39th Conference on Climate Variability and Climate Change
Title: Energetic Constraints on the South Asian Summer Monsoon Interannual Variability
38th Conference on Climate Variability and Climate Change
Title: Energetic Constraints on Seasonal Zonal Shifts of the Indo-Pacific Intense Precipitation Regions
Prediction of Monsoon Extremes
Title: Mechanisms governing the Rainfall over India during Monsoon Onset and Post-Onset Phases
12th Symposium of Madden Julian Oscillation and Sub-Seasonal Monsoon Variability
Title: Mechanisms behind Sub-Seasonal Rainfall Variabilities of Indian Monsoon
Understanding the Monsoons using the Energy Flux Framework:
The Inter-Tropical Convergence Zone (ITCZ) is the region of enhanced precipitation. It coincides with the rising branch of the Hadley circulation. Hadley circulation transports
energy meridionally from the equator to the poles. Hence, recent studies have explained the ITCZ using an energetic perspective. ITCZ shows a northward propagation as
the season evolves from boreal winter to boreal summer. Studies have shown that when the ITCZ shifts over the Indian Ocean and adjoining landmass, the monsoons get
established. Using an energy flux framework, it is found that the meridional energy divergence zone called the Energy flux equator (EFE) first jumps over the Indian region during
May, and hence the precipitation maxima shift in June, establishing monsoons.
Two Stable Regions of Convection
During both Boreal summer and winter, it is observed that Sea Surface Temperatures (SST) and total column-integrated water vapor over the Maritime Continent are the largest. However, the source region of the energy never stays over there. The source region of energy is identified as the region from where energy fluxes of weaker magnitude diverge in all directions. These regions co-occur with the strong ascending mid-level vertical velocity which is a proxy for intense convection. These regions are found either over the West-Central Pacific during the Boreal Winter or East Asia during the Boreal Summer. This study tries to find a mechanism for the formation of two stable east-west locations of the Energy Source Zones using an energy flux potential-based approach. Analyses show that increased amplitudes of meridional averaged turbulent heat flux potential over East Asian and the West-Central Pacific regions during Boreal Summer and Boreal Winter, respectively, play a dominant role in establishing an energy source zone. However, the role of radiative heat flux potential over the East Asian region during the Boreal summer can't be ignored for the establishment of energy source.