|Review of “Prevailing climatic trends and runoff response from Hindukush-Karakoram-Hiamalaya, upper Indus basin” by Hasson et al.|
This manuscript describe the climatic constraints on water availability of the upper Indus Basin in Pakistan. The authors rely on station data (temperature and precipitation and discharge) which are sparse in this region. The authors make important observations on climate trends and decompose them by season/months. The authors address the topic of the Karakoram Anomaly - this is a timely topic in a region that receives lots of attention, but is characterized by a lack of ground and station data. The authors attempt to fill that niche – although this manuscript is not a presentation of a lot of new station data, it is a very useful overview and synthesis.
Overall, the manuscript is well written, but is certainly on the lengthy and wordy side. In that respect, does the methods section really need the statistical basis of the MK/TS/etc explained with formulas? This seems like a lot of additional material and weight that is not necessary. In short, while the authors are thourough and the manuscript contains important information, it is too long. For example, the results start at line 512 – this is the length of some other entire manuscript. While informative and important, the results of the discharge data alone are 1.5 pages (>40 lines).
Some minor suggestions and wording comments:
I'm also not convinced that the section on trends vs lat/lon is helpful. There should be a lot more local topography impact than pure lat/lon impact (e.g. aspect, distance from mountain front as proxy for rain shadow, distance to local peaks). So, an analysis of trends vs elevation/relief/aspect would be more instructive. Given the length of the manuscript and the focus (and the extensive trend analysis), I suggest to remove this part, because it doesn’t provide the detail and thoroughness as other parts of the manuscript.
L835 they suggest a weakening of the westerlies, which disagrees with other interpretation and literature, and then on the next page suggest an increase in the strength of westerly storms (citing Cannon et al.). This seems inconsistent – please rephrase.
Figure 1: Station locations are difficult to see. I suggest to use a grayscale image for elevation or other symbols. Almost impossible to identify glaciers.
Table 4, 6, and others: I always tend to use one significance level and use ONLY that significance level. Using two significance levels (0.9 vs 0.95) is misleading. Most importantly, that add clutter and noise to the table that is unnecessary.
I am struggling with the last 3 figures (Figure 9-11). While these are useful in terms of data-generation and visualization effort, they do not convey any useful information – unless you are willingly to stare at least 5 minutes at one figure. Grid lines would be helpful, but also an indication what information these figures should convey. As pointed out before, the manuscript would not be weaker, if these are removed. Especially considering the facts that there are a dozen stations over 5 degree of longitude (550 km) in some of the roughest terrain on earth!
IF the authors decide to leave them in, I strongly urge them to revisit them, make colors and symbols clearer and indicate what these are supposed to document (trends)? Otherwise the reader will interpret them as that there is not climatic relation with topography.