Research

Earth, Atmosphere & Environment Sciences

Title :

Investigation of the MJO modulation of tropical synoptic scale variability and equatorial waves.

Area of research :

Earth, Atmosphere & Environment Sciences

Focus area :

seismic Hazard Analysis

Principal Investigator :

Dr. suhas Ettammal, Indian Institute of science Education And Research (IIsER), Pune, Maharashtra

Timeline Start Year :

2024

Timeline End Year :

2027

Contact info :

Details

Executive Summary :

The Madden-Julian oscillation (MJO) is a slow eastward propagating system of tropical disturbances that is the dominant source of predictability in the sub-seasonal to seasonal timescale. Its persistent diabatic heating and large scale circulation can be stationary compared to synoptic scale disturbances. However, a mechanistic framework for the scale interaction between the MJO and synoptic scale variability and its impact on tropical weather is still missing. The MJO exerts significant control on tropical weather by impacting the genesis, strength, and characteristics of equatorial wave modes. The major modes of tropical synoptic scale disturbances are the westward propagating Mixed Rossby-Gravity (MRG) waves and eastward propagating Kelvin waves. The MJO's asymmetric diabatic heating in the tropics may control the frequency of these wave events. The lowering of gross moist stability of the atmosphere by MJO may also contribute to an increase in convection-circulation coupling strength, enhancing the vertical propagability of the waves. Quantifying the relative contribution of MJO in modulating tropical disturbances could provide an estimate of the predictability of these systems.

Co-PI:

Dr. Neena Joseph Mani, Indian Institute of science Education And Research (IIsER), Pune, Maharashtra (411008)

Total Budget (INR):

24,59,080

Organizations involved