396 research outputs found
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Towards a global model of the martian atmosphere
In an effort to continuously improve the capabilities of the Martian atmospheric predictions at LMD, the GCM has been extended into thermospheric heights thus creating the first model to self-consistently couple the lower and upper
regions of the Martian atmosphere. The behaviour of
the Martian thermosphere is strongly influenced by
lower atmospheric processes and has complex dynamics.
Such a fully coupled model will certainly aid in the preparation of future missions and on the analysis of future high altitude data, as well as serve as a base for the simulation of ionospheric processes, escape, etc
Variability of the Martian thermosphere during eight Martian years as simulated by a ground-to-exosphere global circulation model
Using a ground-to-exosphere general circulation model for Mars we have simulated the variability of the dayside temperatures at the exobase during eight Martian years (MY, from MY24 to MY31, approximately from 1998 to 2013), taking into account the observed day-to-day solar and dust load variability. We show that the simulated temperatures are in good agreement with the exospheric temperatures derived from Precise Orbit Determination of Mars Global Surveyor. We then study the effects of the solar variability and of two planetary-encircling dust storms on the simulated temperatures. The seasonal effect produced by the large eccentricity of the Martian orbit translates in an aphelion-to-perihelion temperature contrast in every simulated year. However, the magnitude of this seasonal temperature variation is strongly affected by the solar conditions, ranging from 50 K for years corresponding to solar minimum conditions to almost 140 K during the last solar maximum. The 27 day solar rotation cycle is observed on the simulated temperatures at the exobase, with average amplitude of the temperature oscillation of 2.6 K but with a significant interannual variability. These two results highlight the importance of taking into account the solar variability when simulating the Martian upper atmosphere and likely have important implications concerning the atmospheric escape rate. We also show that the global dust storms in MY25 and MY28 have a significant effect on the simulated temperatures. In general, they increase the exospheric temperatures over the low latitude and midlatitude regions and decrease them in the polar regions.©2015. American Geophysical Union. All Rights Reserved.F.G.G. was partly funded by a CSIC JAE-Doc grant financed by the European Social Fund. F.G.G., M.-A.L.V., and M.G.C. thank the Spanish MICINN for funding support through the CONSOLIDER program ASTROMOLCSD2009-00038 and through projects AYA2011-23552/ESP and AYA2012-39691-C02-01. This work has also been partially funded by the ESA-CNES project Mars Climate Database and Physical Models.Peer Reviewe
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The latest (version 4.3) Mars Climate Database
Introduction: The Mars Climate Database (MCD) is a database of meteorological fields derived from General Circulation Model (GCM) numerical simulations of the Martian atmosphere and validated using available observational data. The MCD includes complementary post-processing schemes such as high spatial resolution interpolation of environmental data and means of reconstructing the variability thereof. The GCM is developed at Laboratoire de Météorologie Dynamique du CNRS (Paris, France) [1,2] in collaboration with the Open University (UK), the Oxford University (UK) and the Instituto de Astrofisica de Andalucia (Spain) with support from the European Space Agency (ESA) and the Centre National
d'Etudes Spatiales (CNES)
Community pharmacy is the key to improving vitamin D levels
Introduction: Vitamin D is an essential micronutrient that participates in the body's fundamental physiological processes.
The pharmacist should involve the patient in his medication adherence, leading to a change in the patient's attitude
towards his medication and towards his health problem, in order to achieve the pharmacological objective set.
Methods: Quasi-experimental multicenter study design with non-probabilistic convenience sampling. A pharmacist-led
intervention in health educationwas carried out, divided in two groups, face-to-face interviewand on-line survey, and
the results were evaluated 3 months later to observe if there was any change in the patient's health status or in their
vitamin D levels.
Results: The study was conducted in four pharmacies through face-to-face interviews (n=49 patients) and online surveys
(n = 23). Pharmaceutical intervention improved habits of exercise (0.81 ± 1.44 days/week face-to-face interviews
vs −0.09 ± 2.35 days/week online surveys (p = 0.048)). In face-to-face interviews, consumption of vitamin
D-rich foods was increased (0.55 unit of tuna/week; p = 0.035 and 0.56 unit of avocado/week; p = 0.001) and
was improved correct intake of vitamin D supplements (32.5% baseline to 69.8% at 3 months). The increase in 25-
hydroxyvitamin D levels (11.5 ng/mL after 3 months (p = 0.021)) was correlated to salmon consumption (0.951;
p = 0.013) and the improvement of quality of life was correlated to avocado consumption (1; p < 0.001).
Conclusion: There are habits that improve vitamin D production such as increased physical activity, the correct use of
vitamin D supplements and the consumption of foods with high vitamin D levels. The role of the pharmacist is crucial,
involving the patient in the treatment making aware of the benefits for his/her health status of increasing vitamin D
levels
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Back to the basics: improving the prediction of temperature, pressure and winds in the LMD general circulation model
International audienc
IAA : Información y actualidad astronómica (34)
Sumario : Ondas gravitatorias: la otra luz del cosmos.--
El camino hacia el interior de las estrellas.--
DECONSTRUCCIÓN Y otros ENSAYOS. Clima marciano.--
EL “MOBY DICK” DE... Javier Gorosabel (IAA-CSIC).--
CIENCIA EN HISTORIAS. Antonia Maury: un espíritu libre.--
ACTUALIDAD.--
ENTRE BASTIDORES.--
CIENCIA: PILARES E INCERTIDUMBRES. Atmósfera de Marte.--
RECOMENDADOS.N
Study of the hydrogen escape rate at Mars during Martian years 28 and 29 from comparisons between SPICAM/Mars Express observations and GCM-LMD simulations
EPSC-DPS Joint Meeting 2019, held 15-20 September 2019 in Geneva, Switzerland, id. EPSC-DPS2019-499-2.-
© Author(s) 2019. CC Attribution 4.0 license. https://creativecommons.org/licenses/by/4.0/deed.esWe simulate the 3D Martian hydrogen corona during the Martian years 28 and 29 at different solar longitudes using a set of models of atomic hydrogen density from the surface to the exosphere. These simulations are compared to Mars Express / SPICAM observations and show a strong underestimate of the brightness by our models near southern summer that could be due to an underestimate of the amount of water vapor delivered to the upper atmosphere at this season
Updating known distribution models for forecasting climate change impact on endangered species
To plan endangered species conservation and to design adequate management programmes, it is necessary to predict their
distributional response to climate change, especially under the current situation of rapid change. However, these
predictions are customarily done by relating de novo the distribution of the species with climatic conditions with no regard
of previously available knowledge about the factors affecting the species distribution. We propose to take advantage of
known species distribution models, but proceeding to update them with the variables yielded by climatic models before
projecting them to the future. To exemplify our proposal, the availability of suitable habitat across Spain for the endangered
Bonelli’s Eagle (Aquila fasciata) was modelled by updating a pre-existing model based on current climate and topography to
a combination of different general circulation models and Special Report on Emissions Scenarios. Our results suggested that
the main threat for this endangered species would not be climate change, since all forecasting models show that its
distribution will be maintained and increased in mainland Spain for all the XXI century. We remark on the importance of
linking conservation biology with distribution modelling by updating existing models, frequently available for endangered
species, considering all the known factors conditioning the species’ distribution, instead of building new models that are
based on climate change variables only.Ministerio de Ciencia e Innovación and FEDER (project CGL2009-11316/BOS
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