Bret Kugelmass

Opinion contributor

As a technology entrepreneur, when I am approached by startup founders for fundraising advice, I ask: “What would the world look like if you got everything you're asking for?” It’s a test to see whether they are setting out to solve the right problem or whether they are choosing their preferred course of action and justifying retrospectively.

Climate change researchers fail this test. Every single time.

A giant disconnect exists between the science branch and policy branch of the climate change community, obscured by a strong tribal bond that unites us against "deniers." But if climate advocates get what we say we want, our own hypocrisy would soon be made painfully apparent.

The accepted policy rhetoric is that if we get to net-zero global emissions, we would "solve" climate change — when, in fact, this belies scientific reality.

Achieving 'net zero' isn't enough

Let’s explain why. The term net-zero means that every ton of greenhouse gas that is currently emitted (more than 37 metric billion tons yearly) will be either eliminated outright or offset. That’s a lot of fuel — heating homes, moving goods, powering industry — that needs to be replaced. Although certainly difficult, it's not impossible. But what then? Does the temperature stop rising? Think again.

It is the extra greenhouse gases we have accumulated over the past two centuries— approximately 1 trillion tons — that ratchet up the temperature year over year and will continue to do so regardless of future emissions. These gases do not​ ​act like a sponge, having already soaked up extra heat from the sun. Rather, they act as a valve, controlling the rate at which additional heat is accumulated.

Even if we were able to flip a switch tomorrow and magically achieve net-zero new emissions globally, we’d nevertheless continue to add extra heat.

This is what scientists call “radiative forcing." At this point, allowing for natural biological processes to restore the atmosphere to a state of radiative balance​ ​would take thousands if not tens of thousands of years. We’ve burned a lot of hydrocarbons.

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Net-zero will result in severe climate change; we require extreme levels of negative emissions.

So, are we doomed? Not at all.

Given this constraint, our climate change problem actually becomes much more straightforward to solve, but it limits the solution set drastically. This is an affront to the coalition of “all of the above” and deprives many of the strongest climate advocates their favorite solutions. Trying to refute this reality is where the "science side" engages in denial, too.

We must remove greenhouse gases

Let’s work this out logically:

To stop temperature rise, greenhouse gas concentrations need to be restored to a level where temperatures will remain constant, meaning about a trillion tons of carbon dioxide need to be removed from the air.

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Natural, biological methods of greenhouse gas removal can only work so fast — maybe a few billion tons a year — so it will take technological processes to achieve thermal balance in a meaningful time frame.

These technological processes all require energy, a lot of energy. Consider how much energy it takes to move a ton of anything, then think about a trillion tons of carbon dioxide. And, because dioxide is very dilute, we also must move quadrillions of tons of the gas it is mixed with and then chemically process a trillion tons on top of that.

Every energy source has a carbon footprint. Even renewables require energy and chemicals to move and transform raw materials into energy production systems. (To make solar panels, burning coal is necessary to transform silicon dioxide into the requisite purified silicon.)

Here’s the crux: Since it takes energy to remove carbon and carbon is released in making energy, being "low-carbon" isn’t good enough! The energy source used needs to have such an extremely low carbon footprint that it can effectively power the capture and transformation of carbon dioxide.

Regardless of cost and considering only the carbon math, the only possible energy source capable of powering atmospheric carbon dioxide removal — true negative emissions — is nuclear energy.

This becomes obvious considering that any power source’s carbon footprint is a function of materials required to produce this energy. Using nuclear forces (the energy inside an atom), instead of chemical forces (the energy between atoms), we produce 3 million times as much power for the same amount of material.

There’s still plenty of room for debate over values, adaptation, speed of change and robustness of scientific models. But when one side can’t imagine how the other side can be so wrong, it’s important to remember: Everyone ignores the science when it doesn’t support their values.

Bret Kugelmass is managing director of the Energy Impact Center, a Washington, D.C.-based research institute.