Wednesday, December 11, 2019

NSW Bush Fires - Any Climate signal? Not really

There seems to be a bit of hysteria about the NSW Bushfires at the moment. People starting to blame climate change as always for this years intense fire season.

Not sure why. The IPCC has been pretty clear that there is only medium confidence that fire weather is increasing as a result of climate change. When you think that bush fires are dependent on a whole host of factors (fire weather, humidity, precipitation, human activity, wind) and only one of those is really degraded by climate change, it doesn't make sense.

So I figured I would go to the stats and see if NSW bush fire activity has increased as a result of the increased temperatures. Using areas burnt as a proxy, and getting my data from the NSW RFS annual reports and NSW Parliament (https://apo.org.au/sites/default/files/resource-files/2014/06/apo-nid40238-1132401.pdf), I get the following data about bush fires since 1926.


Just from the stats, it looks like the years fires are no unprecendented, and that the fires of 1952 in NSW far outweigh the recent activity. So much of climate change hysteria is memory failure.

There IS a trend increase detected of 1550 extra hectares per year (based on current 2019/2020 year of 2 million hectares burnt) but it is not statistically significant. See Regression of the trend output below



So no statistically significant change in Bushfire activity over close to 100 years (even though warming has increased)

To blame climate change for the recent NSW bushfire activity is again, bad science.