A complexity analysis of 222Rn concentration variation: A case study for Domica cave, Slovakia for the period June 2010–June 2011

• We have analyzed annual 222Rn concentration variation in Domica cave (Slovakia).
• We have applied a complexity analysis on 222Rn concentration time series.
• We have suggested novel complexity measures based on the Kolmogorov complexity.
• We have analyzed dependence of 222Rn time series on cave environmental parameters.
• We have analyzed stochasticity in 222Rn concentration time series.

In this paper we have analyzed 222Rn concentration variation in Domica cave (Slovakia) for the period June 2010–June 2011. In that sense we have applied a complexity analysis on 222Rn concentration time series. We have considered possible existence of a periodical component in the variation of 222Rn concentration and some environmental parameters, as well as possible correlation between them. In addition we have offered novel complexity measures based on the Kolmogorov complexity (KC), i.e. the Kolmogorov complexity spectrum, its highest value (KCM) and the integral Kolmogorov complexity (KCI). These measures have been applied on 222Rn concentration time series: (i) to establish the dependence of 222Rn concentration on cave environmental parameters (wind speed inside the cave, external wind speed, air temperature, atmospheric pressure and CO2 concentration) and (ii) to see whether influence of some parameters make the distribution of measured quantity less or more stochastic.