The Not-So-Positive Feedback Loop
Some observations about how certain complex systems have the ability to self-regulate.
In my last post, where I discuss the illogical Malthusian underpinnings of the modern environmentalist movement, I wrote something that came as a bit of a revelation at the time of writing:
It seems like an increasing population should lead to careless exploitation of Earth’s resources. But in fact, the socio-economic system that enables such population growth also tends to harbor the institutions that help preserve the environment for prolonged future use.
As I’ve given these sentences more thought, I believe they can be rephrased to have a broader scope of application:
The characteristics that enable spontaneously ordered complex systems to yield seemingly unsustainable results tend to also help preserve long term stability of the system.
Just like the modern socio-economic system has created an environment where humans can increase in population without decimating the Earth’s resources, there are other systems that similarly self-regulate. Such “spontaneously ordered” systems, like the climate or a free-market economy, might yield what looks like an unstable output when one of the inputs changes. But a lot of times, the properties that allow an input to create a seemingly unstable output are the same properties that dampen the response of the system and lead to its stability.
(If I’m losing you with the control theory jargon, hopefully I will start to make sense in a bit. If you haven’t already, it may help to take a look at one of my previous posts, The Illusion of Control Part 1).
This idea behind self-regulation is separate from what in economics is called diminishing marginal returns. With diminishing returns, each additional input leads to a diminished output. This prevents a runaway effect. When coupled with intrinsic self-regulation, a very stable system emerges as a result.
While pondering how the self-regulation concept manifests itself in the real world, a couple examples came to mind. One is the climate, which I will discuss here, and the other I will write about in a later post.
Climate Self-Regulation
One of the reasons that climate scientists are so afraid of anthropogenic global warming climate change is that they believe that humans are introducing a positive feedback loop into the system and therefore causing instability in the climate.
Here are two of the potential positive feedback loops that worry many scientists:
Humans release CO2 into the atmosphere. More CO2 in the atmosphere causes the Earth to warm. Humans in warm climates need a way to cool off and use air conditioning. The use of air conditioning requires more energy and leads to more CO2 pollution. The Earth warms. People get hot and use more AC. The AC uses more energy and leads to more CO2 pollution. The Earth warms, and so on.
More CO2 in the atmosphere causes the Earth to warm. Rising temperatures cause more water to evaporate and get trapped in the troposphere, the part of the atmosphere that is closest to Earth. Water in the troposphere traps more heat and causes temperatures to rise. Rising temperatures cause more water to evaporate and get trapped in the troposphere, and so on.
(By the way, the warming effects of water vapor in the troposphere is a subject of debate in the scientific community, but that does not keep some climate scientists from still including it in their models).
This all sounds terrible, but it it turns out there are some issues with these claims of positive feedback loops hurling us towards a climate catastrophe.
Firstly, there is the concept of diminishing returns. The more greenhouse gases that are put in the atmosphere, the slower the rate at which the Earth warms. If you don’t believe this is the case, try running the following experiment that you can do in the comfort of your own home.
Lay down for a nap in a cold room, and cover yourself with a nice thick blanket. The blanket insulates the heat that your body produces and warms you up. You are still a little cold, so you add a second blanket. This blanket also insulates your body heat, but not as much as the first blanket. You add a third, and a fourth, and so on until you have nine blankets on top of you. When you add a tenth blanket, you realize that the difference in warmth between the ninth and tenth blanket is minuscule compared to the difference between the first and second blanket. The addition of the second blanket had made a much bigger difference in how warm you became compared to the addition of the tenth blanket.
Just like the addition of an extra blanket does not warm you as much as the addition of the previous blanket, adding more CO2 into the air will not trap as much heat as the previously added CO2.
Diminishing returns helps keep temperatures at bay, but it is not the only thing keeping temperatures from spiraling out of control.
Warmer temperatures have an effect on how clouds are formed. More water vapor ends up in the troposphere as previously mentioned, producing more “warm” or liquid clouds. If you live in a colder climate, you may notice in winter how days with low-lying clouds tend to be warmer than clear days. That is because these warm clouds trap more heat.
It turns out though that warm clouds also last longer and block out more sun than high-elevation “cold” clouds. Those of you who have ever bothered to stand outside may have noticed how the sun’s rays have a hard time getting through thick low-lying clouds. You may have even noticed in summer how cloudy days are typically cooler than sunny days. With these two radical observations in mind, you may wonder how more “warm” clouds could possibly lead to the world burning up in a fiery furnace.
Some level-headed scientists have wondered the same thing. In a paper published last year in Nature, researchers pointed out how the higher reflectivity of warm clouds “reduces the solar flux absorbed by the Earth.” This in turn has a negative feedback effect resulting in more stable temperatures, as opposed to a positive feedback effect resulting in runaway temperatures. Yes, temperatures in many areas are rising, but the resulting climate tends to be temperate rather than excessively hot.
What is remarkable is how the system self-regulates. Although we are accused of “unnatural” behavior by burning fossil fuels, we are releasing a gas that was stored naturally in the Earth for millions of years and is essential for plant life. The change in the composition of the atmosphere warms the Earth, but this can have the effect of creating clouds that block out the sun, thereby cooling the Earth’s surface.
The natural characteristics of the system that seem to yield unstable behavior (change in atmospheric composition leads to warming) also tend to preserve the long term stability of the system (warming leads to a different change in atmospheric composition which leads to cooling).
The climate is a spontaneously ordered system. It existed long before we came to Earth. No one designs the hurricanes, ocean currents, blizzards, or heat waves. The climate is unpredictable and ever-changing, but despite this, life is able to continue as it has for millions of years. We should disabuse ourselves of the notion that such an ancient, enormous, and complex system is somehow fragile and that we are capable of sending it into a state of instability. Rather, we ought to observe and learn how this incredible system regulates itself so that we may better understand how to thrive and prosper in it.