Measurements of turbulence transfer in the near-surface layer over the Antarctic sea-ice surface from April through November in 2016

Abstract

The surface energy budget over the Antarctic sea ice from 8 April 2016 through 26 November 2016 are presented. From April to October, Sensible heat flux (SH) and subsurface conductive heat flux (G) were the heat source of surface while latent heat flux (LE) and net radiation flux (R n ) were the heat sink of surface. Our results showed larger downward SH (due to the warmer air in our site) and upward LE (due to the drier air and higher wind speed in our site) compared with SHEBA data. However, the values of SH in N-ICE2015 campaign, which located at a zone with stronger winds and more advection of heat in the Arctic, were comparable to our results under clear skies. The values of aerodynamic roughness length (z0m) and scalar roughness length for temperature (z0h), being 1.9 × 10−3 m and 3.7 × 10−5 m, were suggested in this study. It is found that snow melting might increase z0m. Our results also indicate that the value of log(z0h/z0m) was related to the stability of stratification. In addition, several representative parameterization schemes for z0h have been tested and a couple of schemes were found to make a better performance.

Evidence of Strong Flux Underestimation by Bulk Parametrizations During Drifting and Blowing Snow

“…The roughness lengths for humidity and temperature were calculated as a function of the friction velocity and z 0 according to the parametrization of Andreas (1987). Although measurement uncertainties make it difficult to validate this parametrization, a couple of studies support the plausibility of the parametrization at snow-covered sites with z 0 < 10 −3 m (Smeets and van den Broeke 2008; Andreas et al 2010;Park et al 2010;Vignon et al 2017;Liu et al 2020).…”

The sensitivity of parameterization schemes in thermodynamic modeling of the landfast sea ice in Prydz Bay, East Antarctica

“…The z 0m calculated by Banke and others (1980) is 1.42 × 10 −4 m, and the z 0h ranges from 1.1 × 10 −8 to 1.6 × 10 −4 m according to Andreas (1987). However, Liu and others (2020) analyzed the same dataset employed in this study and revealed that the values of z 0m and z 0h should be 1.9 × 10 −3 and 3.7 × 10 −5 m, respectively. Hence, the values of z 0m and z 0h in the HIGHTSI model are revised according to Liu and others (2020).…”

“…However, Liu and others (2020) analyzed the same dataset employed in this study and revealed that the values of z 0m and z 0h should be 1.9 × 10 −3 and 3.7 × 10 −5 m, respectively. Hence, the values of z 0m and z 0h in the HIGHTSI model are revised according to Liu and others (2020). Figures 9a, b compare the parameterized Q h and Q le against the corresponding observations, revealing that Q h is overestimated by the HIGHTSI model, whereas Q le is underestimated.…”

“…The key technical specifications and installation information of these instruments are summarized in Table 1. The meteorological data were first published in Liu and others (2020), and the data processing and quality control procedures were the same as those in Liu and others (2020), while the sea-ice data are first presented in this study. We consider the positive heat fluxes as the surface or sea-ice bottom gains the energy, while the negative heat fluxes indicate the surface or bottom loses energy in this study.…”

“…In 2016, comprehensive observations were conducted over the landfast sea ice near Zhongshan station. High-quality datasets, especially turbulence fluxes over the sea ice, have been collected for the first time at this location (Liu and others, 2020). These datasets provide an excellent opportunity to evaluate the thermodynamic parameterization schemes in numerical models.…”