p24cfc.notes EXTRACTED FROM 9511cfc.doc Blanks Sample blanks of F-11 and F-12 for each bottle were obtained before and after the observations along the P24 section, at 2500 m depth of Sta. Rf0068(31-25N,133-03E; 1995/11/16) and Rf0095(25-49N,129-49E; 1995/11/27). The results are shown in Figure 2. The mean and standard deviation of F-11/F-12 blanks are approximately 0.02+/-0.005 pmol/kg, and no bottle seriously contaminated was found. During the observation, samples drawn from the deepest bottle were analyzed to monitor contamination of the system. The results (Table 3) shows that the system was not seriously contaminated during the observation. Sample blanks which should be subtracted from measurement values are determined so that F-11/F-12 concentrations are zero below 2000 m depth at each station. The values are shown in Table 4. Table 2: Sample blanks at the test stations. (1) Before P24 section Stn. Bottle Syringe Depth F12 F11 (m) (pmol/kg) (pmol/kg) -------------------------------------------------------- Rf0068 1 1 2500 0.030 0.028 Blank 2 2 2500 0.019 0.029 Test 3 3 2500 0.036 0.037 4 4 2500 0.023 0.025 5 5 2500 0.032 0.025 6 6 2500 0.014 0.028 7 7 2500 0.024 0.030 8 8 2500 0.025 0.030 9 9 2500 0.027 0.021 10 10 2500 0.027 0.028 18 18 2500 0.020 0.022 19 19 2500 0.021 0.024 11 11 2500 0.020 0.026 12 12 2500 0.021 0.031 13 13 2500 0.021 0.022 15 15 2500 0.019 0.023 14 14 2500 0.026 0.029 16 16 2500 0.015 0.023 17 17 2500 0.021 0.024 20 20 2500 0.014 0.022 21 21 2500 0.023 0.023 22 22 2500 0.011 0.023 23 23 2500 0.023 0.024 24 24 2500 0.018 0.038 -------------------------------------------------------- MEAN 0.022 0.026 S.D. 0.006 0.005 -------------------------------------------------------- Table 2.(continued) (2) After P24 section Stn. Bottle Syringe Depth F12 F11 (m) (pmol/kg) (pmol/kg) -------------------------------------------------------- Rf0095 1 1 2500 0.017 0.014 Blank 2 2 2500 0.008 0.014 Test 3 3 2500 0.013 0.014 4 4 2500 0.014 0.019 5 5 2500 0.012 0.016 6 6 2500 0.013 0.016 7 7 2500 0.013 0.015 8 8 2500 0.011 0.014 9 9 2500 0.019* 0.024* 10 10 2500 0.013 0.016 11 11 2500 0.017 0.018 12 12 2500 0.015 0.018 13 13 2500 0.011 0.014 14 14 2500 0.010 0.012 15 15 2500 0.012 0.014 16 16 2500 0.010 0.014 17 17 2500 0.031 0.026 18 18 2500 0.016 0.014 19 19 2500 0.018 0.017 20 20 2500 0.014 0.015 21 21 2500 0.014 0.014 22 22 2500 0.013* 0.029* 23 23 2500 0.014 0.021 27 24 2500 0.023* 0.027* -------------------------------------------------------- MEAN 0.015 0.017 S.D. 0.005 0.005 -------------------------------------------------------- * : bad measurement Table 3: Sample blanks of the deepest bottles. -------------------------------------------------- Stn. Cast Bottle Depth F12 F11 (m) (pmol/kg) (pmol/kg) -------------------------------------------------- Rf0072 1 1 2058 0.019 0.038 P24-04 Rf0074 1 1 3909 0.017 0.030 P24-06 1 3909 0.029 0.035 Rf0076 1 1 4833 0.010 0.021 P24-08 24 4834 0.017 0.023 1 4833 0.023 0.027 24 4834 0.016 0.023 Rf0077 1 1 5009 0.023 0.026 P24-09 1 5009 0.029 0.022 1 5009 0.026 0.025 1 5009 0.023 0.020 Rf0078 1 1 4152 0.019 0.025 P24-10 1 4152 0.022 0.022 Rf0082 1 1 4290 0.017 0.022 P24-14 RF0084 1 1 4881 0.022 0.029 P24-16 1 4881 0.020 0.022 1 4881 0.018 0.017 Rf0085 1 1 5164 0.020 0.025 P24-17 Rf0091 1 1 5376 0.027 0.034 P24-23 Rf0093 1 1 4170 0.018 0.024 P24-25 1 4170 0.016 0.025 -------------------------------------------------- Table 4: Sample blanks determined at each station. Stn. F-12 F-11 \374ipmol/kg)\374ipmol/kg) ---------------------------------- RF0070 (P24-02) 0.019 0.038 RF0072 (P24-04) 0.019 0.038 RF0074 (P24-06) 0.018 0.027 RF0078 (P24-10) 0.011 0.026 RF0082 (P24-14) 0.016 0.016 RF0085 (P24-17) 0.025 0.020 RF0088 (P24-20) 0.008 0.019 RF0091 (P24-23) 0.013 0.031 RF0093 (P24-25) 0.009 0.023 ---------------------------------- Precision The reproducibility was estimated from replicate analyses of 100-500m depths water at 8 stations (Table 5). It was approximately less than 2 % for F-11 and F-12, but at two stations (Rf0085 and Rf0091) the F-12 differences showed extraordinary large values. Table 5: Reproducibility estimated by replicate analyses. Stn. Cast Bottle Syringe Depth F-12 F-11 F12 Diff F11 Diff (m)\374ipmol/kg) (pmol/kg) \374i\374\364\374j \374i\374\364) ------------------------------------------------------------------------ Rf0072 1 9 9 805 0.208 0.430 5.15 0.93 P24-04 9 9 805 0.219 0.434 1 15 15 200 1.291 2.364 0.08 0.30 15 15 200 1.292 2.357 1 20 20 49 1.061 1.886 3.43 0.79 20 20 49 1.098 1.901 Rf0074 2 6 14 204 1.292 2.385 0.54 0.38 P24-06 6 14 204 1.299 2.376 Rf0078 2 6 14 201 1.187 2.119 0.59 0.43 P24-10 6 14 201 1.180 2.110 2 8 16 101 1.090 1.791 2.23 1.86 8 16 101 1.066 1.758 Rf0082 1 13 4 1768 0.004 0.008 \374@\374@- - P24-14 13 4 1768 0.000 0.006 2 13 20 5 1.111 1.895 1.00 0.47 13 21 5 1.100 1.904 2 6 14 203 1.359 2.486 1.04 0.81 6 15 203 1.345 2.466 Rf0085 1 6 14 202 1.297 2.525 0.46 14.71 P24-17 6 15 202 1.291 2.179 Rf0088 2 6 14 203 1.365 2.458 0.66 2.68 P24-20 6 15 203 1.356 2.393 Rf0091 2 6 16 201 1.373 2.640 1.10 13.59 P24-23 6 17 201 1.358 2.304 2 3 12 504 0.941 1.708 2.04 1.89 3 13 504 0.922 1.676 2 13 21 7 1.073 1.596 0.84 5.60 13 21 7 1.082 1.688 Rf0093 1 19 13 504 1.069 2.048 0.00 1.65 P24-25 19 14 504 1.069 2.082 1 21 16 201 1.311 2.224 1.77 4.08 21 17 201 1.288 2.135 ------------------------------------------------------------------------ Air Sampling At 25-39'N, 131-11'E after the observations along the P24 section, on November 26 of 1995, we took marine air samples with a 300 cc syringe and injected them in the system to analyze CFCs. The results are shown in Table 6 with the CFCs concentration of the laboratory air simultaneously analyzed. Table 6: Air measurements at 25-39'N,131-11'E F12 F11 Nov. 26, 1995 (ppt) (ppt) ----------------------------------------------- the open air 557.7 284.0 569.4 286.4 556.7 281.6 570.8 297.2 the air inside ship 582.2 426.1 (in the laboratory) 571.1 360.1 ----------------------------------------------- Standard Gas A standard gas used in our cruise was made by Nippon Sanso Inc. Concentrations of F-11 and F-12 contained in our standard gas were calibrated by Dr. Yutaka Watanabe of National Reserch Institute for Resources(NIRE) on October 25, about twenty days before the WHP-P24 observations. F-11 and F-12 concentrations of our standard gas referred to a NIRE standard gas were 288.0+/-2.8 pptv and 482.4+/-5.7 pptv, respectively. We used these values to calculate the F-11 and F-12 concentrations of seawater/air samples obtained during the cruise. The NIRE standard gas has been scaled by a SIO standard gas used in the Hokkaido University. Therefore, our values determined via NIRE standard gas ought to have consistency with data scaled with SIO standards.