Scientists Plot Sea Levels Using GPS Satellites (engadget.com)
A team from the UK's National Oceanography Centre (NOC), University of Michigan and NASA's Jet Propulsion Laboratory have discovered a new way to accurately measure the sea level. The technique is called GNSS-R, and involves bouncing low-powered signals from GPS satellites off of the ocean's surface and measuring the reflected signal with a GNSS-R receiver. The team used a research satellite launched last year as a GNSS-R receiver, but it will be able to tap a new constellation of receivers that NASA is launching this year as part of CYGNSS. That mission will make accurate measurements of surface winds using GPS satellites, but NOC scientists will be able to use them to measure ocean levels, too, yielding a thirty-fold increase in such data.
The question is, what will happen if the satellite data disagrees with the terrestrial data?
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