11. A WORD ON MODELS
Essentially, all models are wrong, but some are useful.
- George Box
At one point in my life, I used to be really into modelling. Not tiny plastic airplanes or people who show off clothes, but representations of real life that can help visualize things it’s not practical to observe. Before a mission in Afghanistan for example, we’d sometimes build these very simple models out of pieces of rope or tape laid out on the ground to create a building floor plan, which helped us think about how to attack difficult compounds because they’d give us a better sense of what to expect. Ultimately, we used models to anticipate what we were getting into and how our plans might need to change.
Models that predict what the earth will look like under rising temperatures do kind of the same thing; they use climate physics and factors like atmospheric water vapor content, air pressure, temperature, wind, and, of course, emissions of greenhouse gases1 to help anticipate how bad things might get and, more importantly, how urgently we need to get involved.
The thing to remember when it comes to how bad climate change might get is that the predictions are only as good as the available data and the models used. Both of these factors could, in theory, be sources of error. Assuming the data is not made up by villainous scientists pushing a conspiracy to secure more funding, what are the chances that the models used to make climate predictions are wrong?
Unlike conspiracy theories, chances that the predictions are off are much better than zero because models are inherently flawed. They cannot include all the details of complex systems. Instead, they are approximations, like how our fake floor plans weren’t 3D representations. Since the earth is one of the most complex systems we know, it makes sense that modelling it would be difficult, so criticizing predictions based on the accuracy of the models is totally appropriate. For example, the response of oceans to climate change is uncertain because there’s no accepted theory for how heat circulates in ocean depths, which could potentially create big variability in future projections2.
Keep in mind though, that while climate models may be flawed, they may still be useful.
To find out how useful, climate models must be tested. Scientists have done this, because it’s a no-brainer. A 2019 evaluation of 17 different models developed over a 37-year period found that 14 of the models had projections that closely matched observed temperature changes3. Even models that were developed in the 1970s were incredibly accurate. That’s both good and bad news. The good news is that the models are generally working. The bad news is that they’re telling us that the effects of climate change are going to get worse, which means the time to get involved is now.
Of course, there will be people who claim the models are spitting out the wrong results. In their defence, that same 2019 evaluation study showed that a few models did indeed forecast too much warming, so it’s at least possible the others could have errors too.
There’s also a possibility, albeit a small one based on current research, that climate change isn’t the buzzkill most scientists make it out to be. Plants use CO2 to grow, so in theory, higher emissions mean more CO2 in the atmosphere, which means plants should grow better. Plus, a greater number of warmer days means a longer growing season4. Again, in theory, those two things could equal higher agricultural yields, or even more food. Also, less people will die from cold-related temperatures5, and the economies of countries like Canada, Norway, or Russia might even get much-needed boosts6.
So…climate change could be a good thing?
Well, maybe, in some cases. But mostly no.
Climate change is complex, and it’s likely to bring a few, localized positives. Countries in northern latitudes, like Finland for example, might have longer growing seasons with warmer temperatures7. That doesn’t mean the negatives of climate change won’t happen; they will. The question then becomes, do the benefits outweigh the positives?
The answer to that question depends on where you live, but is almost certainly a resounding no. While countries in cooler latitudes might benefit from economic growth, they will also see many of the negative effects, such as more extreme weather, species loss, and sea level rise. Meanwhile, hotter temperatures in warmer countries will lead to decreased productivity, and increased country to country inequality8, which is never a good thing. So even though there may be some localized benefits, on the whole, climate change is expected to be a very bad thing for the world.
It’s also important to remember that modelling errors can work both ways. While it’s true the available models might be overestimating the effects of climate change, it’s also possible the predictions are underestimating what’s going to happen. In that case, then the time to get involved by serving others isn’t now, it was yesterday, which is what the youth-led nonprofit Climate Cardinals had in mind when they came together to spread awareness about climate change by translating climate information for those who don’t speak English9.
In the end and based on accuracy so far, pinning the Earth’s future on current climate models being wrong is akin to hope, which reminds me of a military saying we’d use when considering different ways to crack difficult scenarios on operations. It goes like this:
“Hope is not a course of action.”
In other words, if our plan relies on us getting a bunch of lucky breaks, it’s not a very good plan because it’s not something we control. Planning for climate models to be wrong – when most available data is telling us they’re quite accurate and getting better - is essentially doing just that, relying on hope as a course of action. As things stand right now, climate change is most certainly not going to fix itself, which means that we have to get involved.
MIT Climate Portal, Climate Models: Explainer, January 8, 2021, Climate Models | MIT Climate Portal, accessed May 6, 2022.
MIT, Climate Primer: Chapter 06, Predicting Climate, Climate Science, Risk & Solutions, Climate Change - Climate Science, Risk & Solutions (mit.edu), accessed May 5, 2022.
Zeke Hausfather, Henri F. Drake, Tristan Abbott, and Gavin A. Schmidt, “Evaluating the performance of past climate model projections,” Geophysical Research Letters, vol. 47 (1), 16 January 2020, https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL085378, accessed 2 Jun 23.
Dayaratna, K.D., McKitrick, R. & Michaels, P.J. Climate sensitivity, agricultural productivity and the social cost of carbon in FUND. Environ Econ Policy Stud 22, 433–448 (2020), https://link.springer.com/article/10.1007/s10018-020-00263-w#, accessed 2 Jun 2023.
Benson, T. “Research & Commentary: Heartland Brief Details Minimal Impact, and Positive Benefits, of Climate Change in Montana,” The Heartland Institute, November 21, 2019, https://www.heartland.org/publications-resources/publications/research--commentary-heartland-brief-details-minimal-impact-and-positive-benefits-of-climate-change-in-montana, accessed 2 Jun 2023.
Diffenbaugh, N.S., and Burke, M. “Global warming has increased global economic inequality,” PNAS, March 22, 2019, https://www.pnas.org/content/pnas/116/20/9808.full.pdf, accessed 9 Mar 2020.
Burke, M. Hsiang, S.M., and Miguel, E. “Global non-linear effect of temperature on economic production,” Nature , https://www.nature.com/articles/nature15725. Accessed 9 Mar 2020.
Diffenbaugh and Burke, “Global warming has increased global economic inequality,” accessed 9 Mar 2020.
Climate Cardinals, About, https://www.climatecardinals.org/about, accessed November 16, 2021.