[skybrian]

Hmm, I didn't see where it says 10 GtC/year, but perhaps I missed it. Could you be more specific?

Looking at Figure 2.7 [1] they have "Fossil fuels and industry" at what looks like about 37, which agrees with your other source?

The discrepancy in numbers might just be from measuring different things.

[1] https://science2017.globalchange.gov/chapter/2/

[tunesmith]

Key finding #4 in your first link: "The present-day emissions rate of nearly 10 GtC per year suggests that..."

[skybrian]

It seems to be the difference between carbon emissions and carbon dioxide emissions. From a different web page:

"Global carbon (C) emissions from fossil fuel use were 9.795 gigatonnes (Gt) in 2014 (or 35.9 GtCO2 of carbon dioxide)."

https://www.co2.earth/global-co2-emissions

Carbon's atomic mass is about 12 and oxygen about 16. CO2 is about 27% carbon by weight.

[tunesmith]

Oy. Thanks. I'm really getting a lesson on reading these things more closely.