本文采用基于WRFDA的集合-变分混合同化系统(En3DVAR)在云尺度分辨率下同化了雷达观测资料考察其对登陆台风"桑美"的影响。高时空分辨率的雷达径向风资料在台风登陆前的3h同化窗内以每30min的频率同化进WRF模式(Weather Resea...本文采用基于WRFDA的集合-变分混合同化系统(En3DVAR)在云尺度分辨率下同化了雷达观测资料考察其对登陆台风"桑美"的影响。高时空分辨率的雷达径向风资料在台风登陆前的3h同化窗内以每30min的频率同化进WRF模式(Weather Research and Forecasting)。研究结果表明:En3DVAR试验在3h同化窗内的均方根误差相比3DVAR试验改进显著,这可能得益于混合同化系统中提供的"流依赖"的集合协方差信息。系统性的诊断分析表明En3DVAR试验在台风内核区产生了较为明显正温度增量,对台风内核区的热力和动力结构均有较好调整,而3DVAR则在台风内核区产生了负温度增量;相比3DAVR试验,En3DVAR在采用了"流依赖"的集合协方差信息后还可以对背景场上的台风的位置进行系统性的偏差订正。总体而言,En3DVAR试验预报的台风路径和强度相比3DVAR改进显著,其正效果主要来源于混合背景误差协方差中的"流依赖"集合协方差信息。展开更多
Co(En)\-3MoO\-4 was synthesized by using the method of hydrothermal synthesis and characterized by elemental analysis, IR, ESR and single\|crystal X\|ray methods. It crystallizes in hexagonal space group \%P3C1\% with...Co(En)\-3MoO\-4 was synthesized by using the method of hydrothermal synthesis and characterized by elemental analysis, IR, ESR and single\|crystal X\|ray methods. It crystallizes in hexagonal space group \%P3C1\% with \{\%a\%=1\^596 4(2) nm\}, \{\%b\%=1\^596 4(2) nm\}, \%c\%=\{0\^993 5(2)\} nm, \%α=β\%=90°, \%γ\%=120°, \%M\%\-c=399\^18, \%V\%=2\^192 6(6) nm\+3, \%D\%\-c=1\^814 g/nm\+3, \%Z\%=6, \%F\%(000)=1 218, \%R\%\-1=0\^070 3, \%R\%\-w=0\^220 7. According to separation of anion which acted on electrostatic potential, the anion and cation ions formed a type of organic and inorganic material.展开更多
Land surface models are often highly nonlinear with model physics that contain parameterized discontinuities. These model attributes severely limit the application of advanced variational data assimilation methods int...Land surface models are often highly nonlinear with model physics that contain parameterized discontinuities. These model attributes severely limit the application of advanced variational data assimilation methods into land data assimilation. The ensemble Kalman filter (EnKF) has been widely employed for land data assimilation because of its simple conceptual formulation and relative ease of implementation. An updated ensemble-based three-dimensional variational assimilation (En3-DVar) method is proposed for land data assimilation.This new method incorporates Monte Carlo sampling strategies into the 3-D variational data assimilation framework. The proper orthogonal decomposition (POD) technique is used to efficiently approximate a forecast ensemble produced by the Monte Carlo method in a 3-D space that uses a set of base vectors that span the ensemble. The data assimilation process is thus significantly simplified. Our assimilation experiments indicate that this new En3-DVar method considerably outperforms the EnKF method by increasing assimilation precision. Furthermore, computational costs for the new En3-DVar method are much lower than for the EnKF method.展开更多
A new compound, \[Ni(en)\-3\]\-2\[Ni(en)\-2(H\-2O)\-2\]\[As\-6V\-\{15\}O\-\{42\}\]·4H\-2O, was first prepared by hydrothermal synthesis and characterized by elemental analysis, IR, TGA\|DSC, ESR and single crysta...A new compound, \[Ni(en)\-3\]\-2\[Ni(en)\-2(H\-2O)\-2\]\[As\-6V\-\{15\}O\-\{42\}\]·4H\-2O, was first prepared by hydrothermal synthesis and characterized by elemental analysis, IR, TGA\|DSC, ESR and single crystal X\|ray diffraction. Crystal data: monoclinic, space group \%C\-c, a\%=1\^523 6(3) nm, \%b\%=2\^051 8(4) nm, \%c\%=2\^395 9(5) nm, \%β=97\^41(3)°, V\%=7\^427(3) nm\+3, \%Z=4, R=0\^057 0, wR\-2=0\^135 7\%. The polyanion consists of six AsO\-3 pyramids and fifteen VO\-5 pyramids. Counterions are complex ions with octahedral structure, which consist of NH\-2CH\-2CH\-2NH\-2 and Ni\+\{2+\}.展开更多
Co(en) 3V 3O 6·H 2O has been synthesized by using hydrothermal method and characterized by IR, ICP, XPS and X ray diffraction analysis. The results of the X ray diffraction analysis show that structure of Co(en) ...Co(en) 3V 3O 6·H 2O has been synthesized by using hydrothermal method and characterized by IR, ICP, XPS and X ray diffraction analysis. The results of the X ray diffraction analysis show that structure of Co(en) 3(VO 3) 3·H 2O is orthorhombic with P2(1)2(1)2(1) , and the crystal data are a =0 819 2(7) nm, b =1.263 9(1) nm, c =1.804 8(2) nm, V =1.868 8(3) nm 3, Z=4, D c=1.973 g/cm 3, F (000)=1 124, R 1=0.040 7, wR 2=0.094 9, ( Δ/ρ ) max =706 e/nm 3 and ( Δ/ρ ) min =-452 e/nm 3. The results of XPS show that the Co 2+ was oxidized to Co 3+ (en) 3 at about pH=7.0 in the aqueous solution.展开更多
In this study the steric height anomaly which is calculated from the hydrological data （EN3） is compared with the sea level anomaly derived from satellite altimetry in the Nordic Seas. The overall pattern of steric ...In this study the steric height anomaly which is calculated from the hydrological data （EN3） is compared with the sea level anomaly derived from satellite altimetry in the Nordic Seas. The overall pattern of steric height is that it is higher in the margin area and lower in the middle area. The extreme values of steric height linear change from 1993 to 2010 occur in the Lofoten Basin and off the Norwegian coast, respectively. Such a distribution may be partly attributed to the freshening trend of the Nordic Seas. The correlation between SLA （sea level anomaly） and SHA （steric height anomaly） is not uniform over the Nordic Seas. The time series of SLA and SHA agree well in the Lofoten Basin and northern Norwegian Basin, and worse in the northern Norwegian Sea, implying that the baroclinic effect plays a dominant role in most areas in the Norwegian Sea and the barotropic effect plays a dominant role in the northern Norwegian Sea. The weaker correlations between SLA and SHA in the Greenland and Iceland Seas lead a conclusion that the barotropic contribution is significant in these areas. The area-mean SHA over the entire Nordic Seas has similar amplitudes compared with the SLA during 1996-2002, but SHA has become lower than SLA, being less than half of SLA since 2006.展开更多
El Nio events in the central equatorial Pacific (CP) are gaining increased attention,due to their increasing intensity within the global warming context.Various physical processes have been identified in the climate s...El Nio events in the central equatorial Pacific (CP) are gaining increased attention,due to their increasing intensity within the global warming context.Various physical processes have been identified in the climate system that can be responsible for the modulation of El Nio,especially the effects of interannual salinity variability.In this work,a comprehensive data analysis is performed to illustrate the effects of interannual salinity variability using surface and subsurface salinity fields from the Met Office ENSEMBLES (EN3) quality controlled ocean dataset.It is demonstrated that during the developing phase of an El Nio event,a negative sea surface salinity (SSS) anomaly in the western-central basin acts to freshen the mixed layer (ML),decrease oceanic density in the upper ocean,and stabilize the upper layers.These related oceanic processes tend to reduce the vertical mixing and entrainment of subsurface water at the base of the ML,which further enhances the warm sea surface temperature (SST) anomalies associated with the El Nio event.However,the effects of interannually variable salinity are much more significant during the CP-El Nio than during the eastern Pacific (EP) El Nio,indicating that the salinity effect might be an important contributor to the development of CP-El Nio events.展开更多
文摘本文采用基于WRFDA的集合-变分混合同化系统(En3DVAR)在云尺度分辨率下同化了雷达观测资料考察其对登陆台风"桑美"的影响。高时空分辨率的雷达径向风资料在台风登陆前的3h同化窗内以每30min的频率同化进WRF模式(Weather Research and Forecasting)。研究结果表明:En3DVAR试验在3h同化窗内的均方根误差相比3DVAR试验改进显著,这可能得益于混合同化系统中提供的"流依赖"的集合协方差信息。系统性的诊断分析表明En3DVAR试验在台风内核区产生了较为明显正温度增量,对台风内核区的热力和动力结构均有较好调整,而3DVAR则在台风内核区产生了负温度增量;相比3DAVR试验,En3DVAR在采用了"流依赖"的集合协方差信息后还可以对背景场上的台风的位置进行系统性的偏差订正。总体而言,En3DVAR试验预报的台风路径和强度相比3DVAR改进显著,其正效果主要来源于混合背景误差协方差中的"流依赖"集合协方差信息。
文摘Co(En)\-3MoO\-4 was synthesized by using the method of hydrothermal synthesis and characterized by elemental analysis, IR, ESR and single\|crystal X\|ray methods. It crystallizes in hexagonal space group \%P3C1\% with \{\%a\%=1\^596 4(2) nm\}, \{\%b\%=1\^596 4(2) nm\}, \%c\%=\{0\^993 5(2)\} nm, \%α=β\%=90°, \%γ\%=120°, \%M\%\-c=399\^18, \%V\%=2\^192 6(6) nm\+3, \%D\%\-c=1\^814 g/nm\+3, \%Z\%=6, \%F\%(000)=1 218, \%R\%\-1=0\^070 3, \%R\%\-w=0\^220 7. According to separation of anion which acted on electrostatic potential, the anion and cation ions formed a type of organic and inorganic material.
基金supported by the National Natural Science Foundation of China (Grant No. 40705035)the National High Technology Research and Development Program of China (863 Program) (Grant Nos. 2009AA12Z129 and 2007AA12Z144)
文摘Land surface models are often highly nonlinear with model physics that contain parameterized discontinuities. These model attributes severely limit the application of advanced variational data assimilation methods into land data assimilation. The ensemble Kalman filter (EnKF) has been widely employed for land data assimilation because of its simple conceptual formulation and relative ease of implementation. An updated ensemble-based three-dimensional variational assimilation (En3-DVar) method is proposed for land data assimilation.This new method incorporates Monte Carlo sampling strategies into the 3-D variational data assimilation framework. The proper orthogonal decomposition (POD) technique is used to efficiently approximate a forecast ensemble produced by the Monte Carlo method in a 3-D space that uses a set of base vectors that span the ensemble. The data assimilation process is thus significantly simplified. Our assimilation experiments indicate that this new En3-DVar method considerably outperforms the EnKF method by increasing assimilation precision. Furthermore, computational costs for the new En3-DVar method are much lower than for the EnKF method.
文摘A new compound, \[Ni(en)\-3\]\-2\[Ni(en)\-2(H\-2O)\-2\]\[As\-6V\-\{15\}O\-\{42\}\]·4H\-2O, was first prepared by hydrothermal synthesis and characterized by elemental analysis, IR, TGA\|DSC, ESR and single crystal X\|ray diffraction. Crystal data: monoclinic, space group \%C\-c, a\%=1\^523 6(3) nm, \%b\%=2\^051 8(4) nm, \%c\%=2\^395 9(5) nm, \%β=97\^41(3)°, V\%=7\^427(3) nm\+3, \%Z=4, R=0\^057 0, wR\-2=0\^135 7\%. The polyanion consists of six AsO\-3 pyramids and fifteen VO\-5 pyramids. Counterions are complex ions with octahedral structure, which consist of NH\-2CH\-2CH\-2NH\-2 and Ni\+\{2+\}.
文摘Co(en) 3V 3O 6·H 2O has been synthesized by using hydrothermal method and characterized by IR, ICP, XPS and X ray diffraction analysis. The results of the X ray diffraction analysis show that structure of Co(en) 3(VO 3) 3·H 2O is orthorhombic with P2(1)2(1)2(1) , and the crystal data are a =0 819 2(7) nm, b =1.263 9(1) nm, c =1.804 8(2) nm, V =1.868 8(3) nm 3, Z=4, D c=1.973 g/cm 3, F (000)=1 124, R 1=0.040 7, wR 2=0.094 9, ( Δ/ρ ) max =706 e/nm 3 and ( Δ/ρ ) min =-452 e/nm 3. The results of XPS show that the Co 2+ was oxidized to Co 3+ (en) 3 at about pH=7.0 in the aqueous solution.
基金The Key Project of Chinese Natural Science Foundation under contract No.41330960the Chinese Polar Environment Comprehensive Investigation and Assessment Programs under contract No.CHINARE2014-04-03-01
文摘In this study the steric height anomaly which is calculated from the hydrological data （EN3） is compared with the sea level anomaly derived from satellite altimetry in the Nordic Seas. The overall pattern of steric height is that it is higher in the margin area and lower in the middle area. The extreme values of steric height linear change from 1993 to 2010 occur in the Lofoten Basin and off the Norwegian coast, respectively. Such a distribution may be partly attributed to the freshening trend of the Nordic Seas. The correlation between SLA （sea level anomaly） and SHA （steric height anomaly） is not uniform over the Nordic Seas. The time series of SLA and SHA agree well in the Lofoten Basin and northern Norwegian Basin, and worse in the northern Norwegian Sea, implying that the baroclinic effect plays a dominant role in most areas in the Norwegian Sea and the barotropic effect plays a dominant role in the northern Norwegian Sea. The weaker correlations between SLA and SHA in the Greenland and Iceland Seas lead a conclusion that the barotropic contribution is significant in these areas. The area-mean SHA over the entire Nordic Seas has similar amplitudes compared with the SLA during 1996-2002, but SHA has become lower than SLA, being less than half of SLA since 2006.
基金supported by the National Basic Research Program of China(Grant Nos.2012CB955202and2012CB41740)the National Natural Science Foundation of China(Grant Nos.41075064,41176014,and41006016)
文摘El Nio events in the central equatorial Pacific (CP) are gaining increased attention,due to their increasing intensity within the global warming context.Various physical processes have been identified in the climate system that can be responsible for the modulation of El Nio,especially the effects of interannual salinity variability.In this work,a comprehensive data analysis is performed to illustrate the effects of interannual salinity variability using surface and subsurface salinity fields from the Met Office ENSEMBLES (EN3) quality controlled ocean dataset.It is demonstrated that during the developing phase of an El Nio event,a negative sea surface salinity (SSS) anomaly in the western-central basin acts to freshen the mixed layer (ML),decrease oceanic density in the upper ocean,and stabilize the upper layers.These related oceanic processes tend to reduce the vertical mixing and entrainment of subsurface water at the base of the ML,which further enhances the warm sea surface temperature (SST) anomalies associated with the El Nio event.However,the effects of interannually variable salinity are much more significant during the CP-El Nio than during the eastern Pacific (EP) El Nio,indicating that the salinity effect might be an important contributor to the development of CP-El Nio events.
