Intensifying Monsoon Brings Relief and Flood Risk Across East Asia and Australia

Strategic Insights -

A team of researchers from James Cook University and Flinders University has analyzed 150,000 years of climate records to understand the impact of climate change on the monsoon season in East Asia and Australia. According to the study, the monsoon is likely to intensify, bringing both relief to drought-stricken lands and an increased risk of flooding in East Asia. The research, published in Quaternary Science Reviews, reveals a continuous record of monsoon rainfall patterns dating back beyond the last interglacial period, providing valuable insights into the interrelation between the monsoon systems in East Asia and Australia.

Key Takeaways:

  • The research team, led by Professor Michael Bird, analyzed sediments at Girraween Lagoon near Darwin, revealing a 150,000-year record of monsoon rainfall patterns.
  • The study shows that the monsoon is likely to intensify, resulting in a higher risk of flooding in East Asia and worsening the impact of droughts in the region.
  • The researchers found that the intensity of the monsoon is closely tied to sea level changes, which shift the location of the northern coastline by up to 320 km.
  • The study uncovered "bursts" of intense monsoon activity, some lasting less than 10,000 years, which align with Heinrich events - abrupt pulses of freshwater into the North Atlantic from rapidly melting ice.
  • The weakening of the Gulf Stream, already underway due to climate change, could lead to increased rainfall in northern Australia and droughts in parts of East Asia.
  • The data suggest that the weather trends witnessed today, such as the drying in China and wetting in northern Australia, could accelerate if the Gulf Stream continues to weaken.

Statistics:

  • The research analyzed a 150,000-year record of monsoon rainfall patterns.
  • The study revealed a 320 km shift of the northern coastline due to sea level changes.
  • The bursts of intense monsoon activity lasted less than 10,000 years.
  • The weakening of the Gulf Stream could lead to increased rainfall in northern Australia, resulting in droughts in parts of East Asia.
  • The region extending from China through Southeast Asia, the maritime continent, and western Indo-Pacific warm pool on the Equator, to Australia, is home to almost a billion people and five terrestrial Biodiversity Hotspots.

Sources:

  • Quaternary Science Reviews
  • Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage (CE170100015)
  • Centre of Excellence for Indigenous and Environmental Histories and Futures (CE230100009)
  • Australian Research Council Laureate Fellowship (FL140100044)