Temporal multiscaling characteristics of particulate matter PM10 and ground-level ozone O-3 concentrations in Caribbean region

摘要

A good knowledge of the intermittency of atmospheric pollutants is crucial for air pollution management. We consider here particulate matter PM10 and ground-level ozone O-3 time series in Guadeloupe archipelago which experiments a tropical and humid climate in the Caribbean zone. The aim of this paper is to study their scaling statistics in the framework of fully developed turbulence and Kolmogorov's theory. Firstly, we estimate their Fourier power spectra and consider their scaling properties in the physical space. The power spectra computed follows a power law behavior for both considered pollutants. Thereafter we study the scaling behavior of PM10 and O-3 time series. Contrary to numerous studies where the multifractal detrended fluctuation analysis is frequently applied, here, the classical structure function analysis is used to extract the scaling exponent or multifractal spectrum zeta(q); this function provides a full characterization of a process at all intensities and all scales. The obtained results show that PM10 and O-3 possess intermittent and multifractal properties. The singularity spectrum M-S(alpha) also confirms both pollutants multifractal features. The originality of this work comes from a statistical modeling performed on zeta(q) and M-S(alpha) by a lognormal model to compute the intermittency parameter. By contrast with PM10 which mainly depends on puffs of Saharan dust (synoptic-scale), O-3 is more intermittent due to variability of its local precursors. The results presented in this paper can help to better understand the mechanisms governing the dynamics of PM10 and O-3 in Caribbean islands context. (C) 2017 Elsevier Ltd. All rights reserved.