Dusty weather forecasts using the MesoNH mesoscale atmospheric model
Dusty weather forecasts using the MesoNH mesoscale atmospheric model
复制标题
使用 MesoNH 中尺度大气模型进行沙尘天气预报
DOI：
10.1029/2005jd007007
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发表时间：
2006
影响因子：
--
通讯作者：
L. Gomes
中科院分区：
文献类型：
--
作者：
A. Grini;P. Tulet;L. Gomes
[1]一些研究表明气溶胶在地球辐射平衡中的重要性。沙尘的辐射效应早已在全球和区域气候模型中得到量化。在数值天气预报（NWP）模式中包括在线气溶胶预测的研究较少。预测气溶胶的气候效应不同于将气溶胶主动纳入天气预测，因为气候模式给出的是长时间尺度上的平均响应，而天气预测模式的目的是在短时间尺度上计算正确的天气。在本文中，我们运行了一个中尺度数值预报方案，对沙尘气溶胶有四种不同的假设：（1）没有沙尘，（2）沙尘气溶胶的气候学数据集，（3）使用沙尘卷吸和沉积模式（DEAD）预测沙尘，（4）与假设3相同，但减少了单次散射。结果表明，沙尘的假设对模式中地面温度和对流降水的预报是很重要的。沙尘通过改变辐射通量改变模式物理。我们解释的变化，通过分析四个区域接近主要粉尘源的能量预算。这些区域包括对流区和非对流区。在海洋上空的对流区，沙尘可以减少对流活动。气溶胶的垂直梯度及其单次散射反射率决定了它们的效率。在陆地上，沙尘也影响地表能量收支，因此，如果沙尘羽流经过水从地表蒸发的地区，就会导致潜热通量减少。
[1] Several studies have shown the importance of aerosols in the Earth's radiative balance. The radiative effect of dust has earlier been quantified in global and regional climate models. Fewer studies have included prediction of aerosols online in numerical weather prediction (NWP) models. Predicting climate effect of aerosols is different from including aerosols actively in weather prediction because climate models give average responses over long timescales, whereas the purpose of weather prediction models is to calculate the right weather on short timescales. In this paper, we run a mesoscale NWP with four different assumptions on dust aerosols: (1) no dust, (2) climatological data set for dust aerosols, (3) forecasted dust using the Dust Entrainment and Deposition model (DEAD) and (4) same as assumption 3 but with decreased single scattering albedo. We show that the assumption on dust is important for predicting ground temperature and convective precipitation in the model. Dust changes the model physics through changing the radiative fluxes. We interpret the changes through analyzing the energy budgets for four zones close to the major dust sources. The zones include both convective and nonconvective areas. In convective areas over ocean, dust can decrease convective activity. The vertical gradient of the aerosols and their single scattering albedo determine how efficient they are. Over land, dust also influences the surface energy budget so that decreased latent heat fluxes result if dust plumes pass over areas where water evaporates from the surface.