Climate Risk

Judith Curry’s book Climate Uncertainty and Risk aims to provide a framework for understanding the climate change ‘debate’. She argues that the climate change problem and its solution have been oversimplified; that understanding uncertainty can help in better assessing the risks; and that uncertainty and disagreement can be part of the decision-making process.

It is worth stating upfront that Ms Curry agrees that average global temperatures have increased since 1860, that carbon dioxide (CO₂) acts to warm the planet, and that humans have been adding CO₂ to the atmosphere by burning fossil fuels. But beyond that she is uncertain what combination of human-caused vs natural climate variability have been the cause of recent warming and the implications that stem from that uncertainty. She quite rightly rues the polarization of the climate change ‘debate’.

First the positives: Curry’s emphasis on adaptation action on local and regional scales is appropriate and well presented. She rightly points out that “people are helped in the near term as well as in the future by locally designed and implemented adaptation measures to address real vulnerabilities”. She points out that most regions of the world including the United States are not well adapted to even the current range of weather events. Her case studies using simple historical records in conjunction with the IPCC forecasts (ironic given the substantial time she spends undermining them) are a model of common sense.

Curry’s discussion on risk and uncertainty are useful. They highlight that to-date much of the responses to the climate change threat are based on methodologies appropriate to solving a simple problem, rather the complex, multi-layer, non-linear problem that climate change truly represents. The benefits of an adaptive planning approach are well made.

Thirdly, Curry identifies the potential benefits of a campaign to reduce methane emissions and other short-lived climate pollutants. Methane is 25 times more powerful as a greenhouse gas than CO₂, but has a shorter life in the atmosphere (12 years vs 100+ for CO₂). By containing methane emissions, a reduction in global temperatures (estimated at up to 0.3^oC) can be achieved in decadal time frames.

I imagine there would be widespread support for such a campaign and I’m surprised that Ms Curry does not advocate this initiative more widely in her social media presence¹, especially with recent reports showing the exponential growth of methane emissions. A successful methane campaign would also provide many learnings for reducing CO₂ and other emissions. Learning lessons in the transition is an important element of Curry’s proposed approach.

There are however notable weaknesses in Curry’s thesis.

The most fundamental weakness relates to the uncertain or narrow assumptions that support her conclusions. First, she makes the case that there may be near-term cooling due to upcoming natural cycles. While she acknowledges that these same cycles will turn to warming in the second half of the century, it seems she uses this temporary ‘cooling’ prediction to partly justify relaxing the time horizon for reducing CO₂ emissions. This ignores the decades long chunk of extra CO₂ emitted during this delay which will contribute to warming well into the 22^nd century.

She creates a Catch-22 arguing that IPCC’s median model forecasts are the only plausible ones, yet she advocates for pushing out CO₂ emission targets which then raises the risk that the median forecasts are exceeded.

Curry pins her hopes on technological breakthroughs in the next few decades that will deal with the CO₂ and warming problem. She then assumes that a broad consensus for action will suddenly materialize after her ‘not urgent’ delay, which seems implausible.

But there’s an even higher level assumption in Curry’s conclusions. And that is that humankind will be able to adapt and thrive even under significant temperature increases because the increases will happen gradually. She provides no solid basis to support this assumption. If this adaptation is reliant on future technological or geoengineering fixes then it is hardly a ‘resilient’ and ‘anti-fragile’ means of survival.

This complacency about adaptation and ‘thriving’ amid increased temperatures has its roots in climate economics.  Curry references climate economist Richard Tol and his complaints about the IPCC process. Yet this is the same Richard Tol, and his mentor William Nordhaus, that have distorted the climate economics used by the IPCC to significantly underestimate the economic damage that climate change threatens.

Finally, we have all experienced that feeling when we’ve read a news article on a topic we are intimately familiar with and found it riddled with errors. It makes you doubt the credibility of all the other stories from that source. That was my reaction to Curry’s mischaracterisation of the Melbourne desalination project as a case study in maladaptation².

Nevertheless, something we can all agree on appears in the chapter on the response challenge, where Curry says that “We are certain to be surprised and will make mistakes along the way.” The challenge is whether we will learn from our mistakes or use them to ‘own’ the other side.

Climate Uncertainty and Risk is a book suitable for those readers with a good grasp of climate change and a thorough understanding of the arguments put forward by each of the opposing groups. It provides some new and insightful perspectives.  However, it has fundamental flaws. For that reason, I do not recommend it for the average reader with a basic understanding of climate change nor for those just starting their journey.

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Main Image Credit: Arek Socha via Pixabay

Footnotes:

1. As a casual observer of Ms Curry’s social media presence, I notice it is dominated by articles and comments that tend to undermine ‘conventional wisdom’. Doing so fits with Ms Curry’s thesis regarding climate uncertainty, but it’s almost as if perpetuating the uncertainty is her primary objective rather than resolving it. In doing so, Ms Curry has become a darling of those hard-core deniers who generally have little interest in understanding the science and its uncertainty and more in ‘angertainment’ and moral outrage. Curry’s current social media approach is probably more effective in obtaining followers and clicks than taking a more positive stance, and has the effect of adding to polarization rather than reducing it. It would be welcome if Ms Curry would spend more time advocating for her transition plan elements including a campaign to reduce methane emissions, and making those the dominant focus of discussion.
2. As a Melburnian and also someone with an intimate knowledge of the Melbourne Desalination Project, I can say that the characterization of the project in the book as maladaptation is just plain wrong: For a start, there was no ‘significant’, ‘vehement’ indigenous push back regarding the plant site. On adapting to a low water environment, the previous decade saw a sustained campaign to reduce Melbourne’s per capita water usage. This was highly successful. Twelve years after the desalination plant, residential water usage in Melbourne averages 159L per person and there is high water awareness amongst Melburnians, with a current campaign to reach 150L, which is important given the rapid growth of the city. (For comparison, the San Francisco Bay Area, at a mirrored northern latitude, has an average residential water usage per capita of 236L. Los Angeles – over 400L). On energy usage, the plant is 100%-powered by certified renewable energy drawn mainly from a purpose-built wind farm. Over the subsequent ten years the amount of wind generation capacity in the state has increased eight-fold. As the city grows beyond 4 million, planning is underway to add further desalination or other rainfall-independent water sources to the water supply. It’s hard for Curry to argue for increased resilience on the one hand, and then consider Melbourne’s desalination and demand reduction campaigns a maladaptation.