Dear Genard-Zielinski et al.,
I am pleased to accept the manuscript for publication in the ACP. However, the language of the ms could be improved. Copy-editing of the manuscript will be done by the editorial office, but prior to that, below is a list of technical corrections I suggest.

Sincerely,
Janne Rinne

Please spell out terms such as T, RH, rather than use abbreviations. It is much easier read the text with “temperature” or “relative humidity” rather than “T” or “RH”. Only use abbreviations for longer terms (more than three words or so).

The terms from equations, such as Pn, Gw, etc, should be italicized when used in text.

Usage of significant digits: In many cases you report emissions using three significant digits (there is an example below). This implies an accuracy in the order of 1 %. As the number of significant digits should reflect the accuracy of the number, I believe two significant digits to be enough in most cases.

Specific comments

Page 3, line 67: Replace “2” by “two”

Page 3, lines 80-82: “In Europe, Quercus pubescens Willd. accounts for the most important isoprene emitter species, and represents thus one of the first biogenic isoprene source in the Mediterranean region (Keenan et al., 2009)”. This sentence is awkward and partly misleading. I suggest “In Europe, Quercus pubescens Willd is one of the most important isoprene emitter species, and represents thus one of the most significant biogenic isoprene sources in the Mediterranean region (Keenan et al., 2009)”.

Page 3, line 83: “fluctuate”, maybe “vary” would be better as fluctuation usually refers to temporal fluctuations.

Page 5, line 121: “downy oak”. Please include the scientific name (Q. pubescens) in parentheses as a reader of ACP does not necessarily connect the common name and scientific one.

Page 5, line 133: “experimentation”, replace by “experiment”.

Page 5, line 140: “…pubescens sunlit branches…” should be “…pubescens on sunlit branches…”

Page 6, line 153: “…were approximately hourly sampled…” should be “…were sampled approximately hourly…”

Page 8, lines 233-234: “Intercomparison exercises between isoprene determination using both, IMBE and LSCE cartridges and the on-line PTR-MS, showed a difference between 4.0 and 8.6 %.” Could you specify if this is mean difference (bias) or root-mean-square difference?

Page 11, lines 331-332: “The remaining 1.2 % was found to represent a negligible quantity of the carbon 331 assimilated as BVOC (< 0.03 %),” Do you mean carbon assimilated as CO2?

Page 12, lines 347-348: “its maximum relative contribution to the emitted carbon was observed 347 at dawn (6.88 % data not shown)…” You probably refer to carbon emitted as BVOCs, i.e. excluding respiration of CO2?

Page 14, line 410: “alter, either,” should be ““alter either”, (no commas).

Page 15, line 435: “top canopy branches” would be better as “top of the canopy branches”

Page 15, line 437, and elsewhere: “97.7 μgC gDM-1 h-1”. Is three significant numbers reasonable? This implies accuracy in order of 1% of measured emission. Probably 98 μgC gDM-1 h-1 would be more in line with the accuracy.

Page 15, lines 452-453: “2/3 of the isoprene emission 452 rates measured from the studied branches exponentially increased with Pn” Do you mean that the relation was observed in 2/3 of the observed trees?

Page 17, line 517: “the 7 sunlit”, should be “the seven sunlit”. Similarly in many other places integers below or equal to ten should be written in letters.

Page 18, line 536: “dependant” should be “dependent”.

Page 21, line 643: “both, sunlit” should be “both sunlit”.

Page 22, line 650: “tree-to-tree and branch to branch” should be either “tree-to-tree and branch-to-branch” or “tree to tree and branch to branch”