The current furor about an alleged connection between climate change, CO2 emissions, and Australian fires finds no support in the scientific literature. According to scientists, rising CO2 concentrations reduce fire ignition and burned area. Further, both global-scale and Australian fires were far more pervasive during the colder Little Ice Age.
Here’s what the scientific literature has to say about fires and their connection to climate and CO2 concentrations.
1. “Elevated CO2 and warmer climate promote global total tree cover” and higher CO2 “leads to reduced fire ignition and burned area” (Chen et al., 2019).
2. Globally, fires were much more common during the colder Little Ice Age (Yang et al., 2007; Ward et al., 2018; Doerr and Santin, 2016), or before 1900. Fire frequencies have been rapidly declining as CO2 emissions began abruptly rising in the 1940s.
3. There has been a continued decline in global fire since the 21st century began (Earl and Simmonds, 2018).
4. Australia’s mainland experienced far more pervasive fire during the 1800s to early 1900s, or the Little Ice Age. There has been an abrupt decline in fire activity for the entire Australasian region in the last 50 years (Mooney et al., 2011).
5. The “assumed positive relationship between drier climates and biomass burning” is not supported by wetter Little Ice Age climates coeval with more burned area in Australia (Tibby et al., 2018).
6. Australia, like the globe, has neither become wetter or drier over the last 3 decades. There is “no evidence” global precipitation patterns have been been altered by global or regional temperature changes (Nguyen et al., 2018).
To summarize, the scientific literature does not lend support to claims fires in Australia are connected to warming, rising CO2 emissions, dry climates, or wet climates.
If there were a potential climate linkage, it would be that enhanced fire activity arises in cooler climates.
In other words, there is no apparent link to anthropogenic global warming that can be supported by evidence found in the scientific literature.