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Data Availability Statement All Mars 2020 MEDA data necessary to reproduce each figure shown in this manuscript are available via the Planetary Data System (PDS) Atmospheres node (Rodriguez-Manfredi & de la Torre Juarez, 2021). An exception to this are the LWd values in the 5–80 μm range (Figures 8, 9, and 10 top, Figure 11 top, and Figure 15), and the aerosol opacity values derived from TIRS (Figure 10, middle and Figure 11, top), which are publicly available via the USRA Houston Repository (Martinez et al., 2022). THEMIS retrievals of thermal inertia shown in Figure 7 and TES retrievals of albedo in Figure 14 can be queried and processed using the open-source JMARS (Christensen et al., 2009) and MARSTHERM (Putzig et al., 2013) software. The Mars Environmental Dynamics Analyzer (MEDA) on board Perseverance includes first-of-its-kind sensors measuring the incident and reflected solar flux, the downwelling atmospheric IR flux, and the upwelling IR flux emitted by the surface. We use these measurements for the first 350 sols of the Mars 2020 mission (Ls ∼ 6°–174° in Martian Year 36) to determine the surface radiative budget on Mars and to calculate the broadband albedo (0.3–3 μm) as a function of the illumination and viewing geometry. Together with MEDA measurements of ground temperature, we calculate the thermal inertia for homogeneous terrains without the need for numerical thermal models. We found that (a) the observed downwelling atmospheric IR flux is significantly lower than the model predictions. This is likely caused by the strong diurnal variation in aerosol opacity measured by MEDA, which is not accounted for by numerical models. (b) The albedo presents a marked non-Lambertian behavior, with lowest values near noon and highest values corresponding to low phase angles (i.e., Sun behind the observer). (c) Thermal inertia values ranged between 180 (sand dune) and 605 (bedrock-dominated material) SI units. (d) Averages of albedo and thermal inertia (spatial resolution of ∼3–4 m2) along Perseverance's traverse are in very good agreement with collocated retrievals of thermal inertia from Thermal Emission Imaging System (spatial resolution of 100 m per pixel) and of bolometric albedo in the 0.25–2.9 μm range from (spatial resolution of ∼300 km2). The results presented here are important to validate model predictions and provide ground-truth to orbital measurements. Germán Martínez wants to acknowledge JPL funding from USRA Contract Number 1638782. A. V. R. is supported by the Spanish State Research Agency (AEI) Project MDM-2017-0737, Unidad de Excelencia “María de Maeztu”—Centro de Astrobiología (INTA-CSIC), and by the Comunidad de Madrid Project S2018/NMT-4291 (TEC2SPACE-CM). J. J. acknowledges funding from Mastcam-Z ASU subcontract 15-707. R. H., A. S. L., and A. M. were supported by Grant PID2019-109467GB-I00 funded by MCIN/AEI/10.13039/501100011033/ and by Grupos Gobierno Vasco IT1742-22. F. G. acknowledges financial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación and the European Regional Development Fund “A way of making Europe” through project the Centre of Excellence “María de Maeztu” award to the Centro de Astrobiología (MDM-2017-0737), and from the Instituto Nacional de Técnica Aeroespacial through Project S.IGS22001. L. M. was supported by CNES and IRIS-OCAV. J. P., M. H., and A.-M. H. are thankful for the Finnish Academy Grant 310509. M.-P. Z. was supported by Grant PID2019-104205GB-C21 funded by MCIN/AEI/10.13039/501100011033. M. de la T. J. acknowledges partial funding from the National Aeronautics and Space Administration (80NM0018D0004). The JPL co-authors acknowledge funding from NASA's Space Technology Mission Directorate and the Science Mission Directorate. Peerreview

We characterize vortex and dust devils (DDs) at Jezero from pressure and winds obtained with the Mars Environmental Dynamics Analyzer (MEDA) instrument on Mars 2020 over 415 Martian days (sols) (Ls = 6°–213°). Vortices are abundant (4.9 per sol with pressure drops >0.5 Pa correcting from gaps in coverage) and they peak at noon. At least one in every five vortices carries dust, and 75% of all vortices with Δp > 2.0 Pa are dusty. Seasonal variability was small but DDs were abundant during a dust storm (Ls = 152°–156°). Vortices are more frequent and intense over terrains with lower thermal inertia favoring high daytime surface-to-air temperature gradients. We fit measurements of winds and pressure during DD encounters to models of vortices. We obtain vortex diameters that range from 5 to 135 m with a mean of 20 m, and from the frequency of close encounters we estimate a DD activity of 2.0–3.0 DDs km−2 sol−1. A comparison of MEDA observations with a Large Eddy Simulation of Jezero at Ls = 45° produces a similar result. Three 100-m size DDs passed within 30 m of the rover from what we estimate that the activity of DDs with diameters >100 m is 0.1 DDs km−2sol−1, implying that dust lifting is dominated by the largest vortices in Jezero. At least one vortex had a central pressure drop of 9.0 Pa and internal winds of 25 ms−1. The MEDA wind sensors were partially damaged during two DD encounters whose characteristics we elaborate in detail. The authors are very grateful to the entire Mars 2020 science operations team. The authors would also like to thank Lori Fenton and an anonymous reviewer for many suggestions that greatly improved the manuscript. This work was supported by Grant PID2019-109467GB-I00 funded by MCIN/AEI/10.13039/501100011033/ and by Grupos Gobierno Vasco IT1742-22 and by the Spanish National Research, Development and Innovation Program, through the Grants RTI2018-099825-B-C31, ESP2016-80320-C2-1-R, and ESP2014-54256-C4-3-R. Baptiste Chide is supported by the Director's Postdoctoral Fellowship from the Los Alamos National Laboratory. M. Lemmon is supported by contract 15-712 from Arizona State University and 1607215 from Caltech-JPL. R. Lorenz was supported by JPL contract 1655893. Germán Martínez acknowledges JPL funding from USRA Contract Number 1638782. A. Munguira was supported by Grant PRE2020-092562 funded by MCIN/AEI and by “ESF Investing in your future.” A. Vicente-Retortillo is supported by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia “María de Maeztu”-Centro de Astrobiología (INTA-CSIC), and by the Comunidad de Madrid Project S2018/NMT-4291 (TEC2SPACE-CM). Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). Finnish researchers acknowledge the Academy of Finland Grant 328 310529. Researchers based in France acknowledge support from the CNES for their work on Perseverance.