Civil Aircraft for the regular investigation of the atmosphere based on an instrumented container: The new CARIBIC system

An airfreight container with automated instruments for measurement of atmospheric gases and trace compounds was operated on a monthly basis onboard a Boeing 767-300 ER of LTU International Airways during long-distance flights from 1997 to 2002 (CARIBIC, Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container, http://www.caribic-atmospheric.com). Subsequently a more advanced system has been developed, using a larger capacity container with additional equipment and an improved inlet system. CARIBIC phase #2 was implemented on a new long-range aircraft type Airbus A340-600 of the Lufthansa German Airlines (Star Alliance) in December 2004, creating a powerful flying observatory. The instrument package comprises detectors for the measurement of O3, total and gaseous H2O, NO and NOy, CO, CO2, O2, Hg, and number concentrations of sub-micrometer particles (>4 nm, >12 nm, and >18 nm diameter). Furthermore, an optical particle counter (OPC) and a proton transfer mass spectrometer (PTR-MS) are incorporated. Aerosol samples are collected for analysis of elemental composition and particle morphology after flight. Air samples are taken in glass containers for laboratory analyses of hydrocarbons, halocarbons and greenhouse gases (including isotopic composition of CO2) in several laboratories. Absorption tubes collect oxygenated volatile organic compounds. Three differential optical absorption spectrometers (DOAS) with their telescopes mounted in the inlet system measure atmospheric trace gases such as BrO, HONO, and NO2. A video camera mounted in the inlet provides information about clouds along the flight track. The flying observatory, its equipment and examples of measurement results are reported

High-resolution laser system for the S3-Low Energy Branch

In this paper we present the first high-resolution laser spectroscopy results obtained at the GISELE laser laboratory of the GANIL-SPIRAL2 facility, in preparation for the first experiments with the S$^3$-Low Energy Branch. Studies of neutron-deficient radioactive isotopes of erbium and tin represent the first physics cases to be studied at S$^3$. The measured isotope-shift and hyperfine structure data are presented for stable isotopes of these elements. The erbium isotopes were studied using the $4f^{12}6s^2$ $^3H_6 \rightarrow 4f^{12}(^3 H)6s6p$ $J = 5$ atomic transition (415 nm) and the tin isotopes were studied by the $5s^25p^2 (^3P_0) \rightarrow 5s^25p6s (^3P_1)$ atomic transition (286.4 nm), and are used as a benchmark of the laser setup. Additionally, the tin isotopes were studied by the $5s^25p6s (^3P_1) \rightarrow 5s^25p6p (^3P_2)$ atomic transition (811.6 nm), for which new isotope-shift data was obtained and the corresponding field-shift $F_{812}$ and mass-shift $M_{812}$ factors are presented

Atmospheric CO 2 modeling at the regional scale: Application to the CarboEurope Regional Experiment

International audience[1] The CarboEurope Regional Experiment Strategy (CERES) experiment took place in May and June 2005 in France and offers a comprehensive database on atmospheric CO 2 and boundary layer processes at the regional scale. One ''golden'' day of CERES is interpreted with the mesoscale atmospheric model Meso-NH coupled on-line with the Interactions between Soil, Biosphere and Atmosphere, CO 2-reactive (ISBA-A-gs) surface scheme, allowing a full interaction of CO 2 between the surface and the atmosphere. The rapid diurnal cycle of carbon coupled with water and energy fluxes is parameterized including, e.g., plant assimilation, respiration, anthropogenic emissions, and sea fluxes. During the analyzed day, frequent vertical profiles and aircraft transects revealed high spatial and temporal variabilities of CO 2 concentrations within the boundary layer at the regional scale: a 10-ppm gradient of CO 2-mixing ratio is observed during the day by the aircraft measurements. The Meso-NH model proved able to simulate very well the CO 2 concentration variability as well as the spatial and temporal evolution of the surface fluxes and the boundary layer in the domain. The model is used to explain the CO 2 variability as a result of two complementary processes: (1) the regional heterogeneity of CO 2 surface fluxes related to the land cover (e.g., winter crops versus a pine forest) and (2) the variability of mesoscale circulation across the boundary layer: development of the sea breeze in the western part of the domain and dominating wind flow in the eastern part of the domain

The YAK-AEROSIB transcontinental aircraft campaigns: new insights on the transport of CO 2 , CO and O 3 across Siberia

International audienceTwo airborne campaigns were carried out to measure the tropospheric concentrations and variability of CO 2 , CO and O 3 over Siberia. In order to quantify the influence of remote and regional natural and anthropogenic sources, we analysed a total of 52 vertical profiles of these species collected in April and September 2006, every ∼200 km and up to 7 km altitude. CO 2 and CO concentrations were high in April 2006 (respectively 385-390 ppm CO 2 and 160-200 ppb CO) compared to background values. CO concentrations up to 220 ppb were recorded above 3.5 km over eastern Siberia, with enhancements in 500-1000 m thick layers. The presence of CO enriched air masses resulted from a quick frontal uplift of a polluted air mass exposed to northern China anthropogenic emissions and to fire emissions in northern Mongolia. A dominant Asian origin for CO above 4 km (71.0%) contrasted with a dominant European origin below this altitude (70.9%) was deduced both from a transport model analysis, and from the contrasted CO/ CO 2 ratio vertical distribution. In September 2006, a significant O 3 depletion (∼-30 ppb) was repeatedly observed in the boundary layer, as diagnosed from virtual potential temperature profiles and CO 2 gradients, compared to the free troposphere aloft, suggestive of a strong O 3 deposition over Siberian forests