Arcus cloud Arcus cloud An arcus cloud is a low, horizontal cloud formation, usually appearing as an accessory cloud to a cumulonimbus. Roll clouds and shelf clouds are the two main types of arcus. Arcus clouds most frequently form along the leading edge or "gust fronts" of thunderstorm outflow; some of the most dramatic arcus formations mark the gust fronts of derecho-producing convective systems. Roll clouds also may arise in the absence of thunderstorms, forming along the shallow cold air currents of some sea breeze boundaries and cold fronts. A shelf cloud is a low, horizontal, wedge-shaped arcus cloud. A shelf cloud
What Is Life what he needs from his old band – that insinuating hook sense – and uses it to frame an utterly comfortable metaphysical discourse". Alan Clayson describes "What Is Life" as a seemingly "lovey-dovey pop song" that "craftily renewed the simplistic tonic-to-dominant riff cliché", while Simon Leng credits Harrison's "innate ability to write very fine pop-rock songs" and deems the result "as innovative an exercise in rock-soul as The Temptations' 'Cloud Nine'". Among Harrison biographers, only Ian Inglis is less than enthusiastic, acknowledging that Barham's orchestration and the other musicians give the track "undoubted excitement and energy", but lamenting that the