The past week brought a mixed bag of news to my mailbox. The world’s population was estimated to have passed 8 billion folks, each with the desire to be a consumer at the level of Western economies. Of course, economists herald consumers as the key to the Holy Grail of economic growth. This was good news for economists.

Reassuringly, The Economist tells me that in many countries, perhaps totaling 1 billion people, economic growth is now decoupled from higher carbon emissions, due to increased energy efficiencies and increasing installations of renewable energy.  In the U.S., population increased about 7.3% since 2010, while CO₂ emissions declined about 12% in the same period. This is good news if we can implement these improvements worldwide. But we must also ensure that the pursuit of specialty metals for renewables doesn’t dig up the entire surface of the Earth.

As COP-27 opened in Egypt, scientists estimate that by year’s end, carbon dioxide emissions in 2022 will exceed those of 2021. This is bad news, if we hope to confine the increase in the Earth’s surface temperature to less than 2^o C by the end of the century.  Despite the correlation published by Hofmann and his colleagues in 2008, I have yet to see any public recognition that growing human population leads to higher emissions. Once again, I note that the child not born consumes nothing.

Finally, in the pages of Nature, I found an article now estimating that the cost of carbon dioxide emissions (per ton) to the economy now appears to be about $185—or $6.8 trillion per year at today’s CO₂ emissions of 37,000,000,000 tons each year. Droughts, wildfire, rising sea level, and pandemic diseases take their toll. How long can the world sustain this drain on its economy?

The continued belief that rising human numbers have no impact on the environment is misguided. How will the world’s biodiversity will fare as we clear land to feed and house the rising number of humans?  (See https://blogs.nicholas.duke.edu/citizenscientist/overpopulation/)  Both human numbers and consumption enhance impacts; whereas, innovative technologies can reduce them.  We need to work on all variables in the equation.

 

References

Coalbrookdale and S. El-Sheikh. 2022.  Green Light.  The Economist, November 12, p. 65-66

Hoffman, D.J., J.H. Butler, and P.P. Tans. 2008.  A new look at atmospheric carbon dioxide.  Atmospheric Environment 43: 2084-2086.

Rennert, K., and 23 others. 2022.  Comprehensive evidence implies a higher social cost of CO₂.  Nature 610: 687ff.