The manuscript compiles raw SSD observational data from 1961 to 2022 across over 2,200 stations in China, addressing the known day0-type discontinuity post-2019 instrument updates. This contributes significantly to understanding global dimming and brightening phenomena and their implications for solar energy planning and agricultural management. The originality lies in providing a 62-year homogenized daily SSD dataset, which is a valuable resource for the research community. But I am concerned about the following points：

Major comments:

1. The study concludes that the homogenized SSD dataset more accurately describes the dimming phenomenon. This is an important finding, but the authors must ensure the statistical significance of this conclusion and further explain its scientific implications in the discussion.

2. The manuscript has developed a homogenization procedure to produce a 62-year (1961-2022) homogenized daily SSD dataset in China. However, there is a concern about the incorporation of MERRA2 as a reference series when establishing the ERA5 SSD reference series, which may introduce uncertainties from two different reanalysis data sets. It is essential to explain how these uncertainties are mitigated and their potential impact on the study's results.

Some minor comments：

1. Some sentences are structurally complex, which may hinder understanding. The authors are encouraged to simplify these sentences to make the article more accessible.

2. Comparison with Other Studies: The authors should discuss how their findings compare with those of other studies. If the results are inconsistent with other research, the reasons for these discrepancies should be explored.

The authors made significant efforts to integrate observational data of sunshine duration in China, including for the first time to address a sharp drop in zero-value frequency after 2019 caused by the instrument upgrade and to adjust inhomogeneities of its long-term series. This produces the first homogenized daily observational dataset of sunshine duration over China from 1961 to 2022. This effectively addresses critical gaps in data availability and homogeneity of sunshine duration observation providing a crucial dataset to accurately assess the dimming and brightening and to support other practical applications. The manuscript is well-structured, clearly presenting the research goals, statistical methods, dataset description, and results.

The manuscript is recommended for publication with minor revisions as specified below:

1. It’s not clear if the presentation of spatial patterns of regression slopes (α, β, γ in Section 2.3.2) aids to understand the use of reference series during the homogenization. Could you plot them and assess their necessity in the main text?
2. Even though the methods used in the homogenization are widely recognized, a concise description of PMF and PMT test algorithms should be included to help understand the detected breakpoints in Section 2.3. Additionally, more details of the improved K-S test should be added in Section 2.3.1 to enhance its readability.
3. Provide additional details on daily cloud cover fraction and aerosol optical depth at 500nm (AOD) from MODIS in Section 2.1 to help understand their relationships with sunshine duration in the following text.
4. Line 298: Please clarify how to calculate the hit probability of 65%.
5. The subfigure in Figure 6 is too small to be easily readable. Please revise it.