Definition of brown cloud in US English:

brown cloud


  • A visible pall of air pollutants that persists over a city or other area.

    ‘the Asian brown cloud’
    ‘throughout the day, air shifts in the valley cause variances in the brown cloud’
    • ‘After Olos had gone, she sank into a deep, much-needed sleep, un-plagued by dreams of oily brown clouds and droning.’
    • ‘When Klaus Toepfer broke the news that an elite group of scientists had found a dirty brown cloud hanging over India and much of Asia, he was caught unprepared by its immediate effects.’
    • ‘One look at the big brown cloud hanging perennially over Toronto and you know Rick Mercer is right: the first instinct is to run.’
    • ‘You fly into Africas richest city through a thick brown cloud.’
    • ‘NASA scientists announced a giant, smoggy atmospheric brown cloud, which forms over South Asia and the Indian Ocean, has intercontinental reach.’
    • ‘When I was young there was a brown cloud over the whole of the town.’
    • ‘The southern pollutant buildup has long-range effects, often traveling across Africa, far beyond the main brown cloud of particles.’
    • ‘It's a thick brown cloud that's covering parts of Asia.’
    • ‘In Fontana, 80 miles to the east of LA, on the way to Vegas, a giant brown cloud will end its creeping spread and give way to clear empty clean skies.’
    • ‘Besides producing ozone smog, they help form the dirty brown clouds that often hang over major cities, they contribute to acid rain and they play a role in global climate change.’
    • ‘The brown cloud which hangs over Asia was caused by pollution and will affect the monsoon rains in Asia.’
    • ‘However, the offensive brown cloud that hung over the city was not able to choke out the light of the moon.’
    • ‘But I stared, amazed by how thick the city's smog was, a brown cloud with only a few building spires murkily visible within it.’
    • ‘Atmospheric brown clouds, originating in Asia or elsewhere, are a concern not only because bad air quality affects health through increased mortality and breathing problems, but because they also have an impact on climate change.’
    • ‘The Asian cloud is only the first and largest of a number of high-atmosphere brown clouds scientists have discovered.’
    • ‘Even the brown cloud of smog that sometimes shadows Los Angeles is less of a factor now.’
    • ‘On many days wood fires are banned, as they add to the big brown cloud held in by atmospheric inversions.’
    • ‘Over everything hangs a brown cloud of pollution that is clearly visible from the hills outside the city.’
    • ‘Today, that is all gone: no brown cloud, no atmospheric pollution to speak of.’