In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility a...In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility along the Shandong Peninsula coast to 100 m or much less at some sites. Satellite images, surface observations and soundings at islands and coasts, and analyses from the Japan Meteorology Agency （JMA） axe used to describe and analyze this event. The analysis indicates that this sea fog can be categorized as advection cooling fog. The main features of this sea fog including fog area and its movement axe reasonably reproduced by the Fifth-generation Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model （MM5）. Model results suggest that the formation and evolution of this event can be outlined as： （1） southerly warm/moist advection of low-level air resulted in a strong sea-surface-based inversion with a thickness of about 600 m; （2） when the inversion moved from the warmer East Sea to the colder Yellow Sea, a thermal internal boundary layer （TIBL） gradually formed at the base of the inversion while the sea fog grew in response to cooling and moistening by turbulence mixing; （3） the sea fog developed as the TIBL moved northward and （4） strong northerly cold and dry wind destroyed the TIBL and dissipated the sea fog. The principal findings of this study axe that sea fog forms in response to relatively persistent southerly waxm/moist wind and a cold sea surface, and that turbulence mixing by wind shear is the primary mechanism for the cooling and moistening the marine layer. In addition, the study of sensitivity experiments indicates that deterministic numerical modeling offers a promising approach to the prediction of sea fog over the Yellow Sea but it may be more efficient to consider ensemble numerical modeling because of the extreme sensitivity to model input.展开更多
薇甘菊(Mikania micrantha H B K.)是一种危害极大的外来入侵农林杂草。为了预测薇甘菊在中国的适生区,该文运用预设预测规则的遗传算法(genetic algorithm for rule-set production,GARP)和最大熵(Maximum Entropy,MaxEnt)模型对薇甘...薇甘菊(Mikania micrantha H B K.)是一种危害极大的外来入侵农林杂草。为了预测薇甘菊在中国的适生区,该文运用预设预测规则的遗传算法(genetic algorithm for rule-set production,GARP)和最大熵(Maximum Entropy,MaxEnt)模型对薇甘菊在中国的适生区进行预测,并运用受试者工作曲线(receiver operating characteristic,ROC)分析方法对2种模型的预测结果进行分析,选出最优模型进行预测,同时对环境变量进行刀切法分析,判断环境变量对薇甘菊分布的影响。结果表明,GARP和MaxEnt模型ROC曲线下面的面积AUC(area under the ROC curve)均值分别为0.910和0.971,MaxEnt模型的AUC值更大,预测结果更准确,运行速度更快,更适合用于薇甘菊的适生区预测;对环境变量进行刀切法表明,海拔和季节性降水量方差对薇甘菊的分布影响最小,年温变化范围、年降水量、最湿月份降水量、最湿季度降水量、温度变化方差这5个环境变量对薇甘菊适生区预测影响最大;预测结果显示薇甘菊在中国大陆的适生区主要集中在海南、广东、广西、香港、澳门、云南、福建、西藏、贵州等省,其中西藏东南部和西南部、贵州西南部、福建中南部等地区应该加强监测及预警。展开更多
文摘In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility along the Shandong Peninsula coast to 100 m or much less at some sites. Satellite images, surface observations and soundings at islands and coasts, and analyses from the Japan Meteorology Agency （JMA） axe used to describe and analyze this event. The analysis indicates that this sea fog can be categorized as advection cooling fog. The main features of this sea fog including fog area and its movement axe reasonably reproduced by the Fifth-generation Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model （MM5）. Model results suggest that the formation and evolution of this event can be outlined as： （1） southerly warm/moist advection of low-level air resulted in a strong sea-surface-based inversion with a thickness of about 600 m; （2） when the inversion moved from the warmer East Sea to the colder Yellow Sea, a thermal internal boundary layer （TIBL） gradually formed at the base of the inversion while the sea fog grew in response to cooling and moistening by turbulence mixing; （3） the sea fog developed as the TIBL moved northward and （4） strong northerly cold and dry wind destroyed the TIBL and dissipated the sea fog. The principal findings of this study axe that sea fog forms in response to relatively persistent southerly waxm/moist wind and a cold sea surface, and that turbulence mixing by wind shear is the primary mechanism for the cooling and moistening the marine layer. In addition, the study of sensitivity experiments indicates that deterministic numerical modeling offers a promising approach to the prediction of sea fog over the Yellow Sea but it may be more efficient to consider ensemble numerical modeling because of the extreme sensitivity to model input.
文摘薇甘菊(Mikania micrantha H B K.)是一种危害极大的外来入侵农林杂草。为了预测薇甘菊在中国的适生区,该文运用预设预测规则的遗传算法(genetic algorithm for rule-set production,GARP)和最大熵(Maximum Entropy,MaxEnt)模型对薇甘菊在中国的适生区进行预测,并运用受试者工作曲线(receiver operating characteristic,ROC)分析方法对2种模型的预测结果进行分析,选出最优模型进行预测,同时对环境变量进行刀切法分析,判断环境变量对薇甘菊分布的影响。结果表明,GARP和MaxEnt模型ROC曲线下面的面积AUC(area under the ROC curve)均值分别为0.910和0.971,MaxEnt模型的AUC值更大,预测结果更准确,运行速度更快,更适合用于薇甘菊的适生区预测;对环境变量进行刀切法表明,海拔和季节性降水量方差对薇甘菊的分布影响最小,年温变化范围、年降水量、最湿月份降水量、最湿季度降水量、温度变化方差这5个环境变量对薇甘菊适生区预测影响最大;预测结果显示薇甘菊在中国大陆的适生区主要集中在海南、广东、广西、香港、澳门、云南、福建、西藏、贵州等省,其中西藏东南部和西南部、贵州西南部、福建中南部等地区应该加强监测及预警。
