Initiation and Intensification of Tropical Depressions over the Southern Indian Ocean: Influence of the MJO
Initiation and Intensification of Tropical Depressions over the Southern Indian Ocean: Influence of the MJO
复制标题
南印度洋热带低压的形成和增强：MJO 的影响
DOI：
--
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
J. Duvel
中科院分区：
文献类型：
--
作者：
J. Duvel
利用ERA-Interim全球大气再分析，发展了一种跟踪热带低压系统从早期热带低气压（TD）阶段到可能增强为发达热带气旋（TC）的方法。使用IBTrACS数据集识别不同的TC阶段。这种方法检测到更多的TD启动相比，单独的IBTrACS，从而提供了一个更全面的数据集来研究的气旋生成，分别考虑TD启动和强度的概率。在南印度洋（SIO），MJO调制的TC的数量主要是由于调制的TD启动的数量，其次是他们的强度的概率。TD在55° E、75° E和95°E的起始位置更有可能，这主要归因于低层纬向风的不稳定气旋性纬向切变的发展。这种剪切力的加强是由于（i）与降水有关的热低压，以及（ii）与降水有关的热低压。
AbstractUsing ERA-Interim global atmospheric reanalysis, an original tracking approach is developed to follow tropical low pressure systems from the early tropical depression (TD) stage up to possible intensification into developed tropical cyclones (TCs). The different TC stages are identified using the IBTrACS dataset. This approach detects many more TD initiations compared to IBTrACS alone and thus gives a more comprehensive dataset to study the cyclogenesis by considering separately TD initiations and the probability of intensification.In the south Indian Ocean (SIO), the MJO modulation of the number of TCs is primarily due to the modulation of the number of TD initiations and secondarily to the probability of their intensification. The TD initiations are more probable at 55°, 75°, and 95°E and can be primarily attributed to the development of an unstable cyclonic meridional shear of the zonal wind at low levels. The reinforcement of this shear results from (i) a heat low, related to a precipitation a...