© NASA/GSFC/JPL-Caltech
Among the prominent salinity features visible in this view are the large area of highly saline water across the North Atlantic. This area, the saltiest anywhere in the open ocean, is analogous to deserts on land, where little rainfall and much evaporation occur. Red colors represent areas of high salinity, while blue shades represent areas of low salinity.
The salinity level of the world's rivers, lakes and oceans has been a growing topic in response to global climate change. As NASA's
Aquarius instrument has shown previously, seasonal salinity has been on the rise in oceans all around the world. This year, the picture is no less striking, with deep shades of oranges and reds, at least in the image above, filling a large swath of the Atlantic Ocean both to the north and to the south of the equator.
Launched on June 10, 2011 aboard the Argentine spacecraft SAC-D, Aquarius was specifically developed to study the salt content of the oceans' surface waters. Variations in ocean salinity, one of the main drivers of ocean circulation, are closely associated with the cycling of freshwater around the world. The data collected from these measurements provide scientists with valuable information on how global climate change is affecting rainfall patterns around the globe.
"With a bit more than a year of data, we are seeing some surprising patterns, especially in the tropics," said Aquarius' principal investigator Gary Lagerloef, of
Earth & Space Research in Seattle, Washington. "We see features evolve rapidly over time."
Aquarius was designed to cover the Earth from an orbit that takes it over all the world's ice-free oceans, taking a complete measurement of salinity levels every seven days. The detector on the instrument measures the top 1 inch of ocean water in 240-mile-wide swaths as it sweeps across the world overhead.
NASA has now received its first full year worth of data from Aquarius showing the varying salinity patterns around the globe.
Comment: From the BBC: