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This review describes the dynamic phenomena in the atmosphere of Mars that are visible in images taken in the visual range through cloud formation and dust lifting. We describe the properties of atmospheric features traced by aerosols covering a large range of spatial and temporal scales, including dynamical interpretations and modelling when available. We present the areographic distribution and the daily and seasonal cycles of those atmospheric phenomena. We rely primarily on images taken by cameras on Mars Express.

In a previous work (Hernandez-Bernal et al., 2021, ) we performed an observational analysis of the Arsia Mons Elongated Cloud (AMEC), which stands out due to its impressive size and shape, quick dynamics, and the fact that it happens during the Martian dusty season. Observations show that its morphology can be split in a head, on the western slope of the volcano of around 120 km in diameter; and a tail, that expands to the west reaching more than 1,000 km in length, making the AMEC the longest orographic cloud observed so far in the solar system. In this work we run the Laboratoire de Meteorologie Dynamique Mesoscale Model to gain insight into the physics of the AMEC. We note that it is coincident in terms of local time and seasonality with the fastest winds on the summit of Arsia Mons. A downslope windstorm on the western slope is followed by a hydraulic-like jump triggering a strong vertical updraft that propagates upwards in the atmosphere, causing a drop in temperatures of down to 30 K at 40-50 km in altitude, spatially and temporarily coincident with the observed head of the AMEC. However the model does not reproduce the microphysics of this cloud: the optical depth is too low and the expansion of the tail does not happen in the model. The observed diurnal cycle is correctly captured by the model for the head of the cloud. This work raises new questions that will guide future observations of the AMEC.

We report a previously unnoticed annually repeating phenomenon consisting of the daily formation of an extremely elongated cloud extending as far as 1,800 km westward from Arsia Mons. It takes place in the solar longitude (Ls) range of ∼220°–320°, around the Southern solstice. We study this Arsia Mons Elongated Cloud (AMEC) using images from different orbiters, including ESA Mars Express, NASA MAVEN, Viking 2, MRO, and ISRO Mars Orbiter Mission (MOM). We study the AMEC in detail in Martian year (MY) 34 in terms of local time and Ls and find that it exhibits a very rapid daily cycle: the cloud growth starts before sunrise on the western slope of the volcano, followed by a westward expansion that lasts 2.5 h with a velocity of around 170 m/s in the mesosphere (∼45 km over the areoid). The cloud formation then ceases, detaches from its formation point, and continues moving westward until it evaporates before the afternoon, when most sun-synchronous orbiters make observations. Moreover, we comparatively study observations from different years (i.e., MYs 29–34) in search of interannual variations and find that in MY33 the cloud exhibits lower activity, while in MY34 the beginning of its formation was delayed compared with other years, most likely due to the Global Dust Storm. This phenomenon takes place in a season known for the general lack of clouds on Mars. In this paper we focus on observations, and a theoretical interpretation will be the subject of a separate paper.

We present the first systematic study of clouds observed during twilight on Mars. We analyze images obtained by the Visual Monitoring Camera (VMC) on Mars Express between 2007 and 2020. Using an automated retrieval algorithm we found 407 cases of clouds observed at twilight, in which the geometry of the observations allows to derive the minimum altitude, revealing that many of these clouds are in the mesosphere (above 40km and up to 90km). The majority of these mesospheric clouds were detected in mid-latitudes at local autumn and winter, a new trend only hinted at by previous studies. In particular, we find a massive concentration of clouds in the southern mid-latitudes between Terra Cimmeria and Aonia, a region where high altitude events have been previously observed. We propose that there is an unknown mechanism in these regions that enhances the probability to host high altitude clouds around the southern winter solstice.

We study the 2018 Martian global dust storm (GDS 2018) over the Southern Polar Region using images obtained by the Visual Monitoring Camera (VMC) on board Mars Express (MEx) during June and July 2018. Dust penetrated into the polar cap region but never covered the cap completely, and its spatial distribution was nonhomogeneous and rapidly changing. However, we detected long but narrow aerosol curved arcs with a length of ~2,000–3,000 km traversing part of the cap and crossing the terminator into the nightside. Tracking discrete dust clouds allowed measurements of their motions that were toward the terminator with velocities up to 100 m/s. The images of the dust projected into the Martian limb show maximum altitudes of ~70 km but with large spatial and temporal variations. We discuss these results in the context of the predictions of a numerical model for dust storm scenario.

We analyze the onset and initial expansion of the 2018 Martian Global Dust Storm (GDS 2018) using ground-based images in the visual range. This is the first case of a confirmed GDS initiating in the Northern Hemisphere. A dusty area extending about 1.4×105 km2 and centered at latitude +31.7°±1.8° and west longitude 18°±5°W in Acidalia Planitia was captured on 30 and 31 May 2018 (Ls = 184.9°). From 1 to 8 June, daily image series showed the storm expanding southward along the Acidalia corridor with velocities of 5 m/s and simultaneously progressing eastward and westward with horizontal velocities ranging from 5 to 40 m/s. By 8 June the dust reached latitude -55° and later penetrated in the South polar region, whereas in the North the dust progression stopped at latitude approximately +46°. We compare the onset and expansion stage of this GDS with the previous confirmed storms.

This article is the result of analysis study done apprentices Trade Center and the Regional Tolima ser­vices with respect to his personal conception, their ideas, or their imaginary in relation to the concept of research in the formative stage. The development of this study is structured as the first link dis­sertation project line IFPI research. This analysis is of great importance for future triangulations of information with other points that converge in it, as they are; the training project and instructors, all of these are factors or aspects of first level involved at all times in the development of training, therefore they deserve a dedication and good analytical examination of its concepts and a review of its use in the formative act. The study of this fundamental point of the project was implemented in the first instance by the con­struction valuation expert judgment and later field application of a structured questionnaire used each learners training entitled the center of trade and services. Following this analysis and processing of information generated by participants, which was processed with SPSS software and its results and transcendence shows us a clear reality of what is on whether the investigation for the main actor pro­ceeded and construct “the newbie”., Este artículo es el resultado del análisis de estudio hecho a los aprendices del Centro de Comercio y Servicios de la Regional Tolima, con respecto a su concepción personal, sus ideas, o sus imaginarios en relación con el concepto de investigación en la etapa formativa. El desarrollo de este estudio está estructurado como el primer eslabón de disertación del proyecto de la línea de investigación IFPI. Este análisis tiene gran trascendencia para futuras triangulaciones de información con otros puntos que convergen en él, como lo son el proyecto formativo y los instructores. Todos estos son factores o aspectos de primer nivel que participan en todo momento en el desarrollo de la formación, por lo tanto merecen una dedicación y un buen examen analítico de sus conceptos y una revisión de su uso en el acto formativo.El estudio de este punto fundamental del proyecto, se ejecutó en primera instancia por medio de la construcción, valoración por juicio de expertos y posteriormente, aplicación en campo de una encuesta aplicada a cada uno de los aprendices de formación titulada del centro de comercio y servicios. Posterior a ello se procedió al análisis y tratamiento de la información generada por los participantes, la cual fue procesada con el software SPSS y sus resultados y trascendencia dan a conocer con claridad lo que es en sí la investigación para el actor principal y en constructo el aprendiz.

With the purpose of evaluating the operation of Public Health Surveillance System (PHSS) from the different actors of the General Security Health System (GSHS) in Medellin, a descriptive study with prospective collection of the information for the period between July 1998 and June 1999 was made. The sample was made with the 100% of EPS, ARS, EAS, DLS and DSS and then a systematic random sample of the IPS (notifier and non notifier). 79% of the interviewed establishments were of private character and 98.5% were in the urban area. From the total of the sample, only 38% have a committee in charge of Public Health Surveillance. Within the institutions that have a conformed committee in charge of the functions (38.0%), only a third perform opportunely with them. In 54.5% of institutions, the epidemiological information is not analyzed. The main difficulties for the accomplishment of the functions and responsibilities of Public Health Surveillance are: lack of knowledge respect to all actors of the system, lack of feedback of the information within the system, and lack of compromise of health Workers. According to the accomplishment of functions it was a meaning difference between institutions with conformed committee and only one person in charge. The institutions that does not have committee accomplish these functions with a low percentage, between 9% and 15%, nevertheless the institutions with committee has a percentage between 69 and 81 %. The opportunity in the accomplishment of functions has a major proportion for institutions with committee, 82.3% against 4.2% in the case of one person in charge. Generally, it was found that the actions developed inside the Public Health Surveillance System are essentially of assistance character and as a response for the solving of events that are presented and that affect the public health. These actions don't consider the affiliated neither the users, besides no intersectorial work is evidenced. It's recommended to put in functi, Con el propósito de evaluar el funcionamiento del Sistema de Vigilancia en Salud Pública (SVSP) desde los diferentes actores del Sistema General de Seguridad Social en Salud (SGSSS), del municipio de Medellín, se realizó un estudio descriptivo con toma prospectiva de la información para el período comprendido entre Julio del 98 y Junio del 99. Se tomó el 100% de las EPS, ARS, EAS, DLS, DSS y posteriormente por muestreo aleatorio sistemático se seleccionaron las IPS (notificadoras y no notificadoras). Las instituciones entrevistadas son en un 79.0% de carácter privado, y el 98.5% se encuentran ubicadas en el área urbana de la ciudad. Del total de la muestra sólo el 38.0% tiene conformado un comité de VSP, y de éstas sólo un 32.8.0% cumple oportunamente con las funciones, siendo las principales dificultades para el cumplimiento de las responsabilidades: la falta de conocimiento al respecto por parte de todos los actores, la falta de la retroalimentación de la información, y la falta de compromiso del personal de salud. Hay diferencia estadísticamente significativa entre las instituciones con un comité conformado y una sola persona asignada para el cumplimiento de funciones: las instituciones que no tienen comité cumplen en forma muy baja las funciones respectivas (9% a 15%), en cambio para las instituciones con comité esta proporción es importante (69% a 81 %). La oportunidad en el cumplimiento de las funciones presentó una mayor proporción para las instituciones con comité, 82.3% contra un 4.2% cuando sólo existe una persona encargada. En general se encontró que las acciones que se desarrollan dentro del SVSP son esencialmente de carácter asistencial y como respuesta a la solución de eventos que se presentan y afectan la salud pública. Estas acciones no involucran a la población usuaria, ni afiliada; además no se evidencia un trabajo intersectorial. Los autores recomiendan poner en funcionamiento los comités de vigilancia en salud pública, desarrollar acciones tendie