Larsen C and solar geoengineering


Michael Thompson, of the Forum for Climate Engineering Assessment wrote me asking me about my thinking regarding the Larsen Ice Shelf and solar geoengineering. My responses, alongside others, were published on this web page: .

My comments are repeated here:

Ken Caldeira: “Melting in Antarctica is strongly influenced by interactions involving the circulation of seawater, and its interaction with glacial ice, sea ice, surface winds and temperature, sunlight and so on. Many important interactions are occurring on small spatial scales that have not yet been successfully integrated into models simulating large-scale phenomena — and so the influence of various possible solar geoengineering deployments on Antarctic ice sheet dynamics remains largely unknown and unexplored.

The governing hypothesis is that if warming temperatures lead to ice melt, cooler temperatures are likely to help slow or even stop that melt.

It might turn out that it is effectively impossible to cool the water adjacent to ice shelves with solar geoengineering techniques. However, I would be surprised if that turns out to be the case. My expectation is that the primary factors limiting the amount cooling produced by solar geoengineering would be unintended consequences and sociopolitical acceptance.

We should be researching the potential effectiveness and unintended consequences of using solar geoengineering techniques to reduce the amount of damage caused by climate change. However, I would want to know a lot more about potential efficacy and unintended consequences, and understand how the solar geoengineering deployment fits into the broader spectrum of efforts undertaken to avoid climate damage, before I would want to consider using solar geoengineering approaches to protect Antarctica.”



Red team, blue team

Justin Gillis of the New York Times asked me to comment on a proposal by EPA head Scott Pruitt regarding a red-team/blue-team approach to climate science. I wrote this set of possible quotes, and one of them appeared in this article: EPA to Give Dissenters a Voice on Climate, No Matter the Consensus, by Brad Plumer and Coral Davenport.


I would love to hear Scott Pruitt explain how he thinks the scientific process works. What does he think scientists are doing all day? Scientists are already spending most of their time trying to poke holes in what other scientists are saying.

The whole red team / blue team concept misunderstands what science is all about. Scott Pruitt seems to imagine that science today is like a football game with a single team on the field. In fact, science is like having thousands of people out on the field, each playing for themselves, fighting tooth and nail to show that they are right and everyone else is wrong.

We don’t want red team / blue team because science doesn’t line up monolithically for or against specific positions. Science is an ongoing process of thousands of people constantly chipping away at or refining a set of hypotheses.

Scientists in the United States have organized themselves to create the best scientific infrastructure in the world, and now we need a politician to tell scientists how to do science? If Scott Pruitt really wants to improve climate science, he should be fighting for bigger budgets for climate scientists.

Why do politicians who have never engaged in any scientific inquiry in their lives believe themselves to be the experts who should tell scientists how to conduct their business? A little more humility would be appreciated. This is yet another example of politicians engaging in unhelpful meddling in things they know nothing about.

Why is Scott Pruitt trying to ‘fix’ climate science. It is not broken. If Scott Pruitt really wanted to help climate science, he would be fighting to increase budgets for climate science research.

All of science is about one person claiming to have evidence supporting a hypothesis, and then other people trying to show that the first person was either wrong or missing something important.

Science is a constant process of scientists challenging the claims of other scientists.

Some more thoughts (written after the original email to the Times):

Isn’t science all red team? Isn’t all of science aimed at falsifying hypotheses? Popper would say that if you are trying to prove that something is true, then you aren’t doing science.

I just don’t understand which hypotheses Scott Pruitt thinks climate scientists are being insufficiently rigorous about testing. Scott Pruitt should clearly state the hypotheses that he thinks climate scientists are accepting prematurely. 

Will Pruitt commit to vigorous and effective action on emissions reduction if the main findings of climate science are shown to be sound? [Hasn’t the science already been shown to be sound?] Is the Trump Administration committed to basing policy on the best-available scientific information?

unnamed (1)