General comment

The manuscript by Duan et al describes a significant database of eddy-covariance and micro-meteorological measurements in a typical East Asian monsoon region of China. The data quality control for EC data is introduced in detail, and the manuscript also presents the variations of each variable at diurnal, daily and monthly scales, to some extent, indicating that the data accuracy is reasonable. This dataset will contribute to multiple research fields, including studying land–atmosphere interaction, improving the boundary-layer parameterization schemes, evaluating remote sensing algorithms, and developing climate models in the typical East Asian monsoon region. The manuscript is well written and documented, and I suggest it will be published after some revision.

Major comments:

[1] The description of the time used is unclear in the data file. Is it local time or UTC?

[2] For long term data sets, sensor calibration is important, especially for radiation measurements. The sensor calibration in the current Manuscript may need to be supplemented.

[3] Define the radiation, turbulent, and CO₂ flux direction in section 2.4.

Minor comments:

Line 20: “four component radiation components” should be “four radiation components”.

Line 43: replace the word “influence” with “influenced”.

Line 45: change the word “both co-exist” with “both of them co-existed”.

Lines 69–72: the sentence is better to modified as follows: “Although China Meteorological Data Service Center (http://data.cma.cn/en, last access: 30 April 2022) has provided some meteorological data in recent years, EC sensors have not been commonly equipped in those meteorological stations, making it difficult to obtain heat and CO₂ flux data at some specific places or periods (Flerchinger et al., 2009).”

Line 151: change “Kljun et al. (2015) footprint model” to “the footprint model proposed by Kljun et al. (2015)”.

Line 174: add the word “and” before “P is the air pressure (hPa)”.

Line 178: “Where” should be “where”.Figure 7e: The unit of albedo should not be “W m^–2”.

The authors produce a long-term eddy-covariance data set from two wheat-rice rotation cropland sites and two suburb sites in a typical East Asian monsoon region of Eastern China. They present and evaluate the general meteorological data, radiation data, turbulent fluxes, and CO₂ fluxes. The descriptions of the sites and methods are clear. They provide a valuable dataset, and the results are publishable. Therefore, I would like to suggest some adjustments that may help improve the study. 

Major comments:As a descriptive manuscript related to the field monitoring data, it should present the details about the instruments and data process as much as possible. For example, what are the operating range, accuracy, and precision of the sensors used? How to process the data gaps in the datasets? Was in-filling performed on these gaps?  

Minor comments:

Lines 123–125: The installation height of the four-component net radiometers at SX-cropland and DS-suburb sites were the same. Please write them together as follows: “The four-component net radiometers (CNR-4, Kipp & Zonen B.V., Delft, the Netherlands) were mounted at 1.5 m for SX-cropland and DS-suburb, 3 m for DT-cropland, and 26.5 m above ground level (AGL) for XZ-suburb sites, respectively.”

Lines 128–132: Similarly, the installation heights at four sites for air humidity, air temperature and surface air pressure were the same. Please combine them.

Line 169: change “λET” to “λE”.

Lines 277–280: the sentence is better to be modified as follows: “Take the Year 2016 as an example, λE dominates the land–atmosphere heat flux exchange at two cropland sites (SX-cropland and DT-cropland). However, the dominant consumer of the R_n fluctuated between λE and H at two suburb sites (XZ-suburb and DS-suburb), which could subsequently modulate the local climate.”

Lines 260 and 263: “DT-Cropland” should be “DT-cropland”.

Figure 1b: change the label “SX-cropand” to “SX-cropland”.