The influence of the spatial distribution of leads and ice floes on the atmospheric boundary layer over fragmented sea ice
Marta Wenta , Agnieszka Herman
AbstractThe response of the atmospheric boundary layer (ABL) to subgrid-scale variations of sea ice properties and fracturing is poorly understood and not taken into account in mesoscale Numerical Weather Prediction (NWP) model parametrizations. In this paper we analyze three-dimensional air circulation within the ABL over fragmented sea ice. A series of idealized high-resolution simulations with the Weather Research and Forecasting (WRF) model is performed for several spatial distributions of ice floes and leads for two values of sea ice concentration (0.5 and 0.9) and several ambient wind speed profiles. The results show that the convective circulation within the ABL is sensitive to the subgrid-scale spatial distribution of sea ice. Considerable variability of several domain-averaged quantities – cloud liquid water content, surface turbulent heat flux (THF) – is found for different arrangements of floes. Moreover, the organized structure of air circulation leads to spatial covariance of variables characterizing the ABL. Based on the example of THF, it is demonstrated that this covariance may lead to substantial errors when THF values are estimated from area-averaged quantities, as it is done in mesoscale NWP models. This suggests the need for developing suitable parametrizations of ABL effects related to subgrid-scale sea ice features for these models.
|Journal series||Annals of Glaciology, ISSN 0260-3055, (A 30 pkt)|
|No||76, p. 2|
|Publication size in sheets||0.85|
|Keywords in English||atmosphere/ice/ocean interactions, ice/atmosphere interactions, sea ice|
|License||Other; published final; ; with publication|
|Score|| = 25.0, 04-04-2019, ArticleFromJournal|
= 30.0, 04-04-2019, ArticleFromJournal
|Publication indicators||= 0; : 2017 = 0.755; : 2017 = 2.761 (2) - 2017=2.323 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.