Evaporative Implications of Dry‐Air Outbreaks Over the Northern Red Sea
Evaporative Implications of Dry‐Air Outbreaks Over the Northern Red Sea
复制标题
北红海干燥空气爆发的蒸发影响
DOI：
--
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
A. Bower
中科院分区：
文献类型：
--
作者：
Viviane V. Menezes;J. Farrar;A. Bower
我们调查向西事件对红海蒸发的影响，使用35年的第二次现代回顾性分析研究和应用再分析，以及为期2年的现场观测记录，从一个装有大量仪器的海气相互作用系泊。这些事件在北方冬季很常见，其影响类似于中极和副极纬度地区发生的冷空气爆发。它们造成海洋的极端热损失，主要是潜热通量。与冷空气爆发不同，加强的热量损失是由于相对湿度低，正如我们通过潜热通量分解所显示的那样。在这些事件中，降雨量可以忽略不计，我们称之为干空气爆发。我们还研究了有利于它们发生的大气环流模式，这与阿拉伯半岛中北部的阿拉伯高压增强有关，这一特征似乎是西伯利亚高压的延伸。分析表明，北方红海上空的向西和波斯湾冬季的沙马风很可能是同一次天气尺度特征的一部分。第二次现代研究和应用回顾性分析表明，从1980年到2015年，红海北方的向西事件发生率有所增加，特别是大规模事件的频率，其原因有待调查。我们假设，干空气爆发可能会导致表面红海东部边界流的表面水团转化，并可能代表海洋温盐驱动的翻转环流的一个重要过程。
We investigate the impacts of westward wind events on the Red Sea evaporation using the 35‐year second Modern‐Era Retrospective analysis for Research and Applications reanalysis and a 2‐year‐long record of in situ observations from a heavily instrumented air‐sea interaction mooring. These events are common during boreal winter, and their effects are similar to cold‐air outbreaks that occur in midpolar and subpolar latitudes. They cause extreme heat loss from the sea, which is dominated by latent heat fluxes. Different from cold‐air outbreaks, the intensified heat loss is due to the low relative humidity as we show through latent heat flux decomposition. Rainfall is negligible during these events, and we refer to them as dry‐air outbreaks. We also investigate the general atmospheric circulation pattern that favors their occurrence, which is associated with an intensified Arabian High at the north‐central portion of the Arabian Peninsula—a feature that seems to be an extension of the Siberian High. The analyses reveal that the westward winds over the northern Red Sea and the winter Shamal winds in the Persian Gulf are very likely to be part of the same subsynoptic‐scale feature. The second Modern‐Era Retrospective analysis for Research and Applications reanalysis indicates that the occurrence of westward wind events over the northern Red Sea has grown from 1980 to 2015, especially the frequency of large‐scale events, the cause of which is to be investigated. We hypothesize that dry‐air outbreaks may induce surface water mass transformation in the surface Red Sea Eastern Boundary Current and could represent a significant process for the oceanic thermohaline‐driven overturning circulation.