Long-term impacts of ocean wave-dependent roughness on global climate systems
Long-term impacts of ocean wave-dependent roughness on global climate systems
复制标题
海浪相关的粗糙度对全球气候系统的长期影响
DOI：
10.1002/2016jc012621
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
T. Takemi and R. Mizuta
中科院分区：
文献类型：
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作者：
T. Shimura;N. Mori;T. Takemi and R. Mizuta
海洋表面波在气候系统中发挥着积极的作用，但在全球气候模式（GCMs）中往往被忽略。在大气GCM（MRI-AGCM）中使用光谱波模型WAVEWATCH III实现了与波相关的表面粗糙度。考虑了两种类型的波浪相关粗糙度，即波陡和波龄。将具有波浪相关粗糙度的气候模拟与仅具有风速相关粗糙度的模拟进行了比较。在具有波陡相关粗糙度的气候模拟中，粗糙度的空间分布与涌浪优势的空间分布相关。在波浪年龄相关粗糙度的模拟中，粗糙度的空间分布与风向平稳性的空间分布相关。两个模拟都显示热带地区的粗糙度降低，这导致表面风速增加高达15%;与仅具有风速依赖粗糙度的基线模拟相比，这些增强的风速更接近观测结果。我们发现，在热带地区的粗糙度和风速的增强，导致大气环流的显着变化，在Hadley环流和降水。Hadley环流和降水对海面粗糙度变化的特征响应。
Ocean surface waves can play an active role in climate systems, but they are often ignored in Global Climate Models (GCMs). Wave‐dependent surface roughness was implemented within the Atmospheric GCM (MRI‐AGCM) using the spectral wave model WAVEWATCH III. Two types of wave‐dependent roughness, due to wave steepness and to wave age, were considered. Climate simulations with wave‐dependent roughness were compared to simulations with just wind speed‐dependent roughness. In climate simulation with wave steepness‐dependent roughness, the spatial distribution of roughness is correlated to that of swell dominance. In simulation with wave age‐dependent roughness, the spatial distribution of roughness is correlated to that of wind direction stationarity. Both simulations show reduced roughness in the tropics, which leads to an enhancement of surface wind speeds by up to 15%; these enhanced wind speeds are closer to observations compared with the baseline simulation with just wind speed‐dependent roughness. We find that the reduced roughness and the enhanced wind speeds in the tropics lead to significant changes in atmospheric circulation, as in Hadley circulation and precipitation. The characteristic responses of the Hadley circulation and precipitation to changing sea surface roughness are presented.