Air quality in the Galapagos Islands: A baseline view from remote sensing and in situ measurements

Abstract

A characterization of ambient air levels of PM2.5, O3, SO2, NO2 and CO in the Galapagos Islands of Ecuador is presented from in situ and remote sensing observations. PM2.5 was derived from aerosol optical depth (AOD; AERONET) measured at the Universidad San Francisco de Quito, Galapagos Campus (2017–2019). Boundary layer (BL) ozone was obtained from Southern Hemisphere Additional Ozonesondes (SHADOZ) profiles (1998–2016). Background SO2 and pollution events during volcanic eruptions (2005–2018) were estimated from Ozone Monitoring Instrument (OMI) total column measurements through a well‐mixed volume approach. Similarly, ambient NO2 was estimated from OMI data (2012–2019). CO was obtained from Measurement Of Pollution In The Troposphere (MOPITT) observations (2012–2017). The study was complemented using Modern‐Era Retrospective Analysis for Research and Applications (MERRA‐2) reanalysis products and backward trajectory model runs. From the results, baseline levels of the analysed species (PM2.5 = 3.8 μg·m−3, O3 = 17 ppbv, SO2 = 3.6 ppbv, CO = 80 ppbv, NO2 in populated islands = 23 pptv as one year averages) are comparable with other pristine regions, but some factors can cause increased concentrations. First, high tourism seasons (February–April and July–September) raise background PM2.5, NO2 and CO. Furthermore, signals in July–September can be augmented by transport from biomass‐burning regions in the Amazon. This latter factor episodically causes ozone to increase up to 45–75 ppbv (1 hr mean). Lastly, volcanic eruptions raise SO2 up to almost 700 ppbv (24 hr mean) and increase PM2.5 to 29.5 μg·m−3 (1 hr mean). The present study provides for the first time baseline levels of air contaminants in the Galapagos, and identifies specific sources whose effect in time is necessary to monitor given global conditions of vulnerable environmental quality.

Scientific Research in Ecuador: A Bibliometric Analysis

“…Other authors have studied its forests and their diversity [154], freshwater ecosystems [155], as well as the discovery of new species [156][157][158][159][160][161][162][163]. Due to the importance of the Galapagos Islands, water security and water quality have been studied [164][165][166], the impact on fishery resources [167,168], damage caused by plastic waste [169], the effects on the soils of complex agrosystems [170] and air quality [171].…”

Water Quality from Natural Sources for Sustainable Agricultural Development Strategies: Galapagos, Ecuador

“…This phase considered planning irrigation water quality monitoring sites concerning natural sources. For this, we analysed base information on geology [56,72,73] and previous water quality studies [41,47,74,75]; a geodatabase (administrative boundaries, urban and rural structures, hydrography, farming areas, and the location of water structures) provided by government entities of the Galapagos Islands (CGREG, Ministry of Agriculture and Livestock (MAG, by its acronym in Spanish), Municipality of Santa Cruz and Municipal Public Company of Drinking Water and Sewage of Santa Cruz E.P. (EP-MAPASC, by its acronym in Spanish)); and inventories of water sources provided by the Rural Research Centre (CIR, by its acronym in Spanish) of the ESPOL Polytechnic University (Guayaquil, Ecuador), to identify and geographically locate the natural water sources existing on each island.…”

Changes in South American Surface Ozone Trends: Exploring the Influences of Precursors and Extreme Events

“…Monitoring has also been implemented through the Global Atmospheric Watch (GAW) program at remote locations, which allows studying changes in the chemical composition at high altitude sites (e.g., Tololo and Chacaltaya at 2,200 and 5,500 m a.s.l., respectively) and at pristine locations such as Patagonia (Ushuaia) and Galapagos (Anet et al, 2017;Cazorla and Herrera, 2020). Background monitoring stations are essential for interpreting the feedback between the atmospheric composition and the intensification of extreme weather events as well as for studying changes in transport patterns that could favor stratospheretroposphere exchange (STE) in the extratropics (Lu et al, 2019;Cooper et al, 2020).…”