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Float of the Month (September)

This is going to be an irregular (but maybe monthly) post on interesting floats.  And it will be replicated, within 280 characters at my Twitter feed @Kenatmbari.

The first twitter post was back in September. Here it is:

"BGC-Argo float of the month. 5903248 has gone 3/4 of the way around the world, generating beautiful oxygen data down to 2000 meters. Launched by Argo Australia (Susan Wijffels, Argo Co-Chair is PI) in 2010, it is still reporting after more than 9 years."

Note, while Susan Wijffels was PI, Tom Trull at CSIRO was also heavily involved in adding the oxygen sensor.  You can access the data file for this float at the following link (works in Chrome, not Firefox, or use an FTP client):

ftp://ftp.ifremer.fr/ifremer/argo/dac/csiro/5903248/5903248_Sprof.nc

The Sprof.nc file (these are the files most useful) contains both the raw data and data adjusted for errors in the sensor calibration (a common issue referred to as storage drift - sensors drift a lot when stored in the air, but very little when deployed in water).  The raw data runs to the present, while adjusted data has only been updated to mid-2018. The graphic shows the trajectory as the float circled the Southern Ocean, a vertical section of of oxygen percent saturation versus time, surface (upper 20 m) oxygen percent saturation versus time (computed with the adjusted oxygen), and the raw surface oxygen values to illustrate the complete record.  The consistency of the annual cycles of surface percent saturation around 100% demonstrates the stability of the sensor.

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