Australian bush fire

Subject: Environment

Context:

Nearly three billion animals were killed or displaced during Australia’s devastating bushfires of the past year.

Concept:

• Bushfires are a routine occurrence in the country, but this bushfire season is believed to be the worst and has started even before the beginning of the Southern Hemisphere summer.
• Australia, where the summer starts around October, is known to be the most fire-prone of all continents.
• This is mainly because Australia is also the driest inhabited continent.Almost 70% of its area comprises arid or semi-arid land, with average annual rainfall less than 350 mm.

Reasons

• Prolonged Drought: The three years between 2017 and 2019 were the driest 36-month period ever in the New South Wales (a state of Australia).
• 2019 happened to be the warmest and driest year for the country since 1900.
• Positive Indian Ocean Dipole (IOD): In 2019, the problem has been compounded by the presence of one of the strongest-ever positive Indian Ocean Dipole (IOD) events. Positive IOD events are often associated with a more severe fire season for South-east Australia.
• Rare stratospheric warming over Antarctica: Temperatures were 30°C to 40°C higher than normal in the region 10 to 50 km from Earth’s surface — another extraordinary weather event that could have contributed to the unusual heat and dryness in Australia.
• Link with climate change: Experts say climate change has worsened the scope and impact of natural disasters such as fires and floods. Weather conditions are growing more extreme, and for years, the fires have been starting earlier in the season and spreading with greater intensity.