Cirrus cloud tropopause prevents the warm, moist air forming the thunderstorm from rising any higher, thus creating the flat top. In the tropics, these thunderstorms occasionally produce copious amounts of cirrus from their anvils. High-altitude winds commonly push this dense mat out into an anvil shape that stretches downwind as much as several kilometers. Individual cirrus cloud formations can be the remnants of anvil clouds formed by thunderstorms. In the dissipating stage of a cumulonimbus cloud, when the normal column rising up to the anvil has evaporated or dissipated, the mat of cirrus in the anvil is all that is left. Contrails
UK Government G-Cloud COO of GDS, took over as director of G-Cloud. A new version of the G-Cloud framework is normally released about every 6 to 9 months. G-Cloud version 9 went live in May 2017; as of November 2017, the release date for version 10 had not been finalised. G-Cloud had several calls for contract to establish framework agreements. Major US vendors Amazon Web Services (AWS) and Google were initially excluded by the UK government in 2012 (G-Cloud 3) but AWS has since been added in 2013 (G-Cloud 4). Following hints by the head of the programme, GDS chief operating officer Tony