We attempt to compute the Surface Average Heat Flow (SAHF) from long-term temperature observations of one hundred seventy-seven observational points at the depths of 0.8, 1.6, and 3.2 m, which were relatively evenly...We attempt to compute the Surface Average Heat Flow (SAHF) from long-term temperature observations of one hundred seventy-seven observational points at the depths of 0.8, 1.6, and 3.2 m, which were relatively evenly distributed in China's Mainland. We first employ Fourier transformation to remove the influence of atmospheric temperature variations from the observation series, which are classified into the type of the steady-state temperature monotonously increasing with depth (type I) and other three types. Then we compare our results obtained from the data of type I, of which the values are thought to equal to those of the mean borehole heat flow, with those obtained from traditional heat flow observations mainly distributed in North China Craton. In computations of the SAHF at the observation stations, we deduce the thermal diffusivity and volumetric specific heat of the soil by employing harmonic solutions of the heat conduction equation for the same moisture group as the first step, and then we determine the SAHF using Fourier's law. Our results indicate that the SAHF derived from shallow earth geothermal data can reflect the heat flow field to a large extent.展开更多
Micromorphology of solonetz species with special attention to natric horizon was studied in microcatenas at the Dzhanybek Research Station (northwestern Caspian Lowland). The solonetzic (natric) horizon is easily iden...Micromorphology of solonetz species with special attention to natric horizon was studied in microcatenas at the Dzhanybek Research Station (northwestern Caspian Lowland). The solonetzic (natric) horizon is easily identified, and it occurs at varying depths, which are the criteria for subdividing solonetzes into 4 species, namely, crusty, shallow, medium and deep. In this sequence, the depth of humus-accumulative horizons increases, and the upper boundary of salinity manifestations goes down. The following micromorphological features are assumed as typical for natric horizons: angular blocky microstructures with partially accommodated aggregates having sharp boundaries and narrow plane-like packing voids; b-fabric speckled in the aggregates' centers and monostriated at their peripheries merging into stress coatings; very few interpedal voids; organo-clay coatings; humusenriched infillings; no calcite and gypsum pedofeatures. A complete set of "natric" features was found only in the crusty solonetz; the shallow solonetz lacks only illuviation coatings, while the medium and deep species have several modifications of fabric elements: blocky aggregates have a rounded shape and are penetrated by biogenic channels favoring their further biogenic reworking; plant residues became more abundant and diverse, and blackened tissues occur; illuviation clay coatings evolved into papules; stress coatings gave birth to striated b- fabrics, thus maintaining a high plasma orientation. The thin sections of natric horizons made 50 and 20 years ago were examined to study the influence of environmental changes (increase in precipitation and rise of ground water table) on micropedofeatures. The following processes took place: (i) in the topsoil: humus accumulation and biogenic structurization; (ii) in the natric horizon-re-arrangement of clay coatings into micromass b-fabrics; and (iii) in the lower part of the natric horizon-development of pseudosand fabric, calcite and gypsum formation. The trends revealed are in good agreement with the environmental events.展开更多
Regional Integrated Environment Modeling System Version 2.0 (RIEMS2.0) is now being developed by the Key Laboratory of Regional Climate-Environment for Temperate East Asia, Chinese Academy of Sciences. In order to tes...Regional Integrated Environment Modeling System Version 2.0 (RIEMS2.0) is now being developed by the Key Laboratory of Regional Climate-Environment for Temperate East Asia, Chinese Academy of Sciences. In order to test the sensitivity of the RIEMS2.0 model domain to simulate long-term climate and its change, and provide a basis for the further development and application of the model, the authors compared results between simulated and observed precipitation and surface-airtemperature using two model domains under different cumulus parameterization schemes. The model was driven by NCEP/NCAR re-analysis data with a simulation duration ranging from 1 January 1979 to 31 December 2007. There were no significant differences found in the spatial distributions of the simulated precipitation and surface-air-temperature, or interannual variations between the two model domains. There were, however, differences observed between the two model domain simulations of local sub-regions. The smaller model domain more accurately simulated precipitation, especially in summer (June, July, and August), and decreased the bias of surface-airtemperature, especially in winter (December, January, and February). The weak summer and winter monsoons simulated by the smaller model domain was a result of boundary forcings and may partially account for the improvements of this model.展开更多
The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU...The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan.The automatic groundwater sensors were installed for the corporation project between China and Japan.Combined with the monitoring results from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten.According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including discharge pattern in the piedmont plain, lateral recharge-runoff-discharge pattern in the piedmont plain, recharge-discharge pattern in the central channel zone, precipitation infiltration-evaporation pattern in the shallow groundwater region of the central plain, lateral recharge-evaporation pattern in the recharge-affected area along the Yellow River and infiltration-discharge-evaporation pattern in the littoral plain.Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted and the influencing factors of different dynamic patterns were compared.展开更多
This paper presents the contemporary motion and active deformation of South America plate and relative motion of Nazca-South America plate using space geodetic data. The South America plate is moving at average 14.5 m...This paper presents the contemporary motion and active deformation of South America plate and relative motion of Nazca-South America plate using space geodetic data. The South America plate is moving at average 14.5 mm/a with an azimuth of 15.2° and shrinking in the west-east at 10.9 mm/a. The geodetic deformations of sites with respect to the South America plate are in quite good agreement with the estimated deformations from NNR-NUVEL1A, but the deformation of the western South America regions is very large.展开更多
The hermeneutic concept of horizon contributes to the philosophical understanding of scientific cognition. In the context of scientific cognitive practices, the concept of horizon provides a way of understanding the d...The hermeneutic concept of horizon contributes to the philosophical understanding of scientific cognition. In the context of scientific cognitive practices, the concept of horizon provides a way of understanding the distinctive characteristics of scientific observation and knowing. Horizon is a key factor that facilitates the cognitive subject to select objects and their backgrounds. In order to make new accomplishment in scientific discoveries, it is essential to broaden the horizon and intzoduce new cognitive instrumentalities and methods. This requires people to be adept at finding out the limitations of their thinking and overcome them consciously. Conscious horizon expansion is essential to the integration of intuition and logical thinking process in scientific cognitive activities, as well as to the establishment of the essential connection/relation between different disciplines and research fields, prompting inter-disciplinary communication and producing methods of thinking. This article is an attempt to explore the significance of horizon for scientific cognition. As we will show, by integrating intuitive thinking and logical thinking through the expansion of horizon, a new cognitive model will be provided.展开更多
By using in situ daily observations in East China during 1961-2007 and NCEP reanalysis data, the methods of statistical analyses, urban minus rural and observation minus reanalysis, it is revealed that the observed cl...By using in situ daily observations in East China during 1961-2007 and NCEP reanalysis data, the methods of statistical analyses, urban minus rural and observation minus reanalysis, it is revealed that the observed climate change and surface warming in East China were mainly induced by urbanization. The results show that East China has experienced two warmer periods of 1930s and 1980s in the past century; from 1951 to 2007, the regional mean temperature increased at a rate of 0.14℃ per decade; heat waves happened in urban center more frequently, and local climate showed a warming and dry trend; there was no significant linear trend in regional mean precipitation in the past 50 years. Urbanization was a crucial element for the regional warming; about 44% of the warming was due to heat island effect in the mega city.展开更多
We have collected GPS data in the period of 1999-2007 from the Crustal Motion Observation Network of China along the Zhangjiakou-Bohai fault and its adjacent regions to study the characteristics of present-day crustal...We have collected GPS data in the period of 1999-2007 from the Crustal Motion Observation Network of China along the Zhangjiakou-Bohai fault and its adjacent regions to study the characteristics of present-day crustal horizontal motion velocities in the research zone.Strain rate components are computed in the spheric coordinate system by the least square collocation method.According to the spatial distribution of the principal strain rate,dilation rate and maximum shear strain rate derived from GPS measurements,this paper analyses the deformation of the subordinary faults of the Zhangjiakou-Bohai fault.The principal compression strain rates are apparently greater than the principal extension strain rates.The larger shear strain rate is mainly in and around the Xianghe,Wenan and Tangshan areas in Hebei Province.According to the profiles across different segments of the Zhangjiakou-Bohai fault,the three segments glong the Zhangjiakou-Bohai fault show an obviously left-lateal strike-slip and compression characteristics.By analysis of the motion characteristics of the blocks,e.g.the Yanshan block,North China Plain block,Ordos block,and Ludong-Huanghai block in and around the North China region,this paper speculates that the dynamics of the motion styles of Zhangjiakou-Bohai fault may directly come from the relative movement between the Yanshan block and the North China plain block,and the ultimate dynamics may be the results of the collison between Indian plate and Eurasian plate,and the persistent northeastward extrusion of the Indian plate.展开更多
The 1-year(2009-2010) measurements are analyzed of the urban surface energy balance(SEB) obtained from the sensors located at three vertical layers of a 325-m tower in downtown Beijing.Results show that:(1) The...The 1-year(2009-2010) measurements are analyzed of the urban surface energy balance(SEB) obtained from the sensors located at three vertical layers of a 325-m tower in downtown Beijing.Results show that:(1) The measurements from the 325-m tower represent the SEB characteristics of the cities located in semi-humid warm-temperate continental monsoon climate zone.In a typical hot and rainy summer,cold and dry winter,the measured Bowen ratio is minimum in summer and maximum in winter.The Bowen ratio measured at 140 m for spring,summer,autumn,and winter are 2.86,0.82,1.17,and 4.16 respectively.(2) At the height of 140-m(in the constant flux layer),the noontime albedo is ~0.10 for summer,~0.12 for spring and autumn,and ~0.14 for winter.The ratios of daytime sensible heat flux,latent heat flux,and storage heat flux to net radiation are 0.25,0.16,and 0.59 for clear-sky days,and 0.33,0.19,and 0.48 for cloudy days respectively.(3) Under clear-sky days,the nighttime sensible heat flux is almost zero,but the latent heat flux is greater than zero.For cloudy days,the nighttime sensible heat flux is slightly greater than the latent heat flux in winter.The nighttime upward heat flux is presumably due to the anthropogenic release(mainly latent heat for summer,while latent and sensible heat for winter).展开更多
基金supported by the National Natural Science Foundation of China(Grant No.4087404741174084)
文摘We attempt to compute the Surface Average Heat Flow (SAHF) from long-term temperature observations of one hundred seventy-seven observational points at the depths of 0.8, 1.6, and 3.2 m, which were relatively evenly distributed in China's Mainland. We first employ Fourier transformation to remove the influence of atmospheric temperature variations from the observation series, which are classified into the type of the steady-state temperature monotonously increasing with depth (type I) and other three types. Then we compare our results obtained from the data of type I, of which the values are thought to equal to those of the mean borehole heat flow, with those obtained from traditional heat flow observations mainly distributed in North China Craton. In computations of the SAHF at the observation stations, we deduce the thermal diffusivity and volumetric specific heat of the soil by employing harmonic solutions of the heat conduction equation for the same moisture group as the first step, and then we determine the SAHF using Fourier's law. Our results indicate that the SAHF derived from shallow earth geothermal data can reflect the heat flow field to a large extent.
基金supported by the Russian Foundation for Basic Studies (project 08-04-01333)
文摘Micromorphology of solonetz species with special attention to natric horizon was studied in microcatenas at the Dzhanybek Research Station (northwestern Caspian Lowland). The solonetzic (natric) horizon is easily identified, and it occurs at varying depths, which are the criteria for subdividing solonetzes into 4 species, namely, crusty, shallow, medium and deep. In this sequence, the depth of humus-accumulative horizons increases, and the upper boundary of salinity manifestations goes down. The following micromorphological features are assumed as typical for natric horizons: angular blocky microstructures with partially accommodated aggregates having sharp boundaries and narrow plane-like packing voids; b-fabric speckled in the aggregates' centers and monostriated at their peripheries merging into stress coatings; very few interpedal voids; organo-clay coatings; humusenriched infillings; no calcite and gypsum pedofeatures. A complete set of "natric" features was found only in the crusty solonetz; the shallow solonetz lacks only illuviation coatings, while the medium and deep species have several modifications of fabric elements: blocky aggregates have a rounded shape and are penetrated by biogenic channels favoring their further biogenic reworking; plant residues became more abundant and diverse, and blackened tissues occur; illuviation clay coatings evolved into papules; stress coatings gave birth to striated b- fabrics, thus maintaining a high plasma orientation. The thin sections of natric horizons made 50 and 20 years ago were examined to study the influence of environmental changes (increase in precipitation and rise of ground water table) on micropedofeatures. The following processes took place: (i) in the topsoil: humus accumulation and biogenic structurization; (ii) in the natric horizon-re-arrangement of clay coatings into micromass b-fabrics; and (iii) in the lower part of the natric horizon-development of pseudosand fabric, calcite and gypsum formation. The trends revealed are in good agreement with the environmental events.
基金supported by the National Natural Science Foundation of China (Grant No. 40975053)the National Basic Research Program of China (Grant No. 2006CB400500)
文摘Regional Integrated Environment Modeling System Version 2.0 (RIEMS2.0) is now being developed by the Key Laboratory of Regional Climate-Environment for Temperate East Asia, Chinese Academy of Sciences. In order to test the sensitivity of the RIEMS2.0 model domain to simulate long-term climate and its change, and provide a basis for the further development and application of the model, the authors compared results between simulated and observed precipitation and surface-airtemperature using two model domains under different cumulus parameterization schemes. The model was driven by NCEP/NCAR re-analysis data with a simulation duration ranging from 1 January 1979 to 31 December 2007. There were no significant differences found in the spatial distributions of the simulated precipitation and surface-air-temperature, or interannual variations between the two model domains. There were, however, differences observed between the two model domain simulations of local sub-regions. The smaller model domain more accurately simulated precipitation, especially in summer (June, July, and August), and decreased the bias of surface-airtemperature, especially in winter (December, January, and February). The weak summer and winter monsoons simulated by the smaller model domain was a result of boundary forcings and may partially account for the improvements of this model.
基金National Natural Sciences Foundation of China,No.40671034 No.40830636
文摘The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan.The automatic groundwater sensors were installed for the corporation project between China and Japan.Combined with the monitoring results from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten.According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including discharge pattern in the piedmont plain, lateral recharge-runoff-discharge pattern in the piedmont plain, recharge-discharge pattern in the central channel zone, precipitation infiltration-evaporation pattern in the shallow groundwater region of the central plain, lateral recharge-evaporation pattern in the recharge-affected area along the Yellow River and infiltration-discharge-evaporation pattern in the littoral plain.Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted and the influencing factors of different dynamic patterns were compared.
文摘This paper presents the contemporary motion and active deformation of South America plate and relative motion of Nazca-South America plate using space geodetic data. The South America plate is moving at average 14.5 mm/a with an azimuth of 15.2° and shrinking in the west-east at 10.9 mm/a. The geodetic deformations of sites with respect to the South America plate are in quite good agreement with the estimated deformations from NNR-NUVEL1A, but the deformation of the western South America regions is very large.
文摘The hermeneutic concept of horizon contributes to the philosophical understanding of scientific cognition. In the context of scientific cognitive practices, the concept of horizon provides a way of understanding the distinctive characteristics of scientific observation and knowing. Horizon is a key factor that facilitates the cognitive subject to select objects and their backgrounds. In order to make new accomplishment in scientific discoveries, it is essential to broaden the horizon and intzoduce new cognitive instrumentalities and methods. This requires people to be adept at finding out the limitations of their thinking and overcome them consciously. Conscious horizon expansion is essential to the integration of intuition and logical thinking process in scientific cognitive activities, as well as to the establishment of the essential connection/relation between different disciplines and research fields, prompting inter-disciplinary communication and producing methods of thinking. This article is an attempt to explore the significance of horizon for scientific cognition. As we will show, by integrating intuitive thinking and logical thinking through the expansion of horizon, a new cognitive model will be provided.
基金supported by the Climate Change Special Foundation of China Meteorological Administration(No.CCSF-09-10 and CCSF201202)National Natural Science Foundation of China (No.41001023)+1 种基金CAS Pilot Special Project (No.XDA05090204)Jiangsu Research and Innovation Program for Graduate Student (No.CXZZ12-0497)
文摘By using in situ daily observations in East China during 1961-2007 and NCEP reanalysis data, the methods of statistical analyses, urban minus rural and observation minus reanalysis, it is revealed that the observed climate change and surface warming in East China were mainly induced by urbanization. The results show that East China has experienced two warmer periods of 1930s and 1980s in the past century; from 1951 to 2007, the regional mean temperature increased at a rate of 0.14℃ per decade; heat waves happened in urban center more frequently, and local climate showed a warming and dry trend; there was no significant linear trend in regional mean precipitation in the past 50 years. Urbanization was a crucial element for the regional warming; about 44% of the warming was due to heat island effect in the mega city.
基金funded by the Technology and Innovation Foundation of the First Monitoring Center of China Earthquake Administration (FMC2014018)Science for Earthquake Resilience Project of China Earthquake Administration (XH15062)+1 种基金 National Natural Science Foundation Item of China (4137221541272233)
文摘We have collected GPS data in the period of 1999-2007 from the Crustal Motion Observation Network of China along the Zhangjiakou-Bohai fault and its adjacent regions to study the characteristics of present-day crustal horizontal motion velocities in the research zone.Strain rate components are computed in the spheric coordinate system by the least square collocation method.According to the spatial distribution of the principal strain rate,dilation rate and maximum shear strain rate derived from GPS measurements,this paper analyses the deformation of the subordinary faults of the Zhangjiakou-Bohai fault.The principal compression strain rates are apparently greater than the principal extension strain rates.The larger shear strain rate is mainly in and around the Xianghe,Wenan and Tangshan areas in Hebei Province.According to the profiles across different segments of the Zhangjiakou-Bohai fault,the three segments glong the Zhangjiakou-Bohai fault show an obviously left-lateal strike-slip and compression characteristics.By analysis of the motion characteristics of the blocks,e.g.the Yanshan block,North China Plain block,Ordos block,and Ludong-Huanghai block in and around the North China region,this paper speculates that the dynamics of the motion styles of Zhangjiakou-Bohai fault may directly come from the relative movement between the Yanshan block and the North China plain block,and the ultimate dynamics may be the results of the collison between Indian plate and Eurasian plate,and the persistent northeastward extrusion of the Indian plate.
基金supported by National Natural Science Foundation of China (Grant No. 41175015)the Ministry of Science and Technology of China (Grant Nos. GYHY200906026,GYHY201106050,2008BAC37B04,and 2006BAJ02A01)
文摘The 1-year(2009-2010) measurements are analyzed of the urban surface energy balance(SEB) obtained from the sensors located at three vertical layers of a 325-m tower in downtown Beijing.Results show that:(1) The measurements from the 325-m tower represent the SEB characteristics of the cities located in semi-humid warm-temperate continental monsoon climate zone.In a typical hot and rainy summer,cold and dry winter,the measured Bowen ratio is minimum in summer and maximum in winter.The Bowen ratio measured at 140 m for spring,summer,autumn,and winter are 2.86,0.82,1.17,and 4.16 respectively.(2) At the height of 140-m(in the constant flux layer),the noontime albedo is ~0.10 for summer,~0.12 for spring and autumn,and ~0.14 for winter.The ratios of daytime sensible heat flux,latent heat flux,and storage heat flux to net radiation are 0.25,0.16,and 0.59 for clear-sky days,and 0.33,0.19,and 0.48 for cloudy days respectively.(3) Under clear-sky days,the nighttime sensible heat flux is almost zero,but the latent heat flux is greater than zero.For cloudy days,the nighttime sensible heat flux is slightly greater than the latent heat flux in winter.The nighttime upward heat flux is presumably due to the anthropogenic release(mainly latent heat for summer,while latent and sensible heat for winter).