Giovanni Liguori - The Role of The Role of Meridional Modes in Pacific Climate Variability and Change Meridional Modes in Pacific Climate Variability and Change

Event type: 
21 March 2019
2.00 - 3.00pm

Climate Change Research Centre, Seminar Room, Mathews Building 4th floor, UNSW, Sydney

Dr. Giovanni Liguori
Centre of Excellence in Climate Extremes at Monash University, Melbourne, Australia
Climate Change Research Centre

Decadal changes in Pacific climate affect long-term transitions in marine ecosystems and influence the statistics of weather including ocean and atmosphere extremes such as strong droughts, hurricanes and marine heatwaves. However, the physical mechanisms that generate decadal variance and how these dynamics will change under anthropogenic forcing remains unknown. This research utilizes statistical and physical modeling to investigate the role of extratropical El Niño-Southern Oscillation (ENSO) precursors such as Pacific Meridional Modes (PMMs) in driving Pacific decadal variability and change. In the first part, , we develop an interpretative framework for the Pacific decadal variability (PDV) in which the stochastic variability of the North Pacific Oscillation energizes the decadal-scale sea surface temperature anomalies (SSTa) variability in the extratropics through PMM dynamics. In the second part, we use the interpretative framework to explore how the PDV has changed in the observational record, and how it is expected to change under anthropogenic forcing. In the third part, we investigate the relative importance of the NPMM and South PMM (SPMM) in ENSO and tropical Pacific decadal variability by performing “surgical” experiments in which the NPMM and SPMM are selectively suppressed.


Brief Biography: Giovanni Liguori received his PhD in Climate Dynamics and Oceanography with minor in Applied Mathematics from the Georgia Institute of Technology, USA, in 2018. His research activity is largely directed towards understanding the mechanisms that generate decadal-scale climate variability and climate change in the Pacific Ocean. During his PhD he diagnosed the role of extra-tropical El Niño precursor dynamics (e.g., Meridional Modes) in generating tropical decadal variability, and examined different mechanisms through which changes in mean state associated with anthropogenic forcing impact the dynamics of Meridional Modes. Giovanni has recently relocated in Australia where he is research fellow of the Centre of Excellence in Climate Extremes at the Monash University. He is expanding on his Ph.D. research to include the role of inter-basin interactions. Aside from his main research topic, he has great interest in climate extremes, ocean modeling, regional climate modeling.