English: Urban artificial cloudiness induced by urban warming (bubble heat) and particular pollution for Paris and London 2019, from a recent study : Natalie E. Theeuwes, Janet F. Barlow, Adriaan J. Teuling, C. Sue B. Grimmond & Simone Kotthaus (2019) Persistent cloud cover over mega-cities linked to surface heat release ; npj Climate and Atmospheric Science 2, Article number: 15 |Publié le 24 Mai 2019 published in open licence CC-BY-SA 4.0
Summer cloud cover over Paris and London regions. a, d The mean (circles) and median (squares) with the interquartile ranges (IQR, error bars) of the differences in cloud fraction between all urban pixels and all low-plant pixels (light green) and all forest pixels (dark green) for a Paris and d London. Only HRV pixels with 100% of one land cover type are analysed.
b), e) Afternoon (15:00–17:30 UTC) mean cloud fractions for b) Paris and e) London.
c), f) The CORINE land cover (250 m resolution)53 for c) Paris and f) London.
Data for days with a predominantly cumulus cloud class (see Methods) for 2009–2018 in May, June, July and August. (e), f) dots) Locations of London and Chilbolton sites, (b), c), e), f triangles) airport sites used to select cumulus cases (Paris: ndays = 563, London: ndays = 549)