This manuscript presents a rigorous analysis of the regional and temporal trends in the sensitivity of PM2.5 to temperature across CONUS. The improved model modifications (e.g. using GFED4, including the SOA coating effects, and the scaling of SO2 emissions) yield outputs that agree sufficiently well with observations, for the most part. Moreover, the breakdown quantifying the contributions of individual processes within the model is significant in advancing the study of model evaluations and design beyond simple observational correlations. However, the analysis reveals a few structural and methodological issues that, if addressed, would greatly increase the paper's overall impact and credibility.

1.  Addressing discrepancies in the representation of nitrate with temperature: 

The model's strong negative correlation for nitrate and the resulting bias in ammonium sensitivity represent the most persistent and significant discrepancy between simulations and observations in the Eastern and Central US. I suggest using the decomposition approach to try and quantify the relative contribution of competing effects in driving the negative nitrate bias. For example, discerning between the sensitivity of the gas-particle partitioning with temperature and the sensitivity of NOx emissions with temperature.  

2. Addressing uncertainty in the decomposition of individual processes

The decomposition of the total sensitivity into contributions from precursors relies on a linear regression of detrended anomalies as a proxy for partial derivatives. While the results generally align with the total sensitivity, the acknowledged interdependencies among variables suggest this simplification may introduce uncertainty. To increase the robustness of this quantification method, I might include a simple uncertainty assessment, even if only for a smaller (but key) representative region (e.g. SO4 in the Southeast US). This could involve demonstrating that the derived process sensitivities are robust across different rolling temporal windows or alternative detrending methods. 

3. Addressing outlying regarding wildfire OA sensitivity in the Western US

The authors acknowledge that the significant OA sensitivity overestimation in the Western US in more recent years (2016-2022) could be attributed to extreme values in the GFED4 inventory. However, it might be more impactful to reframe this occurrence, rather than with a critique of the GFED4 inventory itself but with an acknowledgment that the current CTM framework does not handle these extreme events well. The modeling of the impact of future wildfires will always carry significant uncertainty, and for certain regions of the US, this inability to accurately predict wildfire contributions has a large impact on overall PM2.5 projections. However, it’s clear that the wildly exaggerated modeled primary OA sensitivities (as shown in Figure 2) are obfuscating trends in SOA that are perhaps more useful to focus on in designing CTMs. Indeed, the scaling on row b of Figure 2 makes discerning trends very difficult prior to the sudden increase. (This criticism is one that I would apply to many of the figures in this manuscript, text is too small, plots are too crowded, and it is a struggle to try and make sense of things). 

4. There are minor grammatical inaccuracies throughout. I’ll list some examples here, as shown from Lines 695-708. My suggestions are written in capitalized letters.

“We quantified the contributions from THE temperature-dependence of isoprene and sulfate to ISOAAQ sensitivity.”

“Given the important role of gas-phase production in MODULATING sulfate sensitivity, as indicated by our findings, we further quantified the contributions from the temperature response of precursors of THE gas phase reaction… and THE cloud fraction to sulfate temperature sensitivity.”

“The long-term temporal pattern of THE temperature sensitivity of sulfate is mainly driven by the decreasing response of SO2 concentrations to temperature as SO2 emissions declined OVERALL.” (Remove “rise” to make the sentence flow better).

“For monoterpene SOA, gas-particle phase partitioning plays a significant role in overall sensitivity, while its dependence on precursor concentrations, including monoterpeneS, ·OH, and NOₓ, collectively contributes to interannual variability.” (I think monoterpenes should be pluralized here, to indicate the full class of molecules.)

I picked this paragraph as an example, but similar grammatical inconsistencies are found throughout the paper. I suggest doing a full round of edits looking specifically at the wording.