The Argo project has reached a milestone of 3,000 robots. These robots monitor ocean temperatures and salinity.

The cylindrical robot descends to a depth of 2,000 meters and drifts with the current for 9 days. the robot then rises to the surface, while gathering data. Once at the surface it transmits the data via satellite to weather centers.

The robot then descends to 2,00 meters again and repeats the process. The robots have been deployed in all of the major oceans. How they avoid surfacing into or damaging boats we are not sure, but next time you are swimming in the ocean, watch out for the robots.

Many countries such as France, China, Norway and the United States participate in this program.

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