Information about the Gould Data General Information * The floats sampled on the way up. * There is no extrapolation from the first reported position to where the float actually reached the surface. * Information about the float is available in the pcode variables. These include the following. (See the codes list in the documents section.) CSC1 - the name of the originator of the data DDB$ - deployment date DLT$ - deployment latitude DLO$ - deployment longitude Note on calibration of salinity data The salinity data are calibrated using a piece-wise linear fit obtained by comparison of float data with WOCE standard CTD casts (see Bacon, Centurioni and Gould, 2001, J. Atm. Oc. Tech., 18,1258). The correct salinity is obtained with the formula: Snew = Sold + a + bt, where t is the time expressed in number of days. Example (with float 10587): The following table contains the coefficients a and b and their accuracy, the cycle number that corresponds to the calibration point (that is the float profile for which the comparison with a ship-CTD was made) and the corresponding number of days from the deployment of the float. Day Cyc. # a delta-a b delta-b 13 1 0.0116 0.0041 -0.000171 0.000656 27 2 0.0092 0.0051 0.000050 0.000156 180 13 0.0168 0.0188 0.000050 0.000294 263 19 0.0210 0.0056 -0.00033 0.001037 276 20 0.0167 0.0079 0.000052 0.000447 303 22 0.0181 0.0042 0 0 0 23 0 0 0 0 To calibrate profile #1: Snew = Sold + 0.0116 + (-0.000171 * 0) To calibrate profile #2: Snew = Sold + 0.0092 + (-0.000050 * 0) To calibrate profile #3: Snew = Sold + 0.0092 + (-0.000050 * 14) To calibrate profile #4: Snew = Sold + 0.0092 + (-0.000050 * 28) To calibrate profile #13: Snew = Sold + 0.0168 + (-0.000050 * 0) etc … Note that since we calculated a piece-wise linear fit, time is counted in days from the most recent calibration event. That is, if t1 = 13, t2 = 27, t3 = 180, t4 = 263 etc are the days corresponding to the calibration events, to calibrate profile #5 the correct formula is: Snew = Sold + 0.0092 + [-0.000050 * (t2 - t)] This may appear a bit convoluted and impractical but offsetting the time in this way allows you to appreciate quickly the error in salinity (roughly corresponding to a since the drift, b, is always very small). Profiles with cycle number > 22 are uncalibrated. The quality of the data is finally checked by plotting a global T/S diagram (with all the calibrated data from the 4 floats). The points with T~< 3 ° C show that the curve is sufficiently tight to assume that the spread of the points in the plot is due to the natural variability of the water mass we are observing (Labrador Sea Water). Additional salinity calibrations Float number 10588 Day Cyc. # a delta-a b delta-b 12 1 -0.0276 0.0042 0.000024 0.000042 221 16 -0.0225 0.0045 -0.000089 0.000105 303 22 -0.0298 0.0041 0.000013 0.000161 372 27 -0.0289 0.0070 0 0 0 28 0 0 0 0 Float number 10589 Day Cyc. # a delta-a b delta-b 13 1 -0.0306 0.0044 -0.000053 0.000034 303 22 -0.0461 0.0053 0.000279 0.000198 359 26 -0.0305 0.0058 -0.000862 0.000784 372 27 -0.0417 0.0044 0 0 0 28 0 0 0 0 Float number 10591 Day Cyc. # a delta-a b delta-b 12 1 0.0095 0.0044 0.000736 0.000401 40 3 -0.0111 0.0069 -0.000006 0.000057 234 17 -0.0099 0.0041 -0.000067 0.000208 275 20 -0.0126 0.0044 -0.000226 0.000337 302 22 -0.0187 0.0047 0 0 0 23 0 0 0 0 Pressure offsets The pressure data have also been adjusted from the original values. The formula is: Pnew = Pold - offset Absent values for the offset are indicated as -9999 The following tables provide the offsets for each profile for 7 floats. 10587 10588 10589 10590 Offset Profile Number Offset Profile Number Offset Profile Number Offset Profile Number -6 1 -4 1 -9.1 1 1 1 -10.9 2 -16 2 -15.1 2 -6.9 2 -11.9 3 -15 3 -16.1 3 -3.9 3 -11.9 4 -17 4 -15.1 4 -3 4 -11.9 5 -16 5 -16.1 5 -1 5 -11.9 6 -16 6 -16.1 6 -2 6 -11.9 7 -16 7 -16.1 7 0 7 -11.9 8 -16 8 -16.1 8 -2 8 -11.9 9 -17 9 -16.1 9 0 9 -11.9 10 -17 10 -16.1 10 -2 10 -11.9 11 -16 11 -16.1 11 0 11 -12.9 12 -16 12 -16.1 12 -1 12 -11.9 13 -16 13 -16.1 13 -1 13 -11.9 14 -16 14 -16.1 14 -1 14 -10.9 15 -15 15 -16.1 15 0 15 -10.9 16 -15 16 -15.1 16 0 16 -10.9 17 -16 17 -14.1 17 0 17 -10.9 18 -15 18 -13.1 18 0 18 -9.9 19 -14 19 -13.1 19 0 19 -9.9 20 -14 20 -13.1 20 1 20 -9.9 21 -14 21 -12.1 21 1 21 -9.9 22 -14 22 -12.1 22 1 22 -9.9 23 -14 23 -13.1 23 1 23 -9.9 24 -15 24 -13.1 24 1 24 -9.9 25 -16 25 -14.1 25 1 25 -9.9 26 -16 26 -15.1 26 1 26 -10.9 27 -16 27 -15.1 27 1 27 -12.9 28 -16 28 -15.1 28 0 28 -13.9 29 -17 29 -15.1 29 0 29 -12.9 30 -17 30 -16.1 30 0 30 -11.9 32 -17 31 -16.1 31 0 31 -11.9 33 -17 32 -16.1 32 -1 32 -11.9 34 -17 33 -1 33 -10.9 36 -16 34 -1 34 -10.9 37 -17 35 -1 35 -10.9 38 -17 36 -1 36 -9.9 39 -17 37 -1 37 -8.9 40 -17 38 -1 38 -9.9 41 -17 39 0 39 -8.9 42 -17 40 0 40 -7.9 43 -19 41 0 41 -7.9 44 -18 42 1 42 -6.9 45 -19 43 1 43 -6.9 46 -17 44 1.9 44 -6.9 47 -16 45 1 45 -7.9 48 -15 46 1.9 46 -7.9 49 -14 47 1.9 47 -7.9 50 -15 48 1 48 -7.9 51 -14 49 1 49 -8.9 52 -14 50 1 50 -7.9 53 -14 51 1 51 -8.9 54 -15 52 1 52 -8.9 55 -16 53 0 53 -8.9 56 -17 54 0 54 -8.9 57 -17 55 0 55 -8.9 58 -18 56 0 56 -7.9 59 -18 57 0 57 -7.9 60 -18 58 0 58 -8.9 61 -17 60 0 59 -7.9 62 -18 61 0 60 -6.9 63 -16 62 1 61 -6.9 64 -16 63 0 62 -6.9 65 -16 64 1 63 -6 66 -16 65 0 64 -6 67 -16 66 1 65 -3 68 -15 67 1 66 -3 69 -14 68 1 67 -2 70 -11 69 1 68 -2 71 -9 70 0 69 -1 72 -11 71 1 70 -2 73 -9 72 1 71 -2 74 -9 73 1 72 -3 75 -9 74 1.9 73 -3 76 -5 75 1 74 -5 77 -6 76 1 75 -6 78 -6 77 0 76 -6 79 -7 78 1 77 -6.9 80 -8 79 0 78 -6.9 81 -9 80 0 79 -6.9 82 -8 81 0 80 -7.9 83 -9 82 -1 81 -6.9 84 -9 83 0 82 -7.9 85 -9 84 -2 83 -6.9 86 -9 85 -2 84 -6.9 87 -9 86 -1 85 -7.9 88 -9 87 -2 86 -6.9 89 -10 88 -2 87 -6.9 90 -9 89 -2 88 -4 91 -10 90 -1 89 -6 92 -8 91 -2 90 -6 93 -8 92 -2 91 -2 94 -11 93 -2 92 -1 95 -9 94 -1 93 -1 96 -10 95 -1 94 -1 97 -9 96 -1 95 -1 98 -9999 97 0 96 -1 99 -6 98 -1 97 -1 100 -7 99 -1 98 -1 101 -8 100 -1 99 0 102 -7 101 -1 100 -1 103 -8 102 -3 101 -1 104 -9 103 -3.9 102 -1 105 -9 104 -4.9 103 -1 106 -9 105 -6.9 104 -1 107 -9 106 -7.8 105 0 108 -9 107 -7.8 106 -1 109 -9 108 -8.8 107 -1 110 -9 109 -8.8 108 0 111 -10 110 -9.8 109 0 112 -10 111 -10.8 110 -1 113 -10 112 -10 113 -9 114 -10 115 -9 116 -8 117 -8 118 -7 119 -6 120 10591 10592 10593 Offset Profile Number Offset Profile Number Offset Profile Number -4.9 1 -5.9 1 -3.1 1 -5.9 2 -9.9 2 -8.3 2 -8.9 3 -12.9 3 -8.3 3 -12.9 4 -7.3 4 -13.9 5 -7.3 5 -12.9 6 -9.3 6 -13.9 7 -9.3 7 -13.9 8 -8.3 8 -13.9 9 -8.3 9 -12.9 10 -8.3 10 -12.9 11 -7.3 11 -11.9 12 -7.3 12 -11.9 13 -7.3 13 -11.9 14 -7.3 14 -10.9 15 -6.2 15 -10.9 16 -6.2 16 -10.9 17 -5.2 17 -8.9 18 -4.1 18 -8.9 19 -3.1 19 -7.9 20 -2 20 -8.9 21 -2 21 -7.9 22 -2 22 -7.9 23 -2 23 -7.9 24 -2 24 -8.9 25 -2 25 -8.9 26 -2 26 -8.9 27 -2 27 -8.9 28 -2 28 -8.9 29 -3.1 29 -8.9 30 -3.1 30 -3.1 31 -4.1 32 -4.1 33 -4.1 34 -4.1 35 -4.1 36 -3.1 37 -3.1 38 -3.1 39 -3.1 40 -2 41 -1 42 0 43 0 44 2.1 45 2.1 46 3.2 47 2.1 48 2.1 49 2.1 50 3.2 51 3.2 52 2.1 53 2.1 54 1.1 55 1.1 56 0 57 1.1 58 0 59 1.1 60 1.1 61 1.1 62 1.1 63 1.1 64 2.1 65 2.1 66 3.2 67 3.2 68 3.2 69 3.2 70 4.2 71 4.2 72 6.3 73 6.3 74 6.3 75 5.3 76 5.3 77 5.3 78 5.3 79 5.3 80 5.3 81 4.2 82 4.2 83 4.2 84 6.3 85 5.3 86 5.3 87 5.3 88 6.3 89 6.3 90 6.3 91 6.3 92 7.3 93 7.3 94 8.4 95 8.4 96 10.5 97 9.4 98 10.5 99 10.5 100 10.5 101 9.4 102 10.5 103 9.4 104 9.4 105 8.4 106 8.4 107 8.4 108 8.4 109 8.4 110 8.4 111 8.4 112 8.4 113 8.4 114 8.4 115 8.4 116 9.4 117 9.4 118 9.4 119 10.5 120 -9999 121 11.5 122 12.6 123 12.6 124 12.6 125 12.6 126 12.6 127