|Review of esd-2016-39-R1:|
Current challenges of implementing anthropogenic land-use and land-cover change in models contributing to climate change assessments
The authors have done a tremendous job of revising this manuscript. It is better organized, more clear and consistent, and overall a very good paper that explains, demonstrates, and proposes advances to three major challenges of global lulcc in the context of earth system modeling. The authors responded very well to all the reviewers’ comments, and I don’t have any major concerns with this version. I suggest some minor clarifications/edits below, and am looking forward to seeing this paper published soon.
page 3, lines 13-16:
This sentence is awkward. Should there be an “and” in place of the comma between “studies” and “reviews” (two serial clauses), or is there a third serial clause associated with “…in the context…” that needs a verb?
It also may be helpful to state the three challenges here.
page 3, line 26:
“e.g.” is not needed here. If you are concerned that this implies that nothing else can ‘jump,’ you can try something like “Corresponding jumps in carbon and nutrient…”
page 4, line 5:
Figure 1 doesn’t really illustrate this point (it may work better for the next sentence). More appropriate would be table of the independent data sets (refer to Table S1 and maybe add the future projections to it?).
page 4, lines 32-33:
Awkward sentence. If it is ‘within’ the data, how is it not considered?
page 5, line 20:
page 6, line 2:
“providing land-use data to climate models” isn’t necessary here
page 7, lines 10-11:
This more general definition does not make sense to me. Just because an area change is not included in a product does not mean it is a gross change. It could be that a particular category is not represented, which is different than a gross change.
page 8, line 6:
Is there a context for this 40-year period? Is it based on current day statistics/assumptions? Is it a projection of historical baselines? Is it a future projection?
page 11, line 19:
Is this the same simulation as above?
page 13, lines 8-14:
This seems incomplete, and the example given is likely not universal, and is not correct depending on the maps in question.
First of all, there are more cases: exact match, lu ag on natural lc, lc ag on natural lu, and spatial combinations/redistributions of the latter two.
It would seem that transition matrices would work best with the exact match, and would pose challenges for all other cases. But the result (in terms of which cover to convert) of applying of the matrices to the mismatched land cover in each cell would be dependent on the given transitions and land use/cover in each cell, even if using a single set of rules to apply the matrices (these rules will also have uncertainty).
page 15, lines 4-5:
This isn’t necessarily the case if the DGVM is designed to accommodate integrated land cover and land use dynamics.
page 15, lines 9-17:
The introduction of the ‘offline’ strategy is a bit confusing here, especially since the next sentence does not explain it, but rather asks for an integrated framework. It sounds like you refer the ‘ways forward’ as the decoupled strategy, then want to discuss ‘offline’ coupling which needs to be defined here, all leading up to full integration. Maybe the topic sentence should present this progression, then the text can walk through each in turn. Currently, the “land use, land cover and the climate system…” sentence is out of place.
page 15, line 17:
I recommend the terminology of “preliminary results of the iESM.” The “first” results, based on a completed feedback coupling experiment, are still in in review.