Chlorine-containing salts as water ice nucleating particles on Mars

Santiago-Materese, Delia; Iraci, L. T.; Clapham, Matthew E.; Chuang, P. Y.

doi:10.1016/j.icarus.2017.11.001

Cited by 6 publications

(5 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During a dust storm event, both of these forms of Cl may be lofted into the atmosphere, making chlorine readily available in the lower atmosphere at this time. Releasing gasphase chlorine from chloride salts may involve hydration of the chlorine salts, which has been shown to be effective in martian conditions (29). This can be followed by oxidation reactions and the release of radicals.…”

Section: Discussionmentioning

confidence: 99%

Transient HCl in the atmosphere of Mars

et al. 2021

View full text Add to dashboard Cite

A major quest in Mars’ exploration has been the hunt for atmospheric gases, potentially unveiling ongoing activity of geophysical or biological origin. Here, we report the first detection of a halogen gas, HCl, which could, in theory, originate from contemporary volcanic degassing or chlorine released from gas-solid reactions. Our detections made at ~3.2 to 3.8 μm with the Atmospheric Chemistry Suite and confirmed with Nadir and Occultation for Mars Discovery instruments onboard the ExoMars Trace Gas Orbiter, reveal widely distributed HCl in the 1- to 4-ppbv range, 20 times greater than previously reported upper limits. HCl increased during the 2018 global dust storm and declined soon after its end, pointing to the exchange between the dust and the atmosphere. Understanding the origin and variability of HCl shall constitute a major advance in our appraisal of martian geo- and photochemistry.

show abstract

Section: Discussionmentioning

confidence: 99%

Transient HCl in the atmosphere of Mars

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Laboratory studies have shown that such a pathway is viable (Sjostedt & Abbatt 2008), and also that Martian conditions are sufficient Article number, page 6 of 14 K.S. Olsen et al: Reappearance of HCl in the atmosphere of Mars to hydrate aerosols (Santiago-Materese et al 2018), which was the case during the MY 34 GDS (Fedorova et al 2020). Furthermore, nitrates have been identified on the surface of Mars and should make up a component of lofted dust (Stern et al 2017); in addition, the presence of nitrates should lead to acid formation (Smith et al 2014).…”

Section: Discussionmentioning

confidence: 99%

Seasonal reappearance of HCl in the atmosphere of Mars during the Mars year 35 dusty season

Olsen

Trokhimovskiy

Montabone

et al. 2021

A&A

View full text Add to dashboard Cite

Hydrogen chloride was discovered in the atmosphere of Mars for the first time during the global dust storm in Mars year (MY) 34 (July 2018) using the Atmospheric Chemistry Suite mid-infrared channel (ACS MIR) on the ExoMars Trace Gas Orbiter. The simultaneity of variations in dust and HCl, and a correlation between water vapour and HCl, led to the proposal of a novel surface-atmosphere coupling analogous to terrestrial HCl production in the troposphere from salt aerosols. After seasonal dust activity restarted in MY 35 (August 2020), we have been monitoring HCl activity to determine whether such a coupling was validated. Here we present a new technique for analysing the absorption features of trace gases close to the ACS MIR noise level and report that HCl mixing ratios are observed to rapidly increase in both hemispheres coincidentally with the onset of the MY 35 perihelion dust season. We present the temporal evolution of the vertical distribution of HCl (0.1–6 ppbv) and of dust activity in both hemispheres. We also report two observations of >2 ppbv HCl below 10 km in the northern hemisphere during the aphelion period.

show abstract

“…This pragmatic assumption was inspired by considering the available "ingredients" (dust particles, water vapor) that Mars disposes of. Still, the affinity between dust and ice germs, symbolized by the so-called contact parameter, first used in Mars cloud studies by Michelangeli et al (1993), has been a recurrent topic of dedicated laboratory and statistical analysis (Iraci et al, 2010;Määttänen & Douspis, 2014;Santiago-Materese et al, 2018;Trainer et al, 2009) without delivering a firm consensus on its actual value and dependence. There might be a variety of substrates apart from dust that are involved in the nucleation of water ice (such as chlorine salts; see Santiago-Materese et al, 2018), but climate models have conservatively obeyed the canonical assumption that only dust particles serve as nucleation seeds.…”

Section: Open Questionsmentioning

confidence: 99%

Clouds in the Martian Atmosphere

Määttänen

Montmessin

2021

Oxford Research Encyclopedia of Planetary Science

View full text Add to dashboard Cite

This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Planetary Science. Please check back later for the full article. Although resembling an extremely dry desert, planet Mars hosts clouds in its atmosphere. Every day somewhere on the planet a part of the tiny amount of water vapor held by the atmosphere can condense as ice crystals to form cirrus-type clouds. The existence of water ice clouds has been known for a long time, and they have been studied for decades, leading to the establishment of a well-known climatology and understanding of their formation and properties. Despite their thinness, they have a clear impact on the atmospheric temperatures, thus affecting the Martian climate. Another, more exotic type of clouds forms as well on Mars. The atmospheric temperatures can plunge to such frigid values that the major gaseous component of the atmosphere, CO2, condenses as ice crystals. These clouds form in the cold polar night where they also contribute to the formation of the CO2 ice polar cap, and also in the mesosphere at very high altitudes, near the edge of space, analogously to the noctilucent clouds on Earth. The mesospheric clouds are a fairly recent discovery and have put our understanding of the Martian atmosphere to a test. On Mars, cloud crystals form on ice nuclei, mostly provided by the omnipresent dust. Thus, the clouds link the three major climatic cycles: those of the two major volatiles, H2O and CO2; and that of dust, which is a major climatic agent itself.

show abstract

Chlorine-containing salts as water ice nucleating particles on Mars

Cited by 6 publications

References 58 publications

Transient HCl in the atmosphere of Mars

Transient HCl in the atmosphere of Mars

Seasonal reappearance of HCl in the atmosphere of Mars during the Mars year 35 dusty season

Clouds in the Martian Atmosphere

Contact Info

Product

Resources

About