The present study introduces a new boundary layer parameterization for weather and forecasting models. It is implemented here as a boundary layer module in Weather Research and Forecasting (WRF) model. The main novelty in the new scheme is that it includes prognostic equations for the heat flux and temperature variance, being the first WRF boundary layer scheme with that feature. This is specially aimed at improving the representation of nocturnal stable boundary layer and of its turbulence regimes, weakly and very stable. The effort is supported by previous studies that found that the two regimes and the transitions between them are better represented by simplified numerical schemes that represent the interactions between the surface and the air adjacent to it when the heat flux and temperature variance are solved prognostically. The results show that the two regimes are adequately simulated by the new scheme. Such an evaluation is presented in terms of the relationship between the turbulence velocity scale and mean wind speed, of the dependence of the potential temperature gradient near the surface and the mean wind speed, and by the relationship between flux and gradient Richardson numbers. In the new scheme, the relationship between thermal structure and the mean and turbulent flows arises naturally from the heat flux prognostic equation, not being arbitrarily imposed by an empirical stability function.

本研究为天气和预报模型引入了一种新的边界层参数化。它在此处作为天气研究和预报 (WRF) 模型中的边界层模块实施。新方案的主要新颖之处在于它包括热通量和温度变化的预测方程，是第一个具有该特征的 WRF 边界层方案。这特别旨在改善夜间稳定边界层及其湍流状态的表现，弱和非常稳定。这项努力得到了先前研究的支持，这些研究发现，当热通量和温度变化被预测求解时，这两种状态和它们之间的转变可以用简化的数值方案更好地表示，这些方案表示表面和与其相邻的空气之间的相互作用。结果表明，新方案充分模拟了这两种制度。这种评估是根据湍流速度尺度与平均风速之间的关系、地表附近的潜在温度梯度与平均风速的相关性以及通量与梯度理查森数之间的关系来进行的。在新方案中，热结构与平均流动和湍流之间的关系自然地从热通量预测方程中产生，而不是由经验稳定性函数任意强加。表面附近的潜在温度梯度与平均风速的依赖关系，以及通量和梯度理查森数之间的关系。在新方案中，热结构与平均流动和湍流之间的关系自然地从热通量预测方程中产生，而不是由经验稳定性函数任意强加。表面附近的潜在温度梯度与平均风速的依赖关系，以及通量和梯度理查森数之间的关系。在新方案中，热结构与平均流动和湍流之间的关系自然地从热通量预测方程中产生，而不是由经验稳定性函数任意强加。