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.
Now significant figures protocols are something every science student learns in first year and with the exception of analytical chemists and engineers they proceed to ignore for the remainder of their careers. The critical thing we teach first year students is that all measurements have a degree of uncertainty and that uncertainty has to be considered when attributing blame for an event. Let’s now consider the change in temperatures associated with the Super El Nino. As described at Wikipedia (yes I’m being lazy and using Wikipedia) “on May 3, the temperature climbed to 32.8 degrees Celsius accompanied by relative humidity as low as 12%. The situation intensified on May 4 when temperatures reached 31.9 degrees Celsius and winds gusted to 72 km/h”. We are talking about temperatures ranges over 20 degrees Celsius above the climate normals for May in Fort McMurray and winds that are not even on the charts.
I have yet to see any attribution of high wind speeds in Alberta on climate change so let’s start by stating that the winds (which dried the forests and fed the fire) are 100% the result of El Nino and not climate change. As for the estimates of the effect of climate change on temperature; I’ve seen estimates from as low as 0.85 degrees Celsius to just over 1 degree Celsius. So at best the temperature increase might represent less than 5% of the El Nino effect. Combining the two we have a temperature effect of less than 5% and a wind effect of zero percent. That is the definition of not significant in my book. For some, however, that tiny possible incremental increase might be considered enough to claim victory. That of course assumes that climate change actually had a negative effect on the state of the forests in Alberta. As for that topic:
What does the science say about climate changes effects on forests to date in Alberta
The funniest part of this whole adventure had to be an exchange I had today with one of my biggest detractors. This individual has stalked my every discussion thread adding his/her two cents. This individual is clearly not schooled in the scientific method and is one of the people who keeps insisting that I prove that climate change did not have an effect on the fire.
As “proof” that I was wrong this individual provided me with a link to a recent paper Climate-induced variations in global wildfire danger from 1979 to 2013. The paper’s abstract reads like it should provide overwhelming support for the premise that climate change had an effect on the fire. Now happily for me I had previously read the paper and that was important in this case. You see there is an issue I have noticed in this generation of climate activists and journalists: they depend on media guides and abstracts rather than reading the full papers themselves. As a young scientist I was always reminded that there is a reason why we write and read papers and not just the abstracts and that is because the paper is where the information is and the abstract is not designed to provide the full nuance of a paper.
While the general finding of the research was “an 18.7% increase in global mean fire weather season length” this represented a mean value and did not actually reflect all portions of the map. A careful read of the paper actually shows that in Alberta (and the Fort McMurray area), the effects of climate change was actually a decrease in fire weather season length. For those who wonder where I get that look at Figure 3a in the article. Some might argue that Fig 3b shows a possible increase in the last few years (depending on the pixel size) but reading the figure information you see that the “increase” is simply an increase in the second half of the period as compared to the first half. The net effect over the period from 1979 through 2013 was negative. This would explain to the activists why Natural Resources Canada (NRC) says:
This complex combination of influences makes it difficult to identify clearly whether any measurable changes in the patterns of wildland fire over the last few decades can be linked directly to climate change. Nevertheless, pattern changes do appear to be underway.
In Canada’s northwestern boreal regions, for example, the annual amount of forest area burned by wildland fires rose steadily over the second half of the 20th century. Some of this increase has been attributed to climate change.
By contrast, in Canada’s southern boreal forest, the annual amount of area burned seems to have decreased during the 20th century. This trend might be the result of climate change causing greater amounts of precipitation over time in these regions.
However, analyses of fire history suggest that it is the effect of climate variability on precipitation regimes that is the primary reason for the decreasing fire activity in southern regions.
For those of you who refuse to read quotes let me paraphrase. Irrespective of what you may have heard about the boreal forests in general, you have to remember that the boreal forests cover up to 55% of Canada’s land mass and a lot changes over that 55%. What that means is that even if large parts of the boreal forests are drying up, the specific portions of the boreal forest in question, (i.e. near Fort McMurray) have not necessarily been doing so. Now look at Tables 3 and 5 of the paper, both showed an absence of an effect for North American boreal forest. That is what the research says, not me Blair King environmental scientist, but the specialists in the field. The research says that in Fort McMurray the effects of climate change since 1973 has been a shortening of the average fire season and wetter than average conditions. Once again that is what the science has been saying not me. It is not as if the scientists have been hiding these facts, the NRC put it right out there on their web site. So when I write that climate change did not cause the fire that is what I mean and it is not because I say so but because that is what the science says.
Let’s conclude this post where my earliest blog post began. Let’s go back to what Dr. Flannigan has said on the topic. As I have written, Dr. Flannigan has been very careful with his language and has repeatedly stated: “it’s impossible for scientists to say global warming caused this specific fire” and “this is an example of what we expect — and consistent with what we expect for climate change.” His wording was carefully chosen and deliberate. It presents a warning about future conditions while making no claims about current conditions. There is a reason why an expert in the field says such things. Because it is true. So even as the commentariat and the climate activists have attempted to reverse the onus of proof and ignored the scientific method the data was out there all along. I will say this again so that no one can call me a “denier”. Climate change is real and over the long term it will likely result in an increase in fire risk in Alberta’s boreal forests. But 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. Now you can understand why 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 and not climate change.