Dr Niels Andela, NASA Goddard Space Flight Center and a collaborator in the Global Fire Emissions Database (GFED) , has estimated from satellite data that in the period 1 August 2019 – 13 December 2019 the NSW bushfires have emitted 195 Mt CO2-equivalent (CO2-e) and the Queensland fires another 55 Mt CO2-e . Australia’s annual carbon pollution was 532 Mt CO2-e [1].
However the Sydney Morning Herald based on updated estimates from Dr Pep Canadell, a senior research scientist for CSIRO and the executive director of the Global Carbon Project (2 January 2020): “Australia's annual industrial emissions budget in 2018-19 was 532 million tonnes of carbon dioxide equivalent. This season's bushfires, which have burnt through more than 5 million hectares across the country, are estimated to have released two-thirds of this amount - or about 350 million tonnes - of carbon dioxide into the atmosphere so far. Until recently, Australia's forests were thought to reabsorb all the carbon released in bushfires, meaning they achieved net zero emissions. But scientists say climate change, drought and escalating fires combined are reducing forests' ability to reabsorb carbon… The 350 million tonne figure was extrapolated from data on NASA's Global Fire Emissions Database issued two weeks ago for NSW's bushfires, which at that stage had burnt 2.7 million hectares and emitted 190 million tonnes of carbon dioxide” [2].
However Wikipedia reports that as of 8 January 2020, in the Australian 2019–20 bushfire season 10.7 million hectares have burned since June 2019 (a bushfire season of 10 months rather than the previous Spring-Summer norm of 6 months)[3].
Accordingly total bushfire emissions = 190 Mt CO2-e x 10.7 Mha/ 2.7 Mha = 753 Mt CO2-e or 1.4 times Australia’s annual CO2-e emissions (ditto, 350 Mt CO2-e x 10.7 Mha/ 5 Mha = 749 Mt CO2-e) i.e. Australia’s total emissions jumped this 2019/20 financial year from 532 Mt CO2-e to 532 Mt CO2-e + 753 Mt CO2-e = 1,285 Mt CO2-e with 6 months to go.
However missing in this accounting is the immense and prolonged loss of photosynthetic CO2 capture capacity by South East Australian eucalyptus forests that can be the best forest carbon sinks in the world as reported by Keith et al. (2009): “From analysis of published global site biomass data (n = 136) from primary forests, we discovered (i) the world's highest known total biomass carbon density (living plus dead) of 1,867 tonnes carbon per ha (average value from 13 sites) occurs in Australian temperate moist Eucalyptus regnans forest” [4].
Far more serious for humans is the long-term impact on health of prolonged exposure to elevated CO, N2O, NO2, SO2 and PM2.5, especially in smoke-blanketed, population dense Sydney, Canberra and Melbourne. 8 million people die world-wide from air pollution each year (WHO), with this including about 10,000 Londoners, 10,000 Australians and 75,000 people from the long-term effects of pollutants from the burning of Australia’s world-leading coal exports [5].
[1]. Graham Redfearn, “Australia’s bushfires have emitted 250 m tonnes of CO2, almost half of country’s annual emissions”, Guardian, 13 December 2019: https://www.theguardian.com/environment/2019/dec/13/australias-bushfires-have-emitted-250m-tonnes-of-co2-almost-half-of-countrys-annual-emissions .
[2]. Mike Foley, “Bushfires spew two-thirds of national carbon emissions in one season”, Sydney Morning Herald, 2 January 2020: https://www.smh.com.au/politics/federal/bushfires-spew-two-thirds-of-national-carbon-emissions-in-one-season-20200102-p53oez.html .
[3]. “2019-20 Australian bushfire season”, Wikipedia: https://en.wikipedia.org/wiki/2019%E2%80%9320_Australian_bushfire_season .
[4]. H. Keith, B.G. Mackey and D. B. Lindenmayer., “Re-evaluation of forest biomass carbon stocks and lessons from the world’s most carbon-dense forests”, PNAS, 14 July 2009, 106 (28) 11635-11640: https://www.pnas.org/content/106/28/11635 .
[5]. “Stop air pollution deaths”: https://sites.google.com/site/300orgsite/stop-air-pollution-deaths .