Yesterday not a single drop of rain fell on continental Australia. The Bureau of Meteorology was unable to identify any other day where this had happened before. It is a pattern of unrelenting dry conditions and wildfire that have been plaguing the country for months, and the bone-dry conditions are predicted to persist through the summer. There is a possibility that these unprecedented conditions were set in motion by a stratospheric warming event over Antarctica.
Impacts from this stratospheric warming are likely to reach Earth’s surface in the next month and possibly extend through to January.
Apart from warming the Antarctic region, the most notable effect will be a shift of the Southern Ocean westerly winds towards the Equator.
For regions directly in the path of the strongest westerlies, which includes western Tasmania, New Zealand’s South Island, and Patagonia in South America, this generally results in more storminess and rainfall, and colder temperatures.
But for subtropical Australia, which largely sits north of the main belt of westerlies, the shift results in reduced rainfall, clearer skies, and warmer temperatures.
Today, the cities of Sydney, Wollongong and, Newcastle are threatened by bushfires so intense that a new warning system was put in place for the first time in the city’s history. The fires have reached the suburbs, and erratic weather conditions threaten most of eastern Australia. Urban citizens were warned of catastrophic damage from smoke and fire and that they should prepare themselves for a worst-case scenario.
Citizens of Sydney woke up to smoky conditions but, calm conditions with only two infernos nearby. That will change this afternoon and tonight, where over 100,000 homes are in danger of combustion.
The wind is picking up in eastern #Australia and may spread the disastrous wildfires. The fire danger extends over #Queensland and #NewSouthWales and the officials have raised the danger level to catastrophic near #Sydney. #Australiafire #Australiabushfires pic.twitter.com/DupP5lc7bV
— Foreca (@foreca) November 11, 2019
Hyperlapse of the #NSWfires from QF12 taken from 8:50-9:20am 12/11/19 from Lismore to the Hunter Valley.
All under extreme and catastrophic fire weather danger today. ✈️ altitude was 12km, really hoping the plumes don't reach this altitude later today, but that's very possible. pic.twitter.com/BAmo7qzmph
— Nick McCarthy (@mccarthy_nfm) November 11, 2019
The NSW Rural Fire Service (RFS) has warned Tuesday’s bushfire risk for the Greater Sydney and Greater Hunter areas is set to be “catastrophic”.
It is the first time the Sydney region has been rated at that level since the new fire danger ratings were introduced in 2009.
The RFS has issued a strong warning that “lives and homes will be at risk” as high temperatures, strong winds and low humidity combine to create fierce conditions.
It has advised people in areas at risk to head to larger towns, shopping centres or facilities away from bushland areas.
Schools in high risk areas will also be closed on Monday and Tuesday.
Elsewhere, danger warnings at “extreme” level are in place for Tuesday for the North Coast, Illawrra and Shoalhaven, Central Rangers, Northern Slopes and the north–western area.
Danger in the Far North Coast, New England, Far South Coast, Southern Ranges and Lower Central West Plains has been rated as “severe”.
— FLHSGeography (@FLHSGeography) November 10, 2019
Scott Morrison, clearly realising there is a sizeable portion of the population who care somewhat about the fact the planet is cooking underneath our feet, today announced a blockbuster new ‘direct action’ climate change policy, which weirdly is exactly the same as Tony Abbott‘s one from several years ago, just with a new name. This is incredible gear!
Morrison – who presides over a government packed with dudes who know full well that they’ll be dead and buried before the worst effects of climate change hit, and therefore have absolutely no intention of doing anything about it – announced he will revive the so-called Emissions Reduction Fund, promising a pretty paltry $2 billion of funds over 10 years.
Does this “climate solutions fund” involve cutting back on coal production and making real, meaningful and most importantly structural efforts to reduce emissions? Haha fuck nah it doesn’t.
— Tom Red (@TomRed43) November 9, 2019
The link between rising greenhouse gas emissions and increased bushfire risk is complex but, according to major science agencies, clear. Climate change does not create bushfires but it can and does make them worse. A number of factors contribute to bushfire risk, including temperature, fuel load, dryness, wind speed and humidity.
The Bureau of Meteorology and the CSIRO say Australia has warmed by 1C since 1910 and temperatures will increase in the future. The Intergovernmental Panel on Climate Change says it is extremely likely increased atmospheric concentrations of greenhouse gases since the mid-20th century is the main reason it is getting hotter. The Bushfire and Natural Hazards research centre says the variability of normal events sits on top of that. Warmer weather increases the number of days each year on which there is high or extreme bushfire risk.
Dry fuel load – the amount of forest and scrub available to burn – has been linked to rising emissions. Under the right conditions, carbon dioxide acts as a kind of fertiliser that increases plant growth.
— Douglas MacDonald (@dmac5dmark2) November 12, 2019
Dryness is more complicated. Complex computer models have not found a consistent climate change signal linked to rising CO2 in the decline in rain that has produced the current eastern Australian drought. But higher temperatures accelerate evaporation. They also extend the growing season for vegetation in many regions, leading to greater transpiration (the process by which water is drawn from the soil and evaporated from plant leaves and flowers). The result is that soils, vegetation and the air may be drier than they would have been with the same amount of rainfall in the past.
The year coming into the 2019-20 summer has been unusually warm and dry for large parts of Australia. Above-average temperatures now occur most years and 2019 had the fifth-driest start to the year on record, and the driest since 1970. Australia recorded its hottest month in January 2019, its third-hottest July and its hottest October day in some areas, among other temperature records.