| The McKitrick article: Ross McKitrick: The truth about forest fires goes up in climate-change smoke, by Ross McKitrick, “Special to Financial Post” Published Jun 15, 2023.In a nutshell, says McKitrick: “We’re told we should listen to the science, but the science on forest fires is that they peaked in the 1980s”
McKitrick makes some bold jabs at folks saying there are links to climate change: “…Unfortunately, politicians, reporters and climate activists rushed in to exploit this unusual event by pushing their agenda. They made a lot of glib claims about climate change causing wildfires to become more common. For instance, Prime Minister Trudeau tweeted: “We’re seeing more and more of these fires because of climate change. That statement is false. Amid the smokescreen of untrue claims, nobody seems to have bothered looking up the numbers. Canadian forest fire data are available from the Wildland Fire Information System. Wildfires have been getting less frequent in Canada over the past 30 years. The annual number of fires grew from 1959 to 1990, peaking in 1989 at just over 12,000 that year, and has been trending down since. From 2017 to 2021 (the most recent interval available), there were about 5,500 fires per year, half the average from 1987 to 1991.” he does seem to concede that there has been some trend to more aggressive fires in some situations which he attributes to fire suppression allowing some buildup of fuel.
Within 7 hours, some critical alternative perspectives are given in the comment section; a selection:
(There were also some comments that are better not published anywhere)
Geoffrey Pounder
1 HR AGO
McKitrick: “Wildfires have been getting less frequent in Canada over the past 30 years.”
Cherry-picking. Fire activity over recent decades is hugely variable over time and space.
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McKitrick: “And 2020 marked the lowest point on record with only 760,000 hectares burned.”
Given the huge interannual variability, you cannot base an argument on single years. More cherry-picking.
Since 1960, 1970, 1980, and 1990, the trends for annual area burned and the number of large fires in Canada are positive. Particularly, in the West.
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Divide the reporting interval in two halves:
Interval………Avg Annual # of Fires…Avg Annual Area Burned (MMha)
1959–1990…………5,958………………………………1.6
1990-2021………….7,124………………….……………2.5
An increase in Area Burned of 1.5x nationally.
Alberta likewise has seen a 1.5x increase.
Area Burned in B.C. doubled over the same intervals.
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With the most recent data reported for 2021, the “past thirty years” takes us back to 1992. Indeed, the trend is negative. Back up a couple of years to 1990 and the trend is positive. Moving the starting point a year or two forward or back to get the result you want is playing with statistics.
Three big spikes (1989, 1994-95) boost the 1990s’ average Area Burned (and thus reduce the thirty-year trend), but by definition anomalies do not define the trend, but lie outside it.
Geoffrey Pounder
1 HR AGO
Reply to Geoffrey Pounder
The national trend obscures regional differences. If the West dries out and the East gets wetter, those regional trends offset one another. The trends in the West are dramatic.
Check out the data for BC and AB. Big change in the last decade. Especially in B.C..
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2018 was B.C.’s worst wildfire season on record. Breaking the record set in 2017.
5 of the top 10 fire seasons in B.C. (area burned, since 1950) occurred since 2010.
Summer 2021 marked the third time in five years that B.C. saw more than half a million hectares burn in a wildfire season. In the 70 years prior to 2017, it only happened once.
B.C.’s forest management practices have not changed dramatically in the last 5 years. But the weather has.
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In terms of large-fire share, the average over the two halves of the dataset is virtually unchanged at 4.35% and 4.53% respectively. A non-issue.
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Werner Kurz, NRCan forest scientist: “While the number of fires has declined in recent decades, the far more important indicator, area burned has increased. There are many publications from Canada, North America and elsewhere that clearly substantiate the fact that climate change has increased the area burned. In both BC and California the most severe impacts of fires ever recorded occurred in 2018, and there are numerous other examples from around the world. Moreover, there are numerous publications that have demonstrated that anthropogenic climate change is the primary driver of increased area burned and forecasts are for (regionally-differentiated) further increases.”
Geoffrey Pounder
1 HR AGO
Reply to Geoffrey Pounder
Climate disinformers fail to distinguish between a decrease in human-set fires in GRASSLAND in the tropics and an increase in FOREST fire (area burned, number of large fires).
Globally, the trend in the number of fires is down, because humans in developing nations, especially in Africa, are setting fewer fires in grassland to clear land:
“NASA Detects Drop in Global Fires: “Using NASA satellites to detect fires and burn scars from space, researchers have found that an ongoing transition from nomadic cultures to settled lifestyles and intensifying agriculture has led to a steep drop in the use of fire for land clearing and an overall drop in natural and human-caused fires worldwide.”
IPCC Special Report on Climate Change and Land (SRCCL): “Global land area burned has declined in recent decades, mainly due to less burning in grasslands and savannahs (high confidence).”
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“Emergence” is the point in time at which changes in a given (climate) phenomenon clear the bar of natural variability, pointing clearly to climate change as the driver.
If natural variability is high, the signal is noisy, and it takes longer for a clear climate signal to emerge. Such is the case for wildfire.
Lack of emergence does NOT mean x is not happening or will not happen. It means scientists do not have sufficient data yet about this highly variable phenomena to draw a definitive conclusion. The climate trend, if any, has yet to emerge from the signal noise.
View the profile of “Geoffrey Pounder”
Geoffrey Pounder
1 HR AGO
Reply to Geoffrey Pounder
The IPCC projects increasing fire risk as the world warms: “Climate change is playing an increasing role in determining wildfire regimes alongside human activity (medium confidence), with future climate variability expected to enhance the risk and severity of wildfires in many biomes such as tropical rainforests (high confidence).”
Detection may lag projection by decades. Just because a climate signal has not been detected yet is not cause for inaction. That’s why science is useful. Science can predict things, and we can avoid them.
The link between climate, fire weather, and fire activity is incontrovertible. Which does not mean that climate is the only determinant of fire behavior. A straw-man argument that no fire scientist makes.
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Do you expect more or less wildfire in a warming world?
Rising temperatures, warmer winters, more severe pine beetle infestations (feedback), more drought, mass tree mortality, increasing fuel load, more lightning, more heat waves, earlier springs, more rapid snow melt, more precipitation falling as rain and less snow… All lead to longer fire seasons and more intense fires.
Globally, and in Canada, in Western Canada, including B.C., but not Alberta, the number of human-set fires has decreased in recent decades, while area burned increases. Fire season is also lengthening.
Regardless of ignition source, what determines the spread and intensity of fires is local fire conditions. Including fuel load and fire weather. To reduce fire risk to humans, we need to tackle these twin challenges together.
Craig Jowett
1 HR AGO
https://natural-resources.canada.ca/our-natural-resources/forests/state-canadas-forests-report/disturbance-canadas-forests/16502#fires
CJ Picek
4 HRS AGO
Here is some actual journalism on this question:
https://thenarwhal.ca/wildfire-canada-explainer/
Arthur Groot
4 HRS AGO
Mr. McKitrick is blowing smoke in this article. He states that the annual area burned in Canada peaked thirty years ago. This is untrue. The most recent decade has had the greatest area burned. Here are the ten year averages for area burned from the Canadian National Fire Database:
2012-2021 2.8 million ha
2002-2011 2.2 million ha
1992-2001 2.7 million ha
1982-1991 1.9 million ha
1972-1981 2.2 million ha
1962-1971 0.9 million ha
For the entire period covered in the database there is a statistically significant trend to increasing annual area burned. The area burned in 2023 will make this trend more pronounced.
McKitrick also states that the lowest area burned occurred in in 2020. This is untrue; the areas burned in 1963 and 1965 were lower.
For a peer-reviewed analysis of Canada wildland fire data see: https://cdnsciencepub.com/doi/full/10.1139/cjfr-2018-0293 |
