SIMON: The operational cycle goes like this.Each ofthe floats is dropped in the ocean from a boat at aset point and activated from a satellite.Then the floatimmediately sinks about 2,000 metres...that's twowhole kilometres down in the water.It stays at thisdepth for about days and is carried around by thecurrents which operate in the ocean at thislevel.During this time it's possible for it to coverquite large distances but the average is fiftykilometres.
STUDENT 2: So what is it actually recording?
SIMON: Well at this stage nothing,but as it rises to the surface it collects all sorts of data,mostimportantly variations in salinity,that's salt levels,and the changes in temperature,a bit likeunderwater weather balloons.Then when it gets back to the surface all the data it's collected isbeamed up to the satellite.After about five hours on the surface the float automaticallysinks,beginning the whole process again.
STUDENT 1: What happens to the data?
SIMON: Well the information is transferred direct to onshore meteorological stations...like ourone in Hobart...and within four hours the findings can be on computers and they can bemapped and analysed.