Net zero CO2 emissions: A damaging and totally unnecessary goal – Roy Spencer explains why

We may not believe CO2 plays a big part in global atmospherics anyway, but even if it somehow does, the full story is not being told according to this information. Quote: ‘Even though the CO2 emissions continue, atmospheric CO2 levels start to fall around 2060.’
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The goal of reaching “net zero” global anthropogenic emissions of carbon dioxide sounds overwhelmingly difficult.

But that’s not true, because nature doesn’t work that way, says Dr.Roy Spencer (via Climate Change Dispatch).

While humanity continues producing CO2 at increasing rates (with a temporary pause during COVID), how can we ever reach the point where these emissions start to fall, let alone reach zero by 2050 or 2060?

What isn’t being discussed (as far as I can tell) is the fact that atmospheric CO2 levels (which we will assume for the sake of discussion causes global warming) will start to fall even while humanity is producing lots of CO2.

Let me repeat that, in case you missed the point:

Atmospheric CO2 levels will start to fall even with modest reductions in anthropogenic CO2 emissions.”

Last year I published a paper) showing that the record of atmospheric CO2 at Mauna Loa, HI, suggests that each year nature removes an average of 2% of the atmospheric excess above 295 ppm (parts per million).

The purpose of the paper was to not only show how well a simple CO2 budget model fits the Mauna Loa CO2 measurements but also to demonstrate that the common assumption that nature is becoming less able to remove “excess” CO2 from the atmosphere appears to be an artifact of El Nino and La Nina activity since monitoring began in 1959.

As a result, that 2% sink rate has remained remarkably constant over the last 60+ years. (By the way, the previously popular CO2 “airborne fraction” has huge problems as a meaningful statistic, and I wish it had never been invented. If you doubt this, just assume CO2 emissions are cut in half and see what the computed airborne fraction does. It’s meaningless.)

Here’s my latest model [aligned] to the Mauna Loa record through 2023, where I have added a stratospheric aerosol term to account for the fact that major volcanic eruptions actually reduce atmospheric CO2 due to increased photosynthesis from diffuse sunlight penetrating deeper into vegetation canopies:

Continued here.
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Conclusion from the link:
The message here is that CO2 emissions don’t have to be cut very much for atmospheric CO2 levels to reverse their climb and start to fall.

The reason is that nature removes CO2 in proportion to how much excess CO2 resides in the atmosphere, and that rate of removal can exceed our CO2 emissions with modest cuts in emissions.

I don’t understand why this issue is not being discussed. All of the net zero rhetoric I see seems to imply that warming will continue if we don’t cut our CO2 emissions to essentially zero. But that’s not true, because that’s not how nature works.

More here (RS blog post).