"Think about it like a layer cake," says Osborn. A recent study in shallow waters found that while dropstones covered less than 1 percent of the ocean floor, they harbored about 20 percent of seafloor life. Not only do icebergs sprinkle nutrients into ocean waters, they also drop chunks of rock termed glacial dropstones. It's not clear what happens to those microbes when the icebergs melt. When icebergs head out to sea they carry cryoconites, pockets of minerals and microbes from windblown dust and ocean spray. The National Oceanic and Atmospheric Administration calls smaller fragments (roughly the size of a grand piano or maybe a small truck) “growlers.” Smaller ice chunks not quite grand enough to be dubbed icebergs are called “bergy bits,” with heights from 3 to 16 feet. Icebergs come in a vast range of sizes, from areas slightly smaller than a softball infield to nearly the size of Connecticut. "You have this big chunk of iron floating around out there and you get this big intense growth and you can actually see it," says Karen Osborn, a research zoologist at the Smithsonian's National Museum of Natural History who studies how marine invertebrates adapt to challenging environments.īergy bits and dropstones: Icy terms from icebergs These minerals fertilize the tiny photosynthetic plankton that live off sunlight and form the foundation of the marine food web. As ocean currents carry the berg through its life, it slowly melts, sprinkling iron and other nutrients into the waters around it. By the time a chunk of glacier falls into the sea, it is packed with minerals and nutrients from the land - and this enshrined rubble is one way icebergs transform the oceans. These sediments paint the walls of some glaciers (and icebergs) with dark stripes. A peppering of airborne particles settle on the ice, becoming trapped by new layers of falling snow. In slow motion, these rivers flow, churning up and entrapping masses of rock and soil as they grind across the land. They begin as pieces of glaciers - thousands of years of snowfall compacted into mountainous rivers of ice. Icebergs are commonly thought of as creatures of the oceans, but in fact they are born on land. The massive and mysterious habitats they create are realms scientists have only just begun to understand. Much more than cold, lifeless killers, they are wandering, dynamic islands - promoting marine life, sucking carbon dioxide from the air and changing as they traverse the seas. Carrying nutrients from land and sometimes reaching the size of small US states, they drive blooms of life that influence the carbon cycle, as shown in the diagram above. Anonymously uploaded and probably designed to self-erase once they’ve served their function, these pictures are not traceable or visible on the surface web, and only exist temporarily in this dark, secret space on the deep web.As they slowly see-saw and spin through polar currents, icebergs fertilize the oceans. Unlike the stock pictures, these original photographs are invisible in The Iceberg under normal light: printed in invisible ink, they can only be viewed under ultraviolet light – the same light drug enforcers use to look for traces of narcotics. The original photographs, probably taken with small cameras or smartphones, often look surreal and abstract due to the mysterious, exotic aesthetic of the subject-matter, on the one hand, and the low quality of the photos or inferior skills of the drug-pushing photographers themselves, on the other. The Iceberg features a selection of stock images and original photographs drawn from the myriad ads for drug sales on the dark web designed to catch the consumer’s eye. This darknet is a lawless no-man’s land, only accessible using specific software, where anything goes and nothing is traceable, and where illicit online business, especially in contraband, proliferates. Under the surface web that we use day in, day out, lies an encrypted and constantly evolving network of total anonymity, beyond the reach of search engines. The submerged part, roughly 90% of the iceberg, is the so-called deep web. The Internet can be regarded as an iceberg: the tip is the so-called surface web, the digital terrain we know and surf by means of search engines, social networks, blogs and news sites.
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