The future change of September Arctic sea-ice volume,simulated by 30 state-of-the-art climate models from the Coupled Model Intercomparison Project Phase 5(CMIP5),is examined,which depends on both ice extent and ice...The future change of September Arctic sea-ice volume,simulated by 30 state-of-the-art climate models from the Coupled Model Intercomparison Project Phase 5(CMIP5),is examined,which depends on both ice extent and ice thickness.In comparison with the September sea-ice extent,the September sea-ice volume has larger spread in the historical simulation but faster convergence in the projection simulation,especially in the context of increasing greenhouse gas emissions.This indicates that the ice volume might be more sensitive to external forcings than the ice extent.Using the averaged projection of those climate models from the 30 CMIP5 models that can better reflect the ‘observed' sea-ice volume climatology and variability,it is shown that the September sea ice volume will decrease to ~3000 km3 in the early 2060 s,and then level off under a medium-mitigation scenario.However,it will drop to ~3000 km3 in the early 2040 s and reach a near-zero ice volume in the mid-2070 s under a high-emission scenario.With respect to the historical condition,the reduction of the ice volume,associated with increasing greenhouse gas emissions,is more rapid than that of the ice extent during the twenty-first century.展开更多
The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to assess the impacts of climate change and deforestation on stream discharge and sediment yield from Phu Luong watershed in Nort...The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to assess the impacts of climate change and deforestation on stream discharge and sediment yield from Phu Luong watershed in Northern Viet Nam. Among the three climate change scenarios B 1, B2, and A2, representing low, medium, and high levels of greenhouse gas emission, respectively were set up for Viet Nam, the B2 scenario was selected for this study. Two land use scenarios (S1-2030 and $2-2050) were formulated combination with climate change in WSAT simulation. In B2 climate change scenario, mean temperature increases 0.7℃(2030) and 1.3 ℃ (2050); annual rainfall increases 2.1% (2030) and 3.80% (2050) respect to baseline scenario. The results show that the stream discharge is likely to increase in the future during the wet season with increasing threats of sedimentation.展开更多
Laser-induced incandescence (LII) has received increasing attention as a potentially powerful technique for in-situ measuring of the volume fraction and primary size of soot particles in combustion systems. In this st...Laser-induced incandescence (LII) has received increasing attention as a potentially powerful technique for in-situ measuring of the volume fraction and primary size of soot particles in combustion systems. In this study, a 3D Monte Carlo simulation combined with a Mie equation was developed to analyze the influence of spectral absorption and scattering on the measured LII flux emitted by soot particles. This paper represents a first attempt to analyze soot measurement using the LII technique in coal combustion products. The combustion products of gases (CO2, N2), soot, and fly-ash particles, present between the location of laser-excited soot and the LII flux receiver. The simulation results indicated that an almost Beer-Lambert exponential decrease in LII flux occurred with an increase in the volume fraction of soot particles, while a nearly linear decrease occurred with an increase in the volume fraction of fly-ash particles. The results also showed that scattering effects of both soot and fly-ash particles on the LII flux could be neglected. Compared with the absorption of gases, a decrease of 20% of LII flux was observed with soot particles, and a decrease of 10% with fly-ash particles.展开更多
基金supported by the National Natural Science Foundation of China[grant numbers 41305097 and 41176169]the National Basic Research Program of China[973 program,grant number 2011CB309704]
文摘The future change of September Arctic sea-ice volume,simulated by 30 state-of-the-art climate models from the Coupled Model Intercomparison Project Phase 5(CMIP5),is examined,which depends on both ice extent and ice thickness.In comparison with the September sea-ice extent,the September sea-ice volume has larger spread in the historical simulation but faster convergence in the projection simulation,especially in the context of increasing greenhouse gas emissions.This indicates that the ice volume might be more sensitive to external forcings than the ice extent.Using the averaged projection of those climate models from the 30 CMIP5 models that can better reflect the ‘observed' sea-ice volume climatology and variability,it is shown that the September sea ice volume will decrease to ~3000 km3 in the early 2060 s,and then level off under a medium-mitigation scenario.However,it will drop to ~3000 km3 in the early 2040 s and reach a near-zero ice volume in the mid-2070 s under a high-emission scenario.With respect to the historical condition,the reduction of the ice volume,associated with increasing greenhouse gas emissions,is more rapid than that of the ice extent during the twenty-first century.
文摘The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to assess the impacts of climate change and deforestation on stream discharge and sediment yield from Phu Luong watershed in Northern Viet Nam. Among the three climate change scenarios B 1, B2, and A2, representing low, medium, and high levels of greenhouse gas emission, respectively were set up for Viet Nam, the B2 scenario was selected for this study. Two land use scenarios (S1-2030 and $2-2050) were formulated combination with climate change in WSAT simulation. In B2 climate change scenario, mean temperature increases 0.7℃(2030) and 1.3 ℃ (2050); annual rainfall increases 2.1% (2030) and 3.80% (2050) respect to baseline scenario. The results show that the stream discharge is likely to increase in the future during the wet season with increasing threats of sedimentation.
基金Project supported by the National Natural Science Foundation of China (No. 60534030)the National Hi-Tech Research and Development Program (973) (No. 2009CB219802)the Program of Introducing Talents of Discipline to University (No. B08026),China
文摘Laser-induced incandescence (LII) has received increasing attention as a potentially powerful technique for in-situ measuring of the volume fraction and primary size of soot particles in combustion systems. In this study, a 3D Monte Carlo simulation combined with a Mie equation was developed to analyze the influence of spectral absorption and scattering on the measured LII flux emitted by soot particles. This paper represents a first attempt to analyze soot measurement using the LII technique in coal combustion products. The combustion products of gases (CO2, N2), soot, and fly-ash particles, present between the location of laser-excited soot and the LII flux receiver. The simulation results indicated that an almost Beer-Lambert exponential decrease in LII flux occurred with an increase in the volume fraction of soot particles, while a nearly linear decrease occurred with an increase in the volume fraction of fly-ash particles. The results also showed that scattering effects of both soot and fly-ash particles on the LII flux could be neglected. Compared with the absorption of gases, a decrease of 20% of LII flux was observed with soot particles, and a decrease of 10% with fly-ash particles.