TY - JOUR T1 - PROCESSING OCEANOGRAPHIC DATA BY PYTHON LIBRARIES NUMPY, SCIPY AND PANDAS AU - Lemenkova, Polina PY - 2019 DA - April DO - 10.3153/AR19009 JF - Aquatic Research JO - Aquat Res PB - Nuray ERKAN ÖZDEN WT - DergiPark SN - 2618-6365 SP - 73 EP - 91 VL - 2 IS - 2 LA - en AB - Thestudy area is located in western Pacific Ocean, Mariana Trench. The aim of thedata analysis is to analyze the potential influence of how various geologicaland tectonic factors may affect the geomorphological shape of the MarianaTrench. Statistical analysis of the dataset in marine geology and oceanography requires an adequate strategy on bigdata processing. In this context, current research proposes a combination ofthe Python-based methodology that couples GIS geospatial data analysis. TheQuantum GIS part of the methodology produces an optimized representativesampling dataset consisting of 25 cross-section profiles having in total 12,590bathymetric observation points. The sampling of the geospatial dataset arelocated across the Mariana Trench. The second part of the methodology consistsof statistical data processing by means of high-level programming languagePython. Current research uses libraries Pandas, NumPy and SciPy. The dataprocessing also involves the subsampling of two auxiliary masked data framesfrom the initial large data set that only consists of the target variables:sediment thickness, slope angle degrees and bathymetric observation pointsacross four tectonic plates: Pacific, Philippine, Mariana, and Caroline.Finally, the data were analyzed by several approaches: 1) Kernel DensityEstimation (KDE) for analysis of the probability of data distribution; 2)stacked area chart for visualization of the data range across various segmentsof the trench; 3) spacial series of radar charts; 4) stacked bar plots showingthe data distribution by tectonic plates; 5) stacked bar charts for correlationof sediment thickness by profiles, versus distance from the igneous volcanicareas; 6) circular pie plots visualizing data distribution by 25 profiles; 7)scatterplot matrices for correlation analysis between marine geologicvariables. 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