There’s been a fair bit of buzz about an article in New York Magazine with an apocalyptic picture of climate change over the next century. I’ll for a more complete response later. But as it happens, I was already thinking about a much more optimistic post.

From the Climate Change Authority, of which I was a Member until recently, here’s a set of emissions trajectories consistent with a 67 per cent probability of limiting warming to 2 degrees.



There’s a pretty good case to be made that we are on the blue trajectory, and that, with decent political outcomes, we will be able to go below it and hold warming to the Paris aspirational target of 1.5 degrees. That would still have plenty of negative effects, for example on coral reefs, but it would not be an existential threat to humanity.

The points that are critical in the blue trajectory are a peak in emissions, right about now and a drop to zero net emissions by 2050. The first looks to have been achieved. As for the second, we are already seeing commitments to this goal from developed countries and jurisdictions, and there’s every reason to think it can be achieved at low cost.

As an economist, this is about the outcome I would have expected given a global commitment to an emissions trading scheme with a carbon price on a rising trajectory to $US100/tonne or so. In fact, we’ve seen nothing of the kind. There has been no real global co-ordination, and where carbon prices have been imposed, they have been low and limited in scope.

Instead, we’ve had a series of favorable technological surprises of which the most striking have been the plummeting cost of solar photovoltaics, and advances in battery technology allowing both low-cost electricity storage and affordable electric vehicles. There’s no reason to think these advances have run out, or that any of the remaining problem areas (air transport, cement manufacture and so on) will prove insuperable.

What these developments mean is that carbon-based electricity generation is on the way out, and that the end of the internal combustion engine is in sight, probably well before 2050.

Should this have been a surprise? In one sense, perhaps not. There were a lot of potential technological options out there, and we only needed a couple to work. There were plenty of failures and disappointments (nuclear fission and fusion, carbon capture and storage, biofuels, geothermal) and more limited successes (energy efficiency, solar thermal and wind power) along with the surprise success of PV. The same point may be made in the particular case of storage. Any reversible process involving energy can form the basis of a storage technology, so there is a huge range of possibilities, from flywheels to pumped hydro to batteries based on many different chemical reactions. Viewed that way, it would be a surprise if we couldn’t find a good one.

On the other hand, there’s no obvious technical reason why we couldn’t have developed most of these technologies decades ago. So, it clearly needed a push from policy and public concern to get them to happen. Solar feed-in tariffs of 50c/kwh may look excessive now, but policies like this, in Australia and elsewhere, gave the industry the start it needed. Even without price incentives, the importance of the problem attracted attention from researchers and technologists that might otherwise have been allocated elsewhere.

So, I think we will escape the cataclysm, but more through technological luck than successful policy management.

Final note: This assumes minimal political good sense. That’s not always in evidence, most obviously from the Trump Administration in the US and its Australian allies, but, thankfully, neither of these look set to endure for long.