Childhood’s End

The Future of Humanity, Part 4

Photo by Sergio Casillas on Unsplash.

This is Part 4 of my 7-part series on the future of humanity. The series starts here.

“Elements of modern human civilization — our cities, agricultural practices, fossil fuel dependence — have not withstood the test of time, nor can they.” — Tom Murphy, Energy and Human Ambitions on a Finite Planet, p. 406.

Anticipating a 2–4°C warmer world

It’s time to look more closely at how an energy transition in a 2–4°C warmer world is likely to play out. It’s not a pretty picture. In fact, we end up learning rather quickly that all the dire warnings we have been hearing from the IPCC and others about possible catastrophic effects of climate change are probably underestimations because they are based on models that do not include many of the second-order “unknowns” that might emerge in a hotter world: potential interaction effects (effect A and effect B occur simultaneously and exacerbate each other), cascading effects (A triggers B, which triggers C, etc.), and tipping points (A reaches a level that produces an irreversible and extremely hazardous effect).

It is instructive and perhaps revealing that while governments and politicians continue to sing the tune of a 1.5°C warmer world, climate scientists are becoming more concerned about the need to better understand the potential impacts and consequences of more extreme temperature outcomes. As one team noted in a paper released this year:

“As noted by the Intergovernmental Panel on Climate Change (IPCC), there have been few quantitative estimates of global aggregate impacts from warming of 3 °C or above (source). Text mining of IPCC reports similarly found that coverage of temperature rises of 3°C or higher is underrepresented relative to their likelihood (source).”

The authors note a spate of recent research that appears to leave the 1.5° goal in the dust, including a recent “gold standard” study we reviewed in Part 2:

“Recent findings on equilibrium climate sensitivity (ECS) (source, source) underline that the magnitude of climate change is uncertain even if we knew future GHG [greenhouse gas] concentrations. According to the IPCC, our best estimate for ECS is a 3 °C temperature rise per doubling of CO2…