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Global Water Vapor Content Decreases from 2003 to 2012： An Analysis Based on MODIS Data

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Chinese Geographical Science 2017年第1期27卷 1-7页

作者： MAO Kebiao chen jingming LI Zhaoliang MA Ying SONG Yang TAN Xuelan Yang Kaixian National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Geography University of Toronto Toronto M5S 3G3 Canada School of Geographical Sciences Northeast Normal University Changchun 130024 China College of Resources and Environments Hunan Agricultural University Changsha 410128 China Department of Geography University of Cincinnati Cincinnati 45221 USA

Water vapor in the earth′s upper atmosphere plays a crucial role in the radiative balance, hydrological process, and climate change. Based on the latest moderate-resolution imaging spectroradiometer(MODIS) data, this study probes the spatio-temporal variations of global water vapor content in the past decade. It is found that overall the global water vapor content declined from 2003 to 2012(slope b = –0.0149, R = 0.893, P = 0.0005). The decreasing trend over the ocean surface(b = –0.0170, R = 0.908, P = 0.0003) is more explicit than that over terrestrial surface(b = –0.0100, R = 0.782, P = 0.0070), more significant over the Northern Hemisphere(b = –0.0175, R = 0.923, P = 0.0001) than that over the Southern Hemisphere(b = –0.0123, R = 0.826, P = 0.0030). In addition, the analytical results indicate that water vapor content are decreasing obviously between latitude of 36°N and 36°S(b = 0.0224, R = 0.892, P = 0.0005), especially between latitude of 0°N and 36°N(b = 0.0263, R = 0.931, P = 0.0001), while the water vapor concentrations are increasing slightly in the Arctic regions(b = 0.0028, R = 0.612, P = 0.0590). The decreasing and spatial variation of water vapor content regulates the effects of carbon dioxide which is the main reason of the trend in global surface temperatures becoming nearly flat since the late 1990 s. The spatio-temporal variations of water vapor content also affect the growth and spatial distribution of global vegetation which also regulates the global surface temperature change, and the climate change is mainly caused by the earth's orbit position in the solar and galaxy system. A big data model based on gravitational-magmatic change with the solar or the galactic system is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatio-temporal variations of global water vapor content, vegetation and temperature at large spatio-temporal scale. This comprehensive examination of water vapor changes p

关键词： water vapor content climate change moderate-resolution imaging spectroradiometer(MODIS)

Global vegetation change analysis based on MODIS data in recent twelve years

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High Technology Letters 2016年第4期22卷 343-349页

作者：毛克彪 Li Zhaoliang chen jingming Ma Ying Liu Guang Tan Xuelan Yang Kaixian National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences International Institute for Earth System Science Nanjing University State Key Laboratory of Remote Sensing Science Institute of remote sensing and Digital Earth Research Institute and Beijing Normal University College of Resources and Environments Hunan Agricultural University Department of Geography University of Cincinnati

Vegetation cover change is critical for understanding impacts and responses of vegetation to climate change. A study found that vegetation in the regions between 45°N-70°N was increasing using normalized difference vegetation index( NDVI) from 1981 to 1991 ten years ago. The global vegetation growth has changed because of climate change in recent twelve years( 2001- 2012). After thorough analysis based on satellite data,it is found that it is evident that the global vegetation changed( NDVI) little,and it is increasing slightly in Northern hemisphere while it is decreasing slightly in Southern Hemisphere. For different latitudes,vegetation is increasing 0.17% every year from 60°N to 70 °N( R^2= 0.47,P > 0.013),while the vegetation is decreasing 0.11% every year from 10°N to 10° S( R^2= 0.54,P > 0.004). For different continents,the vegetation in South America is decreasing 0.16% every year( R^2= 0.78,P > 0.0001) and it is increasing 0.05% every year in Asia( R^2= 0.28,P > 0.072) and 0.25% every year in Oceania( R^2= 0.24,P > 0.1). The analysis of global vegetation in different seasons indicates that spatial distribution of global temperature and water vapor will affect the spatial distribution of vegetation,in turn,the spatial distribution of vegetation will also regulate the global temperature and water vapor spatial distribution at large scale. The growth and distribution of vegetation are mainly caused by the orbit of the celestial bodies,and a big data model based on gravitational-magmatic change with the solar or the galactic system as its center is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatial-temporal variations of global vegetation and temperature at large scale. These findings promise a holistic understanding of the global climate change and potential underlying mechanisms.

关键词： vegetation global climate change remote sensing

Spatial and temporal variations of forest LAI in China during 2000-2010

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Chinese Science Bulletin 2012年第22期57卷 2846-2856页

作者： LIU YiBo JU WeiMin chen jingming ZHU GaoLong XING BaiLing ZHU JingFang HE MingZhu International Institute for Earth System Sciences Nanjing UniversityNanjing 210093China Department of Geography Minjiang UniversityFuzhou 350108China

Forests are crucial terrestrial *** leaf area index (LAI) is a key parameter determining the exchange of matter and energy between the atmosphere and the ground *** this study,MOD 09A1 and MCD 43A1 data were input into an inversion model based on the 4-scale geometric optical model to retrieve 8-d 500 m LAI products in China during the period 2000 to *** resulting LAI product was validated using LAI measured in 6 typical *** spatial and temporal variations of forest LAI and its relationships with temperature and precipitation were *** results show that the accuracy of the 500 m LAI product was above 70% in the 6 typical areas,indicating the reliability of this *** 2000 to 2010,forest LAI in northeast,north,and south central China showed increasing ***,forest LAI in southeast and parts of southwest China showed downward trends,mainly because of the significant decrease observed during the period 2008 to *** mean forest LAI positively correlated with annual mean temperature (AMT) in northeastern China and negatively correlated with AMT in southwest *** had positive correlations with annual total precipitation in central south and north *** abnormal climate conditions in 2001 and 2009 caused forest LAI to be obviously lower than normal in regions south of the Qinling Mountains and Huaihe *** mean LAI decreased by more than 1.0 in some areas.

关键词：中国西南部 LAI 时间变化森林空间中国东北地区年平均气温叶面积指数

Among Ethnic People:A Journalist Recalls

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Women of China 1996年第3期 47-49页

作者： chenG jingming chen SHANSHAN

cheng jingming was a journalist for half a century. She participated in the War of Resistance Against Japan and China’s War of Liberation. After the founding of New China,

关键词： Among Ethnic People:A Journalist Recalls

Light Use Efficiency Model Based on Chlorophyll Content Better Captures Seasonal Gross Primary Production Dynamics of Deciduous Broadleaf Forests

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Chinese Geographical Science 2024年

作者： YANG Rongjuan LIU Ronggao LIU Yang chen jingming XU Mingzhu HE Jiaying State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Humid Subtropical Ecogeographical Processes of the Ministry of Education School of Geographical SciencesFujian Normal University Department of Geography and Planning University of Toronto

Gross primary production（GPP） is a crucial indicator representing the absorption of atmospheric CO2by vegetation. At present, the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical parameter leaf area index（LAI）, which are not completely synchronized in seasonality with GPP. In this study, we proposed chlorophyll content-based light use efficiency model（CC-LUE） to improve GPP estimates, as chlorophyll is the direct site of photosynthesis, and only the light absorbed by chlorophyll is used in the photosynthetic process. The CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content(Chlcanopy) and FPAR. This method was calibrated and validated utilizing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five different climate zones. Results showed a relatively robust seasonal consistency between Chlcanopywith GPP in deciduous broadleaf forests under different climatic conditions. The CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and56.0% of in-situ GPP variations through the growing season, outperforming the three widely used LUE models(MODIS-GPP algorithm,Vegetation Photosynthesis Model（VPM）, and the eddy covariance-light use efficiency model（EC-LUE）). Additionally, the CC-LUE model(RMSE = 0.50 g C/（m2·d）) significantly improved the underestimation of GPP during the growing season in semi-arid region, remarkably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%, 73.4%, and37.5%, compared with MOD17(RMSE = 2.03 g C/（m2·d）), VPM(RMSE = 1.88 g C/（m2·d）), and EC-LUE(RMSE = 0.80 g C/（m2·d）)model. The chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems, thereby providing the possibility of a more precise depiction of forest seasonal car

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Mineralization of sediment-hosted ore deposits in reef-chert suite in China

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Chinese Science Bulletin 1999年第S2期44卷 271-272页

作者： chen Duofu, chen Xiangpei, GAO Jiyuan, PAN jingming and chen Guangqian Guangzbou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

THE reef-chert suite, named by chen, mainly consists of four types of rocks, with reef carbonate in thelower part, fine detrital rocks in the upper part, chert beds with ore bodies in the intermediate, and synchronous volcanic rocks either in this sequence or in the same sequence in the neighboring district. It isformed as a fixed and ordered suite in space and time, and is the comprehensive product of normal sedimentary process, biological process in extensional basin, hydrothermal sedimentary process near basinbase and magmatic process in the deep of lithosphere in the special geological setting. Many of thesediment-hosted ore deposits usually occur in such a suite in China, such as Dajiangping pyrite deposit,Shuikoushan lead-zinc ore deposit, Changkeng gold-silver deposit, Dachang cassiterite-lead-zinc ore deposit, Xikuangshan stibium ore deposit, Changba-Lijiangou lead-zinc ore deposit, Baiyunebo

关键词： sediment-hosted deposits reef-chert suite China.

Brillouin Klein space and half-turn space in three-dimensional acoustic crystals

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Science Bulletin 2024年第13期69卷 2050-2058页

作者： Zhenxiao Zhu Linyun Yang Jien Wu Yan Meng Xiang Xi Bei Yan jingming chen Jiuyang Lu Xueqin Huang Weiyin Deng Ce Shang Perry Ping Shum Yihao Yang Hongsheng chen Kexin Xiang Gui-Geng Liu Zhengyou Liu Zhen Gao State Key Laboratory of Optical Fiber and Cable Manufacture Technology Department of Electronic and Electrical EngineeringSouthern University of Science and TechnologyShenzhen 518055China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China Key Laboratory of Artificial Micro-and Nanostructures of Ministry of Education and School of Physics and Technology Wuhan UniversityWuhan 430072China King Abdullah University of Science and Technology(KAUST) Physical Science and Engineering Division(PSE)Thuwal 23955-6900Saudi Arabia Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical InstrumentationZJU-Hangzhou Global Science and Technology Innovation CenterCollege of Information Science and Electronic EngineeringZJU-UIUC InstituteZhejiang UniversityHangzhou 310027China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Institute for Advanced Studies Wuhan UniversityWuhan 430072China

The Bloch band theory and Brillouin zone(BZ)that characterize wave-like behaviors in periodic mediums are two cornerstones of contemporary physics,ranging from condensed matter to topological *** theoretical breakthrough revealed that,under the projective symmetry algebra enforced by artificial gauge fields,the usual two-dimensional(2D)BZ(orientable Brillouin two-torus)can be fundamentally modified to a non-orientable Brillouin Klein bottle with radically distinct manifold ***,the physical consequence of artificial gauge fields on the more general three-dimensional(3D)BZ(orientable Brillouin three-torus)was so far ***,we theoretically discovered and experimentally observed that the fundamental domain and topology of the usual 3D BZ can be reduced to a non-orientable Brillouin Klein space or an orientable Brillouin half-turn space in a 3D acoustic crystal with artificial gauge *** experimentally identify peculiar 3D momentum-space non-symmorphic screw rotation and glide reflection symmetries in the measured band ***,we experimentally demonstrate a novel stacked weak Klein bottle insulator featuring a nonzero Z2 topological invariant and self-collimated topological surface states at two opposite surfaces related by a nonlocal twist,radically distinct from all previous 3D topological *** discovery not only fundamentally modifies the fundamental domain and topology of 3D BZ,but also opens the door towards a wealth of previously overlooked momentum-space multidimensional manifold topologies and novel gaugesymmetry-enriched topological physics and robust acoustic wave manipulations beyond the existing paradigms.

关键词： Momentum-space non-symmorphic symmetry Brillouin Klein space and half-turn space Acoustic Klein bottle insulator Self-collimated topological surface states

InGaAs/GaAs/InGaP Strained Quantum Well Lasers Grown by Metalorganic Chemical Vapor Deposition

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Journal of Semiconductors 1998年第7期 69-72页

作者： Yang Guowen Xu Zuntu Ma Xiaoyu Xu Junying Zhang jingming chen Lianghui (Institute of Semiconductors, The Chinese Academy of Sciences, Beijing 100083)

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｒａｉｎｅｄＩｎＧａＡｓ／ＧａＡｓｑｕａｎｔｕｍｗｅｌ（ＱＷ）ｌａｓｅｒｓｗｉｔｈｅｍｉｓｉｏｎｗａｖｅｌｅｎｇｔｈｏｆ９８０ｎｍａｒｅｃｕｒｅｎｔｌｙｒｅｃｅｉｖｉｎｇｃｏｎｓｉｄｅｒ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｒａｉｎｅｄＩｎＧａＡｓ／ＧａＡｓｑｕａｎｔｕｍｗｅｌ（ＱＷ）ｌａｓｅｒｓｗｉｔｈｅｍｉｓｉｏｎｗａｖｅｌｅｎｇｔｈｏｆ９８０ｎｍａｒｅｃｕｒｅｎｔｌｙｒｅｃｅｉｖｉｎｇｃｏｎｓｉｄｅｒａｂｌｅａｔｅｎｔｉｏｎｂｅｃａｕ...

关键词： InGaAs/GaAs/InGaP Strained Quantum Well Metalorganic Chemical Deposition

Deforestation in Latin America in the 2000s predominantly occurred outside of typical mature forests

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The Innovation 2024年第3期5卷 88-98页

作者： Zhiyu Zhang Wenjian Ni Shaun Quegan jingming chen Peng Gong Luiz Carlos Estraviz Rodriguez Huadong Guo Jiancheng Shi Liangyun Liu Zengyuan Li Yating He Qinhuo Liu Yosio Shimabukuro Guoqing Sun Key Laboratory of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China Chinal of Mathematics and Statistics University of SheffieldSheffield S37RHUK Department of Geography and Program in Planning University of TorontoTorontoON M5S 3G3Canada Department of Earth Sciences and Department of Geography University of Hong KongHong KongChina Forest Science Department Luiz de Queiroz College of AgricultureUniversity of São PauloAv.Pádua Dias11Piracicaba 13418-900Brazil National Space Science Center Chinese Academy of SciencesBeijing 100190China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China Research Institute of Forest Policy and Information Chinese Academy of ForestryBeijing 100091China Remote Sensing Department National Institute for Space Research(INPE)Av.dos Astronautas 1758São Josédos Campos 12227-010Brazil Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA

The role of tropical forests in the global carbon budget remains controversial,as carbon emissions from deforestation are highly *** high uncertainty arises from the use of either fixed forest carbon stock density or maps generated from satellite-based optical reflectance with limited sensitivity to biomass to generate accurate estimates of emissions from *** space missions aiming to accurately map the carbon stock density rely on direct measurements of the spatial structures of forests using lidar and *** found that lost forests are special cases,and their spatial structures can be directly measured by combining archived data acquired before and after deforestation by space missions principally aimed at measuring ***,using biomass mapping,we obtained new estimates of carbon loss from deforestation ahead of forthcoming space ***,using a high-resolution map of forest loss and the synergy of radar and lidar to estimate the aboveground biomass density of forests,we found that deforestation in the 2000s in Latin America,one of the severely deforested regions,mainly occurred in forests with a significantly lower carbon stock density than typical mature forests.

关键词： forest Latin lidar