Understanding the feedback loop between the height of the planetary boundary layer (PBL) and the concentration of absorbing aerosols is crucial for developing more accurate forecasting models. For this purpose, we enhanced the existing PBL model developed by M. Witek et al. [1] in NASA Jet Propulsion Lab based on the so-called Eddy Diffusivity-Mass flux (EDMF) scheme [2]. Although the study focused on the new form of the entrainment coefficient in the EDMF model, they produced a robust and fast 1D numerical model written entirely in MATLAB.

To investigate the previously mentioned feedback loop in PBL with aerosols (Polluted PBL), the additional radiation transfer module was added to the EDMF scheme. We used the NASA Langley Fu-Liou [3] Radiation Transfer model (version from 2004) with added functionality enabling input custom vertical profiles of aerosol properties.

The model was supplied with synthetic and realistic profiles of the PBL and aerosol parameters. We varied the optical depth and single scattering albedos and recorded the model output. Initial results showed that the model calculations are qualitatively in line with expectations. We plan to further develop, refine and validate the model through comparison with experimental observations. We expect it could be a valuable tool for understanding the aerosol influence on the strongly unstable Polluted PBL.

During the seminar I will:
outline the basic principles of both models,
show how they were joined together,
present a couple of plots produced by the model.

[1] Witek, M. L., J. Teixeira, and G. Matheou, 2011: An integrated TKE-based eddy-diffusivity/mass-flux boundary layer closure
for the dry convective boundary layer. J. Atmos. Sci., 68, 1526–1540, https://doi.org/10.1175/2011JAS3548.1.

[2] Siebesma, A. P., Soares, P. M. M. and J. Teixeira, 2007: A combined eddy-diffusivity mass-flux approach for the convective boundary layer. J. Atmos. Sci., 64, 1230–1248, https://doi.org/10.1175/JAS3888.1

[3] GitHub - fredgrose/Ed4_LaRC_FuLiou: Edition 4 version of LaRC FuuLiou Broadband Correlated K Sw & Lw Radiative Transfer code