Stratocumulus clouds cover about 20% of Earth’s surface at any given time, and they form distinctive patterns of lumpy cells separated by thin slits. Because of their interconnectedness, researchers nicknamed these narrow regions spiderwebs. New simulations show that evaporative cooling along the cloud tops drives the formation of these spiderwebs (Image 2). Without it (Image 3), the cloud pattern looks very different. (Image credits: featured image – L. Dauphin/MODIS, others – UConn ME 3250; research credit: G. Matheou et al.)