In this study, we mainly introduce two salinity parameterization schemes used in Sea Ice Simulator (SIS), that is, isosaline scheme and salinity profile scheme. Comparing the equation of isosaline scheme with that o...In this study, we mainly introduce two salinity parameterization schemes used in Sea Ice Simulator (SIS), that is, isosaline scheme and salinity profile scheme. Comparing the equation of isosaline scheme with that of salinity profile scheme, we found that there was one different term between the two schemes named the salinity different term. The thermodynamic effect of the salinity difference term on sea ice thickness and sea ice concentration showed that: in the freezing processes from November to next May, the sea ice temperature could rise on the influence of the salinity difference term and restrain sea ice freezing; at the first melting phase from June to August, the upper ice melting rate was faster than the lower ice melting rate. Then sea ice temperature could rise and accelerate the sea ice melting; at the second melting phase from September to October, the upper ice melting rate was slower than the lower ice melting rate, then sea ice temperature could decrease and restrain sea ice melting. However, the effect of the salinity difference term on the sea ice thickness and sea ice concentration was weak. To analyze the impacts of the salinity different term on Arctic sea ice thickness and sea ice concentration, we also designed several experiments by introducing the two salinity parameterizations to the ice-ocean coupled model, Modular Ocean Model (MOM4), respectively. The simulated results confirmed the previous results of formula derivation.展开更多
The heterogeneous hydrolysis of dinitrogen pentoxide(N2O5)plays an important role in regulating NOx.The N2O5 uptake coefficient,γ(N2O5),was determined using an iterative box model that was constrained to observationa...The heterogeneous hydrolysis of dinitrogen pentoxide(N2O5)plays an important role in regulating NOx.The N2O5 uptake coefficient,γ(N2O5),was determined using an iterative box model that was constrained to observational data obtained in suburban Beijing from February to March 2016.The box model determined 2289 individualγ(N2O5)values that varied from<0.001 to 0.02 with an average value of 0.0046±0.0039(and a median value of 0.0032).We found the derived winterγ(N2O5)values in Beijing were relatively low as compared to values reported in previous field studies conducted during winter in Hong Kong(average value of 0.014)and the eastern U.S.coast(median value of 0.0143).In our study,field evidence of the suppression ofγ(N2O5)values due to pNO3-content,organics and the enhancement by aerosol liquid water content(ALWC)is in line with previous laboratory study results.Low ALWC,high pNO3-content,and particle morphology(inorganic core with an organic shell)accounted for the lowγ(N2O5)values in the North China Plain(NCP)during wintertime.The field-derivedγ(N2O5)values are well reproduced by a revised parameterization method,which includes the aerosol size distribution,ALWC,nitrate and organic coating,suggesting the feasibility of comprehensive parameterization in the NCP during wintertime.展开更多
基金supported by the National Natural Science Foundation of China(No.41075030,41106004,41106159 and 41206013)the Ocean Public Welfare Science Research Project,State Oceanic Administration,People's Republic of China(No.201005019)
文摘In this study, we mainly introduce two salinity parameterization schemes used in Sea Ice Simulator (SIS), that is, isosaline scheme and salinity profile scheme. Comparing the equation of isosaline scheme with that of salinity profile scheme, we found that there was one different term between the two schemes named the salinity different term. The thermodynamic effect of the salinity difference term on sea ice thickness and sea ice concentration showed that: in the freezing processes from November to next May, the sea ice temperature could rise on the influence of the salinity difference term and restrain sea ice freezing; at the first melting phase from June to August, the upper ice melting rate was faster than the lower ice melting rate. Then sea ice temperature could rise and accelerate the sea ice melting; at the second melting phase from September to October, the upper ice melting rate was slower than the lower ice melting rate, then sea ice temperature could decrease and restrain sea ice melting. However, the effect of the salinity difference term on the sea ice thickness and sea ice concentration was weak. To analyze the impacts of the salinity different term on Arctic sea ice thickness and sea ice concentration, we also designed several experiments by introducing the two salinity parameterizations to the ice-ocean coupled model, Modular Ocean Model (MOM4), respectively. The simulated results confirmed the previous results of formula derivation.
基金supported by the National Natural Science Foundation of China(21976006,41907185,91844301,91544225)Beijing Natural Science Foundation,China(JQ19031)China Postdoctoral Science Foundation(2018M641095,2019T120023)。
文摘The heterogeneous hydrolysis of dinitrogen pentoxide(N2O5)plays an important role in regulating NOx.The N2O5 uptake coefficient,γ(N2O5),was determined using an iterative box model that was constrained to observational data obtained in suburban Beijing from February to March 2016.The box model determined 2289 individualγ(N2O5)values that varied from<0.001 to 0.02 with an average value of 0.0046±0.0039(and a median value of 0.0032).We found the derived winterγ(N2O5)values in Beijing were relatively low as compared to values reported in previous field studies conducted during winter in Hong Kong(average value of 0.014)and the eastern U.S.coast(median value of 0.0143).In our study,field evidence of the suppression ofγ(N2O5)values due to pNO3-content,organics and the enhancement by aerosol liquid water content(ALWC)is in line with previous laboratory study results.Low ALWC,high pNO3-content,and particle morphology(inorganic core with an organic shell)accounted for the lowγ(N2O5)values in the North China Plain(NCP)during wintertime.The field-derivedγ(N2O5)values are well reproduced by a revised parameterization method,which includes the aerosol size distribution,ALWC,nitrate and organic coating,suggesting the feasibility of comprehensive parameterization in the NCP during wintertime.