Structural Changes in the Tropical Hadley Circulation: Past and Future Trends

热带Hadley环流的纬向翻转是许多热带-外热带相互作用的基础，其年际变率和长期变化趋势对全球气候变率有着深刻的影响。文献表明，在过去的几十年里，Hadley环流的强度和位置发生了重大变化。目前尚不清楚是什么因素导致了这些变化，以及由此产生的反馈对热带和其他地区气候变化的影响。将要讨论的问题是：（1）导致Hadley环流变化和趋势的因素;（2）这些变化背后的机制及其与全球气候的联系。将使用包括当地无线电探空仪观测、再分析和遥感数据在内的广泛数据。智力优势：PI将执行（1）控制热带Hadley环流结构时空变化的物理过程分析和（2）诊断这些变化与全球天气和气候的关系。该研究将确定导致Hadley细胞强度和位置变化的因素。发展的指标，是基于确定的因素将有助于我们预测未来的气候变化与哈德利细胞的变化。

The meridional overturning of the tropical Hadley cell sets the stage for many tropical-extratropical interactions, and its interannual variability and long-term trends have profound impacts on the variability of global climate. Literature indicates that during the past several decades the strength and position of the Hadley cell have undergone significant changes. It is not known what factors caused these changes and effects of the resultant feedbacks on climate change over the tropics and other regions. The issues that will be addressed are (1) the factor(s) that cause the variability and trends of the Hadley cell and (2) the mechanisms behind those variations and their linkages to global climate. A wide range of data that includes local radiosonde observations, reanalysis, and remote sensing data will be used.Intellectual merit: The PI will perform (1) the analysis of the physical processes that control the spatial and temporal variations in the structure of the tropical Hadley cell and (2) diagnose how those variations are related to global weather and climate.Broader Impacts: The research will identify factors responsible for changes in the strengths and positions of Hadley cell. Development of indicators that are based on identified factors will help us to predict future climate changes associated with the changes in the Hadley cell.