Review of

Investigating the spatial representativeness of Antarctic ice cores: A comparison of ice core and radar-derived surface mass balance

by Cavitte and others

General

The paper deals with an interesting and important topic, representativeness of point SMB observations in Antarctica. But it mainly uses data of ice rises, which are known to have a significant impact on precipitation amounts. This means that the context is different from what the reader could derive from the title, and the title and text should be changed to reflect this. See more detail in Major Comments below. The paper is also overly long and sometimes difficult to read, with rather long-winding sentences, and I invite the authors to attempt to write more concisely and shorten the paper. The figures are of good quality.

Major comments

My main concern is the context and framing of this study. Upon first sight, the study is positioned as quantifying the representativeness of point SMB measurements. This implies that you are mainly interested in the impact of post-depositional processes (sublimation, drifting snow etc.) that introduce SMB differences in otherwise homogenous terrain. But this is not so. The work compares ice core-derived SMB from the summit of ice rises to radar-derived SMB measurements in the vicinity and intersecting the summit. Ice rises cannot be considered homogeneous terrain. Several studies (e.g.: doi:10.3189/2014JoG14J040) show that ice rises cause important depositional (precipitation) SMB gradients, which are qualitatively well understood and modelled. In other words, nobody would normally claim that an SMB record of the ice rise dome is representative for its surroundings. And this paper shows this is indeed the case. This is different for Dome F, where the terrain is smooth, accumulation amounts are much lower, and the topographic precipitation effect is expected to be small. This is confirmed by the much smaller regional differences there. So the authors should include a discussion in which they motivate their choice for using ice rises to address the issue of SMB representativity, and how depositional and post-depositional signals can be disentangled.

l. 18: "However, these data clearly indicate that local spatial SMB variability must be considered when assessing mass balance as well as comparing modeled SMB values to point field data." Yes, but how must they be considered? By assigning an uncertainty to the observation?

l. 23: "rising specific humidity" It is not specific humidity, but the saturation specific humidity that will increase.

l. 29: "The Antarctic coastal region is getting most of the accumulation due to source proximity and low elevation (e.g., Lenaerts et al., 2019)" Yes, but the main reason is topographic precipitation forcing, which also explains why local accumulation rates can be higher over the lower grounded ice sheet compared to the neighbouring flat ice shelves.

Minor comments

l. 1: over -> of

l. 3: validate -> evaluate (this is about models, which cannot be validated by default)

l .8: "between annual and sub-decadal resolution": annual is also decadal, please make more concrete.

l. 14: areas -> area

l. 41: "In addition, it is not simple case of averaging many records in close proximity to reduce noise in ice core records". This sentence is unclear, please reformulate.

l. 58: "...and example their spatial variability referenced co-located ice core SMB". This sentence is unclear, please reformulate.

l. 62: " multi-annual ". Can you be more specific?

l. 64: "lack of surface topography" Do you mean no pronounced surface topographical features? But ice rises can also be featureless. Please be specific and precise.

l. 208-214: Please consider presenting uncertainties wit single decimal (i.e. 1.87 -> 1.9%).