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Treatment of discontinuities inside Earth models:Effects on computed coseismic deformations 被引量:4
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作者 Jie Dong Gabriele Cambiotti +2 位作者 HanJiang Wen Roberto Sabadini WenKe Sun 《Earth and Planetary Physics》 CSCD 2021年第1期90-104,共15页
In this paper,we study how coseismic deformations calculated in 1066 Earth models are affected by how the models treat Earth discontinuities.From the results of applying models 1066A(continuous)and 1066B(discontinuous... In this paper,we study how coseismic deformations calculated in 1066 Earth models are affected by how the models treat Earth discontinuities.From the results of applying models 1066A(continuous)and 1066B(discontinuous),we find that the difference in Love numbers of strike-slip and horizontal tensile sources are bigger than dip-slip and vertical tensile sources.Taken collectively,discontinuities have major effects on Green’s functions of four independent sources.For the near-field coseismic deformations of the 2013 Okhotsk earthquake(Mw 8.3),the overall differences between theoretical calculations in vertical displacement,geoid,and gravity changes caused by discontinuities are 10.52 percent,9.07 percent and 6.19 percent,with RMS errors of 0.624 mm,0.029 mm,and 0.063μGal,respectively.The difference in far-field displacements is small,compared with GPS data,and we can neglect this effect.For the shallow earthquake,2011 Tohoku-Oki earthquake(Mw 9.0),the differences in near-field displacements are 0.030 m(N-S),0.093 m(E-W),and 0.025 m(up-down)in our study area with the ARIA slip model,which gives results closer to GPS data than those from the USGS model.The difference in vertical displacements and gravity changes on the Earth’s surface caused by discontinuities are larger than 10 percent.The difference in the theoretical gravity changes at spatially fixed points truncated to degrees 60,as required by GRACE data,is 0.0016μGal and the discrepancy is 11 percent,with the theoretical spatial gravity changes from 1066B closer to observations than from 1066A.The results show that an Earth model with discontinuities in the medium has a large effect on the calculated coseismic deformations. 展开更多
关键词 DISCONTINUITIES earth model coseismic deformations GPS GRACE
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A Novel Method for Locally Updating an Earth Model While Geosteering 被引量:1
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作者 Erich Suter Eric Cayeux +3 位作者 Helmer A.Friis Terje Karstad Alejandro Escalona Erlend Vefring 《International Journal of Geosciences》 2017年第2期237-264,共28页
Earth models are important tools for support of decision making processes for optimal exploitation of subsurface resources. For geosteering and other real-time processes where time is a major constraint, effective mod... Earth models are important tools for support of decision making processes for optimal exploitation of subsurface resources. For geosteering and other real-time processes where time is a major constraint, effective model management is decisive for optimal decision support. During drilling, subsurface information is received which should optimally be used to modify the 3D earth model. Today this model is typically not altered during the operation. We discuss the principles of a novel method that enables a populated earth model grid to be locally modified when the topology (connectivity) of the geological structure is locally altered. The method also allows local updates of the grid resolution. The modelled volume is split into closed regions by the structural model. Each region is individually discretized and obtains its own subgrid. Properties are stored in separate functions, e.g. for each layer, and transferred into each subgrid via a mapping. A local update of the geological structure implies that only subgrids in regions that are directly affected by the updated structure must be discarded and rebuilt, and the rest of the populated earth model grid is retained. Our focus is on decision support for optimal well placement while geosteering. The proposed method aims to manage multiple model realizations that are never fixed and always locally updated with the most recent measurements and interpretations in real-time, and where each realization is always kept at an optimal resolution. 展开更多
关键词 GEOSTEERING Optimal Well Placement earth modelling Local Update Geological Structure CONNECTIVITY Uncertainty
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STUDIES ON POLYMERIZATION MECHANISM OF CONJUGATED DIENE WITH η~3-ALLYL RARE EARTH MODEL COMPLEX
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作者 Feng Fu LI Ying Tai JIN Feng Kui PEI Fo Song WANG Changchun Institute of Applied Chemistry,Academia Sinica.Changchun,130022Wen Ling Wu Department of Chemistry,Fudan University,Shanghai 200433 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期281-282,共2页
(η^-C_H_5)_2CeCl_5Mg_2(tmed)_2 was used as a catalyst to polymerize isoprene,Terminal ends of polyisoprene were identified as -CH_2-CH=CH_,which indicates that the insertion reaction of the monomer occurred between ... (η^-C_H_5)_2CeCl_5Mg_2(tmed)_2 was used as a catalyst to polymerize isoprene,Terminal ends of polyisoprene were identified as -CH_2-CH=CH_,which indicates that the insertion reaction of the monomer occurred between η^-allyl and cerium ion and gives a direct evidence for the η^-allyl mechanism of conjugated diene polymerzation with rare earth coordination catalysts. 展开更多
关键词 POLY ALLYL RARE earth model COMPLEX STUDIES ON POLYMERIZATION MECHANISM OF CONJUGATED DIENE WITH
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Global SH-wavefield calculation for a two-dimensional whole-Earth model with the parallel hybrid PSM/FDM algorithm
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作者 Yanbin Wang Yang Luo +1 位作者 Yanfang Qin Xianbing Zhang 《Earthquake Science》 2014年第3期277-284,共8页
We present a parallel hybrid algorithm based on pseudospectral method (PSM) and finite difference method (FDM) for two-dimensional (2-D) global SH- wavefield simulation. The whole-Earth model is taken as a cross... We present a parallel hybrid algorithm based on pseudospectral method (PSM) and finite difference method (FDM) for two-dimensional (2-D) global SH- wavefield simulation. The whole-Earth model is taken as a cross section of spherical Earth, and corresponding wave equations are defined in 2-D cylindrical coordinates. Spatial derivatives in the wave equations are approximated with efficient and high accuracy PSM in the lateral and high-order FDM in the radial direction on staggered grids. This algorithm allows us to divide the whole-Earth into sub-domains in radial direction and implement efficient parallel computing on PC cluster, while retains high accuracy and efficiency of PSM in lateral direction. A transformation of moment tensor between 3-D spherical Earth and our 2-D model was proposed to give corre- sponding moment tensor components used in 2-D modeling. Comparison of modeling results with those obtained by direct solution method shows very good accuracy of our algorithm. We also demonstrate its feasibility with a lateral heterogeneous whole-Earth model with localized velocity perturbation. 展开更多
关键词 SH-wave propagation Whole-earth -Numerical modeling Hybrid method Parallel computing
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Characterization and Modeling of Reinforced Earth Structures
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作者 Tchamiè David Midikizi Oustasse Abdoulaye Sall +3 位作者 Déthié Sarr Cheikh Ibrahima Tine Ndeye Seynabou Ndiaye Makhaly Ba 《Open Journal of Applied Sciences》 2024年第10期2943-2954,共12页
The aim of this study is to characterize soil/reinforcement interaction in reinforced earth structures. The study showed that the internal behavior of this type of structure depends on a number of factors, including t... The aim of this study is to characterize soil/reinforcement interaction in reinforced earth structures. The study showed that the internal behavior of this type of structure depends on a number of factors, including the engineering backfill, the reinforcement and the soil/reinforcement interaction. The study also showed that the soil-reinforcement interaction phenomenon is a fairly complex mechanism that depends on the applied load, the geometry of the structure, the characteristics of the soil and a set of parameters characterizing the nailing: density, number and length of reinforcements, inclination of the reinforcements in relation to the sliding surface, mechanical characteristics of the reinforcements and, in particular, the relative stiffness of the reinforcements and the soil. The results showed that the tensile forces developed in the reinforcement are not entirely reversible, and that the soil at the interface undergoes permanent deformation, leading to the appearance of irreversible tensile forces in the reinforcement. 展开更多
关键词 Reinforced earth Structures modelING earth/Reinforcement Interaction
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Coupling of the Calculated Freezing and Thawing Front Parameterization in the Earth System Model CAS-ESM 被引量:3
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作者 Ruichao LI Jinbo XIE +5 位作者 Zhenghui XIE Binghao JIA Junqiang GAO Peihua QIN Longhuan WANG Si CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第9期1671-1688,共18页
The soil freezing and thawing process affects soil physical properties,such as heat conductivity,heat capacity,and hydraulic conductivity in frozen ground regions,and further affects the processes of soil energy,hydro... The soil freezing and thawing process affects soil physical properties,such as heat conductivity,heat capacity,and hydraulic conductivity in frozen ground regions,and further affects the processes of soil energy,hydrology,and carbon and nitrogen cycles.In this study,the calculation of freezing and thawing front parameterization was implemented into the earth system model of the Chinese Academy of Sciences(CAS-ESM)and its land component,the Common Land Model(CoLM),to investigate the dynamic change of freezing and thawing fronts and their effects.Our results showed that the developed models could reproduce the soil freezing and thawing process and the dynamic change of freezing and thawing fronts.The regionally averaged value of active layer thickness in the permafrost regions was 1.92 m,and the regionally averaged trend value was 0.35 cm yr–1.The regionally averaged value of maximum freezing depth in the seasonally frozen ground regions was 2.15 m,and the regionally averaged trend value was–0.48 cm yr–1.The active layer thickness increased while the maximum freezing depth decreased year by year.These results contribute to a better understanding of the freezing and thawing cycle process. 展开更多
关键词 frozen ground freezing and thawing fronts maximum freezing depth active layer thickness earth system model CAS-ESM
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Spatial Inhomogeneity of Atmospheric CO_(2) Concentration and Its Uncertainty in CMIP6 Earth System Models
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作者 Chengjun XIE Tongwen WU +7 位作者 Jie ZHANG Kalli FURTADO Yumeng ZHOU Yanwu ZHANG Fanghua WU Weihua JIE He ZHAO Mengzhe ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期2108-2126,共19页
This paper provides a systematic evaluation of the ability of 12 Earth System Models(ESMs)participating in the Coupled Model Intercomparison Project Phase 6(CMIP6)to simulate the spatial inhomogeneity of the atmospher... This paper provides a systematic evaluation of the ability of 12 Earth System Models(ESMs)participating in the Coupled Model Intercomparison Project Phase 6(CMIP6)to simulate the spatial inhomogeneity of the atmospheric carbon dioxide(CO_(2))concentration.The multi-model ensemble mean(MME)can reasonably simulate the increasing trend of CO_(2) concentration from 1850 to 2014,compared with the observation data from the Scripps CO_(2) Program and CMIP6 prescribed data,and improves upon the CMIP5 MME CO_(2) concentration(which is overestimated after 1950).The growth rate of CO_(2) concentration in the northern hemisphere(NH)is higher than that in the southern hemisphere(SH),with the highest growth rate in the mid-latitudes of the NH.The MME can also reasonably simulate the seasonal amplitude of CO_(2) concentration,which is larger in the NH than in the SH and grows in amplitude after the 1950s(especially in the NH).Although the results of the MME are reasonable,there is a large spread among ESMs,and the difference between the ESMs increases with time.The MME results show that regions with relatively large CO_(2) concentrations(such as northern Russia,eastern China,Southeast Asia,the eastern United States,northern South America,and southern Africa)have greater seasonal variability and also exhibit a larger inter-model spread.Compared with CMIP5,the CMIP6 MME simulates an average spatial distribution of CO_(2) concentration that is much closer to the site observations,but the CMIP6-inter-model spread is larger.The inter-model differences of the annual means and seasonal cycles of atmospheric CO_(2) concentration are both attributed to the differences in natural sources and sinks of CO_(2) between the simulations. 展开更多
关键词 CMIP6 earth System models the simulation of atmospheric CO_(2)concentration spatial inhomogeneity UNCERTAINTY
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Investigating the effect of the Tibetan Plateau on the ITCZ using a coupled Earth system model
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作者 Chuqiao Yan Jie Yao +1 位作者 Xingchen Shen Haijun Yang 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第1期53-58,共6页
本文利用耦合地球气候系统模式研究了青藏高原对热带辐合带(ITCZ)的影响.我们研究发现热带大西洋ITCZ的位置对青藏高原存在与否有明显的敏感性.与目前真实情况相比,移除青藏高原会导致北半球海面降温,南半球海面升温.这种海面温度变化... 本文利用耦合地球气候系统模式研究了青藏高原对热带辐合带(ITCZ)的影响.我们研究发现热带大西洋ITCZ的位置对青藏高原存在与否有明显的敏感性.与目前真实情况相比,移除青藏高原会导致北半球海面降温,南半球海面升温.这种海面温度变化在大西洋表现得尤为明显,导致热带大西洋最大海温中心向南移动,从而迫使大气对流中心向南移动,即表现为ITCZ的南移.相应地,夏季热带大气Hadley环流的上升支也发生明显南移.北(南)半球海洋变冷(变暖)这种态势要求增强跨赤道向北的大气经向热量输送,从而维持各个半球的能量平衡,而这需要ITCZ位置的南移才能实现.本文研究表明,青藏高原的存在在现今ITCZ气候态的形成中可能扮演了重要角色. 展开更多
关键词 青藏高原 热带辐合带 耦合地球气候模式 HADLEY环流 热量输送
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Using EARTH Model to Estimate Groundwater Recharge at Five Representative Zones in the Hebei Plain, China 被引量:2
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作者 Bingguo Wang Menggui Jin Xing Liang 《Journal of Earth Science》 SCIE CAS CSCD 2015年第3期425-434,共10页
Accurate estimation of groundwater recharge is essential for efficient and sustainable groundwater management in many semi-arid regions. In this paper, a lumped parameter model(EARTH) was established to simulate the... Accurate estimation of groundwater recharge is essential for efficient and sustainable groundwater management in many semi-arid regions. In this paper, a lumped parameter model(EARTH) was established to simulate the recharge rate and recharge process in typical areas by the observation datum of weather, soil water and groundwater synthetically, and the spatial and temporal variation law of groundwater recharge in the Hebei Plain was revealed. The mean annual recharge rates at LQ, LC, HS, DZ and CZ representative zones are 220.1, 196.7, 34.1, 141.0 and 188.0 mm/a and the recharge coefficients are 26.5%, 22.3%, 7.2%, 20.4%, and 22.0%, respectively. Recharge rate and recharge coefficient are gradually reduced from piedmont plain to coastal plain. Groundwater recharge appears as only yearly waves, with higher frequency components of the input series filtered by the deep complicated unsaturated zone(such as LC). While at other zones, groundwater recharge series strongly dependent on the daily rainfall and irrigation because of the shallow water table or coarse lithology. 展开更多
关键词 earth model groundwater recharge Hebei Plain
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Major Modes of Short-Term Climate Variability in the Newly Developed NUIST Earth System Model(NESM) 被引量:10
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作者 CAO Jian Bin WANG +5 位作者 Baoqiang XIANG Juan LI WU Tianjie Xiouhua FU WU Liguang MIN Jinzhong 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第5期585-600,共16页
A coupled earth system model(ESM) has been developed at the Nanjing University of Information Science and Technology(NUIST) by using version 5.3 of the European Centre Hamburg Model(ECHAM), version 3.4 of the Nu... A coupled earth system model(ESM) has been developed at the Nanjing University of Information Science and Technology(NUIST) by using version 5.3 of the European Centre Hamburg Model(ECHAM), version 3.4 of the Nucleus for European Modelling of the Ocean(NEMO), and version 4.1 of the Los Alamos sea ice model(CICE). The model is referred to as NUIST ESM1(NESM1). Comprehensive and quantitative metrics are used to assess the model's major modes of climate variability most relevant to subseasonal-to-interannual climate prediction. The model's assessment is placed in a multi-model framework. The model yields a realistic annual mean and annual cycle of equatorial SST, and a reasonably realistic precipitation climatology, but has difficulty in capturing the spring–fall asymmetry and monsoon precipitation domains. The ENSO mode is reproduced well with respect to its spatial structure, power spectrum, phase locking to the annual cycle, and spatial structures of the central Pacific(CP)-ENSO and eastern Pacific(EP)-ENSO; however, the equatorial SST variability,biennial component of ENSO, and the amplitude of CP-ENSO are overestimated. The model captures realistic intraseasonal variability patterns, the vertical-zonal structures of the first two leading predictable modes of Madden–Julian Oscillation(MJO), and its eastward propagation; but the simulated MJO speed is significantly slower than observed. Compared with the T42 version, the high resolution version(T159) demonstrates improved simulation with respect to the climatology, interannual variance, monsoon–ENSO lead–lag correlation, spatial structures of the leading mode of the Asian–Australian monsoon rainfall variability, and the eastward propagation of the MJO. 展开更多
关键词 coupled climate model earth system model climate variability
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Global Climate Internal Variability in a 2000-year Control Simulation with Community Earth System Model(CESM) 被引量:13
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作者 WANG Zhiyuan LI Yao +1 位作者 LIU Bin LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2015年第3期263-273,共11页
Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation ... Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation was carried out with fixed external forcing factors (1850 Common Era. (C.E.) conditions) for the past 2000 years. Based on the simulated results, spatio-temporal structures of surface air temperature, precipitation and internal variability, such as the E1 Nifio-Southem Oscillation (ENSO), the Atlantic Multi-decadal Oscilla- tion (AMO), the Pacific Decadal Oscillation (PDO), and the North Atlantic Oscillation (NAO), were compared with reanalysis datasets to evaluate the model performance. The results are as follows: 1) CESM showed a good performance in the long-term simulation and no significant climate drift over the past 2000 years; 2) climatological patterns of global and regional climate changes simulated by the CESM were reasonable compared with the reanalysis datasets; and 3) the CESM simulated internal natural variability of the climate system performs very well. The model not only reproduced the periodicity of ENSO, AMO and PDO events but also the 3-8 years vari- ability of the ENSO. The spatial distribution of the CESM-simulated NAO was also similar to the observed. However, because of weaker total irradiation and greenhouse gas concentration forcing in the simulation than the present, the model performances had some differences from the observations. Generally, the CESM showed a good performance in simulating the global climate and internal natu- ral variability of the climate system. This paves the way for other forced climate simulations for the past 2000 years by using the CESM. 展开更多
关键词 Community earth System model (CESM) climate simulation past 2000 years climate system intemal variability
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Regional earth system modeling:review and future directions 被引量:4
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作者 Filippo GIORGI GAO Xue-Jie 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第2期189-197,共9页
The authors review recent advances in the development of coupled Regional Earth System Models (RESMs),a field that is still in its early stages.To date,coupled regional atmosphere-ocean-sea ice,atmosphere-aerosol an... The authors review recent advances in the development of coupled Regional Earth System Models (RESMs),a field that is still in its early stages.To date,coupled regional atmosphere-ocean-sea ice,atmosphere-aerosol and atmosphere-biosphere models have been developed,but they have been applied onlyto limited regional settings.Much more work is thus needed to assess their transferability to a wide range of settings.Future challenges in regional climate modeling are identified,including the development of fully coupled RESMs encompassing not only atmosphere,ocean,cryosphere,biosphere,chemosphere,but also the human component in a fully interactive way. 展开更多
关键词 Regional climate model regional earth system model atmosphere-ocean coupling atmosphere-aerosolcoupling
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Quantifying the impacts of fire aerosols on global terrestrial ecosystem productivity with the fully-coupled Earth system model CESM 被引量:2
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作者 LI Fang 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期330-337,共8页
Fire is a global phenomenon and a major source of aerosols from the terrestrial biosphere to the atmosphere.Most previous studies quantified the effect of fire aerosols on climate and atmospheric circulation,or on the... Fire is a global phenomenon and a major source of aerosols from the terrestrial biosphere to the atmosphere.Most previous studies quantified the effect of fire aerosols on climate and atmospheric circulation,or on the regional and site-scale terrestrial ecosystem productivity.So far,only one work has quantified their global impacts on terrestrial ecosystem productivity based on offline simulations,which,however,did not consider the impacts of aerosol–cloud interactions and aerosol–climate feedbacks.This study quantitatively assesses the influence of fire aerosols on the global annual gross primary productivity(GPP)of terrestrial ecosystems using simulations with the fully coupled global Earth system model CESM1.2.Results show that fire aerosols generally decrease GPP in vegetated areas,with a global total of−1.6 Pg C yr^−1,mainly because fire aerosols cool and dry the land surface and weaken the direct photosynthetically active radiation(PAR).The exception to this is the Amazon region,which is mainly due to a fire-aerosol-induced wetter land surface and increased diffuse PAR.This study emphasizes the importance of the influence of fire aerosols on climate in quantifying global-scale fire aerosols’impacts on terrestrial ecosystem productivity. 展开更多
关键词 Fire aerosols terrestrial ecosystem gross primary productivity land–atmosphere interaction earth system model
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Earth System Model FGOALS-s2: Coupling a Dynamic Global Vegetation and Terrestrial Carbon Model with the Physical Climate System Model 被引量:1
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作者 王军 包庆 +3 位作者 Ning ZENG 刘屹岷 吴国雄 纪多颖 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第6期1549-1559,共11页
Earth System Models (ESMs) are fundamental tools for understanding climate-carbon feedback. An ESM version of the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) was recently developed within the IPCC ... Earth System Models (ESMs) are fundamental tools for understanding climate-carbon feedback. An ESM version of the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) was recently developed within the IPCC AR5 Coupled Model Intercomparison Project Phase 5 (CMIP5) modeling framework, and we describe the development of this model through the coupling of a dynamic global vegetation and terrestrial carbon model with FGOALS-s2. The performance of the coupled model is evaluated as follows. The simulated global total terrestrial gross primary production (GPP) is 124.4 PgC yr-I and net pri- mary production (NPP) is 50.9 PgC yr-1. The entire terrestrial carbon pools contain about 2009.9 PgC, comprising 628.2 PgC and 1381.6 PgC in vegetation and soil pools, respectively. Spatially, in the tropics, the seasonal cycle of NPP and net ecosystem production (NEP) exhibits a dipole mode across the equator due to migration of the monsoon rainbelt, while the seasonal cycle is not so significant in Leaf Area Index (LAI). In the subtropics, especially in the East Asian monsoon region, the seasonal cycle is obvious due to changes in temperature and precipitation from boreal winter to summer. Vegetation productivity in the northern mid-high latitudes is too low, possibly due to low soil moisture there. On the interannual timescale, the terrestrial ecosystem shows a strong response to ENSO. The model- simulated Nifio3.4 index and total terrestrial NEP are both characterized by a broad spectral peak in the range of 2-7 years. Further analysis indicates their correlation coefficient reaches -0.7 when NEP lags the Nifio3.4 index for about 1-2 months. 展开更多
关键词 earth System model (ESM) Dynamic Global Vegetation model (DGVM) carbon cycle sea- sonal cycle interannual variability
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Global air-sea CO_(2) exchange fl ux since 1980s: results from CMIP6 Earth System Models 被引量:1
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作者 Baoxiao QU Jinming SONG +3 位作者 Xuegang LI Huamao YUAN Kun ZHANG Suqing XU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1417-1436,共20页
The ocean could profoundly modulate the ever-increasing atmospheric CO_(2) by air-sea CO_(2) exchange process,which is also able to cause signifi cant changes of physical and biogeochemical properties in return.In thi... The ocean could profoundly modulate the ever-increasing atmospheric CO_(2) by air-sea CO_(2) exchange process,which is also able to cause signifi cant changes of physical and biogeochemical properties in return.In this study,we assessed the long-term average and spatial-temporal variability of global air-sea CO_(2) exchange fl ux(F CO_(2))since 1980s basing on the results of 18 Coupled Model Intercomparison Project Phase 6(CMIP6)Earth System Models(ESMs).Our fi ndings indicate that the CMIP6 ESMs simulated global CO_(2) sink in recent three decades ranges from 1.80 to 2.24 Pg C/a,which is coincidence with the results of cotemporaneous observations.What’s more,the CMIP6 ESMs consistently show that the global oceanic CO_(2) sink has gradually intensifi ed since 1980s as well as the observations.This study confi rms the simulated F CO_(2) could reach agreements with the observations in the aspect of primary climatological characteristics,however,the simulation skills of CIMP6 ESMs in diverse open-sea biomes are unevenness.None of the 18 CMIP6 ESMs could reproduce the observed F CO_(2) increasement in the central-eastern tropical Pacifi c and the midlatitude Southern Ocean.Defi ciencies of some CMIP6 ESMs in reproducing the atmospheric pressure systems of the Southern Hemisphere and the El Niño-Southern Oscillation(ENSO)mode of the tropical Pacifi c are probably the major causes. 展开更多
关键词 air-sea CO_(2)fl ux Coupled model Intercomparison Project Phase 6(CMIP6) earth System model(ESM) long-term average spatial-temporal variability
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Simulations of dissolved oxygen concentration in CMIP5 Earth system models
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作者 BAO Ying LI Yangchun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第12期28-37,共10页
The climatologies of dissolved oxygen concentration in the ocean simulated by nine Earth system models(ESMs) from the historical emission driven experiment of CMIP5(Phase 5 of the Climate Model Intercomparison Project... The climatologies of dissolved oxygen concentration in the ocean simulated by nine Earth system models(ESMs) from the historical emission driven experiment of CMIP5(Phase 5 of the Climate Model Intercomparison Project) are quantitatively evaluated by comparing the simulated oxygen to the WOA09 observation based on common statistical metrics. At the sea surface, distribution of dissolved oxygen is well simulated by all nine ESMs due to well-simulated sea surface temperature(SST), with both globally-averaged error and root mean square error(RMSE) close to zero, and both correlation coefficients and normalized standard deviation close to 1. However, the model performance differs from each other at the intermediate depth and deep ocean where important water masses exist. At the depth of 500 to 1 000 m where the oxygen minimum zones(OMZs) exist, all ESMs show a maximum of globally-averaged error and RMSE, and a minimum of the spatial correlation coefficient. In the ocean interior, the reason for model biases is complicated, and both the meridional overturning circulation(MOC) and the particulate organic carbon flux contribute to the biases of dissolved oxygen distribution. Analysis results show the physical bias contributes more. Simulation bias of important water masses such as North Atlantic Deep Water(NADW), Antarctic Bottom Water(AABW) and North Pacific Intermediate Water(NPIW) indicated by distributions of MOCs greatly affects the distributions of oxygen in north Atlantic, Southern Ocean and north Pacific, respectively.Although the model simulations of oxygen differ greatly from each other in the ocean interior, the multi-model mean shows a better agreement with the observation. 展开更多
关键词 dissolved oxygen CMIP5 earth system model meridional overturning circulation particulate organic carbon flux
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Study on Spectral Overlap Model for Energy Transfer between J-Multiplets in Rare Earth-Doped Crystals 被引量:1
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作者 王殿元 夏上达 尹民 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第1期13-18,共6页
Based on the experimental data of KY 3F 10∶Tm 3+ reported by Diaf, K ushida′s spectral overlap model (SOM) of energy transfer between J-multipl ets was studied. Firstly, with the help of the Inokuti-Hirayama an... Based on the experimental data of KY 3F 10∶Tm 3+ reported by Diaf, K ushida′s spectral overlap model (SOM) of energy transfer between J-multipl ets was studied. Firstly, with the help of the Inokuti-Hirayama and Yokota-Tan imoto models, the luminescence decay curve of 3H 4 of Tm 3+ ion was fitted, and the fitted values of corresponding interaction parameters C D A of energy transfer and C DD of energy migration were obtained. Seco ndly, by compared with Kushida′s SOM in which the relevant Judd-Ofelt approxim ative transition rates are known, the average overlap integrals of S DD and S DA were obtained. For S DD, how to treat the contributi on of the electronic-dipole (ED) crystal field transition forbidden by C 4v site symmetry in the calculation of S DD was discussed. For S DA we suggested that, by including the contribution of the phonon sideba nds in the analysis of oscillator strength of transition, Kushida′s SOM of ED- ED resonant energy transfer rate can be extended to non-resonant phonon-assist ed D-A energy transfer. The strengths and widths of phonon sidebands in this ex ample were discussed, and the results were reasonably good. 展开更多
关键词 LUMINESCENCE energy transfer energy migrat ion spectral overlap model rare earths
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IGCP 641 Project:Mechanisms,Monitoring and Modeling Earth Fissure Generation and Fault Activation due to Subsurface Fluid Exploitation
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作者 YE Shujun Dora CARREoN-FREYRE +1 位作者 Pietro TEATINI Devin GALLOWAY 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期165-168,共4页
Ground ruptures(fractures,earth fissures and reactivation of pre-existing surface faults)caused by extraction of fluids from the subsurface have been observed in hundreds of sedimentary basins worldwide,mainly in semi... Ground ruptures(fractures,earth fissures and reactivation of pre-existing surface faults)caused by extraction of fluids from the subsurface have been observed in hundreds of sedimentary basins worldwide,mainly in semiarid to arid areas of the USA,Mexico,China,India,Libya,Iran,and Saudi Arabia. 展开更多
关键词 MECHANISMS monitoring modeling earth FISSURE SUBSURFACE FLUID EXPLOITATION
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Modeling the Drying Kinetics of Earth Bricks Stabilized with Cassava Flour Gel and Amylopectin 被引量:1
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作者 Mondésir Ngoulou Raymond Gentil Elenga +2 位作者 Louis Ahouet Stevina Bouyila Serge Konda 《Geomaterials》 2019年第1期40-53,共14页
Earth bricks could contribute to alleviate the housing shortage in the world, thanks to their low cost, easy production, and low environmental impact. However, to manufacture bricks with required properties, many raw ... Earth bricks could contribute to alleviate the housing shortage in the world, thanks to their low cost, easy production, and low environmental impact. However, to manufacture bricks with required properties, many raw soils must be ameliorated. In Central and Eastern Africa, the waste water of the cassava processing is used to improve earth brick mechanical properties. This technique is interesting, because it is sustainable, low-cost and easy to implement. But, studies on this stabilization method are scarce, in particular on the drying kinetics of these bricks. Now, it is important to know the drying duration, because the earth brick’s strength is strongly correlated to its moisture content. Thus, this study aims to quantify and to model the effect of adding cassava flour gel and amylopectin on the drying kinetics of earth bricks. Depending on the soil nature, the drying duration decreases from 7% to 25% for a stabilizer content of 20%. For the five models used, the coefficient of determination is superior to 0.997 and the chi square is inferior to 3 × 10&#8722;4. In average, the best model is Khazaei, followed in order by Avrami-Page, diffusion, Yong and Peleg. The effective coefficient of diffusion of water is about 4 × 10&#8722;5 m&#8901;s&#8722;2. The parameter T of the Khazaei’s model is strongly correlated to the drying duration and the stabilizer content, and their relationships have been deduced. 展开更多
关键词 earth BRICK Stabilization Drying Kinetics modelING CASSAVA Starch
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A Theoretical Model of Energy Transfer between Rare Earth Ions in Crystals
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作者 林炎富 罗遵度 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第8期975-979,共5页
The limitation of the random walk theory of energy transfer between rare earth ions in crystals published in literatures is pointed out in this paper. A modified model, which can be used in any level of rare earth ion... The limitation of the random walk theory of energy transfer between rare earth ions in crystals published in literatures is pointed out in this paper. A modified model, which can be used in any level of rare earth ion concentration when the interaction between donor and acceptor is different from that between donors, is introduced. measured fluorescence lifetimes of Yb^3+:YAl3(BO3)4 This model has been applied to analyze the with a series of Yb^3+ concentrations. 展开更多
关键词 energy transfer rare earth ion theoretical model
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