Martian Water Ice Clouds During the 2018 Global Dust Storm as Observed by the ACS‐MIR Channel Onboard the Trace Gas Orbiter

1. INTRODUCTIONThe Mars Science Laboratory (MSL) is located in Gale Crater (4.5&#176;S, 137.4&#176;E), and has been performing cloud observations for the entirety of its mission, since its landing in 2012 [eg. 1,2,3]. One such observation is the Phase Function Sky Survey (PFSS), developed by Cooper et al [3] and instituted in Mars Year (MY) 34 to determine the scattering phase function of Martian water-ice clouds. The clouds of interest form during the Aphelion Cloud Belt (ACB) season (Ls=50&#176;-150&#176;), a period of time during which there is an increase in the formation of water-ice clouds around the Martian equator [4]. The PFSS observation was also performed during the MY 35 ACB season and the current MY 36 ACB season.Following the MY 34 ACB season, Mars experienced a global dust storm which lasted from Ls~188&#176; to Ls~250&#176; of that Mars year [5]. Global dust storms are planet-encircling storms which occur every few Mars years and can significantly impact the atmosphere leading to increased dust aerosol sizes [6], an increase in middle atmosphere water vapour [7], and the formation of unseasonal water-ice clouds [8]. While the decrease in visibility during the global dust storm itself made cloud observation difficult, comparing the scattering phase function prior to and following the global dust storm can help to understand the long-term impacts of global dust storms on water-ice clouds.2. METHODSThe PFSS consists of 9 cloud movies of three frames each, taken using MSL&#8217;s navigation cameras, at a variety of pointings in order to observe a large range of scattering angles. The goal of the PFSS is to characterise the scattering properties of water-ice clouds and to determine ice crystal geometry.&#160; In each movie, clouds are identified using mean frame subtraction, and the phase function is computed using the formula derived by Cooper et al [3]. An average phase function can then be computed for the entirety of the ACB season.<img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.eda718c85da062913791261/sdaolpUECMynit/1202CSPE&app=m&a=0&c=67584351a5c2fde95856e0760f04bbf3&ct=x&pn=gnp.elif&d=1" alt="Figure 1 &#8211; Temporal Distribution of Phase Function Sky Survey Observations for Mars Years 34 and 35" width="800" height="681">Figure 1 shows the temporal distributions of PFSS observations taken during MYs 34 and 35. We aim to capture both morning and afternoon observations in order to study any diurnal variability in water-ice clouds.3. RESULTS AND DISCUSSIONThere were a total of 26 PFSS observations taken in MY 35 between Ls~50&#176;-160&#176;, evenly distributed between AM and PM observations. Typically, times further from local noon (i.e. earlier in the morning or later in the afternoon) show stronger cloud features, and run less risk of being obscured by the presence of the sun. In all movies in which clouds are detected, a phase function can be calculated, and an average phase function determined for the whole ACB season. &#160;Future work will look at the water-ice cloud scattering properties for the MY 36 ACB season, allowing us to get more information about the interannual variability of the ACB and to further constrain the ice crystal habit. The PFSS observations will not only assist in our understanding of the long-term atmospheric impacts of global dust storms but also add to a more complete image of time-varying water-ice cloud properties.

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The ExoMars Trace Gas Orbiter – First Martian Year in Orbit

10.5194/egusphere-egu2020-22228 ◽

2020 ◽

Author(s):

Håkan Svedhem ◽

Oleg Korablev ◽

Igor Mitrofanov ◽

Daniel Rodionov ◽

Nicholas Thomas ◽

...

Keyword(s):

Surface Science ◽

Dust Storm ◽

European Space Agency ◽

High Sensitivity ◽

Global Scale ◽

Trace Gas ◽

Full Potential ◽

Water Ice ◽

Surface Hydrogen ◽

Space Agency

The Trace Gas Orbiter, TGO, has in March 2020 concluded its first Martian year in its 400km, 74 degrees inclination, science orbit. It has been a highly successful year, starting with the rise, plateau and decay of the major Global Dust Storm in the summer of 2018. This has enabled interesting results to be derived on the water vapour distribution, dynamic behaviour and upward transport as a consequence of the dust storm. The characterisation of the minor species and trace gasses is continuing and a large number of profiles is produced every day. A dedicated search of methane has shown that there is no methane above an altitude of a few km, with an upper limit established at about 20 ppt (2&#8729;10-11). The solar occultation technique used by the spectrometers has definitely proven its strength, both for its high sensitivity and for its capability of making high resolution altitude profiles of the atmosphere. Climatological studies have been initiated and will become more important now that a full year has passed, even if the full potential will be visible only after a few Martian years of operation. The FREND instrument has characterised the hydrogen in the shallow sub-surface on a global scale at a spatial resolution much better than previous missions have been able. It has found areas at surprisingly low latitudes with significant amounts of sub-surface hydrogen, most likely in the form of water ice. The CaSSIS camera has made a high number of images over a large variety of targets, including the landing sites of the 2020 ESA and NASA rovers, Oxia Planum and the Jezero Crater. Stereo imaging has enabled topographic information and precise 3-D landscape synthesis.This presentation will summarise the highlights of the first Martian year and discuss planned activities for the near and medium term future.The ExoMars programme is a joint activity by the European Space Agency (ESA) and ROSCOSMOS, Russia. It consists of the ExoMars 2016 mission, launched 14 March 2016, with the Trace Gas Orbiter, TGO, and the Entry Descent and Landing Demonstrator, EDM, named Schiaparelli, and the ExoMars 2020 mission, to be launched in July/August 2020, carrying a Rover and a surface science platform to the surface of Mars.

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The ExoMars Trace Gas Orbiter – Progress and future studies

10.5194/egusphere-egu21-16216 ◽

2021 ◽

Author(s):

Håkan Svedhem ◽

AnnCarine Vandaele ◽

Oleg Korablev ◽

Igor Mitrofanov ◽

Nicolas Thomas

Keyword(s):

Surface Science ◽

Dust Storm ◽

European Space Agency ◽

Daily Basis ◽

Global Scale ◽

Seasonal Effects ◽

Trace Gas ◽

Full Potential ◽

Water Ice ◽

Space Agency

The Trace Gas Orbiter, TGO, is now well into its second Martian year of operations. The first year has been a highly successful Martian year, starting with the rise, plateau and decay of the major Global Dust Storm in the summer of 2018. This has enabled interesting results to be derived on the dynamic behaviour as a consequence of the dust storm. A significant observations is the strong upward transport of water vapour that has been found during the dust storm. HCl has been detected for the first time in the Martian atmosphere, and characterisations of the other minor species and trace gasses are continuing. A large numbers of profiles are being produced on a daily basis. The dedicated search of methane is continuing and still shows that there is no methane above an altitude of a few km, with an upper limit established at about 20 pptv (2&#8729;10-11).We now have a full Martian year of observations after the Global dust storm, and seasonal effects can now be studied under normal conditions. Climatological studies, benefitting from the 400km, 74 degrees inclination non-solar synchronous orbit, have been initiated, even if the full potential will be visible only after a few Martian years of operation. The FREND instrument has characterised the hydrogen in the shallow sub-surface on a global scale, at a spatial resolution much better than previous missions have been able to do. It has found areas at surprisingly low latitudes with significant amounts of sub-surface hydrogen, most likely in the form of water ice. The CaSSIS camera has made a well above 15,000 of images over a large variety of targets, including the landing sites of the 2020 NASA and 2022 ESA rovers, Jezero Crater and Oxia Planum. Stereo imaging has enabled topographic information and precise 3-D landscape synthesis.This presentation will summarise the highlights and recent results and discuss planned activities for the near and medium term future.The ExoMars programme is a joint activity by the European Space Agency (ESA) and ROSCOSMOS, Russia. It consists of the ExoMars 2016 mission, launched 14 March 2016, with the Trace Gas Orbiter, TGO, and the Entry Descent and Landing Demonstrator, EDM, named Schiaparelli, and the ExoMars 2022 mission, to be launched in September 2022, carrying a Rover and a surface science platform to the surface of Mars.

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Observations of the Martian atmosphere by NOMAD on ExoMars Trace Gas Orbiter

10.5194/egusphere-egu2020-8812 ◽

2020 ◽

Author(s):

Ann Carine Vandaele ◽

Arianna Piccialli ◽

Ian R. Thomas ◽

Frank Daerden ◽

Shohei Aoki ◽

...

Keyword(s):

Spectral Range ◽

Dust Storm ◽

Trace Gases ◽

Martian Atmosphere ◽

Trace Gas ◽

Ice Clouds ◽

Mars Atmosphere ◽

Solar Occultation ◽

Composition And Structure

The NOMAD (&#8220;Nadir and Occultation for MArs Discovery&#8221;) spectrometer suite on board the ExoMars Trace Gas Orbiter has been designed to investigate the composition of Mars' atmosphere, with a particular focus on trace gases, clouds and dust probing the ultraviolet and infrared regions covering large parts of the 0.2-4.3 &#181;m spectral range [1,2].Since its arrival at Mars in April 2018, NOMAD performed solar occultation, nadir and limb observations dedicated to the determination of the composition and structure of the atmosphere. Here we report on the different discoveries highlighted by the instrument: investigation of the 2018 Global dust storm and its impact on the water uplifting and escape, its impact on temperature increases within the atmosphere as inferred by GCM modeling and observations, the dust and ice clouds distribution during the event, ozone measurements, dayglow observations and in general advances in the analysis of the spectra recorded by the three channels of NOMAD.References[1] Vandaele, A.C., et al., 2015. Planet. Space Sci. 119, 233-249.[2] Vandaele et al., 2018. Space Sci. Rev., 214:80, doi.org/10.1007/s11214-11018-10517-11212.

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The ExoMars Trace Gas Orbiter - First Martian Year in Orbit

10.5194/epsc2020-802 ◽

2020 ◽

Author(s):

Håkan Svedhem ◽

Oleg Korablev ◽

Igor Mitrofanov ◽

Daniel Rodionov ◽

Nicolas Thomas ◽

...

Keyword(s):

Surface Science ◽

Dust Storm ◽

European Space Agency ◽

High Sensitivity ◽

Daily Basis ◽

Global Scale ◽

Trace Gas ◽

Full Potential ◽

Water Ice ◽

Space Agency

The Trace Gas Orbiter, TGO, concluded its first Martian year in orbit in March 2020. It has been a highly successful Martian year, starting with the rise, plateau and decay of the major Global Dust Storm in the summer of 2018. This has enabled interesting results to be derived on the dynamic behaviour as a consequence of the dust storm. One of the significant observations is a strong upward transport of water vapour that has been found during this time. Characterisations of the minor species and trace gasses are continuing and large numbers of profiles are being produced on a daily basis. A dedicated search of methane has shown that there is no methane above an altitude of a few km, with an upper limit established at about 20 pptv (2&#8729;10-11).The solar occultation technique applied by the spectrometers has definitely proven its strength, both for its high sensitivity and for its capability of making high-resolution altitude profiles of several parameters in the atmosphere. Climatological studies, benefitting from the 400km, 74 degrees inclination non-solar synchronous orbit, have been initiated and will become more important now that a full year has passed, even if the full potential will be visible only after a few Martian years of operation. The FREND instrument has characterised the hydrogen in the shallow sub-surface on a global scale, at a spatial resolution much better than previous missions have been able to do. It has found areas at surprisingly low latitudes with significant amounts of sub-surface hydrogen, most likely in the form of water ice. The CaSSIS camera has made a high number of images over a large variety of targets, including the landing sites of the 2020 NASA and 2022 ESA rovers, Oxia Planum and the Jezero Crater. Stereo imaging has enabled topographic information and precise 3-D landscape synthesis.This presentation will summarise the highlights of the first Martian year and discuss planned activities for the near and medium term future.The ExoMars programme is a joint activity by the European Space Agency (ESA) and ROSCOSMOS, Russia. It consists of the ExoMars 2016 mission, launched 14 March 2016, with the Trace Gas Orbiter, TGO, and the Entry Descent and Landing Demonstrator, EDM, named Schiaparelli, and the ExoMars 2020 mission, to be launched in July/August 2020, carrying a Rover and a surface science platform to the surface of Mars.

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Strong Variability of Martian Water Ice Clouds During Dust Storms Revealed From ExoMars Trace Gas Orbiter/NOMAD

Journal of Geophysical Research Planets ◽

10.1029/2019je006250 ◽

2020 ◽

Vol 125 (4) ◽

Author(s):

Giuliano Liuzzi ◽

Geronimo L. Villanueva ◽

Matteo M.J. Crismani ◽

Michael D. Smith ◽

Michael J. Mumma ◽

...

Keyword(s):

Dust Storms ◽

Trace Gas ◽

Ice Clouds ◽

Water Ice

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Ice clouds detection with NOMAD-LNO onboard ExoMars Trace Gas Orbiter

10.5194/egusphere-egu21-14775 ◽

2021 ◽

Author(s):

Luca Ruiz Lozano ◽

Özgür Karatekin ◽

Véronique Dehant ◽

Giancarlo Bellucci ◽

Fabrizio Oliva ◽

...

Keyword(s):

Trace Gas ◽

Storm Event ◽

Ice Clouds ◽

Seasonal Behavior ◽

Water Ice ◽

The United Kingdom ◽

Space Agency ◽

Dust Storm Event ◽

Italian Space Agency ◽

Ice Detection

This work takes advantage of the NOMAD spectrometer observations, on board the 2016 ExoMars Trace Gas Orbiter. ExoMars is an ESA-Roscosmos joint mission consisting of a rover and an orbiter (Trace Gas Orbiter - TGO). The Nadir and Occultation for Mars Discovery (NOMAD) is one of the four instruments on board TGO. The instrument is a suite of three spectrometers designed to observe the atmosphere and the surface of Mars in the UV, visible and IR. For this study, the Limb, Nadir and Occultation (LNO) channel, operating in the IR, is selected [1][2]. &#160;We focus on specific signatures in the [2.3 - 3.8 &#956;m] range of NOMAD-LNO in order to study the possible detection of clouds at these wavelengths in the infrared.For this study, we have selected the order 169 ([2611.8 nm - 2632.7 nm]) located in the vicinity of 2.7 &#181;m CO2/H2O ices absorption band. We search for the presence of ice clouds in MY 34 (LS = 150&#176; - 360&#176;) and MY 35 for observations with a solar zenith angle below 80 degrees.&#160; The detection method is adapted from Bellucci et al., 2019 [3] and L. Ruiz Lozano et al., 2020 [4]. &#160;The initial results indicate a number of detections in the Tharsis region consistent with the known &#8216;W&#8217; clouds [6][7].&#160; Finally, these results will be compared with the NOMAD-UVIS observations ([230 nm - 310 nm]) obtained at the same TGO orbits.Acknowledgements The NOMAD experiment is led by the Royal Belgian Institute for Space Aeronomy (IASB-BIRA), assisted by Co-PI teams from Spain (IAA-CSIC), Italy (INAF-IAPS), and the United Kingdom (Open University). This project acknowledges funding by the Belgian Science Policy Office (BELSPO), the Belgian Fonds de la Recherche Scientifique &#8211; FNRS under grant number 30442502 (ET_HOME) and the FRIA, with the financial and contractual coordination by the ESA Prodex Office (PEA 4000103401, 4000121493), by Spanish Ministry of Science and Innovation (MCIU) and by European funds under grants PGC2018-101836-B-I00 and ESP2017-87143-R (MINECO/FEDER), as well as by UK Space Agency through grants ST/R005761/1, ST/P001262/1, ST/R001405/1 and ST/R001405/1 and Italian Space Agency through grant 2018-2-HH.0.&#160;References [1] A.C. Vandaele et al., 2015. Optical and radiometric models of the NOMAD instrument part I: the UVIS channel. Optics Express, 23(23):30028&#8211;30042. [2] E. Neefs et al., 2015. NOMAD spectrometer on the ExoMars trace gas orbiter mission: part 1&#8212;design, manufacturing and testing of the infrared channels. Applied optics, 54(28):8494&#8211;8520. [3] G. Bellucci et al., 2019. TGO/NOMAD Nadir observations during the 2018 global dust storm event, EPSC-DPS 2019 [4] L. Ruiz Lozano et al., 2020. Use of TGO-NOMAD nadir observations for ice detection, EPSC Abstracts, Vol. 14, Virtual EPSC 2020, EPSC2020-748. [5] M. Vincendon, et al., 2011. New near&#8208;IR observations of mesospheric CO2 and H2O clouds on Mars, J. Geophys. Res., 116, E00J02, doi:10.1029/2011JE003827. [6] J. L. Benson, et al., 2003. The seasonal behavior of water ice clouds in the Tharsis and Valles Marineris regions of Mars: Mars Orbiter Camera Observations, Icarus, Volume 165, Issue 1, 2003, Pages 34-52, ISSN 0019-1035, https://doi.org/10.1016/S0019-1035(03)00175-1.

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