About me
I am a Senior Lecturer in the School of Earth, Atmosphere & Environment at Monash University and an associate investigator with the ARC Centre of Excellence for Climate Extremes. My research interests are in atmospheric dynamics and climate change. I am particularly interested in the influence of cloud and precipitation processes on atmospheric circulations of a wide range of spatial scales.
August 2022
New paper on understanding changes in the tropical circulation under warming
A new paper led by Sramana Neogi uses a heirarchy of models to help understand changes in the structure of the tropuical circulation under warming (Neogi & Singh, 2022). The study uses a cloud-resolving model and a simple plume model to understand the changes in the vertical structure of a prototype tropical circulation as the surface temperature is increased. The results show that the circulation becomes increasingly top-heavy with warming, leading to a negative dynamical contribution to precipitation, despite an overall strengthening of the circulation in terms of its peak upward velocity. The plume model indicates that these results may be understood as a consequence of entrainment on the lower tropospheric lapse rate becoming increasingly important as the atmosphere warms.
July 2022
New magazine article in Physics Today
In collaboration with Prof. Morgan O'Neill, we have published a short article in Physics Today entitled Thermodynamics of the climate system. In the article we describe how the Earth acts a giant planetary-scale heat engine, and we discuss how thermodynamic concepts from physics may provide insight to the workings of our climate system. The article is a companion to our detailed review describing applications of the second law of thermodynamics in climate research in Reviews of Modern Physics
April 2022
New paper describing future changes in large-scale convective aggregation in climate projections
A new paper led by Philip Bläckberg shows that most climate models (17 of the 19 we investigated) project increases in large-scale aggregation of precipitation in response to global climate change (Bläckberg & Singh, 2022). Previous studies have suggested changes in aggregation as one mechanism by which future changes in preciptiation extremes may be amplified. However, we find little relationship between tropics-wide metrics of convective aggregation and precipitation extremes across models, although most models have significant interannual relationships between these quantities. These results suggest that processes other than aggregation may dominate the intermdodel spread in preciptiation extremes.
April 2022
New paper on the interaction between moist convection and large-scale ascent in the tropics
Our group has published a new paper where we develop a simple model for understanding how moist convective processes interact with large-scale ascending motion in the tropics (Singh & Neogi, 2022). Specifically, the model allows one to calculate the vertical structure of the ascending motion given some parameter relating to mixing and evaporation within convective clouds. This new theoretical framework will be useful for understanding how the tropical circulation changes under climate change. Look out for a forthcoming paper in which we explore this application led by Sramana Neogi!
Opportunities
I currently have positions open for PhD students and honours students to work on a range of projects broadly concerning the dynamics of the tropical atmosphere. Some potential projects are outlined here, but please contact me if you are interested in working in my group.