Water is a mercurial subject—at times soothing, at times tumultuous. An endless power hides under the ocean’s surface, making it a popular artistic vision of the sublime, perhaps best exemplified by Romanticist painter J. M. W. Turner’s tempestuous seascapes. Claude Monet’s  Impressionist Water Lilies captured the fleeting effects of sunlight on the calm surfaces of a garden pond. Pop artist David Hockney emphasized the clean lines, flat shapes, and bright colors of California swimming pools. Artists today continue to explore water all its forms, from ice to steam. Roni Horn has created a library of water to house extracts of Icelandic glaciers, photographer Corey Arnold has documented seven winter seasons of raging seas as a commercial fisherman in Alaska, and Maya Lin has transformed grassland into wavelike crests and troughs.