Concentration of particles larger than 2.5 nm collected during the Arctic Ocean 2018 expedition

Andrea Baccarini, Julia Schmale, Josef Dommen

The concentration of particles larger than 2.5 nm was measured with an ultrafine condensation particle counter (UCPC). The concentration was corrected for diffusional losses in the inlet based on the neutral cluster and air ion spectrometer (NAIS) size distribution.

The concentration and temporal dynamics of small particles is fundamental to characterize the first step of new particle formation (NPF) and growth. Newly formed particles can grow to larger sizes where they act as cloud condensation nuclei, directly affecting the Earth radiative budget and cloud properties.

Measurements were performed on the 4th deck of icebreaker Oden during August and September 2018 along the track of the expedition. The concentration is reported as particle per cubic centimeter in 60 seconds average.

Citation

Andrea Baccarini, Julia Schmale, Josef Dommen (2020) Concentration of particles larger than 2.5 nm collected during the Arctic Ocean 2018 expedition. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/oden-ao-2018-aerosol-ucpc-1

References

Baccarini A, Karlsson L, Dommen J, Duplessis P, Vüllers J, Brooks IM, Saiz-Lopez A, Salter M, Tjernström M, Baltensperger U, Zieger P, Schmale J (2020) Frequent new particle formation over the high Arctic pack ice by enhanced iodine emissions. Nature Communications 11:4924. https://doi.org/10.1038/s41467-020-18551-0

Kangasluoma J, Attoui M (2019) Review of sub-3 nm condensation particle counters, calibrations, and cluster generation methods. Aerosol Science and Technology 53:11. https://doi.org/10.1080/02786826.2019.1654084

Data description

Raw data were collected at 1 Hz frequency and then averaged for 60 s in order to improve the signal to noise ratio. The datetime is reported in the UTC timezone as yyyy-mm-dd HH:MM:SS.

Data are reported as particle number concentration per cubic centimeter. The nominal particle diameter cut-off corresponding to a 50% detection efficiency of the UCPC is reported to be equal to 2.5 nm; we did not characterize the transmission efficiency directly. The instrument was operated in high flow mode (1.5 lpm) to reduce diffusional losses.

We used an Hampel type filter to remove outliers and spikes related with short-term instrument malfunctioning (e.g. flow variations). The last column in the dataset is a flag to separate between clean data and data that are potentially influenced by the ship exhaust: 1 indicates clean data and 2 contaminated data.

The UCPC model 3776 manufactured by TSI was used. A description of the instrument is provided by Kangasluoma et al. (2019).

Comments

The ship track with latitude and longitude information can be found in the Navigation, meteorological and surface seawater data from the Arctic Ocean 2018 expedition data set.

The data creator ORCIDs are the following:

• Andrea Baccarini: https://orcid.org/0000-0003-4614-247X
• Julia Schmale: https://orcid.org/0000-0002-1048-7962
• Josef Dommen: https://orcid.org/0000-0002-0006-0009

Data were collected during the Arctic Ocean 2018 expedition on board the Swedish icebreaker (I/B) Oden, which was organized by the Swedish Polar Research Secretariat. The observations were part of the project ‘Aerosol-cloud interactions in the High Arctic’ (PI Paul Zieger, Department of Environmental Science, Stockholm University; see MOCCHA project website with updates).