Scientists on the Intergovernmental Panel on Climate Change, a global group backed by the United Nations, have spent the past two weeks in meetings to ready their latest assessment of the physical science underpinning past, present, and future climate change. Expect the IPCC to paint a sobering picture of what is to come. The steep costs of such a world are all too apparent, but tallying them is harder still.
That latter bit is the bread and butter of climate economics: accounting for climate damages in dollars and cents. The Holy Grail is translating those numbers into how much each ton of CO₂ costs society and, thus, should cost those doing the polluting. It’s important but thankless—more like boring accounting than cutting-edge economics.