The subtropical plankton in Arctic waters are likely the result of an isolated pulse of water that carried them outside their natural habitat, say scientists.
Bjorklund et al., Jnl Micropalaeontology 2012
This may sound like a story about the surprising effects of global warming, but it isn't. At least not entirely.
That's because the researchers believe these warm-water invaders, called Radiolaria, are likely the result of an isolated pulse of water that carried them beyond the usual extent of the northbound Gulf Stream, a current that travels from the Gulf of Mexico into the northern Atlantic Ocean.
In 2010, a ship operated by the Norwegian Polar Institute collected plankton samples northwest of the Norwegian archipelago of Svalbard in the Arctic Ocean. Of the 145 types of organisms in these samples, 98 came from farther south, as far as the tropics.