Synchronization of extreme rainfall during the Australian summer monsoon: Complex network perspectives

Area of Science:

• Climate Science
• Network Theory
• Meteorology

Background:

• Monsoon rains are crucial for agriculture but extreme events cause floods.
• Understanding Australian summer monsoon (ASM) development is vital for water resource management and disaster preparedness.

Purpose of the Study:

• To apply nonlinear causation measures and complex network analysis to extreme rainfall data for studying ASM development.
• To reveal the multiscale characteristics of ASM and identify key indicators of its onset.

Main Methods:

• Utilized Tropical Rainfall Measuring Mission satellite data (1998-2015) for rain rate estimates.
• Constructed complex networks of extreme rainfall using event synchronization.
• Analyzed network centrality measures (degree, local clustering) and community structure.

Main Results:

• Network centrality measures revealed the multiscale nature of ASM development, highlighting land-sea surface heating contrasts.
• Clustering coefficient and community structure changes correlated with the climatological ASM onset in late December.
• A specific network community extending from the near-equatorial region provided insights into ASM development.

Conclusions:

• Complex network analysis provides a novel method to study monsoon dynamics, complementing traditional weather analysis.
• Network measures derived from rainfall data show significant potential for monsoon onset prediction.
• Findings offer a new perspective on monitoring monsoon development and its associated extreme weather events.