Aerosol number concentrations and size distributions at Syowa Station were measured by optical particle counters from April 1997 to December 2023. 

Details of observatory for aerosol measurements were shown by Hara et al. (2023, 2024). Details of OPC measurements and procedures for data screening of local contamination were mentioned by Hara et al. (2025).

Here, the screened hourly-mean aerosol data are published. File names are based on the following format.

YYYY_OPC_hourly_XXXX.txt

YYYY and XXXX indicate year and OPC model.

In aerosol data taken by TD-100 and TD-200 models, data fields are shown in as follows.

Date time UT: Universal time (UT) was used in the OPC records. Difference between UT and local time (LT) was 3 hours (LT = UT + 3 hours).

Then, hourly-mean aerosol number concentrations in the respective size ranges are shown.

Mean Conc >0.3 um
Mean Conc >0.5 um
Mean Conc >1.0 um
Mean Conc >2.0 um
Mean Conc >3.0 um
Mean Conc >5.0 um

In aerosol data taken by KC-03 and KC-01E models, data fields are shown in as follows.

Date time UT: Universal time (UT) was used in the OPC records. Difference between UT and local time (LT) was 3 hours (LT = UT + 3 hours).

Then, hourly-mean aerosol number concentrations in the respective size ranges are shown.

Mean Conc >0.3 um
Mean Conc >0.5 um
Mean Conc >1.0 um
Mean Conc >2.0 um
Mean Conc >5.0 um

Term of "NA" in the data files indicates no data due to mechanical troubles and local contamination.

All concentrations are the concentrations under ambient pressure air conditions.

Other data such as raw data and high-time-resolution data can be provided by requests.


References

Keiichiro Hara, Kazuo Osada, Masanori Yabuki, Masahiko Hayashi, Masataka Shiobara, Naohiko Hirasawa, and Takashi Yamanouchi, Long-term monitoring of condensation nuclei concentrations at Syowa Station, Antarctic, Polar Data Journal, 7, 13-23, doi/10.20575/00000045, 2023.

Keiichiro Hara, Kazuo Osada, Masanori Yabuki, Masataka Shiobara, Naohiko Hirasawa, and Takashi Yamanouchi, Long-term measurements of black carbon concentrations at Syowa Station, Antarctic, Polar Data Journal, 8, 55-66, doi/10.20575/00000056, 2024.

Hara, K., Osato, K., Yabuki, M., Osada, K., Hirasawa, N., Shiobara, M., and Yamanouchi, Antarctic Haze Phenomena at Syowa Station, Antarctica: Seasonal features and impacts on atmospheric chemistry, npj Climate and Atmospheric Sciences, Revised.