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Laboratoire Interuniversitaire des Systèmes Atmosphériques

LISA

Tutelles >

Université Paris Diderot - Paris 7

UFR de rattachement >

UFR Chimie

Label unité >

UMR 7583

Présentation

Le LISA, Laboratoire Interuniversitaire des Systèmes Atmosphériques est une unité de recherche de structure originale dépendant des Universités Paris Est Créteil et Paris Diderot, et du CNRS (UMR CNRS 7583).

Le LISA compte environ 130 personnes, dont 50 enseignants-chercheurs et chercheurs (CNRS & IRD), 36 ITA-IATOS et environ 45 post-doctorants, doctorants et étudiants de Master.

Il dispose d'un important potentiel technique et expérimental réparti sur 3.600m² de locaux à Créteil et d'une antenne opérationnelle sur le site Paris Rive Gauche, incluant aussi des équipements lourds. Les recherches y sont développées autour d’un thème générale : l’Atmosphère (comme le nom du laboratoire l’indique), Ses principaux thèmes de recherche portent ainsi sur la compréhension du fonctionnement des atmosphères terrestres et planétaires, et des impacts liés à la modification de la composition de l'atmosphère par les activités humaines. Les méthodes utilisées sont fondées sur des observations en atmosphère réelle, sur de la simulation expérimentale en laboratoire et de la modélisation numérique.

Pour mener à bien ces recherches, le LISA regroupe des scientifiques de plusieurs disciplines : physiciens, géochimistes, environnementalistes et une majorité de chimistes. Ce dernier aspect est une de ses caractéristiques importantes par rapport aux autres laboratoires du domaine. Un département technique (doté de 4 pôles : chimie, instrumentation, terrain et informatique) et un département administratif sont en soutien des activités de recherche.

Thèmes de recherche

Pollution atmosphérique Oxydante et Particulaire
Devenir du Carbone Organique
Cycle de l’Aérosol Désertique
Spectroscopie et Atmosphères
Exobiologie et Astrochimie

[hal-00480380] Variation of atmospheric volatile organic compounds over the Southern Indian Ocean (30–49°S)

Date: 4 Mayo 2010 - 11:04

Desc: [...]

[hal-02105649] The 7–13 March 2006 major Saharan outbreak: Multiproxy characterization of mineral dust deposited on the West African margin

Date: 21 Abr 2019 - 17:08

Desc: Mineral dust deposits were collected at Mbour, Senegal, throughout the spring of 2006 and especially during the well‐documented March 7–13 large Saharan dust outbreak. During this 7‐day period, significant changes in mass flux, grain‐size, clay mineralogy and Sr and Nd isotopic compositions were recorded, indicating distinct provenances for the dust transported and deposited during and outside the event. All these terrigenous proxies, as well as freshwater diatom taxa, also showed significant temporal variations during the outbreak, implying contributions from at least two different provenance regions. Tri‐dimensional back‐trajectories and satellite imaging enabled us to link those distinct signatures to regions increasingly to the southeast within a large area covering Mauritania, Mali and southern Algeria, identified by the Total Ozone Mapping Spectrometer (TOMS) as the main source of the prominent winter/spring plume over the tropical Atlantic. The multiproxy characterization of the March 7–13 dust fall therefore enables us to typify the terrigenous signature of two different regions supplying dust off West Africa, and provide valuable clues for the interpretation of Northeastern Tropical Atlantic Ocean dust sedimentary records in terms of changes in provenance regions and transport systems. Additionally, because dust deposition data are scarce, flux and grain size data obtained in this study, among other parameters such as clay assemblages, provide important constraints for atmospheric transport models and dust deposition budget estimates in this area.

[hal-02347537] New constraints on elemental and Pb and Nd isotope compositions of South American and Southern African aerosol sources to the South Atlantic Ocean

Date: 28 Ago 2020 - 19:19

Desc: Improving the geochemical database available for characterising potential natural and anthropogenic aerosol sources from South America and Southern Africa is a critical precondition for studies aimed at understanding trace metal controls on the marine biogeochemical cycles of the South Atlantic Ocean. We here present new elemental and isotopic data for a wide range of sample types from South America and Southern Africa that are potentially important aerosol sources. This includes road dust from Buenos Aires and lichen samples from Johannesburg, soil dust from Patagonia, volcanic ash from the Andean volcanic belt, and aerosol samples from São Paulo. All samples were investigated for major (Al, Ca, Fe, Mg, Na, K, Mn) and trace element (Cd, Co, Cr, Cu, Ni, Pb, REE, Sc, Th, Y, V, Zn) concentrations and Nd and Pb isotopic compositions. We show that diagrams of 208Pb/207Pb vs. εNd, 208Pb/207Pb vs. Pb/Al, 1/[Pb], Zn/Al, Cd/Al, Cu/Al, and εNd vs. Pb/Al, and 1/[Nd] are best suited to separate South American and South African source regions as well as natural and anthropogenic sources. A subset of samples from Patagonia and the Andes was additionally subjected to separation of a fine (<5 μm) fraction and compared to the composition of the bulk sample. We show that differences in the geochemical signature of bulk samples between individual regions and source types are significantly larger than between grain sizes. Jointly, these findings present an important step forward towards a quantitative assessment of aeolian trace metal inputs to the South Atlantic Ocean.

[hal-04753994] Analysis of New Measurements of 18O-substituted Isotopic Species 16O16O18O and 16O18O16O of Ozone in the THz and Far-Infrared Ranges

Date: 28 Oct 2024 - 08:11

Desc: Abstract High-resolution spectra corresponding to the rotational and the ν 2 –ν 2 bands of the two most abundant isotopic species of ozone with one heavy 18 O oxygen atom were recorded using SOLEIL synchrotron radiation source in the range 30–200 cm −1 . Additionally, the ν 2 vibrational-rotational bands were recorded between 550 and 880 cm −1 using a classical glowbar source that made it possible to extend and refine information compared to published data on the observed transitions of these bands. The analyses of recorded spectra permitted us to deduce experimental set of energy levels for the ground (000) and the first bending (010) vibrational states, which significantly exceeds literature data in terms of rotational quantum numbers. For both isotopic species, the weighted fits of all experimental line positions were carried out including previously published microwave data. As a result of this work, the improved values of rotational and centrifugal distortion parameters for the states (000) and (010) were obtained that permitted modelling the experimental line positions with a weighted standard deviation of 1.284 (2235 transitions) and 0.908 (4597 transitions), respectively, for 16 O 16 O 18 O, and 1.168 (824 transitions) and 1.724 (2381 transitions) for 16 O 18 O 16 O.

[hal-01262324] Experimental Determination of the Directional Emissivity of Materials Using a Periodic Thermal Excitation Coupled with Infrared Thermography

Date: 26 Ene 2016 - 15:44

Desc: Variation of directional emissivity upon emission angle can be deduced theoretically from the complex refraction index. Nevertheless, theoretical relations are only valid for perfectly smooth surfaces and homogeneous materials. Directional emissivity is generally nearly constant for emission angles lower than 60 degrees from the normal incidence, but strong variations are expected for angles higher than 60 degrees either for dielectric materials or for conducting ones. Many experimental devices were developed to determine directional emissivity of materials. Generally, these devices are quite complex and fail in measuring directional emissivity for angles greater than 80 degrees. Thus, it is still difficult to point out deviations between theoretical and experimental values for high emission angles. Current work concerns the development of a device (SPIDER Instrument) allowing to determine directional emissivity of dielectric or conducting materials. The rear face of the sample is heated periodically. Temperature variations are recorded using a thermocouple. Sample surface temperature variations are recorded using an infrared camera. By comparing at several frequencies and emission angles, the temperature amplitudes recorded, it is possible to determine relative variations of directional emissivity. If directional emissivity is known at a given emission angle, then directional emissivity can be calculated at any emission angle