The Australian bushfires this year has become a serious global concern because of its severity and the scale of its damage and impacts on people, animals, ecosystems, properties, and the land itself.
Bushfires are a seasonal event in Australia and can even be beneficial to ecosystems if managed and controlled – a practice that Indigenous Australians used many years ago. However, this year it is has gone out of proportion that scientists factored in climate change.
What is the climate in Australia in 2019?
To get a clearer picture of what has contributed to these bushfires this year Australian government through its Bureau of Meteorology released Australia’s climate statement for 2019.
Annual climate statement (2020) summarises:
- 2019 is the warmest year on record, with a mean temperature of 1.52°C above average all over the country.
- A widespread of record warm temperatures all throughout the year and occurrence of heatwaves in January and December.
- It is also the driest year on record, rainfall is 40 per cent below average.
- Droughts were particularly severe in New South Wales and southern Queensland.
- There’s been widespread severe fire weather throughout the year, the Forest Fire Danger Index highest since 1950, and the strongest positive Indian Ocean Dipole (IOD) on record.
What is the Indian Ocean Dipole?
Indian Ocean sea surface temperature impacts rainfall and temperature patterns over Australia. Sustained differences in sea surface temperatures in the tropical western and eastern Indian Ocean is known as the Indian Ocean Dipole (IOD). It is the key driver of the climate in Australia and can affect agriculture because it coincides with the winter crop growing season. It has 3 phases: neutral, positive, and negative (Indian Ocean influences, 2020).
Indian Ocean influences (2020) explains further:
- Neutral IOD is when the water from the Pacific flows through Indonesia keeping the Northwest seas of Australia warm. Air rise and falls on the western half of the Indian Ocean basis blowing westerly winds along the equator. Temperatures are close to normal hence there is little change in the Australian climate.
- Positive IOD occurs when westerly winds weaken in the equator, warm water moves towards Africa, and cool water moves towards the east on around Indonesia and just above the northwest of Australia, creating a cooler than normal water in the east and warmer waters in the west. This creates less rain or moisture in north-west Australia and less rainfall and high temperatures over parts of Australia in winter and springtime.
- Negative IOD, when there is a strong westerly wind in the equator, allowing warmer waters to stay near Australia, warmer water in the east and cooler waters in the west. This results in more rainfall in the southern parts of Australia and more available moisture across the country.
- The bureau of meteorology records shows that since 1960 to 2016, there have been 11 negative IOD and 10 positive IOD’s recorded. Showing almost an alternating negative and positive IOD’s every year.
What’s the connection between the Indian Ocean Dipole and Bushfires in Australia?
Global heating is supercharging an increasingly dangerous climate mechanism in the Indian ocean that has played a role in the Australian bushfires and floods in Africa, the Guarding article reads (Beaumont & Readfearn, 2019).
Scientist says that this year’s record Indian Ocean Dipole particularly the strong positive IOD will be a phenomenon that will reappear more regularly as sea temperature increases (Beaumont & Readfearn, 2019).
This, of course, means that the Australian climate of 2019, will recur, which imply more droughts, drier days, and more chances of extreme bushfires.
Australian climatologists also say that this year’s dipole is at least one of the contributing factors in the bushfires. Jonathan Pollock of Australia’s Bureau of Meteorology says that the dipole as was one of the strongest on record (Beaumont & Readfearn, 2019).
We believe that the Australian authorities are engaged actively in risk management of bushfire events, particularly factoring in the changing climate patterns. Surely, climate adaptation strategies are needed to make life and existence sustainable in bushfire-prone areas of Australia.
Fire. (2018). WWF Australia. Retrieved from https://www.wwf.org.au/what-we-do/species/fire#gs.w83ys7
Australia’s Climate in 2019. (2020, January 9). Annual climate statement 2019. Australian Government Bureau of Meteorology. Retrieved from http://www.bom.gov.au/climate/current/annual/aus/2019/#tabs=Maps
Indian Ocean influences on Australian climate. (2020). Australian Government Bureau of Meteorology. Retrieved from http://www.bom.gov.au/climate/iod/#tabs=Indian-Ocean-climate-drivers
Beaumont, P. & Readfearn, G. (2019, November 19). Global heating supercharging Indian ocean climate system. The Guardian. Retrieved from https://www.theguardian.com/global-development/2019/nov/19/global-heating-supercharging-indian-ocean-dipole-climate-system
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