在AERMOD的城市选项中重新审视对流的边界层假设
Jonathan Retter1,2, Robert Christopher Owen2, Annamarie Leske3
1Oak Ridge Institute for Science and Education Research, Research Triangle Park, NC 27711, USA.
概括
这项研究修改了AERMOD模型的城市热岛 (UHI) 计算,发现其夜间感知热量流量估计经常被高估. 使用GOES-16卫星数据用于陆地表面温度 (LST) 提供了更准确的UHI校正,改善了夜间热流估计.
科学领域:
- 大气科学 大气科学
- 环境科学 环境科学
- 遥感 遥感 遥感 遥感
背景情况:
- 城市地区形成了独特的热岛 (UHI),影响温度和感知热量流.
- AERMOD模型的城市分散选项使用人口数据,经常高估夜间感知热量流.
研究的目的:
- 通过将基于人口的温度差异替换为卫星衍生的陆地表面温度 (LST) 数据,重新评估AERMOD的城市选择.
- 通过使用远程传感UHI数据,为感知热量流量开发城市特定的导向校正.
主要方法:
- 使用GOES-16卫星数据为480个美国城市地区生成一个每月平均,每小时,依赖风向的LST UHI数据库.
- 我们比较了AERMOD的基于人口的
Δ T 与GOES-16 LST衍生的Δ T 四个城市. - 应用GOES-16衍生
Δ T 作为对AERMOD的合理热量流估计的调整.
主要成果:
- AERMOD预测的夜间值明显高 (416%1048%) 于GOES-16观测值.
- 在AERMOD中高估的ΔT导致了不现实的夜间感知热量流 (>100W/m2).
- 基于GOES-16的校正产生了现实的中性到略微积极的夜间感知热量流值.
结论:
- AERMOD的城市选项高估了夜间温度差异和可感知的热量流.
- GOES-16 LST数据提供了更准确的方法来纠正城市感知热量流.
- 原来的AERMOD评估可能将UHI效应与低水平喷气现象混为一谈.
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