How Do Energy Fluxes Link Precipitation Variability across the Tropical Weather-Climate Continuum?

Near the equator, a nearly permanent band of high rainfall circles the globe. It moves north and south with the seasons, and in the summer over land it becomes Earth’s monsoons in places like India, providing rainfall that billions of people rely on. Its movements are closely related to north and south transports of energy by the atmosphere. Because of traveling disturbances along the rainband, however, the relationship between the rainband location and the north-south energy transports is complicated. The prevailing theory thereof and many climate models fail to capture this relationship. The investigators will use the observed temperature, wind, precipitation, and moisture to establish, for the first time, the precise contribution to north-south energy transports by the different types of tropical disturbances. Combining this information with climate model simulations, the investigators will develop new theories for the energy transports by individual disturbance types and incorporate these into existing theory. Finally, in collaboration with the City College of New York (CCNY), the investigators will build three state-of-the-art rotating tank platforms for teaching concepts in climate science, weather, and oceanography and use the devices to contribute to CCNY science outreach events. This work will improve our fundamental understanding of traveling tropical disturbances (such as the Madden-Julian Oscillation) which are known to influence the likelihood of extreme weather events. It will unify work across seemingly disparate time and spatial scales spanning the weather-climate continuum from small, short-lived waves to the semi-permanent, circum-global rainband. It will pinpoint likely sources of error in tropical rainfall and ways to address them in weather and climate models, helping to reduce uncertainties in projections of future changes in monsoon regions home to billions of vulnerable people. The collaboration with CCNY will bring core earth science concepts to underserved K-12 students, potentially stimulating interests in STEM and encouraging them to pursue college. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.