(OCO-2) Fourier Transform Spectrometer(FTS) carbon dioxide(CO2) validation

Responses of Saline Soil Properties and Cotton Growth to Different Organic Amendments

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Pedosphere 2018年第3期28卷 521-529页

作者： WU Yupeng LI Yufei ZHANG Yi bi yanmeng SUN Zhenjun College of Resources and Environment Huazhong Agricultural University Wuhan 430070( China) College of Resources and Environmental Sciences China Agricultural University Beijing 100194( China) Institute of Plant Nutrition and Resources Beijing Academy of Agriculture and Forestry Sciences Beijing 100097( China) School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen 518000( China)

Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments （e.g., cattle dung, vermicompost, biofertilizer） and earthworm inoculations （Eisenia fetida） on saline soils and cotton growth were investigated during i year of cotton cultivation. Compared to the control （applied with inorganic NPK fertilizer）, applying organic amendments improved soil physicochemical properties. biofertilizer application improved available nutrient content, reduced short-term soil electrical conductivity, and produced the highest cotton yield, whereas cattle dung and vermicompost applications resulted in higher soil organic matter content. Application of organic amendments significantly increased soil microbial biomass carbon during the flowering period, which sharply declined at harvest. This was especially true for the biofertilizer treatment, which also exhibited lower nematode abundance compared with the other organic materials. Earthworm inoculation following cattle dung application failed to significantly change soil physicochemical properties when compared to the treatments without earthworm inoculation. Results suggest that biofertilizer application to saline soil would improve soil nutrient status in the short-term, whereas cattle dung application would improve soil organic matter content and increase soil organism abundance to a greater extent. However, different strategies might be required for long-term saline soil remediation.

关键词： biofertilizer cattle dung earthworm inoculation saline soil remediation vermicompost

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

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Science Bulletin 2018年第22期63卷 1502-1512页

作者： Shanshan Du Liangyun Liu Xinjie Liu Xiao Zhang Xingying Zhang yanmeng bi Lianchong Zhang Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100094China University of Chinese Academy of Sciences Beijing 100049China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China

The first Chinese Carbon Dioxide Observation Satellite Mission(TanSat), which was launched on December 21, 2016, is intended to measure atmospheric CO_2 *** high spectral resolution(0.044 nm) and high SNR(360 at 15.2 mW m^(-1) sr^(-1) nm^(-1)) measurements in the region of the O_2-A band of the Atmospheric Carbon dioxide Grating Spectroradiometer(AGCS) module onboard TanSat make it possible to retrieve solar-induced chlorophyll fluorescence(SIF) from TanSat observations at the global *** paper aims to explore the potential of the TanSat data for global SIF retrieval.A singular vector decomposition(SVD) statistical method was employed to retrieve SIF using radiance over a micro spectral window(～2 nm) around the Fe Fraunhofer lines(centered at 758.8 nm).The global SIF at 758.8 nm was successfully retrieved with a low residual error of 0.03 mW m^(-1) sr^(-1) nm^(-1).The results show that the spatial and temporal patterns of the retrieved SIF agree well with the global terrestrial vegetation *** monthly SIF products retrieved from the TanSat data were compared with other remote sensing datasets, including OCO-2 SIF, MODIS NDVI, EVI and *** overall consistency between TanSat and OCO-2 SIF products(R^2= 0.86) and the consistency of the spatial patterns and temporal variations between the TanSat SIF and MODIS vegetation indices and GPP enhance our confidence in the potential and feasibility of TanSat data for SIF ***, therefore, provides a new opportunity for global sampling of SIF at fine spatial resolution(2 km × 2 km), thus improving photosynthesis observations from space.

关键词： TanSat Solar-induced chlorophyll fluorescence Singular vector decomposition Vegetation index MODIS OCO-2 GPP

Validation results of NmF2 and hmF2 derived from ionospheric density profiles of GNOS on FY-3C satellite

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Science China(Technological Sciences) 2018年第9期61卷 1372-1383页

作者： YANG GuangLin SUN YueQiang BAI WeiHua ZHANG XiaoXin LIU CongLiang MENG XiangGuang bi yanmeng WANG DongWei ZHAO DanYang National Space Science Center China Academy of Sciences Beijing 100190 China Key Laboratory of Space Weather National Center for Space Weather China Meteorological Administration Beijing 100081 China National Satellite Meteorological Center Beijing 100081 China Beijing Key Laboratory of Space Environment Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The first Global Navigation Satellite System Occultation Sounder(GNOS) which is compatible of both Bei Dou System(BDS)and Global Positioning System(GPS) was successfully launched into orbit onboard the Feng Yun 3 C satellite(FY-3 C) on September 23, 2013, and it has already gathered a large amount of ionosphere radio occultation(RO) data so far. However, the detailed analysis and validation of GPS ionosphere RO data have not been done up to now. Therefore, this paper discusses the configuration of the FY-3 C GNOS, the methods and results of GPS ionosphere occultation processment, the quality analysis of the GPS ionosphere RO products, and the precision consistency between the GNOS GPS ionosphere RO product and ionosonde data. The peak electron density(Nm F2) correlation coefficient is 0.97, the corresponding standard deviation is 16.08%. The peak value altitude(hm F2) correlation coefficient is 0.89, and the corresponding standard deviation is 23.79 km. The in-orbit operation of GNOS provides a basis data set for the monitoring, forecasting and research of ionosphere's space weather.

关键词： radio occultation Global Navigation Satellite System BeiDou System ionosphere

Fast CO_(2) Retrieval Using a Semi-Physical Statistical Model for the High-Resolution Spectrometer on the Fengyun-3D Satellite

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Journal of Meteorological Research 2022年第2期36卷 374-386页

作者： yanmeng bi Peng ZHANG Zhongdong YANG Qian WANG Xingying ZHANG Chengbao LIU Pengmei XU Lizhou HOU Junyu KE Naiqiang ZHANG Innovation Center for Fengyun Meteorological Satellite Key Laboratory of Radiometric Calibration and Validation for Environmental SatellitesNational Satellite Meteorological CenterChina Meteorological AdministrationBeijing 100081 China Academy of Space Technology Beijing 100081 Huayun ShineTek Beijing 100081

China’s Fengyun-3D meteorological satellite launched in December 2016 carries the high-resolution greenhouse-gases absorption spectrometer(GAS)aimed at providing global observations of carbon dioxide(CO_(2)).To date,GAS is one of the few instruments measuring CO_(2) from the near-infrared *** orbit,the oxygen(O_(2))A band suffers a disturbance,and the signal-to-noise ratio(SNR)is significantly lower than the nominal *** leads to difficulties in the retrieval of surface pressure and hence a degradation of the retrieval of the column-averaged CO_(2) dry air mole fraction(XCO_(2))if a full physics retrieval algorithm is ***,a fast CO_(2) inverse method,named semi-physical statistical algorithm,was developed to overcome this *** instrument characteristics,the semi-physical statistical algorithm,and the results of comparison with ground-based measurements over land were introduced in this ***_(2) can be obtained from three bands,namely,the O_(2) A,weak CO_(2),and strong CO_(2) bands,with compensation from the Medium Resolution Spectral Imager-2(MERSI-2)products,ECMWF Reanaly-sis v5(ERA-5)data,and Total Carbon Column Observing Network(TCCON)*** eigenvectors of covariance matrices and the least square fits were used to derive retrieval coefficients and yield cloud-free *** addition to the GAS radiance,some key factors necessary for the accurate estimations of XCO_(2) were also taken as input information(e.g.,air mass,surface pressure,and a priori XCO_(2)).The global GAS XCO_(2) restricted over land was compared against the simultaneously collocated observations from *** retrieval algorithm can mitigate the issue caused by the low SNR of the O_(2) A band to a certain ***,through site-by-site comparisons,GAS XCO_(2) agreed well with the average precision(1σ)of 1.52 ppm and bias of−0.007 *** seasonal variation trends of GAS XCO_(2) can be clearly seen at TCCON sites on the 1-yr timescale.

关键词： carbon dioxide fast retrieval Fengyun-3 high-resolution spectrometer

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蚯蚓调控土壤微生态缓解连作障碍的作用机制

生物多样性 2018年第10期26卷 1103-1115页

作者：毕艳孟孙振钧中国农业大学资源与环境学院北京100193 中国医学科学院北京协和医学院药用植物研究所北京100193

连作障碍不仅严重影响作物产量,而且会导致土壤生物多样性下降、有益微生物减少及病原菌增加等一系列微生态失衡问题。土壤微生态失衡反作用于植物,导致植物发生更严重的病害、减产等。作为土壤生态系统工程师,蚯蚓的取食、掘洞和爬行... 详细信息

连作障碍不仅严重影响作物产量,而且会导致土壤生物多样性下降、有益微生物减少及病原菌增加等一系列微生态失衡问题。土壤微生态失衡反作用于植物,导致植物发生更严重的病害、减产等。作为土壤生态系统工程师,蚯蚓的取食、掘洞和爬行等活动对土壤微生态具有重要的调控作用,既可以改善土壤环境,又可以强化土壤生物群落功能,有望为缓解作物的连作障碍问题提供一条新途径。本文总结了土壤微生态与土壤功能维持及蚯蚓调控土壤生物作用的研究进展,在此基础上,结合蚯蚓对化感物质降解作用的研究,分析了蚯蚓通过调控土壤微生态缓解作物连作障碍的微生物作用机制的三条途径:直接调控微生物群落、通过改变化感物质组成以及通过调控土壤动物区系调控微生物群落。蚯蚓对微生物群落的调控可改善失衡的土壤根际微生态,有效缓解作物连作障碍。

关键词：蚯蚓连作障碍土壤动物化感物质土壤微生物

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海南GPS网探测对流层水汽廓线的试验研究

应用气象学报 2008年第4期19卷 412-419页

作者：毕研盟毛节泰毛辉国家卫星气象中心北京100081 北京大学物理学院大气科学系北京100871 深圳市气象局深圳518001

介绍了2005年11月在海南地区进行的一次地基GPS小网观测试验。试验目的是研究利用组网的GPS倾斜路径观测进行对流层水汽层析反演,给出站点上空水汽的垂直廓线结构信息。概述了试验中GPS原始数据处理方法以及层析反演的方法。将GPS层析... 详细信息

介绍了2005年11月在海南地区进行的一次地基GPS小网观测试验。试验目的是研究利用组网的GPS倾斜路径观测进行对流层水汽层析反演,给出站点上空水汽的垂直廓线结构信息。概述了试验中GPS原始数据处理方法以及层析反演的方法。将GPS层析得到的水汽垂直廓线与海口站探空观测的水汽廓线进行了对比,结果表明:二者一致性较好,均方根误差在0.5 g.m-3左右,层析结果较好地反映出试验期间水汽减少、大气变干的过程。另外,采用3种不同的先验信息方案测试分析了GPS层析的结果,表明GPS观测量对水汽先验信息有明显的调整作用。并对GPS水汽层析中可能存在的问题进行了讨论。试验证明高时间分辨率的GPS观测有能力层析出GPS测站上空水汽的廓线信息。

关键词： GPS 水汽层析

应用全球定位系统、太阳光度计和探空仪探测大气水汽总量的对比分析

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气象学报 2011年第3期69卷 528-533页

作者：毕研盟杨忠东李元国家卫星气象中心北京100081

介绍了应用全球定位系统(GPS)和太阳光度计估算大气水汽总量的方法。大气中的水汽会对GPS信号的传播造成显著的影响,故可以利用GPS观测估算水汽总量或可降水量(PW);在近红外940 nm波段,水汽对太阳直射辐射的吸收作用会直接影响到太阳光... 详细信息

介绍了应用全球定位系统(GPS)和太阳光度计估算大气水汽总量的方法。大气中的水汽会对GPS信号的传播造成显著的影响,故可以利用GPS观测估算水汽总量或可降水量(PW);在近红外940 nm波段,水汽对太阳直射辐射的吸收作用会直接影响到太阳光度计观测的信号,利用水汽吸收透过率与水汽量的关系,应用太阳光度计的辐射观测资料也可以反演出无云情况下的水汽总量。将锡林浩特观象台2008年5—7月的GPS、CE-318型太阳光度计和探空仪3种观测的水汽量进行了比较,三者对水汽量的变化趋势描述较为吻合,相关系数在0.88以上,说明GPS和太阳光度计都能捕捉到大气中的水汽变化信息;但在水汽量的具体数值上存在差异。统计分析表明:相对于探空来说,GPS-PW稍高于探空值约0.18 g/cm2,太阳光度计PW值则低于探空。太阳光度计便于携带,观测简便;GPS可全天观测无需标定,利用GPS-PW对太阳光度计反演中的模拟参数进行校正是一种可行的方法。

关键词：水汽总量全球定位系统(GPS) 太阳光度计遥感

山基和地基GPS联合探测大气折射率廓线的试验研究

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高技术通讯 2008年第8期18卷 857-862页

作者：曹云昌胡雄符养杨光林毕研盟国家卫星气象中心北京100081 大气探测技术中心北京100081 中国科学院空间科学与应用研究中心北京100080 北京应用气象研究所北京100029

通过在河北省雾灵山及其周边地区开展的山基 GPS 掩星观测和层析试验,利用掩星和层析反演大气折射率的方法,共获取575条山基掩星的折射率廓线和120条 GPS层析的湿折射率廓线。比较山基掩星和探空获取的大气折射率表明,二者系统偏差在1%... 详细信息

通过在河北省雾灵山及其周边地区开展的山基 GPS 掩星观测和层析试验,利用掩星和层析反演大气折射率的方法,共获取575条山基掩星的折射率廓线和120条 GPS层析的湿折射率廓线。比较山基掩星和探空获取的大气折射率表明,二者系统偏差在1%左右,标准差为2%～3%,不同接收机反演的折射率符合精度优于1%,表明所选用的接收机在地面试验中基本可以满足对大气掩星观测的需求;山基掩星、GPS 层析和探空三种方法获取的大气湿折射率比较表明,三者具有很好的一致性,这从另一个方面进一步验证了山基掩星观测的效果;试验表明在低层山基掩星具有很好的垂直分辨率和精度,可以和 GPS 层析对整个对流层的探测互为补充,在大气探测方面具有重要的潜在应用价值。

关键词：山基掩星 GPS层析大气折射率 GPS气象学