当前位置:
X-MOL 学术
›
Boundary-Layer Meteorol.
›
论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
A Micrometeorological Analysis of the Vento Norte Phenomenon in Southern Brazil
Boundary-Layer Meteorology ( IF 4.3 ) Pub Date : 2020-07-14 , DOI: 10.1007/s10546-020-00540-x Michel Stefanello , Ernani de Lima Nascimento , Cinara Ewerling da Rosa , Gervasio Degrazia , Luca Mortarini , Daniela Cava
Boundary-Layer Meteorology ( IF 4.3 ) Pub Date : 2020-07-14 , DOI: 10.1007/s10546-020-00540-x Michel Stefanello , Ernani de Lima Nascimento , Cinara Ewerling da Rosa , Gervasio Degrazia , Luca Mortarini , Daniela Cava
A sonic anemometer is employed to investigate turbulent statistical characteristics and meteorological properties associated with a local windstorm known as the Vento Norte (Portuguese for north wind), which is observed in central Rio Grande do Sul state situated in southern Brazil. The Vento Norte consists of persistent and warm northerly gusts of moderate to strong magnitude that occur just downstream from a modest zonally-oriented downslope. This flow, which generates a shear-dominated atmospheric boundary layer, is investigated through analysis of turbulent properties of the velocity components and temperature measured over two years from a meteorological tower. The overall micrometeorological analysis highlights the influence of the Vento Norte phenomenon on the daily cycle of turbulent energy and fluxes and on the surface energy budget. A more detailed investigation of Vento Norte characteristics is performed by analyzing an extended Vento Norte event that lasted for approximately 35 h. In this episode, a strong increase in turbulence activity is observed on the vertical velocity component and in the absolute turbulent heat flux, as well as a reduction in the relative humidity. Further, the cospectra of the heat-flux wavelet suggest that the Vento Norte flow perturbs the boundary-layer turbulence in both daytime and night-time conditions. The surface energy budget shows a positive night-time soil heat flux and an enhanced positive latent heat flux, induced by the low relative humidity and intense turbulent activity during the Vento Norte event. The onset and demise of the Vento Norte event are characterized by sub-mesoscale activity in the velocity components and temperature field.
中文翻译:
巴西南部 Vento Norte 现象的微气象分析
使用声波风速计来研究与当地风暴相关的湍流统计特征和气象特性,称为 Vento Norte(葡萄牙语为北风),该风暴在位于巴西南部的南里奥格兰德州中部观察到。Vento Norte 由持续且温暖的偏北阵风组成,这些阵风发生在适度的带状下坡下游。这种流动产生了一个以剪切为主的大气边界层,通过分析两年来从气象塔测量的速度分量和温度的湍流特性进行了研究。整体微气象分析强调了北文托现象对湍流能量和通量的日常循环以及表面能量收支的影响。通过分析持续约 35 小时的扩展 Vento Norte 事件,对 Vento Norte 特征进行了更详细的调查。在这一集中,在垂直速度分量和绝对湍流热通量中观察到湍流活动的强烈增加,以及相对湿度的降低。此外,热通量子波的余谱表明,Vento Norte 流在白天和夜间条件下都会扰乱边界层湍流。表面能收支显示出正的夜间土壤热通量和增强的正潜热通量,这是由北文托事件期间的低相对湿度和强烈湍流活动引起的。
更新日期:2020-07-14
中文翻译:
巴西南部 Vento Norte 现象的微气象分析
使用声波风速计来研究与当地风暴相关的湍流统计特征和气象特性,称为 Vento Norte(葡萄牙语为北风),该风暴在位于巴西南部的南里奥格兰德州中部观察到。Vento Norte 由持续且温暖的偏北阵风组成,这些阵风发生在适度的带状下坡下游。这种流动产生了一个以剪切为主的大气边界层,通过分析两年来从气象塔测量的速度分量和温度的湍流特性进行了研究。整体微气象分析强调了北文托现象对湍流能量和通量的日常循环以及表面能量收支的影响。通过分析持续约 35 小时的扩展 Vento Norte 事件,对 Vento Norte 特征进行了更详细的调查。在这一集中,在垂直速度分量和绝对湍流热通量中观察到湍流活动的强烈增加,以及相对湿度的降低。此外,热通量子波的余谱表明,Vento Norte 流在白天和夜间条件下都会扰乱边界层湍流。表面能收支显示出正的夜间土壤热通量和增强的正潜热通量,这是由北文托事件期间的低相对湿度和强烈湍流活动引起的。