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(FILES)-- This file photo taken on February 12, 2015 shows emus, an Australian flightless bird, looking for food in the dry earth near the Australian agricultural town of Walgett, 650 kilometres northwest of Sydney. Australia is set to experience more heatwaves, with record-breaking hot weather becoming "normal" across the continent as climate change pushes up land and sea temperatures, a government report warned on October 27. - / AFP / PETER PARKS Image Credit: AFP

World leaders have started to generate some real optimism with their efforts to address global climate change. What’s troubling, though, is how far we remain from getting carbon emissions under control — and how much wishful thinking is still required to believe we can do so.

The Paris agreement on climate change has garnered the national signatories needed to go into force on November 4. Some economists see it as a promising framework for cooperation among many different countries, especially if those not pulling their weight suffer penalties such as trade sanctions. There’s even talk of aiming for the more ambitious goal of keeping global temperatures within 1.5 degrees Celsius or less of their pre-industrial level, as opposed to the currently agreed 2 degrees.

Meanwhile, another major international deal has been reached to phase out greenhouse gases used in refrigeration systems, and solar energy technology continues its rapid advance.

For all the progress, though, the gap between what needs to happen and what is happening remains large. Worse, it’s growing.

Consider, for example, how far the planet remains from any of the carbon emission trajectories in which — according to the Intergovernmental Panel on Climate Change (IPCC) — global warming would remain below 2 degrees. Even in the most lenient scenarios, we would have to be cutting net emissions already.

Bizarre step

Yet under the pledges countries have made in the Paris framework, emissions will keep increasing sharply through at least 2030. As climate scientists Kevin Anderson and Glen Peters argue, an element of magical thinking has crept into the IPCC projections. Specifically, they rely heavily on the assumption that new technologies will allow humans to start sucking carbon out of the atmosphere on a grand scale, resulting in large net negative emissions sometime in the second half of this century. This might happen, but we don’t know how to do it yet.

The assumptions about negative emissions amount to a bizarre step in what ought to be a cautious and conservative analysis.

The IPCC scenarios essentially ignore the vast uncertainty surrounding a technology that does not yet exist, and about our ability to ramp it up to the required scale.

To eliminate that much atmospheric carbon, as geophysicist Andrew Skuce estimates, we would need an industry roughly three times as big as the entire current fossil fuel industry - and we would need to create it fast, building something like one new large plant to capture and store carbon every day for the next 70 years. Does that sound likely?

Perhaps such wishful thinking is an inevitable symptom of our addiction to fossil fuels — and our fear of the wrenching pain that moving away from them will entail. In reality, if we’re not feeling the change, we’re probably not doing enough.

— Bloomberg

Mark Buchanan, a physicist and science writer, is the author of the book Forecast: What Physics, Meteorology and the Natural Sciences Can Teach Us About Economics.