Text Correction
We believe that several sentences in the description of the source (sink) changes of CO
2 are prone to ambiguity and are not particularly well presented. There were errors in the original publication [
1].
- 1.
The original sentence was located in **Abstract**, **Paragraph 1**, **Penultimate sentence of the abstract**:
**The mean global daily CO2 flux estimated based on the nocturnal effect and the sub-regional pCO2w algorithm (cor_Fcom) was −6.86 mol m−2 y−1 (September 2020–August 2021), which was smaller by 0.75 mol m−2 y−1 than that based solely on the sub-regional pCO2w algorithm (day_Fcom)**.
A correction has been made to **Abstract**, **Paragraph 1**, **Penultimate sentence of the abstract**:
**The mean global daily CO2 flux estimated based on the nocturnal effect and the sub-regional pCO2w algorithm (cor_Fcom) was −6.86 mol m−2 y−1 (September 2020–August 2021), which was greater by 0.75 mol m−2 y−1 than that based solely on the sub-regional pCO2w algorithm (day_Fcom = −7.61 mol m−2 y−1)**.
- 2.
The original sentence was located in **Abstract**, **Paragraph 1**, **Last sentence of the abstract**:
**That is, compared with day_Fcom, the global cor_Fcom value overestimated the CO2 sink of the global ocean by 10.89%**.
A correction has been made to **Abstract**, **Paragraph 1**, **Last sentence of the abstract**:
**That is, compared with cor_Fcom, the global day_Fcom value overestimated the CO2 sink of the global ocean by 10.89%**.
- 3.
The original sentence was located in **Results and Discussion**, **3.5.2. Estimation of the CO2 Flux Using the Nocturnal Effect**, **Paragraph 3**, **Last three sentences of the paragraph**:
**Specifically, compared with day_Fcom, the global cor_Fcom value increased by 4.90 × 10−4 mmol m−2 d−1, thereby overestimating the oceanic CO2 sink by 10.21%. The mean monthly increase was 2.50 mmol m−2 month−1, thus overestimating the mean oceanic CO2 sink by 10.68%. The mean annual increase was 0.75 mol m−2 y−1, thereby overestimating the mean oceanic CO2 sink by 10.89%**.
A correction has been made to **Results and Discussion**, **3.5.2. Estimation of the CO2 Flux Using the Nocturnal Effect**, **Paragraph 3**, **Last three sentences of the paragraph**:
**Specifically, compared with day_Fcom, the global cor_Fcom value increased by 0.18 mmol m−2 d−1, thereby day_Fcom overestimating the oceanic CO2 sink by 10.21%. The mean monthly increase was 2.50 mmol m−2 month−1, thus day_Fcom overestimating the mean oceanic CO2 sink by 10.68%. The mean annual increase was 0.75 mol m−2 y−1, thereby day_Fcom overestimating the mean oceanic CO2 sink by 10.89%**.
- 4.
The original sentence was located in **Conclusions**, **Paragraph 5**, **Last three sentences of the paragraph**:
**Compared with day_Fcom, the global cor_Fcom value was greater by 4.90 × 10−4 mmol m−2 d−1, thereby overestimating the oceanic CO2 sink by 10.21%. The mean monthly increase was 2.50 mmol m−2 month−1, thus overestimating the mean oceanic CO2 sink by 10.68%. The mean annual increase was 0.75 mol m−2 y−1, thus overestimating the mean oceanic CO2 sink by 10.89%**.
A correction has been made to **Conclusions**, **Paragraph 5**, **Last three sentences of the paragraph**:
**Compared with day_Fcom, the global cor_Fcom value was greater by 0.18 mmol m−2 d−1, thereby day_Fcom overestimated the oceanic CO2 sink by 10.21%. The mean monthly increase of cor_Fcom was 2.50 mmol m−2 month−1, thus day_Fcom overestimated the mean oceanic CO2 sink by 10.68%. The mean annual increase of cor_Fcom was 0.75 mol m−2 y−1, thus day_Fcom overestimated the mean oceanic CO2 sink by 10.89%**.
- 5.
We want to add the following two sentences on CO2 source and sink to **Introduction**, **Paragraph 2**, after the phrase:
**At present, the sea–air CO2 flux can be measured directly using the eddy correlation method. Alternatively, the CO2 flux is often calculated by the block method formula [4], as follows: sea–air CO2 flux = sea–air gas transfer velocity × solubility of CO2 in seawater × (pCO2 in seawater–pCO2 in air)**.
The added sentence is:
**If the CO2 flux is positive, it means that CO2 enters the atmosphere from the ocean, i.e., the ocean is the source of CO2. If the CO2 flux is negative, it means that CO2 enters the ocean from the atmosphere, i.e., the ocean is the sink of CO2**.
The authors apologize for any inconvenience caused and state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.