CICERO Report: Climate Modeling Is Hard, But We Are Heading For Disaster

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There is a lot of happy talk from global leaders trying to put a brave face on the COP26 fiasco. Prime Minister Boris Johnson declared after the conference, “[T]he world is undeniably heading in the right direction.” John Kerry, the special climate envoy for the United States added, “We are in fact closer than we have ever been before to avoiding climate chaos.”

Neither statement is true. The latest study from CICERO, the Center For International Climate Research in Oslo, Norway, makes two points. One, predicting what the Earth’s climate will be like in 10 years from now is immensely difficult. Two, trying to see through a fog of numbers into the middle future — 2100, for instance — is an incredibly daunting task.

Imagine the Earth is a giant billiard table with trillions of balls on it. Trying to calculate what ball number 2,345,675,964 will do in 50 years if you hit ball number one with the cue ball today is impossible. All you can hope for is a range of possibilities and to narrow that range as much as you can.

In its latest study, which is published in the journal Nature Climate Change, the authors argue that the business as usual case will lead to a rise in global temperatures of between 2.3º C and 2.9º C by 2100. Plugging in the numbers based on the pledges made before and during COP26, temperatures are projected to rise 2.2º C to 2.7º C. The range expands to 1.7 to 3.8° C when it includes the uncertainty in the climate response. At the upper end of that range, global average temperatures will be high enough to wreak unimaginable destruction on the environment and humanity.

If people were told we were about to explode 10,000 nuclear bombs all around the world, they would be rushing around in a panic — weeping, screaming, and tearing their clothes. But tell them warmer average temperatures will have a similar effect and they shrug. “Oh, well,” they say. “What can you do? Is it time for Jeopardy yet?” Here is the abstract for the new study:

“Most of the integrated assessment modelling literature focuses on cost-effective pathways towards given temperature goals. Conversely, using seven diverse integrated assessment models, we project global energy CO2 emissions trajectories on the basis of near-term mitigation efforts and two assumptions on how these efforts continue post-2030.

“Despite finding a wide range of emissions by 2050, nearly all the scenarios have median warming of less than 3 °C in 2100. However, the most optimistic scenario is still insufficient to limit global warming to 2 °C. We furthermore highlight key modelling choices inherent to projecting where emissions are headed.

“First, emissions are more sensitive to the choice of integrated assessment model than to the assumed mitigation effort, highlighting the importance of heterogeneous model intercomparisons. Differences across models reflect diversity in baseline assumptions and impacts of near-term mitigation efforts.

“Second, the common practice of using economy-wide carbon prices to represent policy exaggerates carbon capture and storage use compared with explicitly modelling policies.”

That last paragraph puts us on notice that all the talk of carbon capture by the fossil fuel companies is a steaming load of horse-puckey. In today’s email from Bloomberg Green, author Akshat Rathi says, “The lower end of Cicero’s forecast would put the world very close to the most ambitious goal under the Paris Agreement to keep global temperature rise below 1.5° C. That would result in many more extreme weather events than we face currently at 1.1°C of warming, but it’s likely to avoid triggering some irreversible changes such as the collapse of the West Antarctic ice sheet.

“The upper end of the forecast would see the world blow past the less ambitious Paris goal of limiting warming to 2°C. A planet that’s nearly 4°C hotter would make vast parts of Earth uninhabitable, triggering mass migration of hundreds of millions of people and throwing the global economy into a tailspin.”

Better Modeling, But Still Dire Consequences

“During COP26 it was confidently communicated that current policies would lead to 2.7° C of warming in 2100 and emission pledges to 2.4° C of warming, while we find that the uncertainties are much greater and that the answer depends on what model is used,” says Ida Sognnaes, lead author of the study.

“Most countries have specified policies or pledges to around 2030, but how the implied effort is extrapolated forward through to 2100 is a fundamental uncertainty,” adds co-author Glen Peters. The study tried to harmonize as many input data and assumptions as possible to isolate the effects of model diversity. Even though it used seven models, the spread between their predictions remained significant.

“The large model spread highlights the important role of tools used to inform climate policies and pledges, and the critical need to employ diversified toolboxes,” says Alexandros Nikas, another co-author. “This study is one of the few to focus on the challenge of extrapolating policies from 2030 to 2100.”

“To date, integrated assessment modelling has overwhelmingly focused on what needs to be done to reach pre-defined temperature targets. Here we instead shine a light on where current efforts are taking us, and it reveals a great deal of uncertainty, depending on the modelling approach,” says co-author Ajay Gambhir. “We could be on a path to just over 2°C, or just under 3°C, with very different climate consequences in each case.”

The large uncertainties indicate that more effort is required to avoid dire global warming outcomes. “The large uncertainties indicate that current policies and policy pledges can still lead to warming outcomes of 3°C in 2100,” says Sognnaes. “The false precision to climate outcomes given during COP 26 may lead countries to believe they are making good progress, when the opposite may indeed be the case.” Peters adds, “Predicting emissions in 2030 is difficult enough but extrapolating to 2100 is heroic and requires a good dose of humility to avoid giving false precision.”

Some Progress, But Not Enough

“To be sure, there’s definitely been progress,” Rathi writes in Bloomberg Green. “Before the Paris accord was signed, the Emissions Gap report from the United Nations projected possible warming to be between 3°C and 7°C by the end of the century.

“Thanks to better climate modeling, cheaper green technologies, and more willingness from governments to reduce emissions, the world is no longer on a path of utter destruction. And yet the worse-case outcome of apocalyptic 4°C warming still remains possible. That means there is little time to rest on the gains made at COP 26.”

The Takeaway

The discussion of rising temperatures is important, but it ignores the social consequences of what is to come. Anthropologists believe that during the last Ice Age that ended about 12,000 years ago, humans in Europe withdrew ahead of the advancing ice sheet and settled near the relatively temperate Mediterranean Sea. As the ice receded, they moved back north again.

Anyone who thinks global heating is not going to lead to similar population shifts is naive. There are bound to be titanic struggles between people who are already settled in areas less affected by floods, famines, and forest fires and those seeking to move there. Armed conflict is inevitable as hatred of “the other” becomes the dominant theme of societies around the world.

Perhaps a nuclear winter will follow, which at least will give the Earth a chance to cool off a bit, even if billions are exterminated in the process. Every cloud has a silver lining.


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Steve Hanley

Steve writes about the interface between technology and sustainability from his home in Florida or anywhere else The Force may lead him. He is proud to be "woke" and doesn't really give a damn why the glass broke. He believes passionately in what Socrates said 3000 years ago: "The secret to change is to focus all of your energy not on fighting the old but on building the new." You can follow him on Substack and LinkedIn but not on Fakebook or any social media platforms controlled by narcissistic yahoos.

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