This study systematically analyzed the linkage between the high temperature and soil moisture drought onset, and further considered the influence of vegetation from the perspective of land-atmosphere coupling. The structure of the manuscript is complete and the results are interesting. However, there are many confusing issues (including definition, experimental design and results) in this manuscript, which may affect the conclusions. Therefore, I recommend a major revision of this manuscript. Here are some comments below:

1. The definitions of t₀ are different in the description and Figure 1, which makes me very confused. “The first day that SMP falls below the 40th percentile represents the initiation time (denoted as t0) of the drought event” (Lines 98-99). “the duration of drought onset (DDO) is defined as the time interval between the initiation time of a drought (referred to as t0) and the time when the moisture condition falls into moderate, severe, or extreme drought (referred to as td), denoted as DDO_m, DDO_s, and DDO_e for short, respectively” (Lines 113-115). In Figure 1, which one is t₀, the first blue square, the second blue square or the dot after the second blue square?
2. The design of experimental scenario Ⅱ seems unreasonable. In experimental scenario Ⅱ, the high temperature occurred not only with the varied hitting times, but also with the different durations. Compared to the heating time, the duration of high temperature may be more important. In addition, how did you conclude that the impacts of high temperatures were greatest during the week of drought onset (Line 20)?
3. Figure 3a: The precipitation was positively correlated with the DDO over most areas, why are the boxplots different from the spatial pattern? In addition, please modify the incorrect description in lines 182-184.
4. Figure 5: The frequency and duration of droughts are very unreasonable. How could there have been more than 500 drought events occurring in South China during the past 72 years? In addition, short-term drought events with duration less than one month were excluded given their limited effects on agricultural production and ecological system (Lines 101-102), why are most areas in South China still with a duration of less than 20 days? Please further review the definition and code of drought.
5. It seems that Figure 8 shows the DDO but not the change ratio of DDO. Please modify the y-axis labels and figure caption. The red (orange?) legend makes me confused. Please show the legends of all colors, or show the “25th~75th Percentile” in the suitable position. In addition, please provide the criteria for identifying the sensitive intervals.
6. Lines 284-285: Does Figure 9 show the change ratio of DDO according to equation (3)? It seems that the ratio is negative when the DDO_i decreases, why does a positive value of the ratio mean a decrease in DDO? In addition, please add the colorbar in Figures 9-10.
7. Figure 11: Why is the dotted vertical line located at T₂? Perhaps the dotted vertical line should be located at T₀, which means the drought initiation (Lines 285-286).

Liu et al., Accelerated soil moisture drought onset link to high temperatures and asymmetric responses associated with the hit timing.

Overall, this manuscript is well prepared. A new drought characteristic, the duration of drought onset (DDO) is defined to measure how rapid the drought develops. The results are interesting and meaningful. I recommend to accept this manuscript after minor revisions. Some specific comments are as follows:

1. Introduction: this part seems too short, which does not clearly point out the gaps between existing studies and this study. The authors should further highlight their new contributions to this field.

2. Fig. 1: how to determine the level of DDO? Why 8 days for moderate, 14 days for severe, and 18 days for extreme drought?

3. Line 204: there are also many areas with estimation errors larger than 10 days in the northwest region.

4. Lines 215-216: Why not present the results for DDOe?

5. Lines 242-243: due to global warming, whether 35 ℃ can still be regarded as a threshold of high temperature days needs more discussion.

6. There are some track changes in the main text. Please check carefully.

7. There are also some editing errors in the text. Some examples are as follows: Line 106: "phage"? Lines 269-270: wrong sentence. Lines 281 and 282: "change rate" or "change ratio"? Fig. 11: "ndvi" -> "NDVI". Line 342: the full name of VDP is not given. Line 343: "there virtually no changes"? Line 345: "were" -> "was".