The Mediterranean response to different space-time resolution atmospheric forcings using perpetual mode sensitivity simulations
The Mediterranean response to different space-time resolution atmospheric forcings using perpetual mode sensitivity simulations
复制标题
使用永久模式灵敏度模拟地中海对不同时空分辨率大气强迫的响应
DOI：
10.1016/j.ocemod.2010.10.008
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发表时间：
2011
期刊：
影响因子：
3.2
通讯作者：
P. Drobinski
中科院分区：
文献类型：
--
作者：
C. L. Brossier;K. Béranger;C. Deltel;P. Drobinski
地中海盆地是一个半封闭的海，在不同的时间和空间尺度上，大气和海之间的相互作用和反馈在区域气候中起着主导作用。本研究通过用各种大气作用力以永久模式驱动NEMO-MED12海洋模式来分析地中海的响应，这些大气作用力都由WRF非静力中尺度大气模式产生，但在分辨率上不同：两种水平分辨率(盆地尺度20公里，西北地区6.7公里)和两种时间分辨率(日分辨率和三小时分辨率)。1998年8月至1999年7月可获得的大气场与根据卫星数据得出的估计值很好地吻合。地中海的热量收支代表着5W/m2的热量损失，年度淡水收支为−104m，与气候相一致。随着西北地区空间分辨率的提高，模式环流从−10%修改为+15%，−从30%修改为+50%，−从10%修改为+30%，EKE从−10%修改为+30%。随着陆地地形的改善，风速增大，特别是西北偏北地区的海洋对流过程增强。另一方面，由于海洋上层的日再层化，时间分辨率的增加减少了对流过程。它还降低了地面参数的高频变率，而由于对风的快速响应，它增加了地面的EKE值。
The Mediterranean basin features a semi-enclosed sea, where interactions and feedbacks between the atmosphere and the Sea at various temporal and spatial scales play a predominant role in the regional climate. This study analyzes the Mediterranean Sea response in sensitivity experiments conducted by driving the NEMO-MED12 oceanic model in perpetual mode with various atmospheric forcings, all produced by the WRF non-hydrostatic mesoscale atmospheric model, but differing by their resolutions: two horizontal resolutions (20km at basin scale and 6.7km in the North-Western [NWE] area) and two temporal resolutions (daily and three-hourly). The atmospheric fields available from August 1998 to July 1999 are in good agreement with estimates derived from satellite data. The heat budget of the Mediterranean Sea represents an heat loss of 5W/m2and the annual freshwater budget is −1.04m, in agreement with climatologies. An increase in the spatial resolution in the NWE area modifies the modeled circulation from −10% to +15% for the SST, from −30% to +50% for the SSS, from −10% to +30% for the MLD and from −10% to +30% for the EKE in surface. The increase in the wind speed with a better chanelling by the land orography enhances in particular the oceanic convection process in the NWE area. On the other hand, the increase in the temporal resolution reduces the convection process, because of the diurnal restratification of the oceanic upper layer. It also reduces the surface parameters high-frequency variability, whereas it increases the EKE values in surface, due to the rapid response to the wind.