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Dust aerosols can influence climate change, the ecological environment, human health, etc. and are one of the most important factors causing global change. The specific contributions of dust events, gusts, and dust devils to dust emission remain unclear in many regions. In this study, we quantified dust emissions generated by dust events, gusts, and dust devils in the center of the Taklimakan Desert of northwestern China and investigated their respective contributions to atmospheric dust aerosols. The results illustrated that monthly dust emissions and the dust emission time for dust events, gusts, and dust devils peaked in July, August, and June, respectively, and the average monthly contributions to dust emissions were 48.2, 10.6, and 41.2% and those to emission time were 60.5, 25.5, and 14.0%, respectively. Although the dust emissions for the dust event were comparable to the sum of gusts and dust devils, the average value of AOD corresponding to the dust event was roughly 2.5 times higher than that of a non-dust day. The results presented in this study not only highlight the undeniable contribution of gusts and dust devils to dust emissions but also indicate that the specific contributions to atmospheric dust aerosols from gusts and dust devils remain uncertain.

The pioneering contribution of G.S. Golitsyn to the theory of similarity of the circulation of planetary atmospheres; the energetics and statistics of tropical and polar hurricanes, extratropical cyclones, and anticyclones; and the energetics of tornadoes are briefly described. In addition, some issues of the energetics and statistics of dust devils on Earth and Mars are considered.

In this study we report about the first in‐situ analysis of terrestrial dust devil tracks (DDTs) observed in the Turpan depression desert in northwestern China. Passages of active dust devils remove a thin layer of fine grained material (< ∼63 μm), cleaning the upper surface of coarse sands (0.5–1 mm). This erosional process changes the photometric properties of the upper surface causing the albedo differences within the track to the surroundings. Measurements imply that a removal of an equivalent layer thickness of ∼2 μm is sufficient to form the dark dust devil tracks. Our terrestrial results are in agreement with the mechanism proposed by Greeley et al. (2005) for the formation of DDTs on Mars.

Strong winds associated with dust devils can induce locally large heat fluxes from the surface, and resulting enhanced buoyancy may further intensify the dust devils. This positive wind—surface-heat-flux feedback is studied using a large-eddy simulation of a convective boundary layer. A comparison of the results with and without the feedback process for the same environment demonstrates the significance of the feedback process for simulated dust devils.

We report on field observations in January 2009 (austral summer) of atmospheric dust devils in the northern part of the Atacama Desert in South America (≈20◦S). An extremely high level of dust-devil activity over the study site has been observed, dependent on local meteorological conditions. We found a high correlation between the dust-devil frequency of occurrence and the Obukhov length scale, L, calculated from meteorological gradient measurements, with a clear tendency for this frequency to increase with decreasing −L. The upper threshold values of −L ≈ 20-30 m, and the 2-m mean wind speed, V ₂ ≈ 8m s⁻¹, for dust-devil occurrence have been found, but the minimal V ₂ threshold was not observed. Parallel routine meteorological measurements enabled us to calculate the main constituents of the surface energy balance, to obtain direct estimates of the surface albedo (α ≈ 0.21 at the solar noon) and to summarize the local conditions.

The atmosphere of Mars is thin, although rich in dust aerosols, and covers a dry surface. As such, Mars provides an opportunity to expand our knowledge of atmospheres beyond that attainable from the atmosphere of the Earth. The InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) lander is measuring Mars’s atmosphere with unprecedented continuity, accuracy and sampling frequency. Here we show that InSight unveils new atmospheric phenomena at Mars, especially in the higher-frequency range, and extends our understanding of Mars’s meteorology at all scales. InSight is uniquely sensitive to large-scale and regional weather and obtained detailed in situ coverage of a regional dust storm on Mars. Images have enabled high-altitude wind speeds to be measured and revealed airglow—faint emissions produced by photochemical reactions—in the middle atmosphere. InSight observations show a paradox of aeolian science on Mars: despite having the largest recorded Martian vortex activity and dust-devil tracks close to the lander, no visible dust devils have been seen. Meteorological measurements have produced a catalogue of atmospheric gravity waves, which included bores (soliton-like waves). From these measurements, we have discovered Martian infrasound and unexpected similarities between atmospheric turbulence on Earth and Mars. We suggest that the observations of Mars’s atmosphere by InSight will be key for prediction capabilities and future exploration.The InSight lander has expanded our knowledge of the atmosphere of Mars by observing various phenomena, including airglow, bores, infrasound and Earth-like turbulence.

We quantify the effect of dust accumulation at Jezero crater by means of a Dust Correction Factor (DCF) for the solar radiation measured by the photodiodes of the Radiation and Dust Sensor of the Mars 2020 mission. After one Mars Year, dust on the photodiode surface attenuated 25%–30% of the incoming solar radiation. The DCF did not decrease monotonically; we use a model to reproduce its evolution and to derive dust deposition and lifting rates, showing that dust removal is 9 times larger at Jezero crater than at InSight's location in western Elysium Planitia. The model fit obtained using observed opacities is further improved when fed with dust sedimentation rates simulated by a GCM that considers a particle size distrtibution. Projections show seasonal net dust removal, being encouraging for the long‐term survival of solar‐powered missions to Jezero or similarly active dust lifting regions. Plain Language Summary Dust is ubiquitous in the Martian atmosphere, accumulating on both natural and artificial surfaces. Dust particularly affects the performance and lifetime of missions: the termination of InSight and MER‐B operations are recent examples. Dust accumulation shows a seasonal behavior, and attenuated 25%–30% of the incoming solar radiation on Perseverance after the first Mars Year of the mission. Dust removal is almost 10 times larger than at InSight's location: projections indicate that surfaces at Jezero will be periodically partially cleaned. The estimations of the effect of the accumulated dust as a function of time are encouraging for solar‐powered missions to regions with similar amounts of dust lifting, which might be determined from orbital data on where dust storms originate, dust devils or their tracks are found, or seasonal albedo changes are noted. In addition, the quantification of the effect of accumulated enables future studies requiring more accurate knowledge of incoming solar radiation at the surface. Key Points We present the evolution of dust accumulation at Jezero crater for more than one Mars Year We derive dust deposition and removal rates: removal is 9 times more efficient than at the InSight location in western Elysium Planitia Projections show that surfaces at Jezero will experience seasonal net dust removal, encouraging solar‐powered missions

Spirit began operations in Gusev Crater in January 2004 and has returned data on three seasons of dust devil (DD) activity. Total DDs observed were 533 in season one, 101 in season two, and 127 in season three. Their general characteristics are the same within factors of 2 among the seasons, with median diameters of 19 m in season one, 24 m in season two, and 39 m in season three, and dust flux values for individual vortices ranging from 4.0 × 10−9 to 4.6 × 10−4 kg m−2 s−1 in season one, 5.2 × 10−7 to 6.2 × 10−5 kg m−2 s−1 in season two, and 1.5 × 10−7 to 1.6 × 10−4 kg m−2 s−1 in season three. All three seasons were initiated with the onset of southern Martian spring within 14 sols of the same Ls (181°) and their frequency increased to the period corresponding to late southern spring. The occurrences decreased monotonically in seasons one and three but apparently ended abruptly in season two when a large dust storm occurred; although the dusty atmosphere might have precluded the detection of active DDs, the abrupt cessation could result from conditions such as thermal stability of the atmosphere due to the presence of dust which could halt DD formation. Dust devils can contribute significant quantities of dust to the atmosphere, although it is unclear as to whether this dust stays locally or is injected into higher‐altitude winds and is distributed elsewhere. In the three DD seasons observed through Spirit, DDs in Gusev Crater injected a minimum average of ∼18 × 106 kg of material into the atmosphere each season.

The diurnal cycle of dust aerosols on Mars is studied by analyzing lidar observations at the Phoenix landing site under cloud‐ and fog‐free conditions and in the absence of elevated, long‐range transported dust layers. There is a pronounced diurnal cycle in the dust‐layer height with minimum heights of 4–6 km occurring between 11:00 and 17:00 local time. The ratio of the aerosol optical depth (AOD) within the lowermost 2 km to the total AOD reaches peak values at the same time. This can be explained by local dust emissions driven by the diurnal cycle of heating and cooling in the boundary layer. Analysis of wind and pressure measurements show that the gustiness of surface winds and the frequency of convective vortices undergo diurnal variations resembling those of AOD, indicating that these processes are the main drivers for local dust emissions. Plain Language Summary Dust particles suspended in air are important for the radiative energy budget of Mars. By interacting with solar radiation, these aerosols impact the temperature, dynamics, and composition of the atmosphere, as well as the surface temperature of Mars. Dust aerosols are produced by wind‐lifting processes ranging from small‐scale eddies to planetary‐scale dust storms, resulting in spatially and temporally varying concentrations. Here the focus is on the diurnal cycle of dust emissions as observed by the Phoenix lander. By jointly analyzing light‐scattering observations by a lidar instrument and measurements of wind speed and air pressure, one can correlate the concentration of aerosols in air in proximity to the ground to meteorological processes. The results reveal distinct maxima in aerosol loads, the intensity of wind gusts, and the frequency of dust devils around local noon and early afternoon, and corresponding minima around midnight. This indicates that gustiness and dust devils, both fueled by solar heating during the day, are among the main causes for local dust emissions. During daytime the aerosols are concentrated at altitudes of 4–6 km. This can provide us with an indication for the degree of vertical mixing in the planetary boundary layer of Mars. Key Points Diurnal variation of local dust emissions, wind gustiness, and convective vortices are analyzed for the entire Phoenix mission Peak values are observed in early afternoon, indicating that gustiness and convective vortices are main drivers for local dust emissions Typical dust‐layer heights in early afternoon are 4–6 km, consistent with typical boundary‐layer heights

Atmospheric mineral dust has recently become an important research field in Earth system science because of its impacts on radiation, clouds, atmospheric dynamics and chemistry, air quality, and biogeochemical cycles. Studying and modeling dust emission and transport over the world's largest source region, the Sahara, is particularly challenging because of the complex meteorology and a very sparse observational network. Recent advances in satellite retrievals together with ground‐ and aircraft‐based field campaigns have fostered our understanding of the spatiotemporal variability of the dust aerosol and its atmospheric drivers. We now have a more complete picture of the key processes in the atmosphere associated with dust emission. These cover a range of scales from (1) synoptic scale cyclones in the northern sector of the Sahara, harmattan surges and African easterly waves, through (2) low‐level jets and cold pools of mesoscale convective systems (particularly over the Sahel), to (3) microscale dust devils and dusty plumes, each with its own pronounced diurnal and seasonal characteristics. This paper summarizes recent progress on monitoring and analyzing the dust distribution over the Sahara and discusses implications for numerical modeling. Among the key challenges for the future are a better quantification of the relative importance of single processes and a more realistic representation of the effects of the smaller‐scale meteorological features in dust models. In particular, moist convection has been recognized as a major limitation to our understanding because of the inability of satellites to observe dust under clouds and the difficulties of numerical models to capture convective organization. Key Points Atmospheric mineral dust is an important research field in Earth system science New satellite and field data reveal dust variability and atmospheric drivers Representing small‐scale meteorological processes is a key challenge for models