On the role of pre and post-processing in environmental data mining

The quality of discovered knowledge is highly depending on data quality. Unfortunately real data use to contain noise, uncertainty, errors, redundancies or even irrelevant information. The more complex is the reality to be analyzed, the higher the risk of getting low quality data. Knowledge Discovery from Databases (KDD) offers a global framework to prepare data in the right form to perform correct analyses. On the other hand, the quality of decisions taken upon KDD results, depend not only on the quality of the results themselves, but on the capacity of the system to communicate those results in an understandable form. Environmental systems are particularly complex and environmental users particularly require clarity in their results. In this paper some details about how this can be achieved are provided. The role of the pre and post processing in the whole process of Knowledge Discovery in environmental systems is discussed

Modelling the relationship between streamflow and electrical conductivity in Hollin Creek, Southeastern Australia

The relationship between streamfiow q and electrical conductivity k is explored in this paper, using data from Hollin Cave Spring in New South Wales, Australia. A temporal rule extraction algorithm is used to identify frequent patterns in each time series. The frequent patterns are then refined using the concept of profile convexity, and parametrised for compactness of representation, before the coupling between flow and conductivity is examined. Results show that two frequent peak patterns occur in flow and two troughs in electrical conductivity, and that the shapes of all these can be characterised with a single magnitude parameter. The coupling between events in the two series is investigated, and reveals that the depth of k troughs depend heavily on the initial state of k, and more weakly on the magnitude of the flow peak

Climate change 2013: the physical science basis

This report argues that it is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century. This is an an unedited version of the Intergovernmental Panel on Climate Change\u27s Working Group I contribution to the Fifth Assessment Report following the release of its Summary for Policymakers on 27 September 2013.  The full Report is posted in the version distributed to governments on 7 June 2013 and accepted by Working Group I and the Panel on 27 September 2013. It includes the Technical Summary, 14 chapters and an Atlas of Global and Regional Climate Projections. Following copy-editing, layout, final checks for errors and adjustments for changes in the Summary for Policymakers, the full Report will be published online in January 2014 and in book form by Cambridge University Press a few months later