Characeristics of Island-scale Airflow and Climate over the Hawaiian Islands

夏威夷群岛呈现出各种地形高度和结构，嵌入在天气和年际调制的信风体系中，构成了亚热带高纬度地形流和降水过程高分辨率研究的天然实验室。利用MM5/LSM（配对的Penn State/NCAR中尺度/陆地表面模式）和WRF（天气研究与预报模式）对近10年存档的高分辨率（1.5公里和3.0公里岛屿尺度）数值预报进行仔细的再分析，并选择重新运行，将用于探索各种问题，包括但不限于：(1)为什么考艾岛上的Wai'ale'ale山（1598米MSL）是地球上最潮湿的地方之一？(2)科纳夏季最大背风面降水的物理过程是什么？(3)是什么动力控制了夏威夷和毛伊岛分隔区强航道风的日变化和季节变化？(4)瓦胡岛等相对较低屏障后的逆流如何取决于信风特性？(5)厄尔尼诺诱发的调制如何影响夏威夷群岛信风逆温上下区域的小气候？(6)该地区形成困山背风波的具体条件是什么？本研究的智力价值在于将基于模型的表示和相关的夏威夷群岛岛屿-大气相互作用的动力学理解扩展到比以往更精细的尺度，并且在厄尔尼诺/南方涛动诱发的影响既大又不完全表征的区域内。更广泛的影响将包括研究生培训，但将扩大到提高对影响商业和运输、脆弱的海洋和陆地生态系统以及可再生能源发电能力的条件的理解。

The Hawaiian Islands, which present a variety of terrain heights and configurations embedded within a synoptically- and interannually-modulated trade wind regime, constitute a natural laboratory for high-resolution studies of orographic flow and precipitation processes at subtropical latitudes. A combination of careful reanalysis of nearly 10 years of archived high-resolution (1.5- and 3.0-km island-scale) numerical forecasts generated using the MM5/LSM (the paired Penn State/NCAR mesoscale/land-surface model) and WRF (Weather Research & Forecasting model) and select re-runs will be used to explore a variety of questions including but not limited to: (1) Why is Mount Wai'ale'ale (1598 m MSL) on Kauai one of the wettest spots on earth?; (2) What physical processes are responsible for a lee-side summer rainfall maximum on Kona?; (3) what dynamics control diurnal and seasonal variations in strong channel winds in the zone separating Hawaii and Maui?; (4) How does reverse flow in the wake of relatively lower barriers such as Oahu depend on trade-wind properties?; (5) How do El Nino-induced modulations affect the micro-climates of zones both above and below the trade-wind inversion across the Hawaiian archipelago?; and (6) What specific conditions favor development of trapped mountain lee waves in this region?The intellectual merit of this research rests on extension of model-based representations and associated dynamical understanding of island-atmosphere interactions across the Hawaiian archipelago to finer scales than has heretofore been possible, and within a zone where El Nino/Southern Oscillation-induced impacts are both sizable yet incompletely characterized. Broader impacts will include graduate student training but extend to improved understanding of conditions impacting commerce and transportation, fragile marine and terrestrial ecosystems, and capacity for renewable energy generation.