Thermal tides during the 2001 Martian global‐scale dust storm

Guzewich, Scott D.; Wilson, R. J.; McConnochie, T. H.; Toigo, A. D.; Banfield, D.; Smith, M. D.

doi:10.1002/2013je004502

Cited by 47 publications

(60 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The air mass remains physically intact and circulates around the pole every sol at its fixed local time. This effect is related to the strong diurnal tide in the south polar lower atmosphere that was also observed during the Mars Year 25 GDE (Guzewich et al, ).…”

Section: Resultsmentioning

confidence: 76%

Diurnal Variations of Dust During the 2018 Global Dust Storm Observed by the Mars Climate Sounder

et al. 2020

View full text Add to dashboard Cite

We report observations by the Mars Climate Sounder showing strong diurnal variations in temperature and the vertical dust distribution during the 2018 (Mars Year 34) global dust event.The temperature field shows weak diurnal tidal activity at equatorial latitudes but a strong diurnal tide in middle to high latitudes with a maximum amplitude of 29 K in the lower atmosphere of the south polar region. The diurnal variability of dust is small in the equatorial region and increases toward higher latitudes. At middle and low latitudes, comparable dust amounts are found about 5-10 km higher in the atmosphere on the dayside than on the nightside. The dust reaches the highest altitudes in the late afternoon and is found at the lowest altitudes in the late night. In the southern high latitudes a persistent cold air mass with low dust content is identified on the nightside of the planet centered at 3-6 a.m. local time. The observed variations are well represented by model simulations with the Laboratoire de Météorologie Dynamique General Circulation Model. Comparisons between data and model results suggest that the diurnal variations in the dust are largely driven by the meridional circulation exhibiting diurnal tidal variations. The model results show that the compact air mass in the south polar region has a high potential vorticity, supporting its interpretation as a remnant of the southern polar vortex, which is forced toward the nightside of the planet due to the enhanced diurnal tide during the global dust event.Plain Language Summary One of the most distinctive features of the Martian atmosphere are global dust storms, one of which occurred in 2018. We report on observations of the vertical structure of atmospheric temperature and dust by the Mars Climate Sounder onboard Mars Reconnaissance Orbiter. Strong differences between day and night are found in both temperature and dust vertical structure. The strongest temperature variations are observed in the south polar atmosphere, with temperature differences up to 58 • C/136 • F between day and night. Comparable dust amounts are found 5-10 km (3-6 miles) higher in the atmosphere on the dayside than on the nightside at central and equatorial latitudes. In the southern polar region a persistent cold body of air with low dust is identified on the nightside of the planet. The observations are compared with the results from a global atmospheric computer model. The observed temperature and dust distribution and their variations over the Martian day are well represented by the model. The diurnal variations in the dust are largely driven by diurnal changes in the large-scale atmospheric circulation. The compact body of air in the south polar region is forced to the nightside by this altered circulation but does not dissipate for several months.

show abstract

Section: Resultsmentioning

confidence: 76%

Diurnal Variations of Dust During the 2018 Global Dust Storm Observed by the Mars Climate Sounder

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The opacities of atmospheric dust were based on Mars Global Surveyor Thermal Emission Spectrometer (TES) dust climatology (limb values averaged over ~3 Mars years) as described in Guzewich et al . []. Figure shows that the variation with season of this prescribed dust opacity is in good agreement with the variation of the column optical depth measured by the Mast Camera of MSL (note that the difference in actual magnitude is due to the different wavelengths here).…”

Section: Resultsmentioning

confidence: 99%

“…The modeled data were generated by mesoscale runs, performed with settings otherwise identical to those mentioned in Bridges et al [2014] except that the innermost nest had a resolution of~1.4 km in Gale Crater, in contrast to~4 km used by Bridges et al [2014]. The opacities of atmospheric dust were based on Mars Global Surveyor Thermal Emission Spectrometer (TES) dust climatology (limb values averaged over~3 Mars years) as described in Guzewich et al [2014]. Figure 14 shows that the variation with season of this prescribed dust opacity is in good agreement with the variation of the column optical depth measured by the Mast Camera of MSL (note that the difference in actual magnitude is due to the different wavelengths here).…”

Section: Annual Variation In Vortex Activitymentioning

confidence: 99%

Convective vortices and dust devils at the MSL landing site: Annual variability

et al. 2016

View full text Add to dashboard Cite

Two hundred fifty‐two transient drops in atmospheric pressure, likely caused by passing convective vortices, were detected by the Rover Environmental Monitoring Station instrument during the first Martian year of the Mars Science Laboratory (MSL) landed mission. These events resembled the vortex signatures detected by the previous Mars landers Pathfinder and Phoenix; however, the MSL observations contained fewer pressure drops greater than 1.5 Pa and none greater than 3.0 Pa. Apparently, these vortices were generally not lifting dust as only one probable dust devil has been observed visually by MSL. The obvious explanation for this is the smaller number of strong vortices with large central pressure drops since according to Arvidson et al. [] ample dust seems to be present on the surface. The annual variation in the number of detected convective vortices followed approximately the variation in Dust Devil Activity (DDA) predicted by the MarsWRF numerical climate model. This result does not prove, however, that the amount of dust lifted by dust devils would depend linearly on DDA, as is assumed in several numerical models of the Martian atmosphere, since dust devils are only the most intense fraction of all convective vortices on Mars, and the amount of dust that can be lifted by a dust devil depends on its central pressure drop. Sol‐to‐sol variations in the number of vortices were usually small. However, on 1 Martian solar day a sudden increase in vortex activity, related to a dust storm front, was detected.

show abstract

“…Major dust storms are associated with not only a large‐scale increase in dust opacity but also numerous changes in global circulation. Previous studies found pronounced atmospheric responses to major dust storms through intensified Hadley circulation [ Kass et al ., ] and modified thermal tides [ Leovy and Zurek , ; Guzewich et al ., ]. This paper shows that westward traveling wave is one of the signature changes associated with major dust storms.…”

Section: Summary and Discussionmentioning

confidence: 99%

“…Previous studies revealed a close connection between the strength of northern hemisphere eastward traveling waves (especially zonal wave number m = 3) and the occurrence of frontal/flushing dust storms which often led to major dust storms [ Wang et al ., ; Hinson et al ., ]. Previous studies also reported dramatic changes in the Hadley circulation and forced (thermal tides and stationary) waves following major dust storms [ Leovy and Zurek , ; Banfield et al ., ; Guzewich et al ., ; Kass et al ., ].…”

Section: Introductionmentioning

confidence: 99%

Major dust storms and westward traveling waves on Mars

Wang

2017

Geophysical Research Letters

View full text Add to dashboard Cite

Westward traveling waves are observed during major dust storm periods in northern fall and winter. The close correlation in timing makes westward traveling wave one of the signature responses of the Martian atmosphere to major dust storms. Westward traveling waves are dominated by zonal wave number m = 1 in the middle atmosphere and are typically characterized by long wave period. They are associated with significant temperature perturbations near the edge of the north polar vortex. Their wind signals extend to the low latitudes and the southern hemisphere. Their eddy momentum and heat fluxes exhibit complex patterns on a global scale in the middle atmosphere.

show abstract

Thermal tides during the 2001 Martian global‐scale dust storm

Cited by 47 publications

References 51 publications

Diurnal Variations of Dust During the 2018 Global Dust Storm Observed by the Mars Climate Sounder

Diurnal Variations of Dust During the 2018 Global Dust Storm Observed by the Mars Climate Sounder

Convective vortices and dust devils at the MSL landing site: Annual variability

Major dust storms and westward traveling waves on Mars

Contact Info

Product

Resources

About