2026-06-29T03:12:45Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/243902023-08-28T19:58:15Zcom_20.500.14352_14col_20.500.14352_15

00925njm 22002777a 4500 dc Román Cascón, Carlos author Yagüe Anguis, Carlos author Steeneveld, Gert-Jan author Sastre Marugán, Mariano author Arrillaga, Jon Ander author Maqueda Burgos, Gregorio author 2016-03-15 Fog-top height (fog thickness) is very useful information for aircraft maneuvers, data assimilation/validation of Numerical Weather Prediction models or nowcasting of fog dissipation. This variable is usually difficult to determine, since the fog-layer top cannot be observed from the surface. In some cases, satellite data, ground remote sensing instruments or atmospheric soundings are used to provide approximations of fog-top height. These instruments are expensive and their data not always available. In this work, two different methods for the estimation of fog-top height from field measurements are evaluated from the statistical analysis of several radiation-fog events at two research facilities. Firstly, surface friction velocity and buoyancy flux are here presented as potential indicators of fog thickness, since a linear correlation between fog thickness and surface turbulence is found at both sites. An operational application of this method can provide a continuous estimation of fog-top height with the deployment of a unique sonic anemometer at surface. Secondly, the fog-top height estimation based on the turbulent homogenisation within well-mixed fog (an adiabatic temperature profile) is evaluated. The latter method provides a high percentage of correctly-estimated fog-top heights for well-mixed radiation fog, considering the temperature difference between different levels of the fog. However, it is not valid for shallow fog (~ less than 50 m depth), since in this case, the weaker turbulence within the fog is not able to erode the surface-based temperature inversion and to homogenise the fog layer. 0169-8095 10.1016/j.atmosres.2015.11.016 https://hdl.handle.net/20.500.14352/24390 http://dx.doi.org/10.1016/j.atmosres.2015.11.016 http://www.sciencedirect.com/science/ Estimating fog-top height through near-surface micrometeorological measurements