Among environmentalists, there has long been a suggestion that the transition to net zero has been far too slow. Research from PIK Potsdam suggests they might be right, and that a rapid transition easily pays off.

The researchers have created a new approach to evaluate the significance of decisions in scenarios with highly uncertain outcomes. Using the method on a model greenhouse gas emission issue shows that it is reasonable to choose an early shift to a carbon-free society, even when the chances of realizing it are low.

“We have discovered that it is almost always the case that best decisions are still best, even when the probability that they are actually implemented becomes very, very small,” the researchers explain.

Clean transition

The study employed a validated theory of policy advice that enables the calculation of the “best” policies for problems requiring step-by-step decisions under uncertainty. The policies were then compared with available options at each decision step to determine the importance of avoiding mistakes.

The method was applied to a model greenhouse gas emission issue with dual objectives: avoiding the harmful effects of climate change and minimizing economic harm. The program evaluated the outcomes of two options: immediately transitioning to a green economy or delaying the transition to minimize economic damage.

The results showed that optimal decisions are still valuable, even when the likelihood of implementation is low, due to factors such as political uncertainty or legislative inaction.

“At the first glance this seems surprising, as the common wisdom is that it’s not worth betting on something that is not likely to happen,” the researchers explain.

“But, if you think twice, the result makes sense. It also provides a guideline to the discussion on whether it is worth to pursue climate targets (like the 1.5°C target) that are unlikely to actually be met: the answer is yes.”

“More generally, the paper is a methodological contribution towards understanding which decisions under uncertainty matter most. Realizing that certain decisions are less important than others (or less important than expected) can be very helpful, for example in climate negotiations,” they conclude.