| The distribution and conversion of surface energy in the Antarctica not only plays an important role in local weather and climate change,but also affects the world through the atmospheric circulation.However,due to the harsh natural environment in the Antarctica and the limit of relatively backward technical means,it is very difficult to carry out the observation experiments,resulting in the lack of observation data,especially the turbulent sensible heat and latent fluxes accurately measured by eddy covariance method in the surface energy balance equation.On the other hand,due to the low coverage of eddy covariance observation system,there are still not enough data can be directly applied in weather and climate models.Therefore,it is very important to improve the applicability of near-surface turbulent flux parameterization method based on Monin-Obukhov similarity theory in the Antarctica.Furthermore,as an important part of the Antarctic climate system,the generation and dissipation of landfast sea ice is closely related to the surface energy distribution.Based on the data collected at the land and sea ice observation sites near the Zhongshan station,this paper analyzes the characteristics of surface energy budget in this region,gives the best near-surface turbulent fluxes parameterization scheme,and tests the calculation results of each parameterization schemes in the HIGHTSI(High-resolution thermodynamic snow/ice)model and the sensitivity of deviation of parameterization result to the simulation of sea ice thickness.The main concludes are summarized as follows:(1)The analysis of the characteristics of surface energy budget shows that there was no significant difference between the land and sea ice surface in winter.The surface lost energy through net radiation and latent heat fluxes,and the net radiation flux was the main part of lost energy,while the lost energy was supplemented by sensible heat and subsurface conductive heat fluxes.However,with the increase of solar radiation,the difference of surface albedo between land and sea ice resulted in the enhancement of the difference of net radiation.In spring,the net radiation of sea ice surface was much smaller than that of land surface,which led to the different distribution of sensible heat flux and surface residual energy.(2)Based on the analysis of gradient observation data,it is shown that the stability correction functions of CB05 under stable stratification and Bu71 under unstable stratification were more applicable in this area.The calculation results of aerodynamic(thermal)roughness length indicated that the mean values for land and sea ice surface were 3.9×10-3 m(1.8×10-4 m)and 1.9×10-3 m(3.7×10-5 m)respectively.At the land obserevation site,when the surface was covered by snow,the thermal roughness length calculated by the A87 scheme was the best under stable stratification,but the deviation between the A87 scheme and observation under the near-neutral and unstable stratification was significant.Hence,based on the equation form of Z95scheme,a new k B-1 parameterization scheme was proposed.At the sea ice obserevation site,the thermal roughness length calculated by the A87 scheme was consistent with observation.In addition,the applicability evaluation of four non-iterative schemes shows that each non-iterative scheme could calculate the turbulent momentum flux well,but the deviation of calculated sensible heat flux was relatively larger.Compared with other shcemes,the standardization error of sensible heat fluxed calculated by Wo12 scheme and Li14&15 scheme were smaller.(3)By analyzing the result of various parameterization schemes in the HIGHTSI model and the sensitivity of deviation of parameterizated result to the simulation of sea ice thickness,it can be found that the parameterized result of surface albedo and atmospheric longwave radiation were relatively poor,and the simulation of sea ice thickness was sensitive to the deviation of parameterized atmospheric longwave radiation.Additionally,the accuracy of simulated result was greatly improved by improving the description of oceanic heat flux in the HIGHTSI model. |
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