In 2016 the science says that the net effect of climate change has been a decrease in fire season length and wetter than average conditions. These are not the conditions that enhance fire risk, they reduce fire risk.
Forested area burned in Canada, 1918–2005 (dashed line); spring–summer PDO index, 1900–2005 (continuous line). Thick lines represent the 7-year running means in order to highlight low frequency variability (black, PDO; grey, area burned). Note the overall high similarity between both series at low frequencies.
As regular readers of my blog know, I have spent the last few days being lambasted by any number of climate activists, social scientists and Google experts about my examination of the science behind the cause of the fire in Fort McMurray. As I discuss in my Huffington Post blog We Can’t Blame Climate Change For The Fort McMurray Fires the scientific consensus is forming around a combination of a Super El Nino and poor forest management practices as being the cause of the fire. Throughout this virtual flaying I have come to recognize that the majority of the people who have spent this week insulting me, and apparently a number of the people writing articles about the fire, have very little understanding of the scientific method. The rest of this blog post will provide a back-up for that very broad statement.
Let’s start with the obvious thing readers should understand about the scientific method. When someone proposes a hypothesis then it is up to them to provide the evidence to support that hypothesis. So when all these pundits suggested that climate change was the cause of the forest fire in Fort McMurray, it was up to them to demonstrate why that was the case. It was not up to me to prove otherwise. However, that was not what we saw in the discussions to date. The consensus among the commentariat was that since I differed from their general agreement that I was somehow responsible for proving that climate change was not the fundamental cause of the fire. That is not how science works and thus I was a bit surprised when a number of scientists jumped on the bandwagon demanding that I support my position. Happily for me, I had the data on my side.
In my posts, I have provided the information that has been used by the forest scientists to suggest that climate change was not a significant factor in the fire. I have pointed out how the warm, dry Alberta winter had been long predicted by the research community based on the El Nino modelling. As I have also pointed out, the pre-eminent expert in the field of El Nino modelling made the very specific statement that:
There is no conclusive evidence that the occurrence of El Nino (frequency and intensity) is influenced by climate change…El Nino occurrences did not switch in frequency or intensity due to climate change.
Lacking a need to pile on I didn’t go into detail about how this year actually represented a Super El Nino and how the failed El Nino of 2014 actually started the process of drying out the forests a year earlier. I didn’t point out that when the Super El Nino hit in 2015 the ground was unusually dry even for the start of an El Nino year. Moreover, because this year represents a Super El Nino the heating was even greater than ever, resulting in record temperatures that can be directly attributed to the El Nino (and not climate change). In my post I also provided the results of the Flat Top Complex Wildfire Review Committee Report which warned that the forest management practices of the past had increased the risk of large and potentially costly catastrophic wildfires. Considering that the trees surrounding Fort McMurray are hard-wired for fire combining the effects of the 2015 Super El Nino and the failed forest management practices of the past, the forests were ready to burn and burn they did.
The response of the non-science-trained commentariat was that I had failed to prove that climate change did not have even the smallest additive effect on the El Nino or on the state of the forests prior to the fire. Now as I have already pointed out, it is not my responsibility to prove a negative, but let’s be generous and continue this with a discussion of the concept of significant figures.