Due to the decrease in grid size associated with the convergence of meridians toward the poles inspherical coordinates, the time steps in many global climate models with finite-difference method are restrictedto be un...Due to the decrease in grid size associated with the convergence of meridians toward the poles inspherical coordinates, the time steps in many global climate models with finite-difference method are restrictedto be unpleasantly small. To overcome the problem, a reduced grid is introduced to LASG/IAP world oceangeneral circulation models. The reduced grid is implemented successfully in the coarser resolutions versionmodel L30T63 at first. Then, it is carried out in the improved version model LICOM with finer resolutions. Inthe experiment with model L30T63, under time step unchanged though, execution time per single model run isshortened significantly owing to the decrease of grid number and filtering execution in high latitudes. Resultsfrom additional experiments with L30T63 show that the time step of integration can be quadrupled at most inreduced grid with refinement ratio 3. In the experiment with model LICOM and with the model’s original timestep unchanged, the model covered area is extended to the whole globe from its original case with the grid pointof North Pole considered as an isolated island and the results of experiment are shown to be acceptable.展开更多
The interdecadal circumglobal teleconnection (ID-CGT) pattern is the dominant circulation mode over the NH during boreal summer on the interdecadal time scale. Its temporal evolution is synchronous with that of the ...The interdecadal circumglobal teleconnection (ID-CGT) pattern is the dominant circulation mode over the NH during boreal summer on the interdecadal time scale. Its temporal evolution is synchronous with that of the Atlantic Multidecadal Oscillation (AMO). In this study, through analyzing the results of sensitivity experiments using five AGCMs driven by specified AMO-related SST anomalies (SSTAs) in the North Atlantic, the authors investigate whether the ID-CGT is excited by the AMO. Two out of the five models simulate the barotropic stationary wave pattern located along the westerly jet, suggesting that the ID-CGT pattern should be excited, at least partially, by the AMO- related SSTAs. Model results suggest that the ID-CGT pattern plays a role in linking the AMO and NH summer land SAT perturbations on the interdecadal time scale.展开更多
Two numerical experiments were performed by using the Community Atmosphere Model version 3 (CAM3) with different sea ice datasets to assess the con- tribution of the decline of Arctic sea ice to warming in the North...Two numerical experiments were performed by using the Community Atmosphere Model version 3 (CAM3) with different sea ice datasets to assess the con- tribution of the decline of Arctic sea ice to warming in the Northern Hemisphere. One observed sea ice cover data; experiment was driven by for the other one, the authors used the sea ice data of the 4xCO2 scenario simulated by the fourth-generation European Centre Hamburg atmos- pheric general circulation Model of Istituto Nazionale di Geofisica e Vulcanologia, Italy (1NGV ECHAM4). The comparison of the two experiments indicates that the de- cline of the Arctic sea ice leads to a dramatic wanning over the high latitudes of the Northern Hemisphere, char- acterized by a maximum warming of more than 26~C over the Arctic region. The significant warming is closely re- lated to the enhanced atmospheric heat source. A 40-60 W m-2 increase in the apparent heat source was simulated in winter due to the decline of Arctic sea ice. In contrast, no significant change was found in the atmospheric ap- parent heat source in summer. As a result, the summer temperature change induced by the decline of Arctic sea ice appears to be weak. This study suggests that accurate sea ice cover data is crucial for future climate projection of air temperature in high latitudes.展开更多
AIM: To evaluate serum levels of N-terminal pro-brain natriuretic peptide (NTproBNP) and tumor necrosis factor α (TNF-α) in a large series of patients with hepatitis C associated with mixed cryoglobulinemia (MC+HCV)...AIM: To evaluate serum levels of N-terminal pro-brain natriuretic peptide (NTproBNP) and tumor necrosis factor α (TNF-α) in a large series of patients with hepatitis C associated with mixed cryoglobulinemia (MC+HCV).METHODS: Serum NTproBNP and TNF-α levels were assayed in 50 patients with MC+HCV, and in 50 sex- and age-matched controls. RESULTS: Cryoglobulinemic patients showed signifi cantly higher mean NTproBNP and TNF-α levels than controls (P < 0.001; Mann-Whitney U test). By defining high NTproBNP level as a value higher than 125 pg/mL (the single cut-off point for outpatients under 75 years of age), 30% of MC+HCV and 6% of controls had high NTproBNP (χ2, P < 0.01). With a cut-off point of 300 pg/mL (used to rule out heart failure (HF) in patients under 75 years of age), 8% of MC+HCV and 0 controls had high NTproBNP (χ2, P < 0.04). With a cut-off point of 900 pg/mL (used for ruling in HF in patients aged 50-75 years; such as thepatients of our study), 6% of MC+HCV and 0 controls had high NTproBNP (χ2, P = 0.08).CONCLUSION: The study demonstrates high levels of circulating NTproBNP and TNF-α in MC+HCV patients. The increase of NTproBNP may indicate the presence of a subclinical cardiac dysfunction.展开更多
The summer rainfall over the middle-lower reaches of the Yangtze River valley (YRSR) has been estimated with a multi-linear regression model using principal atmospheric modes derived from a 500 hPa geopotential height...The summer rainfall over the middle-lower reaches of the Yangtze River valley (YRSR) has been estimated with a multi-linear regression model using principal atmospheric modes derived from a 500 hPa geopotential height and a 700 hPa zonal vapor flux over the domain of East Asia and the West Pacific.The model was developed using data from 1958 92 and validated with an independent prediction from 1993 2008.The independent prediction was efficient in predicting the YRSR with a correlation coefficient of 0.72 and a relative root mean square error of 18%.The downscaling model was applied to two general circulation models (GCMs) of Flexible Global Ocean-Atmosphere-Land System Model (FGOALS) and Geophysical Fluid Dynamics Laboratory coupled climate model version 2.1 (GFDL-CM2.1) to project rainfall for present and future climate under B1 and A1B emission scenarios.The downscaled results pro-vided a closer representation of the observation compared to the raw models in the present climate.In addition,compared to the inconsistent prediction directly from dif-ferent GCMs,the downscaled results provided a consistent projection for this half-century,which indicated a clear increase in the YRSR.Under the B1 emission scenario,the rainfall could increase by an average of 11.9% until 2011 25 and 17.2% until 2036 50 from the current state;under the A1B emission scenario,rainfall could increase by an average of 15.5% until 2011 25 and 25.3% until 2036 50 from the current state.Moreover,the increased rate was faster in the following decade (2011 25) than the latter of this half-century (2036 50) under both emissions.展开更多
Through the attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author revealed in this thesis that there are two such econo...Through the attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author revealed in this thesis that there are two such economic phases: An economy where the theory of comparative advantage, proposed by David Ricardo, is applicable, and an economy where the theory is not applicable. The author applied his original approach to prove the validity of Ricardo's comparative advantage theory, and found that the theory can be justified only when a macro economy is in the primal problem phase, where a policy of globalization is effective. It is a necessary and sufficient condition for the theory to be valid. In other words, Ricardo's theory of comparative advantage is not applicable when a macro economy is in the dual problem phase, where a policy of national isolation, instead of that of globalization, is valid. The primal problem phase and the dual problem phase of a macro economy, called in this thesis by the author, are a version of an expression quite common in OR (operations research).展开更多
In the whole earth, people increased dramatically from generation to generation which had created a large scale of broken environment so that people are facing more various types of garbage. Most of garbages are not u...In the whole earth, people increased dramatically from generation to generation which had created a large scale of broken environment so that people are facing more various types of garbage. Most of garbages are not useful and as a matter of fact, they are used to be neglected. Furthermore, many efforts have been conducted to change it by many types of recycled methods. Here, a simple technique is proposed with and without using fires to transform the useless natural or man-made rubbish things to be a superfiber as well as thin film with multitasking applications in human daily life. Since most of earth environment is covered by oceans, here the authors show how the ocean related garbage such as the crab skins, broken coral reefs and beach stones were changed to be superfiber and a multitasking device prototype.展开更多
Mueller said: "The environment has reflection on accounting; different cultural, economic, legal and political backgrounds produce different accounting systems." It's no exception with government accounting. Since...Mueller said: "The environment has reflection on accounting; different cultural, economic, legal and political backgrounds produce different accounting systems." It's no exception with government accounting. Since 1998, China's current budget accounting system has been acting as government accounting. Basically, it fulfilled the needs of relevant government accounting. The government accounting integrated with budget accounting. As time passes by, the current budget accounting can not meet the deepening globalization of the market economy nor the developing economic and political environment in terms of the definition of objectives, choices of basic accounting, offering of accounting information. In recent years, public finance reform, transformation of government functions, the public consciousness and other factors call for higher needs for the new government accounting. The current budget fails to provide enough government accounting information that the public need. In 2011, China started a pilot of performance management and performance budgeting in the country. The efficient use of public funds, the profits, and the effectiveness of public information draw more users' attention. It becomes more important for the govemrnent accounting larovidin~ information of performance evaluation.展开更多
With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantita...With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantitative analysis of the snow cover in the higher Himalayas. In this study, a nonlinear autoregressive exogenous model, an artificial neural network (ANN), was deployed to predict the snow cover in the Kaligandaki river basin for the next 30 years. Observed climatic data, and snow covered area was used to train and test the model that captures the gross features of snow under the current climate scenario. The range of the likely effects of climate change on seasonal snow was assessed in the Himalayas using downscaled temperature and precipitation change projection from - HadCM3, a global circulation model to project future climate scenario, under the AIB emission scenario, which describes a future world of very rapid economic growth with balance use between fossil and non-fossil energy sources. The results show that there is a reduction of 9% to 46% of snow cover in different elevation zones during the considered time period, i.e., 2Oll to 2040. The 4700 m to 52oo m elevation zone is the most affected area and the area higher than 5200 m is the least affected. Overall, however, it is clear from the analysis that seasonal snow in the Kaligandaki basin is likely to be subject to substantialchanges due to the impact of climate change.展开更多
On the basis of two ensemble experiments conducted by a general atmospheric circulation model(Institute of Atmospheric Physics nine-level atmospheric general circulation model coupled with land surface model,hereinaft...On the basis of two ensemble experiments conducted by a general atmospheric circulation model(Institute of Atmospheric Physics nine-level atmospheric general circulation model coupled with land surface model,hereinafter referred to as IAP9L_CoLM),the impacts of realistic Eurasian snow conditions on summer climate predictability were investigated.The predictive skill of sea level pressures(SLP)and middle and upper tropospheric geopotential heights at mid-high latitudes of Eurasia was enhanced when improved Eurasian snow conditions were introduced into the model.Furthermore,the model skill in reproducing the interannual variation and spatial distribution of the surface air temperature(SAT)anomalies over China was improved by applying realistic(prescribed)Eurasian snow conditions.The predictive skill of the summer precipitation in China was low;however,when realistic snow conditions were employed,the predictability increased,illustrating the effectiveness of the application of realistic Eurasian snow conditions.Overall,the results of the present study suggested that Eurasian snow conditions have a significant effect on dynamical seasonal prediction in China.When Eurasian snow conditions in the global climate model(GCM)can be more realistically represented,the predictability of summer climate over China increases.展开更多
The paper describes the application of SDSM (statistical downscaling model) and ANNs (artificial neural networks) models for prediction of the hydrological trend due to the climate-change. The SDSM has been calibr...The paper describes the application of SDSM (statistical downscaling model) and ANNs (artificial neural networks) models for prediction of the hydrological trend due to the climate-change. The SDSM has been calibrated and generated for the possible future scenarios of meteorological variables, which are temperature and rainfall by using GCMs (global climate models). The GCM used is SRES A2. The downscaled meteorological variables corresponding to SDSM were then used as input to the ANNs model calibrated with observed station data to simulate the corresponding future streamflow changes in the sub-catchment of Kurau River. This study has discovered the hydrological trend over the catchment. The projected monthly streamflow has shown a decreasing trend due to the increase in the, mean of temperature for overall months, except the month of August and November.展开更多
The responses of the Arctic Oscillation(AO) to global black carbon(BC) and BC emitted from major regions were compared using the atmospheric general circulation model Geophysical Fluid Dynamics Laboratory(GFDL) atmosp...The responses of the Arctic Oscillation(AO) to global black carbon(BC) and BC emitted from major regions were compared using the atmospheric general circulation model Geophysical Fluid Dynamics Laboratory(GFDL) atmospheric general circulation model(AGCM) Atmospheric Model version 2.1(AM2.1). The results indicated that global BC could induce positive-phase AO responses, characterized by negative responses over the polar cap on 500 h Pa height fields, and zonal mean sea level pressure(SLP) decreasing while zonal wind increasing at 60°, with the opposite responses over midlatitudes. The AO indices distribution also shifted towards positive values. East Asian BC had similar impacts to that of global BC, while the responses to European BC were of opposite sign. South Asian BC and North American BC did not affect the AO significantly. Based on a simple linear assumption, we roughly estimated that the global BC emission increase could explain approximately 5% of the observed positive AO trend of +0.32 per decade during 1960 to 2000.展开更多
The paper is to introduce a computational methodology that is based on ordinary differential equations (ODE) solver for the structural systems adopted by a super tall building in its preliminary design stage so as t...The paper is to introduce a computational methodology that is based on ordinary differential equations (ODE) solver for the structural systems adopted by a super tall building in its preliminary design stage so as to facilitate the designers to adjust the dynamic properties of the adopted structural system. The construction of the study is composed by following aspects. The first aspect is the modelling of a structural system. As a typical example, a mega frame-core-tube structural system adopted by some famous super tall buildings such as Taipei 101 building, Shanghai World financial center, is employed to demonstrate the modelling of a computational model. The second aspect is the establishment of motion equations constituted by a group of ordinary differential equations for the analyses of free vibration and resonant response. The solutions of the motion equations (that constitutes the third aspect) resorted to ODE-solver technique. Finally, some valuable conclusions are summarized.展开更多
Dynamic urban expansion simulation at regional scale is one of the important research methodologies in Land Use/Cover Change (LUCC) and global environmental change influenced by urbanization. However, previous studi...Dynamic urban expansion simulation at regional scale is one of the important research methodologies in Land Use/Cover Change (LUCC) and global environmental change influenced by urbanization. However, previous studies indicate that the single urban expansion simulation for future scenarios at local scale cannot meet the requirements for characterizing and interpreting the interactive mechanisms of regional urbanization and global environmental change. This study constructed a regional Dynamic Urban Expansion Model (Reg-DUEM) suitable for different scenarios by integrating the Artificial Neural Network (ANN) and Cellular Automaton (CA) model. Firstly we analyzed the temporal and spatial characteristics of urban expansion and acquired a prior knowledge rules using land use/cover change datasets of Beijing-Tianjin-Tangshan metropolitan area. The future urban expansion under different scenarios is then simulated based on a baseline model, economic models, policy models and the structural adjustment model. The results indicate that Reg-DUEM has good reliability for a non-linear expansion simulation at regional scale influenced by macro-policies. The simulating results show that future urban expansion patterns from different scenarios of the metropolitan area have the tremendous spatio-temporal differences. Future urban expansion will shift quickly from Beijing metropolis to the periphery of Tianjin and Tangshan city along coastal belt.展开更多
Dynamic Global Vegetation Models(DGVM)are powerful tools for studying complicated ecosystem processes and global changes.This review article synthesizes the developments and applications of the Integrated Biosphere Si...Dynamic Global Vegetation Models(DGVM)are powerful tools for studying complicated ecosystem processes and global changes.This review article synthesizes the developments and applications of the Integrated Biosphere Simulator(IBIS),a DGVM,over the past two decades.IBIS has been used to evaluate carbon,nitrogen,and water cycling in terrestrial ecosystems,vegetation changes,land-atmosphere interactions,land-aquatic system integration,and climate change impacts.Here we summarize model development work since IBIS v2.5,covering hydrology(evapotranspiration,groundwater,lateral routing),vegetation dynamics(plant functional type,land cover change),plant physiology(phenology,photosynthesis,carbon allocation,growth),biogeochemistry(soil carbon and nitrogen processes,greenhouse gas emissions),impacts of natural disturbances(drought,insect damage,fire)and human induced land use changes,and computational improvements.We also summarize IBIS model applications around the world in evaluating ecosystem productivity,carbon and water budgets,water use efficiency,natural disturbance effects,and impacts of climate change and land use change on the carbon cycle.Based on this review,visions of future cross-scale,cross-landscape and cross-system model development and applications are discussed.展开更多
基金National Natural Science Foundation of China (40233031)
文摘Due to the decrease in grid size associated with the convergence of meridians toward the poles inspherical coordinates, the time steps in many global climate models with finite-difference method are restrictedto be unpleasantly small. To overcome the problem, a reduced grid is introduced to LASG/IAP world oceangeneral circulation models. The reduced grid is implemented successfully in the coarser resolutions versionmodel L30T63 at first. Then, it is carried out in the improved version model LICOM with finer resolutions. Inthe experiment with model L30T63, under time step unchanged though, execution time per single model run isshortened significantly owing to the decrease of grid number and filtering execution in high latitudes. Resultsfrom additional experiments with L30T63 show that the time step of integration can be quadrupled at most inreduced grid with refinement ratio 3. In the experiment with model LICOM and with the model’s original timestep unchanged, the model covered area is extended to the whole globe from its original case with the grid pointof North Pole considered as an isolated island and the results of experiment are shown to be acceptable.
基金supported by the National Basic Research Program of China[grant number 2012CB955202]the National Natural Science Foundation of China[grant numbers 41005040 and 41023002]the R&D Special Fund for Public Welfare Industry(Meteorology)[grant number GYHY201506012]
文摘The interdecadal circumglobal teleconnection (ID-CGT) pattern is the dominant circulation mode over the NH during boreal summer on the interdecadal time scale. Its temporal evolution is synchronous with that of the Atlantic Multidecadal Oscillation (AMO). In this study, through analyzing the results of sensitivity experiments using five AGCMs driven by specified AMO-related SST anomalies (SSTAs) in the North Atlantic, the authors investigate whether the ID-CGT is excited by the AMO. Two out of the five models simulate the barotropic stationary wave pattern located along the westerly jet, suggesting that the ID-CGT pattern should be excited, at least partially, by the AMO- related SSTAs. Model results suggest that the ID-CGT pattern plays a role in linking the AMO and NH summer land SAT perturbations on the interdecadal time scale.
基金supported jointly by the National Basic Research Program of China(Grant No.2012CB956203)the Strategic Priority Research Program-Climate Change:Carbon Budget and Relevant Issues of the Chinese Academy of Sciences(Grant No.XDA05090207)+1 种基金the Special Fund for Meteorological Research in the Public Interest(Grant No.GYHY201006023)the National Natural Science Foundation of China(General Program,Grant No.40905042)
文摘Two numerical experiments were performed by using the Community Atmosphere Model version 3 (CAM3) with different sea ice datasets to assess the con- tribution of the decline of Arctic sea ice to warming in the Northern Hemisphere. One observed sea ice cover data; experiment was driven by for the other one, the authors used the sea ice data of the 4xCO2 scenario simulated by the fourth-generation European Centre Hamburg atmos- pheric general circulation Model of Istituto Nazionale di Geofisica e Vulcanologia, Italy (1NGV ECHAM4). The comparison of the two experiments indicates that the de- cline of the Arctic sea ice leads to a dramatic wanning over the high latitudes of the Northern Hemisphere, char- acterized by a maximum warming of more than 26~C over the Arctic region. The significant warming is closely re- lated to the enhanced atmospheric heat source. A 40-60 W m-2 increase in the apparent heat source was simulated in winter due to the decline of Arctic sea ice. In contrast, no significant change was found in the atmospheric ap- parent heat source in summer. As a result, the summer temperature change induced by the decline of Arctic sea ice appears to be weak. This study suggests that accurate sea ice cover data is crucial for future climate projection of air temperature in high latitudes.
文摘AIM: To evaluate serum levels of N-terminal pro-brain natriuretic peptide (NTproBNP) and tumor necrosis factor α (TNF-α) in a large series of patients with hepatitis C associated with mixed cryoglobulinemia (MC+HCV).METHODS: Serum NTproBNP and TNF-α levels were assayed in 50 patients with MC+HCV, and in 50 sex- and age-matched controls. RESULTS: Cryoglobulinemic patients showed signifi cantly higher mean NTproBNP and TNF-α levels than controls (P < 0.001; Mann-Whitney U test). By defining high NTproBNP level as a value higher than 125 pg/mL (the single cut-off point for outpatients under 75 years of age), 30% of MC+HCV and 6% of controls had high NTproBNP (χ2, P < 0.01). With a cut-off point of 300 pg/mL (used to rule out heart failure (HF) in patients under 75 years of age), 8% of MC+HCV and 0 controls had high NTproBNP (χ2, P < 0.04). With a cut-off point of 900 pg/mL (used for ruling in HF in patients aged 50-75 years; such as thepatients of our study), 6% of MC+HCV and 0 controls had high NTproBNP (χ2, P = 0.08).CONCLUSION: The study demonstrates high levels of circulating NTproBNP and TNF-α in MC+HCV patients. The increase of NTproBNP may indicate the presence of a subclinical cardiac dysfunction.
基金supported by the National Basic Research Program of China (Grant No.2010CB950400)the National Natural Science Foundation of China (Key Project,Grant No.41030961)the Australia-China Bilateral Climate Change Partnerships Program of the Australian Department of Climate Change
文摘The summer rainfall over the middle-lower reaches of the Yangtze River valley (YRSR) has been estimated with a multi-linear regression model using principal atmospheric modes derived from a 500 hPa geopotential height and a 700 hPa zonal vapor flux over the domain of East Asia and the West Pacific.The model was developed using data from 1958 92 and validated with an independent prediction from 1993 2008.The independent prediction was efficient in predicting the YRSR with a correlation coefficient of 0.72 and a relative root mean square error of 18%.The downscaling model was applied to two general circulation models (GCMs) of Flexible Global Ocean-Atmosphere-Land System Model (FGOALS) and Geophysical Fluid Dynamics Laboratory coupled climate model version 2.1 (GFDL-CM2.1) to project rainfall for present and future climate under B1 and A1B emission scenarios.The downscaled results pro-vided a closer representation of the observation compared to the raw models in the present climate.In addition,compared to the inconsistent prediction directly from dif-ferent GCMs,the downscaled results provided a consistent projection for this half-century,which indicated a clear increase in the YRSR.Under the B1 emission scenario,the rainfall could increase by an average of 11.9% until 2011 25 and 17.2% until 2036 50 from the current state;under the A1B emission scenario,rainfall could increase by an average of 15.5% until 2011 25 and 25.3% until 2036 50 from the current state.Moreover,the increased rate was faster in the following decade (2011 25) than the latter of this half-century (2036 50) under both emissions.
文摘Through the attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author revealed in this thesis that there are two such economic phases: An economy where the theory of comparative advantage, proposed by David Ricardo, is applicable, and an economy where the theory is not applicable. The author applied his original approach to prove the validity of Ricardo's comparative advantage theory, and found that the theory can be justified only when a macro economy is in the primal problem phase, where a policy of globalization is effective. It is a necessary and sufficient condition for the theory to be valid. In other words, Ricardo's theory of comparative advantage is not applicable when a macro economy is in the dual problem phase, where a policy of national isolation, instead of that of globalization, is valid. The primal problem phase and the dual problem phase of a macro economy, called in this thesis by the author, are a version of an expression quite common in OR (operations research).
文摘In the whole earth, people increased dramatically from generation to generation which had created a large scale of broken environment so that people are facing more various types of garbage. Most of garbages are not useful and as a matter of fact, they are used to be neglected. Furthermore, many efforts have been conducted to change it by many types of recycled methods. Here, a simple technique is proposed with and without using fires to transform the useless natural or man-made rubbish things to be a superfiber as well as thin film with multitasking applications in human daily life. Since most of earth environment is covered by oceans, here the authors show how the ocean related garbage such as the crab skins, broken coral reefs and beach stones were changed to be superfiber and a multitasking device prototype.
文摘Mueller said: "The environment has reflection on accounting; different cultural, economic, legal and political backgrounds produce different accounting systems." It's no exception with government accounting. Since 1998, China's current budget accounting system has been acting as government accounting. Basically, it fulfilled the needs of relevant government accounting. The government accounting integrated with budget accounting. As time passes by, the current budget accounting can not meet the deepening globalization of the market economy nor the developing economic and political environment in terms of the definition of objectives, choices of basic accounting, offering of accounting information. In recent years, public finance reform, transformation of government functions, the public consciousness and other factors call for higher needs for the new government accounting. The current budget fails to provide enough government accounting information that the public need. In 2011, China started a pilot of performance management and performance budgeting in the country. The efficient use of public funds, the profits, and the effectiveness of public information draw more users' attention. It becomes more important for the govemrnent accounting larovidin~ information of performance evaluation.
文摘With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantitative analysis of the snow cover in the higher Himalayas. In this study, a nonlinear autoregressive exogenous model, an artificial neural network (ANN), was deployed to predict the snow cover in the Kaligandaki river basin for the next 30 years. Observed climatic data, and snow covered area was used to train and test the model that captures the gross features of snow under the current climate scenario. The range of the likely effects of climate change on seasonal snow was assessed in the Himalayas using downscaled temperature and precipitation change projection from - HadCM3, a global circulation model to project future climate scenario, under the AIB emission scenario, which describes a future world of very rapid economic growth with balance use between fossil and non-fossil energy sources. The results show that there is a reduction of 9% to 46% of snow cover in different elevation zones during the considered time period, i.e., 2Oll to 2040. The 4700 m to 52oo m elevation zone is the most affected area and the area higher than 5200 m is the least affected. Overall, however, it is clear from the analysis that seasonal snow in the Kaligandaki basin is likely to be subject to substantialchanges due to the impact of climate change.
基金supported by the Special Public Sector Research of Meteorology (Grant No. GYHY200906018)the National Basic Research Program of China (Grant No. 2009CB421407)the National Key Technologies R&D Program of China (Grant No. 2007BAC29B03)
文摘On the basis of two ensemble experiments conducted by a general atmospheric circulation model(Institute of Atmospheric Physics nine-level atmospheric general circulation model coupled with land surface model,hereinafter referred to as IAP9L_CoLM),the impacts of realistic Eurasian snow conditions on summer climate predictability were investigated.The predictive skill of sea level pressures(SLP)and middle and upper tropospheric geopotential heights at mid-high latitudes of Eurasia was enhanced when improved Eurasian snow conditions were introduced into the model.Furthermore,the model skill in reproducing the interannual variation and spatial distribution of the surface air temperature(SAT)anomalies over China was improved by applying realistic(prescribed)Eurasian snow conditions.The predictive skill of the summer precipitation in China was low;however,when realistic snow conditions were employed,the predictability increased,illustrating the effectiveness of the application of realistic Eurasian snow conditions.Overall,the results of the present study suggested that Eurasian snow conditions have a significant effect on dynamical seasonal prediction in China.When Eurasian snow conditions in the global climate model(GCM)can be more realistically represented,the predictability of summer climate over China increases.
文摘The paper describes the application of SDSM (statistical downscaling model) and ANNs (artificial neural networks) models for prediction of the hydrological trend due to the climate-change. The SDSM has been calibrated and generated for the possible future scenarios of meteorological variables, which are temperature and rainfall by using GCMs (global climate models). The GCM used is SRES A2. The downscaled meteorological variables corresponding to SDSM were then used as input to the ANNs model calibrated with observed station data to simulate the corresponding future streamflow changes in the sub-catchment of Kurau River. This study has discovered the hydrological trend over the catchment. The projected monthly streamflow has shown a decreasing trend due to the increase in the, mean of temperature for overall months, except the month of August and November.
基金jointly supported by the National Basic Research Program of China(973 Program,2015CB453202 and 2012CB417403)the National Natural Science Foundation of China(41421004)
文摘The responses of the Arctic Oscillation(AO) to global black carbon(BC) and BC emitted from major regions were compared using the atmospheric general circulation model Geophysical Fluid Dynamics Laboratory(GFDL) atmospheric general circulation model(AGCM) Atmospheric Model version 2.1(AM2.1). The results indicated that global BC could induce positive-phase AO responses, characterized by negative responses over the polar cap on 500 h Pa height fields, and zonal mean sea level pressure(SLP) decreasing while zonal wind increasing at 60°, with the opposite responses over midlatitudes. The AO indices distribution also shifted towards positive values. East Asian BC had similar impacts to that of global BC, while the responses to European BC were of opposite sign. South Asian BC and North American BC did not affect the AO significantly. Based on a simple linear assumption, we roughly estimated that the global BC emission increase could explain approximately 5% of the observed positive AO trend of +0.32 per decade during 1960 to 2000.
基金Acknowledgment The research work was financially supported both by the Natural Science Foundation of China (51178164) and the Priority Discipline Foundation of Henan Province (507909).
文摘The paper is to introduce a computational methodology that is based on ordinary differential equations (ODE) solver for the structural systems adopted by a super tall building in its preliminary design stage so as to facilitate the designers to adjust the dynamic properties of the adopted structural system. The construction of the study is composed by following aspects. The first aspect is the modelling of a structural system. As a typical example, a mega frame-core-tube structural system adopted by some famous super tall buildings such as Taipei 101 building, Shanghai World financial center, is employed to demonstrate the modelling of a computational model. The second aspect is the establishment of motion equations constituted by a group of ordinary differential equations for the analyses of free vibration and resonant response. The solutions of the motion equations (that constitutes the third aspect) resorted to ODE-solver technique. Finally, some valuable conclusions are summarized.
基金The Young Scientist Fund of National Natural Science Foundation of China, No.40901224 National Basic Research Program of China, No.2010CB950900+2 种基金 Opening Foundation of State Key Laboratory of Remote Sensing Science, No.2009KFJJ005 Opening Foundation of State Key Lab of Resources and Environmental Information System, No.A0725 Swedish Research Links, No.2006-24724-44416-13
文摘Dynamic urban expansion simulation at regional scale is one of the important research methodologies in Land Use/Cover Change (LUCC) and global environmental change influenced by urbanization. However, previous studies indicate that the single urban expansion simulation for future scenarios at local scale cannot meet the requirements for characterizing and interpreting the interactive mechanisms of regional urbanization and global environmental change. This study constructed a regional Dynamic Urban Expansion Model (Reg-DUEM) suitable for different scenarios by integrating the Artificial Neural Network (ANN) and Cellular Automaton (CA) model. Firstly we analyzed the temporal and spatial characteristics of urban expansion and acquired a prior knowledge rules using land use/cover change datasets of Beijing-Tianjin-Tangshan metropolitan area. The future urban expansion under different scenarios is then simulated based on a baseline model, economic models, policy models and the structural adjustment model. The results indicate that Reg-DUEM has good reliability for a non-linear expansion simulation at regional scale influenced by macro-policies. The simulating results show that future urban expansion patterns from different scenarios of the metropolitan area have the tremendous spatio-temporal differences. Future urban expansion will shift quickly from Beijing metropolis to the periphery of Tianjin and Tangshan city along coastal belt.
基金The Key Project of National Natural Science Foundation of China(41930651)The National Natural Science Foundation of China(41871334)。
文摘Dynamic Global Vegetation Models(DGVM)are powerful tools for studying complicated ecosystem processes and global changes.This review article synthesizes the developments and applications of the Integrated Biosphere Simulator(IBIS),a DGVM,over the past two decades.IBIS has been used to evaluate carbon,nitrogen,and water cycling in terrestrial ecosystems,vegetation changes,land-atmosphere interactions,land-aquatic system integration,and climate change impacts.Here we summarize model development work since IBIS v2.5,covering hydrology(evapotranspiration,groundwater,lateral routing),vegetation dynamics(plant functional type,land cover change),plant physiology(phenology,photosynthesis,carbon allocation,growth),biogeochemistry(soil carbon and nitrogen processes,greenhouse gas emissions),impacts of natural disturbances(drought,insect damage,fire)and human induced land use changes,and computational improvements.We also summarize IBIS model applications around the world in evaluating ecosystem productivity,carbon and water budgets,water use efficiency,natural disturbance effects,and impacts of climate change and land use change on the carbon cycle.Based on this review,visions of future cross-scale,cross-landscape and cross-system model development and applications are discussed.