Photo-enhanced uptake of SO₂ on Icelandic volcanic dusts

Abstract

Iceland is the largest volcanic dust (v-dust) desert on Earth, with an estimated area of 22,000 km2. In addition, Iceland is one of the most active aeolian areas in the...

Heterogeneous Physical Chemistry in the Atmospheres of Earth, Mars, and Venus: Perspectives for Rocky Exoplanets

“…Finally, the activation of the surface of mineral dust by irradiation with solar UV photons and/or the photochemistry of adsorbed surface species are important processes that can increase the reactivity by several orders of magnitude. This is observed during the uptake of SO 2 by volcanic dust 31 and interestingly during the photoreduction of CO 2 to CO on mineral dust. 38 These processes are strongly impacted by environmental factors, and their consequences for the budgets of chemical species have to be carefully assessed.…”

“…It is necessary to study these systems in detail to improve the modeling of CO 2 and CH 4 budgets and also of species like SO 2 that are responsible for the formation of sulfates and sulfites at the surface of dust grains. 30,31 It has been shown recently that initial SO 2 atmospheric lifetime is controlled by heterogeneous reactivity with ash rather than by reactivity with •OH radicals as commonly assumed, reinforcing the importance of such phenomena. 32 Volcanic dust and the species formed at their surface can be transported by winds over thousands of kilometers 33 before they settle on the ground or into the ocean, where they may represent a source of bioavailable metals and sulfur.…”

Unraveling the Uptake of Glyoxal on a Diversity of Natural Dusts and Surrogates: Linking Dust Composition to Glyoxal Uptake and Estimation of Atmospheric Lifetimes

“…The Gly uptake on mineral surfaces was studied using a Knudsen flow reactor (KFR), under fixed conditions of 70 ppb of Gly as inlet concentration, and T = 295 K. All measurements were performed under dry conditions, aiming to deconvolute the impact of elemental composition on the Gly uptake on natural dusts and to obtain the CAR. As discussed in the recent study of Urupina et al 39 and Zeineddine et al, 38 the presence of atmospheric humidity may mask trends linking the composition and uptake efficiency of trace gases.…”

“…In addition, the chemical composition of mineral dust is strongly dependent on its origin. ,,, Journet et al have provided a thorough mineralogical map with the chemical composition in the clay and silt fractions of dust on a global scale. However, to date, there are limited studies attempting to correlate the chemical composition of mineral dust with the specific uptake quantity or the kinetics (i.e., uptake coefficient, γ) of pollutants. − Indeed, in most of the literature studies where the aging of mineral particles was investigated, authors used either mineral proxies or a limited number of dust samples. , Possible correlations of mineral dust chemical composition, e.g., elemental composition, with pollutant uptakes can reveal important information about the contribution of specific elements to atmospheric reactivity and aging of dusts. Elements such as Al and Si, are characteristic of the Earth’s crust material, abundant in mineral dusts, and thus they are used as markers to deconvolute the presence of mineral dust in PM2.5 or PM10 aerosols .…”