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.
