It’s getting hotter out there.

I’m not talking about the weather, although here in California and much of the American West we’ve been alternately sweltering and scanning the horizon for whiffs of wildfire.

I’m talking about the heat being turned up under companies making net-zero commitments.

Yes, the businesses that have set those goals are coming under special scrutiny, never mind that only about 20 percent of the world’s 2,000 largest corporations have yet done so, according to the University of Oxford. The other 80 percent seem to be getting a free pass, at least for the moment. It’s the so-called leaders that are taking the heat.

You can’t say we didn’t see it coming.

The problem? "Net zero," for all of its compelling simplicity, turns out to be anything but. Indeed, it is fraught with problems, and companies — the leaders and the wannabes alike — are finding themselves encountering a crescendo of criticism.

Net zero, for all of its compelling simplicity, turns out to be anything but.

That criticism is coming from activists, of course, but also from scientists and policymakers, who are beginning to see the misdirection of some net-zero commitments. As you’d imagine, firms in the fossil-fuel sector are squarely in the bullseye, but so are those in other sectors: retail, technology, finance, food and ag, mining, transportation and more.

Given the lack of policy or standardized guidance driving net-zero commitments, not to mention the loopholes through which many companies seem to be leaping, there’s pretty much a net-zero chance that they will, collectively, meet the goals of the 2015 Paris Agreement — at least, not without some significant changes.

Snared in the ‘net’

To understand the problems, I highly commend two recent treatises. The first is a must-read essay by Jonathan Foley, executive director of Project Drawdown, a nonprofit research and advocacy group focusing on climate solutions.

The second is a report published earlier this month by Corporate Accountability, Global Forest Coalition and Friends of the Earth International — and backed by more than 60 other environmental groups — boldly titled "The Big Con: How Big Polluters are advancing a ‘net zero’ climate agenda to delay, deceive and deny."

You weren’t expecting subtlety here, were you?

Let’s begin with Foley, an award-winning scientist and communicator who has published more than 130 peer-reviewed scientific articles. He notes that the term "net zero" originally was used by climate scientists "to describe scenarios when the entire atmosphere was, on balance, no longer building up greenhouse gases. Not a company or a country. The whole planet." A world where emissions reductions reign over offsets, and where "carbon removal projects are only used for a few remaining emissions."

"A lot of companies have made dubious climate commitments using accounting tricks — usually relying on problematic ‘carbon offsets’ to make the books look better than they are," Foley writes.

Among the problems, he says, are that the nature-based solutions being widely touted as a means of offsetting carbon emissions are of dubious efficacy. These offsets, "which bank on trees, farms, oceans and machines to remove greenhouse gases from the atmosphere, make a very risky bet." Yes, they can absorb some atmospheric carbon, he says, "but only to a point."

Carbon-removal strategies, for their part, "are laughably small compared to the job at hand. Even a millionfold scale-up of carbon removal technology would only absorb a tiny percentage of our emissions," Foley writes. "... We need to see that vague promises of future carbon removal are just sneaky ways of allowing emissions to continue unchecked today."

There’s also the time horizons of net-zero commitments: far-off goals with few, if any, interim milestones. Not least the fact that nearly all net-zero commitments focus only on future emissions, not historical ones. As Foley put it:

[I]f a factory was dumping toxic sludge into a local lake, government agencies would order it to do two things — stop polluting the lake as quickly as possible and then clean up the pollution it already dumped there. Why is the atmosphere any different?

Foley’s piece will set you up nicely for "The Big Con," the activist report, which covers similar ground, except in harsher terms. One choice passage:

The idea behind big polluters' use of "net zero" is that an entity can continue to pollute as usual — or even increase its emissions — and seek to compensate for those emissions in a number of ways. Emissions are nothing more than a math equation in these plans; they can be added [to] one place and subtracted from another place.

This equation is simple in theory but deeply flawed in reality. These schemes are being used to mask inaction, foist the burden of emissions cuts and pollution avoidance on historically exploited communities, and bet our collective future through ensuring long-term, destructive impact on land and forests, oceans and through advancing geoengineering technologies. These technologies are hugely risky, do not exist at the scale supposedly needed and are likely to cause enormous, and likely irreversible, damage.

The report dismantles many solutions to which companies are increasingly turning to meet their net-zero commitments, among them: bioenergy ("burning trees emits more greenhouse gas emissions than coal or natural gas, when taking into account the lifecycle of the emissions and when implemented at commercial scale"); carbon markets ("proven to lead to fraud and speculation, and haven’t substantially reduced emissions"); nature-based solutions ("many of these schemes have been widely discredited and shown to not only fail to offset the emissions in question or only do so temporarily"); and carbon offsets ("often displace communities, claiming to reduce deforestation that is usually insignificant, not permanent or verifiable").

‘Blank cheque’

Of course, not everything is as black and white (or green and brown) as the report suggests. And certainly not all of these efforts are worthless. For example, high-quality offsets, verified to one of the globally recognized standards, can play a key role in sequestering greenhouse gases for decades, as can restoring mangrove swamps and several other regenerative, nature-based solutions. (Project Drawdown has done the math on this.) Like many activist-written reports, this one takes a breathless and wholesale approach, tarring all companies with the same brush without differentiating between leaders and others.

These are hardly the first such criticisms of net zero, but the volume seems to be growing in lockstep with the corporate commitments themselves.

Still, "The Big Con" is worth a read, as it takes a fairly substantive swing at companies’ commitments, pointing out many of the same flaws — the lack of interim targets, the omission of Scope 3 (supply-chain) emissions, the reliance on unproven technological fixes — that Foley describes. More than a score of companies are called out by name in the report.

These are hardly the first such criticisms of net zero, but the volume seems to be growing in lockstep with the corporate commitments themselves. Back in April, for example, Robert Watson, a former chair of the Intergovernmental Panel on Climate Change, and two co-authors called net zero a "dangerous trap" set by companies and governments to assuage global climate concerns. They called such commitments "a blank cheque for the continued burning of fossil fuels and the acceleration of habitat destruction."

That "blank cheque" will likely become a growing meme in the coming months.

It’s not too late — and certainly not too early — to make adjustments, lest "net zero" becomes synonymous with "greenwash." The concerns and criticisms will only get louder. A reckoning is coming, and quickly.

Don’t get me wrong. There’s game-changing potential in net zero. At minimum, it’s a compelling concept: Nothing is clearer or more definitive than zero, at least theoretically. It is, conceptually speaking, a worthy destination. Undertaken with sound science and planetary intentions, net zero represents the only path forward to addressing the climate crisis.

But we’re at a critical juncture. If companies fail to heed the warnings — not to mention the science — net zero will be in for a fall. Whether it takes down companies — and humanity — is destined to become the story of the century.

I invite you to follow me on Twitter, subscribe to my Monday morning newsletter, GreenBuzz, from which this was reprinted, and listen to GreenBiz 350, my weekly podcast, co-hosted with Heather Clancy.