Editor’s note: Marshall Brain – futurist, inventor, NCSU professor, writer and creator of “How Stuff Works” –  is a contributor to WRAL TechWire.  He’s also author of “The Doomsday Book: The Science Behind Humanity’s Greatest Threats.” Brain has written several posts recently about the threat of climate change. His exclusive columns written for TechWire are published on Fridays. 

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RALEIGH – The last three articles in this series have discussed climate change and the collapse of civilization:

  1. We have destroyed our ecosystem – now we await the collapse of civilization – https://wraltechwire.com/2023/09/29/just-how-bad-is-climate-change-its-worse-than-you-think-says-doomsday-author/
  2. Just how bad is climate change? It’s far worse than you think – https://wraltechwire.com/2023/09/29/just-how-bad-is-climate-change-its-worse-than-you-think-says-doomsday-author/
  3. How climate change will cause the collapse of civilization – https://wraltechwire.com/2023/10/06/doomsday-authors-analysis-how-climate-change-will-cause-the-collapse-of-civilization/

A question arises: If civilization is going to collapse, then when? Can we create a definitive timeline?

One possible answer is, “No.” Example: there is no definitive timeline for when the next big Magnitude 9 earthquake will hit on America’s West Coast. We can say with certainty that there will be an earthquake, but we cannot say exactly when. This video can help you understand why: https://www.youtube.com/watch?v=76b_WGzCI54

In the same way:

  • We cannot say exactly when a giant Category 5 hurricane will hit Miami
  • We cannot say exactly when the Thwaite’s glacier or similar glaciers in Antarctica will break free and start collapsing
  • We cannot say exactly when a major crop failure will occur in one of the Earth’s breadbasket regions

We know that these things will happen, but we cannot put an exact date on the calendar.

The other possible answer is, “Yes.” The focus of this article is, “How runaway climate change will cause the collapse of civilization.” In a runaway situation, things will change quite quickly – fast enough to predict the end date.

What is runaway climate change?

Let’s start by looking at a definition for runaway climate change:

Runaway Climate Change – https://encyclopedia.pub/entry/32290

“Runaway climate change or runaway global warming is hypothesized to follow a tipping point in the climate system, after accumulated climate change initiates a reinforcing positive feedback. This rapid acceleration in climate change may lead to potentially irreversible damage to the climate system, making timely mitigation efforts unfeasible. This is thought to cause the climate to rapidly change until it reaches a new stable condition. These phrases may be used with reference to concerns about rapid global warming.”

The situation humanity faces with runaway climate change looks like this:

  1. Right now, we (humanity) feel like we are in a period of “predictable climate change.”
  2. During this period, as human beings add more and more carbon dioxide to the atmosphere, we feel like the planet gets warmer in a predictable way.
  3. During this period, we can console ourselves by thinking comforting thoughts like, “If humanity would just stop burning fossil fuels, the additional warming will stop, and things will get better.”
  4. In other words, we still feel like we have control over the future of climate change.
  5. But in the worst-case scenario of runaway climate change, we lose control of our future, and the planet starts heating up on its own.

Increasing carbon dioxide in the atmosphere

What would #5 look like? And how would we detect that it has started? Take a look at this article:

Greenhouse gases continued to increase rapidly in 2022 – https://www.noaa.gov/news-release/greenhouse-gases-continued-to-increase-rapidly-in-2022

It contains this graph of the carbon dioxide concentration in the atmosphere:


NOAA graphic

This looks pretty steady. Humans are adding 37 gigatons of carbon dioxide per year to the atmosphere. In response, the concentration of carbon dioxide in the atmosphere is going up fairly evenly. This graph seems rational and predictable.

What if one day we looked at this graph and it stopped being predictable like this? What if carbon dioxide started going up more than we would expect based on human emissions? Then this would mean that the planet itself has started injecting significant amounts of carbon dioxide into the atmosphere, independent of fossil fuel emissions. Once this process gets rolling in a serious way, things could get ugly very quickly. We would likely enter a period of runaway climate change. The collapse of civilization would be nigh upon us because global heating will increase rapidly.

Where might this extra carbon dioxide come from? One possible source is the thawing tundra in the Arctic circle, as described in this video: https://www.youtube.com/watch?v=QK3QlxD8C-g

The video points out that the defrosting tundra is now releasing 1.7 gigatons of carbon dioxide per year. This number is fairly small (only 5%) compared to human emissions. As more tundra melts, this number will increase. Eventually, tundra emissions will start to approach the level of human emissions, and that’s when they start showing up on the graph above in the form of exponential growth.

What about the methane concentration in the atmosphere?

Now go back to this article again and look at the second graph:

NOAA graphic

Greenhouse gases continued to increase rapidly in 2022 – https://www.noaa.gov/news-release/greenhouse-gases-continued-to-increase-rapidly-in-2022

This is the graph for methane in the atmosphere. Methane is another greenhouse gas. Methane is not as significant as carbon dioxide right now, because there is not as much of it in the atmosphere. Where carbon dioxide is at about 420 parts per million, methane is “only” 1.9 parts per million.

But look carefully at this graph. Methane concentration increased until about 1998, then it leveled off for a decade, and then it started increasing again. After 2020, the amount it is increasing is increasing. This should be a big cause for concern, because this could be the start of exponential growth. If this trend continues, then once again the collapse of civilization is nigh upon us.

What is the difference between methane and carbon dioxide?

Carbon dioxide and methane are both greenhouse gases. In terms of its greenhouse effect, methane is different from carbon dioxide in two ways:

  1. Methane is about 28 times more “powerful” than carbon dioxide as a greenhouse gas.
  2. Methane “expires.” In other words, methane molecules decompose after about a decade, unlike carbon dioxide molecules

Why do we compare methane to carbon dioxide over a 100-year timeframe? https://climate.mit.edu/ask-mit/why-do-we-compare-methane-carbon-dioxide-over-100-year-timeframe-are-we-underrating

“Let’s say a factory releases a ton of methane and a ton of CO2 into the atmosphere today. The methane immediately begins to trap a lot of heat—at least 100 times as much as the CO2. But the methane starts to break down and leave the atmosphere relatively quickly. As more time goes by, and as more of that original ton of methane disappears, the steady warming effect of the CO2 slowly closes the gap. Over 20 years, the methane would trap about 80 times as much heat as the CO2. Over 100 years, that original ton of methane would trap about 28 times as much heat as the ton of CO2.”

In other words, the “mere” 1.9 PPM of methane in the atmosphere compares to about 50 PPM of carbon dioxide. We can understand that if methane increases rapidly, planet Earth will have more and more of a global heating problem.

Therefore, on the methane graph, what if nature starts pumping methane rapidly into the atmosphere independent of human activities? Then humanity has a real problem. Where might this new methane come from? Once again, a warming Arctic Circle creates concern, as described in this video: https://www.youtube.com/watch?v=6Z6RIQ0Bw-E

A hair-on-fire emergency

If humanity were a rational species, we would see the thawing Arctic circle as a hair-on-fire emergency. Both the carbon dioxide and methane frozen in the permafrost would be seen as an existential threat if the permafrost thaws. We would be doing everything humanly possible to prevent the Arctic Circle from warming and thawing, because we are on the verge of causing runaway climate change that will destroy the ecosystem. This video shows one important aspect of the problem – thinning sea ice in the Arctic Ocean: https://www.youtube.com/watch?v=hlVXOC6a3ME

If humanity were rational, what would humanity be doing to stop this hair-on-fire emergency? Here are 6 possibilities:

  1. Obviously we would stop burning fossil fuels. This would stop adding carbon dioxide to the atmosphere and it would help stabilize things.
  2. We would ban cattle worldwide. Cattle produce a surprising amount of methane. See this article for details – https://wraltechwire.com/2022/06/03/doomsday-climate-change-and-cattle-the-case-for-banning-beef-worldwide/
  3. We would ban gas stoves and other gas appliances worldwide. See this article for details – https://www.npr.org/2022/01/27/1075874473/gas-stoves-climate-change-leak-methane
  4. It has been suggested that dyeing the arctic Ocean bright yellow would cut down on the sunlight the water absorbs and cool down the Arctic Circle. This is a fairly massive geoengineering project – dyeing a whole ocean yellow is no small task. We would figure out how to do it.
  5. We would commence other geoengineering techniques to cool down the planet – https://wraltechwire.com/2022/05/27/geoengineering-could-be-key-to-combating-climate-change-check-out-these-ideas/
  6. We would start extracting excess carbon dioxide out of the atmosphere and sequestering it.

Unfortunately, humanity instead seems to be sleepwalking toward the collapse of civilization. At our current pace, humanity is likely to do none of these things. And thus, we will get to witness the collapse of civilization.

Go back to this article again:

Greenhouse gases continued to increase rapidly in 2022 – https://www.noaa.gov/news-release/greenhouse-gases-continued-to-increase-rapidly-in-2022

Watch the three graphs in this article over the next couple of years. If these graphs start to go exponential, the end is nigh.