Evolutionary association rules for total ozone content modeling from satellite observations

a r t i c l e i n f o In this paper we propose an evolutionary method of association rules discovery (EQAR, Evolutionary Quantitative Association Rules) that extends a recently published algorithm by the authors and we describe its application to a problem of Total Ozone Content (TOC) modeling in the Iberian Peninsula. We use TOC data from the Total Ozone Mapping Spectrometer (TOMS) on board the NASA Nimbus-7 satellite measured at three locations (Lisbon, Madrid and Murcia) of the Iberian Peninsula. As prediction variables for the association rules we consider several meteorological variables, such as Outgoing Long-wave Radiation (OLR), Temperature at 50 hPa level, Tropopause height, and wind vertical velocity component at 200 hPa. We show that the best association rules obtained by EQAR are able to accurate modeling the TOC data in the three locations considered , providing results which agree to previous works in the literature. Modeling ozone series from satellite observations, past data and its relationship with meteorological variables is an important topic quite often tackled in the literature [1–11]. The interest in modeling ozone series started on the early 70's, when changes into the strato-spheric ozone were claimed to be caused by catalytic reactions in the stratosphere that originated losses in the total amount of ozone [12,13]. More specifically, other studies on this topic focused on the role of chlorine [14] and the CFCs [15] in ozone losses at the stratosphere. Those theories were confirmed by the observation of a sharp decrease in the stratospheric ozone levels over Antarctica at the start of the southern spring season in the middle 80's over several polar bases of this continent [16]. A wide review on concepts and history of ozone depletion can be found in [17,18]. In recent years, ozone variation has been related to climate change, so ozone modeling has become an important indicator of deep changes in the atmosphere. That is why very different approaches can be found in the modeling of ozone series in recent bibliography. Specifically, a large amount of works dealing with Total Ozone Content (TOC) of the atmosphere have been published in the last few years, since it seems that variations in these TOC series are a more complete indicator of climate change than only stratospheric ozone series. Thus, there are important works devoted to comparison of different satellite and terrestrial measurements of TOC over different sites [19–21]. The …