|This paper explores the contribution of anthropogenic influence to the EAWM in the past decades, using the All-Hist and Nat-Hist experiments. They found that the weakening of EAWM in 1960-2012 is mainly attributed to the anthropogenic influence, especially in the frequency of weak EAWM occurrence. Their results are reliable, based on the good performance of the model in simulating EAWM. I suggest for publication after minor revision. The details are shown below:|
1. As shown in Figure 2, the EAWM indices in the All-Hist runs during 1960-1970 disagree with the results from reanalysis data. However, the indices during 1970-2013 are closely related to that from reanalysis data. I think it may be due to the uncertainty of the NCEP dataset before 1970. To confirm the relationship, please check the performance of the EAWM indices in the All-Hist runs compared with JRA-55 reanalysis dataset.
2. Why the time series of the EAWM indices in the Nat-Hist runs are standardized by the climatology simulated in the All-Hist runs? Does it matter the number of the strong or weak EAWM events?
3. According to previous studies (Zhu et al. 2015; Wei et al. 2017...), climate-decadal variability (such as PDO) associated with SST is important for the change of East Asian summer monsoon and winter monsoon. This paper indicates that the anthropogenic influence may be the main factor for the weakening of EAWM in 1960-2013, so what is the contribution of climate decadal variability related to SST? Is it smaller than the anthropogenic influence?
Zhu Y, Wang H, Ma J, Wang T, Sun J. 2015. Contribution of the phase transition of Pacific Decadal Oscillation to the late 1990s’ shift in east china summer rainfall. J. Geophys. Res. 120:8817–8827.
Wei Y, Yu H, Huang J, He Y, Yang B, Guan X, Liu X (2017) Comparison of the Pacifc Decadal Oscillation in climate model simulations and observations. Int J Climatol. https://doi.org/10.1002/joc.5355
4. Line 17, “… monsoon can be greatly influenced …” can be changed to “… monsoon is greatly influenced …”.
5. Lines 186-188, “Meanwhile, in the high-level troposphere, … over the high-latitude regions under the anthropogenic influence”; Line 195, “ a decrease of SLP in the mid-latitude East Asia”. I suggest that more details should be provided in these descriptions.
6. Line 204, “Interestingly, the two simulated EAWM indices …”. “Interestingly” is redundant.
7. Line 238, “the interannual and interdecadal variation of the EAWMI_HGT…”. The “variation” should be “variations”.
8. Line 489, “… and 850 wind …” should be “… and 850 hPa wind …”.