The dataset contains two tables, one for positive ions and another for negative air small ions. The tables are presented in the form of text files, where the values within two different sequential columns are separated by one tabulator. Such text files can be imported into several software programs, including MS Excel.
The dataset provides a sample of the results obtained by measurements of the mobility distributions of one-second-aged corona-generated ions formed in the ambient atmospheric air. It presents the detailed mobility distribution of these ions between 0.6 and 2.8 cm2V–1s–1. The mobility equivalent diameters are between about 0.42 and 1.5 nm. The genesis and subsequent evolution of air ions is a key to understanding the formation of atmospheric aerosols, which is an essential factor of the Earth's climate. In particular, the chemical composition of small air ions is known to be sensitive to the concentrations of several air trace gases. Our data are substantially different from the ones obtained by a relatively widespread technique that is also called “ion mobility spectrometry” but commonly measures the ions that are only few milliseconds old. The data also differ from the ones, obtained by widespread routine measurements of natural ion composition. Our unique measurement device can deliver the results that allow to derive certain scientific results, not attainable from other data.
The dataset includes results of simultaneous measurements of the positive and negative ions generated in the ambient outdoor air during three months of year 2011. The devices were located in a building within a small town. The air ion measurements are accompanied with basic meteorological data. The dataset is not designed for direct running via the Internet. Complete package that contains data and explanations should be downloaded from the website and operated in the personal computer of the scientist. The data are saved as tab-delimited text files, which also can be opened using MS Excel. The author acknowledges Kaupo Komsaare for help within the measurements, Jaan Maasepp for technical help, prof. Hannes Tammet for valuable comments and Urmas Hõrrak for supervision of the measurements.
