Evaluation of the Planetary Boundary Layer Parameterizations of WRF Model in North Northeast Coast at Brazil

Abstract This work aims to evaluate two simulations of the WRF model that differ in their parameterization of the Planetary Boundary Layer (PBL). For this goal, we have used data from 72 radiosondes launched in Fortaleza (CE) between April 5th to 25th of 2011 in the synoptic times. The PBL height was the evaluated metric and the observational data were calculated through the vertical potential temperature method, obtaining 245±28 m for nighttime and 925±63 m for daytime. The Asymmetric Convective Model V2 (ACM2) and the Mellor Yamada Nakanish and Niino 2.5 (MYNN2.5) PBL parameterizations have been evaluated. The skills of these parameterizations were evaluated by statistical comparison with observational data through Mean Absolute Error (MAE) and the refined Willmott’s index of agreement (dr). For ACM2, MAE was 282 m and 519 m and dr was 0.53 and 0.37 for the nighttime and daytime periods, respectively. In the MYNN2.5 simulation, MAE values were found between 312 and 266 m, with dr between 0.59 and 0.56 for the nighttime and daytime, respectively. At 06, 12 and 18 UTC, MYNN2.5 was better, considering both metrics. However, ACM2 presented better performance only at 00 UTC.