Author(s)

HELI A. ARREGOCÉS, ROBERTO ROJANO, GLORIA RESTREPO

Abstract

Given that El NiÑo Southern Oscillation (ENSO) phenomena had significant environmental impacts in 2015–2016, this study presents an exploratory analysis of PM₁₀ variability in open-pit mining areas in northern Colombia. PM₁₀ and meteorological variables were measured at three locations, and analyses were performed. The results obtained showed that ENSO plays an important role in the temporal distribution of daily precipitation, and its occurrence resulted in an 8.3% decrease in annual average precipitation within the period of February 2015–May 2016. However, it had no significant effect on temperature, relative humidity, and wind speed within the study period. Further, the annual mean PM₁₀ concentration corresponding to all the stations considered in this study between 2014 and 2017 was 34 µg/m³ (95% CI, 33–35 µg/m³), and the standard deviation was ± 11.59 µg/m³. The individual arithmetic means of PM₁₀ concentrations at the different stations were 1.11–2.07 times the WHO air quality guidelines for PM₁₀ but did not exceed the maximum level permissible specified by the Colombian norm. Furthermore, the average PM₁₀ concentrations in all the samples corresponding to the El NiÑo classified Oceanic NiÑo Index (ONI) phase (37.14 µg/m³; CI95% 36.06–38.22 µg/m³) were numerically higher than those corresponding to the neutral classified ONI phase (32.54 µg/m³; CI95% 31.82–33.27 µg/m³), and the correlation coefficients between PM₁₀ and meteorological parameters were found to be relatively low.

Keywords

PM₁₀, ENSO, ONI, variability, air quality