review  attached

This paper presents an experimental and numerical study of the atmospheric oxidation of methyl pivalate (MPA) and pinacolone (PCO), both considered as “green” solvents. First, the reactions rate constants of MPA and PCO with OH radicals are measured using the PLP-LIF (Pulsed Laser Photolysis – Laser Induced Fluorescence) technique in the temperature range (295-485 K), showing results in line with the scarce data from the literature. UV-Vis absorption cross sections of PCO were also obtained experimentally (in liquid phase) and numerically, and compared to data for MEK (Methyl Ethyl Ketone). The authors also propose an estimation of the photolysis rate coefficients for PCO. Finally, lifetimes for removal of PCO and MPA from the troposphere are calculated, suggesting relatively low reactivity of MPA and more reactivity for PCO due to photolysis.

In general, this paper is of good quality, describing a very comprehensive work combining experiments and modelling, even if it is not perfect and leaves open questions, notably because of the lack of comparable gas phase absorption cross sections and quantum yields data for PCO and MPA, the authors must have made approximations.

Minor considerations:

- As mentioned by the authors (line 107): “rate coefficient determinations in this work relied critically on accurate knowledge of [OVOC], here estimated to a precision of ±15%”

Indeed, it is often difficult to accurately determine the concentrations of OVOCs in this type of experiment. It is not clear how the mixtures of different concentrations of MPA and PCO diluted in nitrogen are prepared. It is therefore difficult to understand how the ± 15% uncertainty is estimated. Could the authors give more details on this aspect?

- Concerning LIF measurements (line 116): “This tuneable laser light was used to pump the Q11 transition of A²S⁺(v = 1) - X²P(v = 0) at 281.997 nm for direct, off-resonant LIF detection of OH.”

What does this mean? At which wavelengths are resonance and non-resonance measurements made?

The Q1(1) line of OH is not an isolated line (the R2(3) line is very close)

Does this pose a problem for the interpretation of the LIF results? What is the wavelength resolution?

- line 304: “Considering the systemic errors, we quote more realistic values of k₁ (296 K) = (1.2 ± 0.2) × 10^-12 cm³ molecule^-1 s^-1 and k₂(296 K) = (1.3 ± 0.3) × 10^-12 cm³ molecule^-1 s^-1, that take into account the error over the estimation of [VOC]”

It is not clear how this concentration error is taken into account in the final uncertainty calculation

- Line 177: “Similar experiments were conducted at different temperatures, pressures and in the presence / absence of O₂”

The authors should clarify the value of such measurements (with and without O₂) and at least give an indication of the comparative results