Summary of Data Presented

The data presented in this report are from PMEL cruises conducted in the Pacific and Indian Oceans during 1986-1989. The data files provide a complete listing of the calculated fugacities, the warming-corrected mole fraction CO2 concentrations, and the data required to convert between in situ mole fraction and fugacity.

The fugacities were calculated according to equations given in Murphy et al. (1994). The fugacity calculations use observations of dry gas concentrations in units of parts per million, sea surface temperature, equilibrator temperature, sea surface salinity, and atmospheric pressure. The relative humidity is assumed to be 100% at the sea surface. The vapor pressure of seawater is calculated from temperature and salinity, and the functional relationship between gas solubility and temperature used is from Weiss et al. (1982). The fugacity values given in the data files are the in situ fugacities which have been corrected for the warming of the seawater in transiting to the equilibrator.

The mole fraction values given in the data files are the dry gas concentrations at the in situ temperature. For the air values, the reported concentration, X(CO2)air, is the mole fraction of the dried air pumped from the bow line. For the water values, the reported concentration, X(CO2)sw, is the mole fraction of the dried vapor drawn from the equilibrator headspace which has been converted to fugacity, corrected for warming, and converted back to mole fraction.

The warming values provided in the data files indicate the degrees of warming (°C) for seawater as it transited from the intake line to the analysis site. The warming values were derived from the regression of hourly warming on hourly sea surface temperature. Detailed information on the temperature data and analyses for each of these cruises are provided in Murphy et al. (1993).

Table 2 presents statistics on the fugacity of CO2 in the atmosphere [f(CO2)air] and in the surface seawater [f(CO2)sw] for each leg of the PMEL 1986-1989 cruises. All maximums and minimums for f(CO2)air and f(CO2)sw, their sample locations, and dates are given. Highlighted values indicate maximum of maximums and minimum of minimums for fugacities of CO2 for the 12 PMEL legs.

Table 2. Statistics on the fugacity of CO2 in the atmosphere [f(CO2)air] and in surface seawater [f(CO2)sw] for each leg of the PMEL cruises from 1986-1989.

Cruise Section EPOCS 1986 RITS/CO2 1986 SAGA II 1987 Transit SAGA II 1987, Leg 1 SAGA II 1987, Leg 2 TEW-3 1987 RITS/CO2 1987 RITS/CO2 1988 EPOCS 1988 RITS/CO2 1989, Leg 1 RITS/CO2 1989, Leg 2 RITS/CO2 1989, Leg 3
DATA
f(CO2)air maximum 337.26 350.90 357.25 353.06 349.87 338.28 343.21 357.39 345.71 351.82 352.80 349.93
Distance (km) 12,171.9 1,466.1 2,460.2 358.0 2,927.2 2,204.0 7,050.4 276.8 8,246.7 5,133.6 7,521.8 7,752.9
Latitude (dec.deg.) 18.312 16.010 38.373 45.772 -39.250 -1.448 51.263 50.050 15.433 -11.878 -45.027 48.193
Longitude (dec.deg.) -155.435 -146.308 175.059 158.333 142.383 165.123 -169.747 -170.040 -148.083 -104.997 -129.985 -124.939
Day (GMT) 170.333 186.375 128.417 138.208 168.250 203.208 232.875 99.708 154.375 56.375 85.250 110.250
f(CO2)air minimum 330.95 336.60 345.42 329.10 331.99 331.35 329.70 332.22 333.19 335.74 329.44 334.12
Distance (km) 9,099.7 965.0 2,305.0 3,961.8 10,284.0 2,748.5 3,636.6 8,269.4 113.1 3,608.1 4,142.9 1,814.5
Latitude (dec.deg.) -2.067 19.500 37.556 -8.333 -7.783 1.993 38.022 -11.033 -12.583 -1.012 -60.065 -1.835
Longitude (dec.deg.) -139.983 -149.300 176.444 166.433 90.000 165.008 165.000 -170.097 -170.500 -109.973 -105.585 -140.017
Day (GMT) 164.042 185.542 128.042 151.167 181.375 205.708 223.417 126.125 132.208 53.083 74.167 101.125
f(CO2)sw maximum 434.59 377.72 409.09 411.98 407.93 352.77 415.96 448.00 450.52 480.93 392.98 440.37
Distance (km) 138.0 4,195.0 4,314.9 318.0 10,284.0 1,895.2 7,248.2 6,901.8 5,817.5 3,956.6 553.8 1,806.2
Latitude (dec.deg.) 0.520 34.057 47.600 45.500 -7.783 -3.563 53.015 0.420 2.617 -4.003 -29.157 -1.825
Longitude (dec.deg.) -91.772 -135.007 156.367 158.317 90.000 164.987 169.292 -169.930 -140.033 -110.008 -105.012 -139.993
Day (GMT) 144.042 192.833 131.500 137.750 181.375 201.833 233.167 122.000 147.542 53.792 65.167 101.000
f(CO2)sw minimum 338.08 286.03 214.77 267.61 292.73 310.55 247.56 291.60 321.86 337.96 234.10 252.53
Distance (km) 11,303.9 7,545.7 4,368.6 1,098.6 5,675.8 0.0 7,592.4 2,914.7 397.8 1,648.0 4,618.3 7,692.9
Latitude (dec.deg.) 12.842 54.530 47.983 34.734 -33.866 -12.533 53.200 32.000 -10.050 14.362 76.833 47.927
Longitude (dec.deg.) -149.895 -145.002 155.945 160.066 112.542 153.215 -165.330 -170.100 -170.300 -104.932 -60.562 -125.097
Day (GMT) 168.917 202.750 131.958 140.833 173.292 195.833 235.000 108.917 132.625 47.833 76.833 110.125
Mean % stand. dev. for the standard gases <1% <0.7% 0.24% 0.24% 0.24% 0.32% 0.32% 0.60% 0.21% 0.37% 0.37% 0.37%

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