TY - JOUR
T1 - Convective vortices and dust devils at the MSL landing site
T2 - Annual variability
AU - Kahanpää, H.
AU - Newman, C.
AU - Moores, J.
AU - Zorzano, M. P.
AU - Martín-Torres, J.
AU - Navarro, S.
AU - Lepinette, A.
AU - Cantor, B.
AU - Lemmon, M. T.
AU - Valentín-Serrano, P.
AU - Ullán, A.
AU - Schmidt, W.
N1 - Funding Information:
We wish to thank the REMS and MSL operations teams, especially Jose Antonio Rodr?guez-Manfredi and Veronica Peinado: without their hard work we would have no data to explore. Thanks also to the MSL ENV theme group for keeping the noontime ?dust devil search? block in the REMS cadence all the year round: without it we might have missed the sol 664 event. We are grateful to the International Space Science Institute (ISSI) for inviting several of the authors to the Dust Devil Workshop in February 2015 in Bern: several of the ideas presented here were inspired by that workshop. And thanks to Robert Haberle (NASA/Ames Research Center, USA) for bringing forth the idea that the lack of large pressure drops was related to the suppressed boundary layer. Annastiina Hukkanen (University of Eastern Finland) helped us by proofreading this article, thanks to her too. Last but not least, we wish to thank the reviewers Ralph Lorenz (The Johns Hopkins University, USA) and Aymeric Spiga (Laboratoire de M?t?orologie Dynamique, France): their valuable and constructive comments greatly improved this article. All authors are members or collaborators of the Mars Science Laboratory science team. The contribution of H. Kahanp?? was funded by the Finnish Meteorological Institute, by Jib Systems, Inc., and by the Finnish Education Fund. The MarsWRF simulations defined by C. Newman were performed on the Pleiades cluster at NASA's Ames Research Center, and this work was supported by NASA Mars Fundamental Research Program grant NNX11AF59G and Mars Science Laboratory grant 1449994. The contribution of J. Moores was supported by the Mars Science Laboratory Participating Scientist Program, funded through the Canadian Space Agency. The research of J. Mart?n-Torres was partly funded by Rymdstyrelsen (Swedish National Space Board) Research Program 2015-R, Dnr 154/15. The input of B. Cantor was funded by Malin Space Science System, Inc. and by NASA through the funding of the Mars Reconnaissance Orbiter mission. The funding of M.T. Lemmon was provided by NASA's Mars Exploration Program via the MastCam, MAHLI, and MARDI instrument contracts. The authors would also like to acknowledge the financial support to the REMS instrument team provided by the Spanish Ministry of Economy and Competitiveness (AYA2011-25720 and AYA2012-38707). The REMS data used in this study were obtained freely from the MSL REMS Reduced Data Record, Release number 9, released online on 31 July 2015 on the NASA Planetary Data System (http://atmos.nmsu.edu/data_and_services/atmospheres_data/MARS/curiosity/rems.html). The pressure, air temperature, ground temperature, and wind data are taken from the Models Reduced Data Record (MDR) [G?mez-Elvira,], and the ultraviolet intensity data are taken from the Environmental Magnitudes Reduced Data Record (ENV) [G?mez-Elvira,]. The simulated data have been generated by the MarsWRF numerical climate model, an adaptation of the Planetary Weather Research and Forecasting (planetWRF) model. The source code of planetWRF is freely available at http://planetwrf.com/download-planetwrf-v331.html, and the simulated data used in this study can be requested from Claire Newman, Aeolis Research Inc., 600 N Rosemead Blvd, Suite 205, Pasadena, CA 91107, USA, claire@aeolisresearch.com. The raw MARCI images used to generate the mosaics shown in Figure are available freely in the MARCI Experiment Data Record (EDR) Archive on the NASA Planetary Data System (https://pds.nasa.gov/ds-view/pds/viewDataset.jsp?dsid=MRO-M-MARCI-2-EDR-L0-V1.0) [Malin,].
Publisher Copyright:
©2016. American Geophysical Union. All Rights Reserved.
PY - 2016/8/1
Y1 - 2016/8/1
N2 - 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.
AB - 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.
KW - Mars
KW - convective vortices
KW - dust devils
KW - numerical modeling
KW - planetary atmospheres
UR - http://www.scopus.com/inward/record.url?scp=84983609815&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84983609815&partnerID=8YFLogxK
U2 - 10.1002/2016JE005027
DO - 10.1002/2016JE005027
M3 - Article
AN - SCOPUS:84983609815
SN - 2169-9097
VL - 121
SP - 1514
EP - 1549
JO - Journal of Geophysical Research: Planets
JF - Journal of Geophysical Research: Planets
IS - 8
ER -
