The manuscript presents a timely and scientifically significant investigation into how China’s "Clean Air Action" has affected the terrestrial carbon cycle. I recommend that this manuscript be accepted subject to minor revisions along the lines below. 

1. The manuscript reports many national totals to two decimal places, e.g.,  17.93 TgC.  Please consider rounding key values more appropriately.

2. The abstract is clear, but the sentence “reversed the dominant atmospheric drivers” is too strong unless supported by a true combined simulation with interactive effects considered. Please reword it. 

3. The meaning of “open” in Table 1 should be replaced by more precise wording, such as “enabled” or "on."

4. For the aerosol run, is only aerosol–radiation interaction active, or are aerosol–meteorology feedbacks also active? Please clarify this in Table 1. 

5. Could you describe simply how the carbon-nitrogen cycle is treated in the model? For CLM5, the FUN module is developed to simulate plant nitrogen uptake and nitrogen-carbon interactions. What is the difference between your model and FUN?

6. Line 596-597, as both scattering and absorbing aerosols were reduced, the clarification of enhanced scattering is required. 

7. NEP is a net result of NPP and heterotrophic respiration. How does the heterotrophic respiration respond to these atmospheric drivers?

Please see my comments in the supplement.