This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studi...This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored.展开更多
In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size...In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size).The data from measurements show that in the upper atmosphere the existence of an upper jet is important to the transition cyclone.When Mindulle moved to the area of the upper jet entrance,where high-altitude divergence existed, the pumping of the high-altitude divergence would enhance the vertical motion and low-level cyclone convergence. The enhanced vertical motion was confirmed by the simulation results and indicated that the existence of upper divergence enhanced the vertical motion which was favorable for the maintenance of Typhoon Mindulle.The process of extratropical transition (ET) and re-intensification always accompanies the process of cold air invasion. This process enhances the baroclinicity of the atmosphere and the formation of front at high altitudes, which converts baroclinic potential energy into kinetic energy and strengthens the cyclone vortex.The distributions of equivalent potential temperature (θe) and temperature anomalies show that the warm-core of the typhoon at the tropopause aids the re-intensification of the system. As the typhoon reenters the ocean, latent heat flux (LHF) increases in the north and west and the strong reflectivity and vertical motion occur in the east and southeast,and the west.With the re-intensification of the typhoon the wind field evolves from an oval to a circle at the lower atmosphere, the area coverage by high winds increases, and the distribution of the tangential wind shows an asymmetric pattern.展开更多
Petrological,chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants(>3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the...Petrological,chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants(>3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the Rangrim Massif.In the massif,the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga,its important growing period was 2.8-2.5 Ga.The subsequent expansion period of the Rangrim Massif was 2.4-2.2 Ga.The division events occurred in 1.85 Ga and in the Late Paleoproterozoic--Early Mesopro-terozoic,respectively.Since then the massif was relatively stable.However,the last division of the Rangrim Massif occurred at 793 Ma.展开更多
Copper complexing ligands concentration (C C) and conditional stability constant of the sea surface microlayer (SML) and subsurface layer (SSL) samples, collected from Daya Bay of Guangdong Province and Jiaozhou Bay o...Copper complexing ligands concentration (C C) and conditional stability constant of the sea surface microlayer (SML) and subsurface layer (SSL) samples, collected from Daya Bay of Guangdong Province and Jiaozhou Bay of Shandong Province, were determined by anodic stripping voltammetry (ASV) technique. C C of Daya Bay in the SML ranged from 6.19×10-7 to 3.52×10-7 mol/L. C C of Jiaozhou Bay in the SML ranged from 5.30×10-7 to 3.03×10-7 mol/L in August 1998 and from 3.46×10-7 to 1.36×10-7 mol/L in May 2000. The C C concentrations were higher in all surface microlayer samples, compared with corresponding subsurface samples. The average enrichment factors of copper complexation in the SML observed above were 1.58, 1.41 and 1.56, respectively. The enrichment of C C concentration in the microlayer demonstrated that organic ligands had certain buffer action on the toxicity of the enriched trace metals in the same layer. Conditional stability constants of the SML in Jiaozhou Bay were lower than those of the SSL; however, it showed just opposite for Daya Bay. BOD (biological oxygen demand) and COD (chemical oxygen demand) indicated the organic matter content, also showed enriched in the SML. C C had an obvious relationship with BOD or COD.展开更多
This paper tests the impacts of cloud-induced mass forcing on the moist potential vorticity (MPV) anomaly associated with torrential rains caused by Typhoon No.9914 (Dan) by using fine model simulation data output...This paper tests the impacts of cloud-induced mass forcing on the moist potential vorticity (MPV) anomaly associated with torrential rains caused by Typhoon No.9914 (Dan) by using fine model simulation data outputted by the Fifth-Generation NCAR / Penn State Mesoscale Model (MMS). The diagnostic results show that the positive MPV anomaly region, which is obtained by integrating the MPV from 600 hPa to 300 hPa in the vertical, roughly coincides with the precipitation at their synchronous stages either in position or in the distribution pattem, and the maximum positive MPV area of Dan is located mainly between 600 hPa and 300 hPa, which is much higher than torrential rain cases. Further analyses also showed that the value of positive MPV anomaly increased or decreased with the development of Dan, and the positive MPV anomaly may also be served as a tracer to indicate the evolution of tropical cyclone intensity.展开更多
In utility power system, electricity demand is being covered largely by fossil fueled power generation, which contributes high level of GHG (greenhouse gas) emission and causes global warming worldwide. In order to ...In utility power system, electricity demand is being covered largely by fossil fueled power generation, which contributes high level of GHG (greenhouse gas) emission and causes global warming worldwide. In order to reduce GHG emission level, most of the countries in the world targeting towards green energy that is power generation from RE (renewable energy) sources. In this paper, it is considered to study prospects of RE sources in particular, solar and wind in Victoria State which are abundant as compared to other sources of renewable. The wind and solar energy feasibility study and sensitivity analysis has been done for Victoria with the aid of HOMER (hybrid optimization model of electric renewable) simulation software. From the study, it has clearly evicted that wind energy combinational HPS (hybrid power system) has more contribution, and high potential than solar PV (photovoltaic) systems for a particular location. This study also investigates the influences of energy storage in the proposed HPS.展开更多
I am an Australian living in Quanzhou, Fujian Province. I am employed as an English conversation teacher in a local middle school. I enjoy reading China Today and would be interested in writing an article on my impres...I am an Australian living in Quanzhou, Fujian Province. I am employed as an English conversation teacher in a local middle school. I enjoy reading China Today and would be interested in writing an article on my impression of Quanzhou, or my experiences as a teacher in middle school or other topics that may be of interest to your readers.展开更多
Obesity is known to be a major risk factor of type 2 diabetes (T2D) and responsible for most lipid abnormalities associated with the disease but limited data on such association are available for diabetic patients o...Obesity is known to be a major risk factor of type 2 diabetes (T2D) and responsible for most lipid abnormalities associated with the disease but limited data on such association are available for diabetic patients of Igbo ethnicity in the South East region of Nigeria. A case-control study involving 72 T2D patients and 75 non-diabetic (ND) patients (control) ofIgbo ethnicity was conducted. Demographic and anthropometric data were obtained followed by blood collection for the determination of fasting blood sugar (FBS), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL). Obesity based on waist circumference (WC) was significantly higher (p 〈 0.001) in T2D patients compared to their non-diabetic counterparts. Similarly, TC, TG and LDL levels were significantly (p 〈 0.001) higher in T2D patients while HDL was significantly lower (p 〈 0.001) in T2D patients compared to the control. The proportion of dyslipidaemia characterized by high TC, high TG, high LDL and low HDL was significantly higher (p 〈 0.001) in T2D patients. BMI correlated positively (p 〈 0.05) with WC, TC, and LDL while FBS correlated positively (p 〈 0.05) with TG but negatively with HDL. In conclusion, dyslipidaemia characterised by hypercholesterolaemia, hypertriglyceridaemia, elevated LDL and reduced HDL, as well as obesity were associated with T2D and correlated with FBS in this population.展开更多
Based on the conduction and transformation of the thermal infrared radiative transfer equation of water target,a twinchannel difference model(DM) was proposed to improve the calibration precision by conquering the lim...Based on the conduction and transformation of the thermal infrared radiative transfer equation of water target,a twinchannel difference model(DM) was proposed to improve the calibration precision by conquering the limitation that the atmospheric condition when image is acquiring cannot be truly obtained in the traditional radiometric simulation calibration method.The analysis of surface,atmosphere and top-of-atmosphere(TOA) radiative energy decomposition demonstrated that the apparent TOA radiance of the uncalibrated channel is the differential combination of two reference channels.The DM avoids impacts from atmospheric temperature and density.The only impact is from water vapor(WV) content.Based on the fitting error analysis of 742 mid-latitude atmospheric profiles(column WV content:0-5×10 3 atm cm) selected from TIGR database,the DM is insensitive to WV content.The maximum error is less than 0.2 K when the view zenith angels(VZAs) of reference channels and uncalibrated channel are less than 30.The error becomes 0.3 K when VZAs range from 30 to 40 and 0.6 K when VZAs are in 40-50.Because the uncertainty increases when VZAs are larger than 50,the best range of VZAs is 30-50.The vicarious calibration results at Lake Qinghai field indicated that the calibration precision of the DM cross-calibration by using MODIS bands 31 and 32 as reference channels to calibrate IRS band 08 is similar to that of vicarious calibration.Therefore,the DM is a reliable alternative tool for sensor on-orbit calibration and validation with high precision and frequency.展开更多
基金Under the jointly auspices of the Special Public Research for Meteorological Industry (No. GYHY200806009)Wind Energy Resources Detailed Survey and Assessment WorkEU-China Energy and Environment Program (No. Europe Aid/ 123310/D/Ser/CN)
文摘This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored.
基金supported by the National Natural Science Foundation of China(Nos.40876004,40890155 and 40675060)National 973 Project(Nos.2009CB-421500 and 2007CB411801)
文摘In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size).The data from measurements show that in the upper atmosphere the existence of an upper jet is important to the transition cyclone.When Mindulle moved to the area of the upper jet entrance,where high-altitude divergence existed, the pumping of the high-altitude divergence would enhance the vertical motion and low-level cyclone convergence. The enhanced vertical motion was confirmed by the simulation results and indicated that the existence of upper divergence enhanced the vertical motion which was favorable for the maintenance of Typhoon Mindulle.The process of extratropical transition (ET) and re-intensification always accompanies the process of cold air invasion. This process enhances the baroclinicity of the atmosphere and the formation of front at high altitudes, which converts baroclinic potential energy into kinetic energy and strengthens the cyclone vortex.The distributions of equivalent potential temperature (θe) and temperature anomalies show that the warm-core of the typhoon at the tropopause aids the re-intensification of the system. As the typhoon reenters the ocean, latent heat flux (LHF) increases in the north and west and the strong reflectivity and vertical motion occur in the east and southeast,and the west.With the re-intensification of the typhoon the wind field evolves from an oval to a circle at the lower atmosphere, the area coverage by high winds increases, and the distribution of the tangential wind shows an asymmetric pattern.
文摘Petrological,chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants(>3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the Rangrim Massif.In the massif,the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga,its important growing period was 2.8-2.5 Ga.The subsequent expansion period of the Rangrim Massif was 2.4-2.2 Ga.The division events occurred in 1.85 Ga and in the Late Paleoproterozoic--Early Mesopro-terozoic,respectively.Since then the massif was relatively stable.However,the last division of the Rangrim Massif occurred at 793 Ma.
基金Supported by subproject of the China’s "Ninth Five Year Plan" Scientific Research Project No. 97-926-04-03 the Natural Science Foundation of China (No. 40076020, 40376022) the Doctoral Research Program of Higher Education (No. 98042304) and KZ95T-04-04-04 Fund.
文摘Copper complexing ligands concentration (C C) and conditional stability constant of the sea surface microlayer (SML) and subsurface layer (SSL) samples, collected from Daya Bay of Guangdong Province and Jiaozhou Bay of Shandong Province, were determined by anodic stripping voltammetry (ASV) technique. C C of Daya Bay in the SML ranged from 6.19×10-7 to 3.52×10-7 mol/L. C C of Jiaozhou Bay in the SML ranged from 5.30×10-7 to 3.03×10-7 mol/L in August 1998 and from 3.46×10-7 to 1.36×10-7 mol/L in May 2000. The C C concentrations were higher in all surface microlayer samples, compared with corresponding subsurface samples. The average enrichment factors of copper complexation in the SML observed above were 1.58, 1.41 and 1.56, respectively. The enrichment of C C concentration in the microlayer demonstrated that organic ligands had certain buffer action on the toxicity of the enriched trace metals in the same layer. Conditional stability constants of the SML in Jiaozhou Bay were lower than those of the SSL; however, it showed just opposite for Daya Bay. BOD (biological oxygen demand) and COD (chemical oxygen demand) indicated the organic matter content, also showed enriched in the SML. C C had an obvious relationship with BOD or COD.
基金State Key Development Program for Basic Research of China (2009CB421505)National Natural Science Foundation of China (40505009)+1 种基金NMC-TIGGE Program (GYHY200706001)Project of State Key Laboratory of Severe Weather (2008LASW-A01)
文摘This paper tests the impacts of cloud-induced mass forcing on the moist potential vorticity (MPV) anomaly associated with torrential rains caused by Typhoon No.9914 (Dan) by using fine model simulation data outputted by the Fifth-Generation NCAR / Penn State Mesoscale Model (MMS). The diagnostic results show that the positive MPV anomaly region, which is obtained by integrating the MPV from 600 hPa to 300 hPa in the vertical, roughly coincides with the precipitation at their synchronous stages either in position or in the distribution pattem, and the maximum positive MPV area of Dan is located mainly between 600 hPa and 300 hPa, which is much higher than torrential rain cases. Further analyses also showed that the value of positive MPV anomaly increased or decreased with the development of Dan, and the positive MPV anomaly may also be served as a tracer to indicate the evolution of tropical cyclone intensity.
文摘In utility power system, electricity demand is being covered largely by fossil fueled power generation, which contributes high level of GHG (greenhouse gas) emission and causes global warming worldwide. In order to reduce GHG emission level, most of the countries in the world targeting towards green energy that is power generation from RE (renewable energy) sources. In this paper, it is considered to study prospects of RE sources in particular, solar and wind in Victoria State which are abundant as compared to other sources of renewable. The wind and solar energy feasibility study and sensitivity analysis has been done for Victoria with the aid of HOMER (hybrid optimization model of electric renewable) simulation software. From the study, it has clearly evicted that wind energy combinational HPS (hybrid power system) has more contribution, and high potential than solar PV (photovoltaic) systems for a particular location. This study also investigates the influences of energy storage in the proposed HPS.
文摘I am an Australian living in Quanzhou, Fujian Province. I am employed as an English conversation teacher in a local middle school. I enjoy reading China Today and would be interested in writing an article on my impression of Quanzhou, or my experiences as a teacher in middle school or other topics that may be of interest to your readers.
文摘Obesity is known to be a major risk factor of type 2 diabetes (T2D) and responsible for most lipid abnormalities associated with the disease but limited data on such association are available for diabetic patients of Igbo ethnicity in the South East region of Nigeria. A case-control study involving 72 T2D patients and 75 non-diabetic (ND) patients (control) ofIgbo ethnicity was conducted. Demographic and anthropometric data were obtained followed by blood collection for the determination of fasting blood sugar (FBS), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL). Obesity based on waist circumference (WC) was significantly higher (p 〈 0.001) in T2D patients compared to their non-diabetic counterparts. Similarly, TC, TG and LDL levels were significantly (p 〈 0.001) higher in T2D patients while HDL was significantly lower (p 〈 0.001) in T2D patients compared to the control. The proportion of dyslipidaemia characterized by high TC, high TG, high LDL and low HDL was significantly higher (p 〈 0.001) in T2D patients. BMI correlated positively (p 〈 0.05) with WC, TC, and LDL while FBS correlated positively (p 〈 0.05) with TG but negatively with HDL. In conclusion, dyslipidaemia characterised by hypercholesterolaemia, hypertriglyceridaemia, elevated LDL and reduced HDL, as well as obesity were associated with T2D and correlated with FBS in this population.
基金supported by the National Natural Science Foundation of China (Grant No. 40971227)the International Corporation Program of Science and Technology Ministry of China (Grant No. 2010DFA21880)
文摘Based on the conduction and transformation of the thermal infrared radiative transfer equation of water target,a twinchannel difference model(DM) was proposed to improve the calibration precision by conquering the limitation that the atmospheric condition when image is acquiring cannot be truly obtained in the traditional radiometric simulation calibration method.The analysis of surface,atmosphere and top-of-atmosphere(TOA) radiative energy decomposition demonstrated that the apparent TOA radiance of the uncalibrated channel is the differential combination of two reference channels.The DM avoids impacts from atmospheric temperature and density.The only impact is from water vapor(WV) content.Based on the fitting error analysis of 742 mid-latitude atmospheric profiles(column WV content:0-5×10 3 atm cm) selected from TIGR database,the DM is insensitive to WV content.The maximum error is less than 0.2 K when the view zenith angels(VZAs) of reference channels and uncalibrated channel are less than 30.The error becomes 0.3 K when VZAs range from 30 to 40 and 0.6 K when VZAs are in 40-50.Because the uncertainty increases when VZAs are larger than 50,the best range of VZAs is 30-50.The vicarious calibration results at Lake Qinghai field indicated that the calibration precision of the DM cross-calibration by using MODIS bands 31 and 32 as reference channels to calibrate IRS band 08 is similar to that of vicarious calibration.Therefore,the DM is a reliable alternative tool for sensor on-orbit calibration and validation with high precision and frequency.