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Global Magnetic Drifter Pilot Project

Data format

The APS magnetic sensor made a measurement for 128 seconds every 20 minutes. Those 128 samples were averaged into one value of X,Y and Z magnetic field value. Every 4 hours the data were sent via Iridium to the Argo drifter database website

Once a day (every 24 hrs) a calibration cycle was run where 256 sequential raw data values were recorded. The data fields are ascii with an identifying first character to describe the type of data.

S: status line

S 000000000066760 123 270 2011.08.13 23:03:06 47.651360 -129.042221 8

S drifter_id rec_# day date time latitude longitude ?

M: measurement

M 1 -62475.9 -32540.4 -10721.9 19.39 47.9019 -128.9508 1.6 2011 224.80556 17.49

M meas_# xf yf zf temperature latitude longitude ? yr decimal_julian _day

E:

E 12.7 0

E battery_voltage ?

C: Calibration header

C 8 2011 225.12518

C id yr decimal_julian_day

c: calibration measurement


data snippet


S 000000000066760 123 270 2011.08.13 23:03:06 47.651360 -129.042221 8
M  1   -62475.9   -32540.4   -10721.9   19.39   47.9019  -128.9508   1.6 2011  224.80556 17.49
M  2   -62149.4   -32226.8   -10609.6   19.43   47.8619  -128.9498   1.0 2011  224.81944 17.27
M  3   -62421.8   -32850.4   -10549.6   19.51   47.8224  -128.9495   1.9 2011  224.83333 17.27
M  4   -62947.0   -33441.8   -10522.6   19.46   47.7834  -128.9499   1.6 2011  224.84723 17.37
M  5   -62645.0   -33261.3   -10306.0   19.86   47.7435  -128.9506   1.0 2011  224.86111 17.66
M  6   -61973.9   -32076.1   -10387.2   20.56   47.7046  -128.9503   1.0 2011  224.87500 17.64
M  7   -62114.1   -32533.0   -10342.7   20.15   47.6654  -128.9503   1.0 2011  224.88889 17.32
M  8   -32815.3   -42382.6    31311.9   19.62   47.6257  -128.9497   9.9 2011  224.90320 17.39
M  9   -31184.2   -42279.9    31509.2   17.91    0.0000     0.0000   0.0 2011  224.91708 17.24
M 10   -45160.4   -50575.0    39316.0   16.88   47.5499  -128.9567   7.4 2011  224.93097 16.96
M 11   -40946.5   -76445.5    39887.3   16.53    0.0000     0.0000   0.0 2011  224.94485 17.00
M 12   -41006.2   -75652.7    39661.8   16.64   47.6047  -129.0018   4.2 2011  224.95872 17.12
E  12.7     0
S 000000000066760 124 268 2011.08.14 03:02:21 47.946709 -129.119843 4
C   8 2011  225.12518
c 233   -27366.5   -76053.9    14041.0   17.27
c 234   -27193.7   -75863.6    13992.4   17.27
c 235   -25388.9   -77275.0    14923.7   17.27
c 236   -21542.5   -79203.1    16757.6   17.27
c 237   -23558.5   -81968.0    17548.2   17.27
c 238   -22028.9   -75012.1    14805.1   17.27
c 239   -19353.7   -71871.7    14504.2   17.27
c 240   -17910.5   -70902.9    14708.6   17.27
c 241   -17443.3   -74650.7    16259.2   17.27
c 242   -18313.7   -74747.0    15952.4   17.27
c 243   -19878.5   -72758.9    14633.6   17.27
c 244   -24924.9   -74086.3    13708.0   17.27
c 245   -16604.9   -76572.9    17397.1   17.59
c 246   -21436.9   -75726.1    15272.2   17.59
c 247   -20259.3   -72515.8    14418.2   17.59
c 248   -18604.9   -76481.5    16556.9   17.59
c 249   -20592.1   -74784.2    15167.7   17.59
c 250   -17628.9   -71157.0    14911.4   17.59
c 251   -22889.7   -77703.1    15707.4   17.59
c 252   -20086.5   -73319.6    14772.8   17.59
c 253   -16953.7   -70584.4    15005.5   17.59
c 254   -19488.1   -73028.8    14866.7   17.59
c 255   -13804.9   -63347.5    14500.1   17.59
c 256   -16940.9   -64388.0    13245.8   17.34
S 000000000066760 125 323 2011.08.14 03:03:29 47.942814 -129.044510 8
C   7 2011  225.12518
c 204   -35148.9   -77591.9    14191.4   16.95
c 205   -40998.5   -73769.4    13098.5   16.95
c 206   -39830.5   -74034.4    13034.3   16.95
c 207   -47622.5   -69247.5    12978.6   16.95
c 208   -49222.5   -68372.8    13234.5   17.27
c 209   -37699.3   -74434.2    12976.9   17.27
c 210   -38915.3   -82531.2    16941.2   17.27
c 211   -35740.9   -77267.5    14070.3   17.27

"Doc" and "Happy" remain on shore for the present time

"Sneezy", "Bashful" and "Grumpy" have stopped working as of 6/13/13

"Dopey" stopped working 8/9/13

"Sleepy" stopped working 10/4/13

 

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