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We describe the model‐independent analysis technique of Mars Science Laboratory (MSL) pressure and Mars Climate Sounder (MCS) data in de la Torre Juárez et al. (2019, https://doi.org/10.22541/essoar.169945479.90436599/v1) that compared multiple years of surface pressures on Gale before, during, and after the Global Dust Storm of Mars Year 34. The analysis found (a) representative pressure scale heights over Gale; (b) that the storm was followed by a pressure deficit at Gale; (c) the following C storms did not eliminate the deficit; (d) changes in the duration of the polar caps condensation seasons, with an early start of the North Polar (NP) ice cap growing season the year before the Great Dust Storm (GDS) and a late signature of the end of the expansion season thereafter, changes consistent with a larger growth phase of the NP cap; (e) MCS observed a larger than usual NP cap; and (f) cold temperature anomalies over the NP and warm over the Southern Pole after the storm. We also show that the analysis of observed MSL pressure data alone filters out effects on the pressure signal that are attributable to dynamical and orographic processes in a recent model analysis that makes similar interpretations as our 2019 study. One additional Mars year of observations is included to eliminate early concerns about sensor drifts. Noting that a similar NP anomaly was observed with MCS data after the last early GDS in MY25, and not the later GDS of MY27, the results suggest a possible unique effect of early GDSs. In 2018, Mars Year 34, Mars experienced a dust storm that encircled the whole planet and darkened its skies more than most storms in the recent past. Already in 2019 an analysis reported surface pressures below the climatological values observed over the previous 3 years in Gale Crater. The pressure deficit persisted into Mars Year 35 long after the end of the storm and dust over Gale had returned to levels from previous years. The storm coincided with a longer duration of the condensation season of the North Polar ice cap and a subsequent increase in its maximum amount of ice volume. We perform here a full analysis of five Mars Years of data showing how the duration of the polar caps sublimation/condensation seasons changed around the time of the storm, that the extension of the polar caps changed, and that the atmosphere above the North Pole was slightly colder than in years before the storm. A technique to measure representative pressure scale heights at Gale enables tracking signatures of changes in the polar ice capsREMS surface pressure with Mars Climate Sounder observations are used to describe the polar processes after the great storm of Mars Year 34Multiannual pressure data show a short Southern Polar Cap growth season before the storm followed by a long Northern Polar Cap growth season A technique to measure representative pressure scale heights at Gale enables tracking signatures of changes in the polar ice caps REMS surface pressure with Mars Climate Sounder observations are used to describe the polar processes after the great storm of Mars Year 34 Multiannual pressure data show a short Southern Polar Cap growth season before the storm followed by a long Northern Polar Cap growth season more...

Diurnal solar radiation causes global oscillations in pressure, temperature, and wind fields, known as atmospheric tides, which are further modified by topography, surface properties, and atmospheric dust loading. Hence, the tides are a combination of sun‐synchronous and non sun‐synchronous tides that propagate around the planet both eastward and westward. In the Martian tropics, atmospheric tides dominate daily pressure variations on the surface. Therefore, surface observing platforms are extremely useful for detailed analysis of atmospheric tides. In this investigation, we analyze diurnal and semi‐diurnal components of atmospheric surface pressure measured by the simultaneously operating InSight and Mars Science Laboratory (MSL) payloads. We utilize observations of the time period from Martian year (MY) 34 solar longitude 296° to MY 36 solar longitude 53°. The diurnal tide average amplitude is 17 Pa with an average phase of 03:39 local true solar time (LTST), while the semi‐diurnal tide average amplitude and phase are 7 Pa and 09:34 LTST for the InSight. The corresponding values for the MSL are 33 Pa with 04:25 LTST for the diurnal and 10 Pa with 09:36 LTST for the semi‐diurnal component. Thermo‐topographic lateral hydrostatic adjustment flow generated by topography causes the higher diurnal amplitude observed by MSL. Both platforms observe a similar response between these harmonic components and dust loading. Furthermore, amplitudes obtained from a Mars Climate Database mimic the observations well. Our study provides for the first time a comparison of atmospheric tides at two simultaneously observing tropical surface platforms for more than 1 MY. The Curiosity rover landed on Mars in August 2012 and has been observing meteorological variables ever since. The next surface observing station, the InSight lander, landed in the equatorial region of Mars in November 2018, relatively close to Curiosity. Unfortunately, InSight reached end of its mission on 15 December 2022, but fortunately they observed Martian atmosphere simultaneously for more than one Martian year. Atmospheric pressure is a very important meteorological variable, since many weather phenomena are associated with changes in surface pressure. Here, we use pressure observations from these two weather stations to determine Martian equatorial atmospheric tides and compare them with model simulations. They are forced by solar radiation and additionally modified by topography, surface properties, and atmospheric dust. They propagate around the planet in periods that are integer fractions of a Martian day. The two strongest components, diurnal and semi‐diurnal, with periods of 24 and 12 hr, are studied here. The results show the effect of atmospheric dust loading and the location on these components. We find a similar response between these components and atmospheric dust loading on both platforms and a higher amplitude of the diurnal tide at the Curiosity location due to differences in topography. We analyze diurnal and semi‐diurnal atmospheric tidal components from simultaneous InSight and Mars Science Laboratory (MSL) observationsWe find higher amplitude of the diurnal harmonic component at MSL location due to differences in topographyWe find a similar response between the harmonic components and atmospheric dust loading on both platforms We analyze diurnal and semi‐diurnal atmospheric tidal components from simultaneous InSight and Mars Science Laboratory (MSL) observations We find higher amplitude of the diurnal harmonic component at MSL location due to differences in topography We find a similar response between the harmonic components and atmospheric dust loading on both platforms more...

Surface pressure measurements on Mars have revealed a wide variety of atmospheric phenomena. The Mars Science Laboratory Rover Environmental Monitoring Station pressure sensor data set is now the longest duration record of surface pressure on Mars. We use the first 2580 Martian sols, nearly 4 Mars years, of measurements to identify atmospheric pressure waves with periods of tens of minutes to hours using wavelet analysis on residual pressure after the tidal harmonics are removed. We find these waves have a clear diurnal cycle with strongest activity in the early morning and late evening and a seasonal cycle with the strongest waves in the second half of the martian year (Ls= 180–360°). The strongest such waves of the entire mission occurred during the Mars Year 34 global dust storm. Comparable atmospheric waves are identified using atmospheric modeling with the MarsWRF general circulation model in a “nested” high spatial resolution mode. With the support of the modeling, we find these waves best fit the expected properties of inertia‐gravity waves with horizontal wavelengths of O(100s) of km. Measuring air pressure from the surface of Mars has revealed a wide variety of atmospheric phenomena. The Curiosity rover's record or surface air pressure is now the longest yet made on Mars. We use the first ∼8 years of Curiosity's pressure observations to look for atmospheric waves with periods of tens of minutes to hours. We find these waves have a clear pattern in their daily behavior with the strongest activity in the early morning and late evening and a seasonal cycle with the strongest waves in the second half of the Martian year (Northern hemisphere fall and winter). The strongest of such waves occurred in 2018 during a global dust storm. We find comparable waves in atmospheric modeling. With the support of modeling, we find these waves best fit the expected properties of buoyancy waves forced by airflow over topography with horizontal wavelengths of 100–1,000 km. We detect atmospheric pressure waves with periods of tens of minutes to 3 h with Mars Science Laboratory Rover Environmental Monitoring Station observationsWe find comparable waves in mesoscale atmospheric simulations with the MarsWRF general circulation modelBased on their characteristics, we interpret waves with periods greater than 1 h as topographically forced inertia‐gravity waves We detect atmospheric pressure waves with periods of tens of minutes to 3 h with Mars Science Laboratory Rover Environmental Monitoring Station observations We find comparable waves in mesoscale atmospheric simulations with the MarsWRF general circulation model Based on their characteristics, we interpret waves with periods greater than 1 h as topographically forced inertia‐gravity waves more...