Fires, Polar Bears and Global Warming
Recently, there have been several destructive wildfires in Canada and the United States. Of course, many people blame climate change for these disasters. Others blame arson, or even space lasers. But the real cause of wildfires is the accumulation of fuel.
People are not very good at understanding things on large scales. They are pretty good at understanding proximate causes, such as how a discarded cigarette or a lightning strike can start a fire. But they are terrible at understanding long-term processes and large-scale systems. People are blind to a lot of reality.
When I think about the human inability to understand nature, a certain event comes to mind. In 2017, a video of a dying polar bear went viral. Of course, it was linked to a moral narrative: GLOBAL WARMING IS KILLING THE POLAR BEARS!!!
This is a good test of your ability to think abstractly. If you can think about systems and processes in the abstract, you should immediately recognize the fallacy involved in linking one polar bear’s death to global warming.
First, every polar bear dies. Yep, every single one. So, if polar bears are thriving as a species (if their population is large) then more individual polar bears will be dying. Dying polar bears are not evidence that the polar bear population is in decline. The exact opposite is true.
Every polar bear death is horrific, by our standards. They don’t die hidden away in hospitals, numbed by opiate drugs. Some bears die from predation (mostly by other bears). Some die from accidents on the ice. Some are killed by human hunters. The life of a polar bear is tough. They hunt seals and other marine mammals on the sea ice. Those that live long enough eventually become too injured to hunt and die of starvation.
If there is a thriving population of polar bears, then you will see more old, injured bears dying from starvation. That doesn’t fit human intuitions about “thriving”, of course. We didn’t evolve to think on the scale of a species or an ecosystem. But that’s how nature works.
The polar bear population has grown in recent years, due to a reduction in hunting. Global warming might eventually cause some loss of habitat, but so far that hasn’t been a huge issue.
To their credit, National Geographic eventually admitted that they were wrong to present this animal’s death as due to climate change. Essentially, they admitted that it was misleading propaganda.
Global warming is a long-term process with large-scale effects. It can only be understood in abstract terms. The only relevant evidence is statistical. A single polar bear’s death has nothing to do with global warming. It is utterly irrelevant. But it has a much bigger emotional impact on most people than statistics. People can emotionally relate to a dying bear. They can feel sympathy for the bear, and anger that humans are causing the poor bear to die.
This is stupid, of course, but most people are stupid. I mean, they can read and write and add numbers and drive a car and shop at the grocery store, etc, but they can’t understand anything on a large scale of space, time or complexity. They can’t think abstractly. They can never grasp how nature works. They can see the trees, but they can’t conceptualize the forest. They can see one dying polar bear, but they can’t understand population dynamics and ecosystems.
The same cognitive limitations prevent most people from understanding the real cause of wildfires, and being rational about them.
Plants pull carbon out of the air, and use it to create various carbon-chain molecules, such as cellulose and lignin, the primary constituents of wood. For the system to be balanced, and not just accumulate carbon indefinitely, the carbon must eventually return to the air as carbon dioxide. There are two ways that this can happen. One is by decomposition: fungi and bacteria can break down the carbon chains into smaller molecules, and then use them as an energy source. The other is by fire: the carbon can accumulate in living and dead vegetation over time, and then eventually be returned to the atmosphere by burning.
(The cycle also involves hydrogen, but for simplicity let’s focus on carbon.)
The carbon doesn’t always return to the atmosphere in a short period of time (hundreds of years or so). It can accumulate in peat or other deposits. In that case, it can be sequestered for hundreds of millions of years. That’s where coal comes from. But most returns to the atmosphere within a hundred years or so, by decomposition or burning.
Some forests in North America are quite wet. In those forests, fire is rare, and decomposition is the natural way that carbon returns to the atmosphere. Along the Pacific coast, from Alaska to Northern California, there is a strip of temperate rainforest. It rarely burns, and can form a climax ecosystem that is stable for thousands of years. On the forest floor, fungi and bacteria slowly break down and oxidize the dead vegetation. The redwood forest of northwestern California is a famous example of that climax ecosystem. Eastern North America also has climax forests that don’t burn easily.
But in many other places, there is a natural cycle of fire and regrowth. Most of the boreal forest is like that. It is too dry and cold for much decomposition to take place. Instead, it burns every 50 to 100 years. The boreal forest has fire-adapted tree species, such as jack pines and black spruce, that use the rising air and wind created by fire to spread their seeds. Their cones open in the heat of a fire.
In valleys from central British Columbia south to California, there is a semi-arid landscape dominated by bunchgrass, sagebrush and ponderosa pine. At higher elevations, there are dry forests of Douglas fir and lodgepole pine. East of the Rocky Mountains, there are similar dry parklands and grasslands. Those ecosystems have a natural cycle of growth and destruction by fire.
In the past, humans increased the frequency of burning in many parts of North America. The natives used fire to clear away dense forests and brush, opening up the landscape for travel and for grazing by bison and elk. Humans like open landscapes, not dense forests. After European contact, the native population collapsed due to disease. That caused a reduction in burning. Dense forests replaced grasslands and parklands in some areas.
Modern fire suppression began after WW2. People developed the belief that forest fires were unnatural and harmful. Smokey Bear told a generation of children that they could and should prevent forest fires. This attitude prevailed for a long time, although it is now starting to change.
In many cases, there are good reasons for fire suppression. Fires can destroy valuable timber, kill livestock, destroy buildings, and even kill people. But fire suppression created a type of ecological “debt”: the accumulation of fuel, especially in areas near human habitation. After 70+ years of fire suppression, there is a lot of fuel in certain places.
Global warming could cause an increase in burning in some areas. Here in British Columbia, we have had hotter and drier summers lately. That could be due to global warming, and it does make catastrophic fires more likely to occur now.
However, fires will eventually occur in places like the Fraser canyon and the Okanagan valley with or without global warming. Those places have been semi-arid for thousands of years, and they have burned on a regular basis for all that time. The same is true for the area near Yellowknife, Northwest Territories, where large fires are now burning. That area has accumulated a lot of fuel, and fires were inevitable.
There is a rational approach to living in fire-prone ecosystems. First, you accept that fire is part of the natural cycle. Second, you create low-fuel areas around human habitation, by clearing forest, or at least thinning it, and doing controlled burns. You plan to fight fires along this perimeter, not in residential areas.
Unfortunately, those things have not been done in most communities. Instead, suburbs have sprawled into fire-prone ecosystems. West Kelowna is a perfect example of this. A recent fire there destroyed about 200 structures. Luckily, no one was killed in that fire.
Global warming could change some ecosystems, making them more fire-prone. However, that is not the main reason for the recent fires in British Columbia and the Northwest Territories. The fires are burning in naturally fire-prone ecosystems, where fire is inevitable in the long run.
It is rational to be concerned about global warming, if you can understand it. But most people can’t actually think about something like that. It’s too big. It’s global. So, they attach the term “global warming” to things that they can grasp and emotionally relate to, such as a single dying polar bear or a wildfire. Instead of being a rational concern, “global warming” becomes an ideological lens that gives events moral significance.