During the 2020 Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC) and ElUcidating the Role of Cloud- Circulation Coupling in ClimAte (EUREC4A) field campaigns, a team from the University of Colorado Boulder deployed the RAAVEN Remotely-Piloted Aircraft System (RPAS). The RAAVEN RPAS was equipped with the miniFlux measurement system to observe the marine boundary layer upwind of Morgan Lewis, Barbados. Over the course of 23 days, the team completed 39 flights covering nearly 80 flight hours. Flights were conducted in and just above the boundary layer at altitudes between 10 and 1000 m, with a focus on capturing regular thermodynamic and kinematic profiles of the lower atmosphere, along with statistics on vertical transport and spatial variability. In this presentation, we will give initial details on the observed state of the lower atmosphere. This includes information on the structure and internal variability of thermodynamic and kinematic properties, turbulence intensity, turbulent surface fluxes and their variability, and details on the structure of vertical velocities in the lower atmosphere.
La grotte de Bruniquel renferme six structures architecturees dont une grande et une plus petite plus ou moins circulaires et quatre accumulations, composees au total de 420 stalagmites entieres ou fragmentees, localisees a environ 300 metres de l’entree. Leur construction a ete datee en 2016 de 176 500 ± 2 100 ans (SIM 6) grâce a la datation uranium-thorium des stalagmites. Les Hommes de Neandertal ne seraient apparemment pas entres par l’acces actuel, l’eboulis d’entree etant scelle par plusieurs generations de stalagmites dont certaines tres massives. Il reste donc une inconnue quant a l’âge de cet eboulis et l’existence d’un eventuel porche d’entree contemporain de Neandertal. Dans cet article, la grotte est replacee dans son contexte geologique, karstologique et geomorphologique. Les nouvelles dates sur les structures affinent la limite minimale de l’âge des constructions et les premieres dates sur l’eboulis montrent quant a elles un âge relativement ancien sans toutefois pouvoir exclure une ouverture d’une partie de l’eboulis a ~170 ka.
Summary Many parts of the UK’s rail network were constructed in the mid-19th century long before the advent of modern construction standards. Historic levels of low investment, poor maintenance strategies and the deleterious effects of climate change have resulted in critical elements of the rail network being at significant risk of failure. The majority of failures which have occurred over recent years have been triggered by extreme weather events. Advance assessment and remediation of earthworks is, however, significantly less costly than dealing with failures reactively. It is therefore crucial that appropriate approaches for assessment of the stability of earthworks are developed, so that repair work can be better targeted and failures avoided wherever possible. This extended abstract briefly discusses some preliminary results from an ongoing geophysical research project being carried out in order to study the impact of climate or seasonal weather variations on the stability of a century old railway embankment on the Gloucestershire Warwickshire steam railway line in Southern England.
