Impacts of the Lower Stratosphere on the Development of Intense Tropical Cyclones
Impacts of the Lower Stratosphere on the Development of Intense Tropical Cyclones
复制标题
平流层低层对强热带气旋发展的影响
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
C. Kieu
中科院分区：
文献类型：
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作者：
Zach Moon;C. Kieu
本研究探讨平流层下层对强热带气旋发展及内核结构的潜在影响。通过对西北太平洋和北大西洋流域不同月平均探空廓线的飓风天气研究和预报（HWRF）模式初始化，发现平流层低层（LSL）通过在对流层顶附近形成一个额外的暖核，并伴随着沿着LSL的一个薄层入流，对热带气旋的结构和发展产生明显的影响。具体而言，对流层顶越低，TC强度越高，双暖芯结构越明显。同样，较弱的LSL层结也对应着较温暖的上层核心和较高的强度。更重要的是，在相同的海面温度下，双暖芯的形成对西北太平洋海盆的对流层顶变化比北大西洋海盆的对流层顶变化更敏感。结果表明，对流层顶和LSL层结的变化可能是一个重要的因素，是负责长期变化的TC强度。
This study examines potential impacts of the lower stratosphere on the development and the inner-core structure of intense tropical cyclones (TCs). By initializing the Hurricane Weather Research and Forecasting (HWRF) model with different monthly averaged sounding profiles in the Northwestern Pacific and the North Atlantic basins, it is shown that the lower stratosphere layer (LSL) can impose a noticeable influence on the TC structure and development via formation of an extra warm core near the tropopause along with a thin layer of inflow in the LSL at the high-intensity limit. Specifically, a lower tropopause level allows for higher TC intensity and a more distinct double warm core structure. Likewise, a weaker LSL stratification also corresponds to a warmer upper-level core and higher intensity. Of further significance is that the double warm core formation is more sensitive to tropopause variations in the Northwestern Pacific basin than those in the North Atlantic basin, given the same sea surface temperature. The results suggest that variations in tropopause level and LSL stratification could be an important factor that is responsible for the long-term variability of TC intensity.