Orbit-Spin Coupling Torques and Martian Dust Storm Activity in MY34 and MY 35

Abstract Dust storms, observed in all seasons, are among the most momentous Mars atmosphere activities. The Entry-Descent-Landing (EDL) activity of a Martian landing mission is influenced by local atmospheric conditions, especially the dust storm activity probability. It is of great significance to know well the dust storm situation that China's first Mars mission (Tianwen-1) may encounter in EDL season in the Chryse area, one of the tentative landing areas. Firstly, based on four Martian years’ Mars Orbiter Camera (MOC) Mars Daily Global Maps (MDGMs), 1172 dust storms were identified within Chryse’s 1600 km radius ring with their shape parameters extracted, including center, range and area. Secondly, the daily mean dust storm probability was calculated binned by 1° of solar longitude in the Chryse area during EDL season. Dust storm activity frequency was closely interrelated with the seasonal ebb and flow of the arctic polar ice cap, consequently, most of dust storms occurring in either the cap’s grow or the recession. The dust storm activity in the Chryse area mainly came from the northern polar cap region, Acidalia and Chryse, with some contribution from the southern hemisphere (Argyre and Bosprous) northward. Thirdly, we divided the Chryse area into many square grids of 0.5° and computed the average occurrence probability of dust storm in each grid during EDL season. The dust storm activity probability in space was also in-homogeneous, low in the west and south but high in the east and north, which was mainly affected by three factors: topography, the origin and the path of dust storm sequence. Based on Empirical orthogonal function (EOF) analysis, of the storms in the Chryse area we’ve discovered, 40.5% are cap-edge storms in the northern hemisphere and 17.5% are textured dust storms. Finally, according to the temporal and spatial probability of dust storm activity in the Chryse area during EDL season, we held that the preferred landing time of the Tianwen-1 mission in 2021 was in Ls=18°-65° and three preferred landing areas were selected with low dust storm probability.

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An Observational Overview of Dusty Deep Convection in Martian Dust Storms

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-19-0042.1 ◽

2019 ◽

Vol 76 (11) ◽

pp. 3299-3326 ◽

Cited By ~ 6

Author(s):

Nicholas G. Heavens ◽

David M. Kass ◽

James H. Shirley ◽

Sylvain Piqueux ◽

Bruce A. Cantor

Keyword(s):

Dust Storm ◽

Large Scale ◽

Middle Atmosphere ◽

Deep Convection ◽

High Surface ◽

Dust Storms ◽

Radiative Heating ◽

Storm Activity ◽

Mesoscale Circulations ◽

Convective Structures

Abstract Deep convection, as used in meteorology, refers to the rapid ascent of air parcels in Earth’s troposphere driven by the buoyancy generated by phase change in water. Deep convection undergirds some of Earth’s most important and violent weather phenomena and is responsible for many aspects of the observed distribution of energy, momentum, and constituents (particularly water) in Earth’s atmosphere. Deep convection driven by buoyancy generated by the radiative heating of atmospheric dust may be similarly important in the atmosphere of Mars but lacks a systematic description. Here we propose a comprehensive framework for this phenomenon of dusty deep convection (DDC) that is supported by energetic calculations and observations of the vertical dust distribution and exemplary dusty deep convective structures within local, regional, and global dust storm activity. In this framework, DDC is distinct from a spectrum of weaker dusty convective activity because DDC originates from preexisting or concurrently forming mesoscale circulations that generate high surface dust fluxes, oppose large-scale horizontal advective–diffusive processes, and are thus able to maintain higher dust concentrations than typically simulated. DDC takes two distinctive forms. Mesoscale circulations that form near Mars’s highest volcanoes in dust storms of all scales can transport dust to the base of the upper atmosphere in as little as 2 h. In the second distinctive form, mesoscale circulations at low elevations within regional and global dust storm activity generate freely convecting streamers of dust that are sheared into the middle atmosphere over the diurnal cycle.

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Quantitative estimation of provenance contributions to loess deposits in Eastern China and implication for paleo-dust storm activity

Geomorphology ◽

10.1016/j.geomorph.2020.107489 ◽

2021 ◽

Vol 373 ◽

pp. 107489

Author(s):

Chao Wu ◽

Xiangmin Zheng ◽

Limin Zhou ◽

Shaofang Ren ◽

Peng Qian

Keyword(s):

Dust Storm ◽

Quantitative Estimation ◽

Eastern China ◽

Storm Activity ◽

Loess Deposits

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Dust storm activity over the Tibetan Plateau recorded by a shallow ice core from the north slope of Mt. Qomolangma (Everest), Tibet-Himal region

Geophysical Research Letters ◽

10.1029/2007gl030853 ◽

2007 ◽

Vol 34 (17) ◽

Cited By ~ 27

Author(s):

Jianzhong Xu ◽

Shugui Hou ◽

Dahe Qin ◽

Shichang Kang ◽

Jiawen Ren ◽

...

Keyword(s):

Tibetan Plateau ◽

Dust Storm ◽

Ice Core ◽

North Slope ◽

The Tibetan Plateau ◽

Storm Activity ◽

The North

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Textured Dust Storm Activity in Northeast Amazonis–Southwest Arcadia, Mars: Phenomenology and Dynamical Interpretation

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-16-0211.1 ◽

2017 ◽

Vol 74 (4) ◽

pp. 1011-1037 ◽

Cited By ~ 7

Author(s):

N. G. Heavens

Keyword(s):

Dust Storm ◽

Deep Convection ◽

Dust Storms ◽

Limited Area ◽

Mars Global Surveyor ◽

Storm Activity ◽

Structure And Dynamics ◽

Local Dust ◽

Visible Imagery ◽

Meteorological Phenomenon

Abstract Dust storms are Mars’s most notable meteorological phenomenon, but many aspects of their structure and dynamics remain mysterious. The cloud-top appearance of dust storms in visible imagery varies on a continuum between diffuse/hazy and textured. Textured storms contain cellular structure and/or banding, which is thought to indicate active lifting within the storm. Some textured dust storms may contain the deep convection that generates the detached dust layers observed high in Mars’s atmosphere. This study focuses on textured local dust storms in a limited area within Northeast (NE) Amazonis and Southwest (SW) Arcadia Planitiae (25°–40°N, 155°–165°W) using collocated observations by instruments on board the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) satellites. In northern fall and winter, this area frequently experiences dust storms with a previously unreported ruffled texture that resembles wide, mixed-layer rolls in Earth’s atmosphere, a resemblance that is supported by high-resolution active sounding and passive radiometry in both the near- and thermal infrared. These storms are mostly confined within the atmospheric boundary layer and are rarely sources of detached dust layers. The climatology and structure of these storms are thus consistent with an underlying driver of cold-air-advection events related to the passage of strong baroclinic waves. While the properties of the studied region may be ideal for detecting these structures and processes, the dynamics here are likely relevant to dust storm activity elsewhere on Mars.

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