The impact of tropical - extratropical interactions on downstream predictability (TROP)

在这个项目中，我们研究了有组织的热带对流系统，特别是正在经历温带转换(ET)的热带气旋与中纬度高层波导相互作用的机制。我们考虑了这种相互作用如何影响ET系统本身、中纬度气流和可能在下游发展的副热带气旋的动力学和可预测性。我们将使用观测、COSMO建模和数据拒绝相结合的方法来处理THORPEX太平洋亚洲区域战役的ET案例。诊断技术，包括PV逆温和面向对象的诊断将被应用于研究对流和天气尺度流动之间的相互作用。我们将通过对热带对流年和TIGGE资料的分析，利用集合预报系统(EPS)进行试验，并使用集合敏感性分析等技术对结果进行诊断，来研究不同热带对流模式对中纬度可预报性的影响。最后，我们将利用多尺度集合研究ET和副热带气旋发生期间结构变化的可预报性。这项研究的结果将被用来为未来的THORPEX野战定义观测战略。

In this project we investigate the mechanisms by which organised tropical convective systems, and, in particular, tropical cyclones undergoing extratropical transition (ET), interact with the midlatitude upper-level wave guide. We consider how this interaction influences the dynamics and predictability of the ET system itself, the midlatitude flow, and sub tropical cyclones that may develop downstream. We will use a combined observational, COSMO modelling, and data denial approach applied to the ET cases of the THORPEX Pacific Asian Regional Campaign. Diagnostic techniques, including PV inversion and object-oriented diagnostics will be applied to investigate the interactions between the convective and synoptic-scale flow. We will investigate the impact of different regimes of tropical convection on midlatitude predictability through analysis of Year of Tropical Convection datasets and TIGGE data, conducting experiments with ensemble prediction systems (EPS), and diagnosing the results with ensemble sensitivity analysis and other techniques. Finally, we will investigate the predictability of the structural changes during ET and of sub-tropical cyclogenesis using the multiscale ensemble. The results of this study will be used to define observational strategies for a future THORPEX field campaign.