CLIMATE CHALLENGESDelay and Pay: Tipping Point Costs Quadruple After Waiting
There’s more to weigh than catastrophic environmental change as tipping points draw near. Another point to consider, a new study reveals, is the cost of undoing the damage.
Tip the first tile in a line of dominoes and you’ll set off a chain reaction, one tile falling after another. Cross a tipping point in the climate system and, similarly, you might spark a cascading set of consequences like hastened warming, rising sea levels and increasingly extreme weather.
It turns out there’s more to weigh than catastrophic environmental change as tipping points draw near, though. Another point to consider, a new study led by researchers at the Department of Energy’s Pacific Northwest National Laboratory reveals, is the cost of undoing the damage.
The cost of reversing the effects of climate change—restoring melted polar sea ice, for example—quickly climbs nearly fourfold soon after a tipping point is crossed, according to new work published today in the journal npj Climate and Atmospheric Science. Much work has been done to explore the environmental costs tied to climate change. But this new study marks the first time researchers have quantified the costs of controlling tipping points before and after they unfold.
Common examples of Earth’s tipping points include melting ice sheets and dwindling tropical coral reefs. As ice melts and reefs die off, drastic environmental effects like flooded coastal cities and lost biodiversity soon follow—a shared trait among what the Intergovernmental Panel on Climate Change defines as “critical thresholds in a system that, when exceeded, can lead to a significant change in the state of the system.”
Despite the well-established dangers of crossing a tipping point, little is known about the cost of controlling them. How much effort would it take to stop and reverse course just before crossing a tipping point?
In the case of polar sea ice, which is melting at a pace unrivaled by any period in the past 1,500 years, a reversal would entail halting melt and reestablishing ice cover. But how about after we tip—how might the cost of intervention change if we wait?
Cross a tipping point threshold, said mathematician and lead author Parvathi Kooloth, and it costs nearly four times the effort to reverse the effects and reestablish the climate system to where it was just before tipping, as opposed to reversing course before the threshold. The message applies to most tipping points, said Kooloth, whether they involve tropical coral reefs or frigid sea ice.
