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Table S1. Weighted mean turnover times of bulk dissolved organic matter (DOM) in surface and deep waters of the North Atlantic and North Pacific Oceans.
Surface Oceana Deep Oceanb Turnover Turnover Relative Relative Organic and 14C age, A rate 14C age, A rate i contribution of i contribution of size fractions (years B.P.) c constant, (years B.P.) c constant, fraction, Fi -1 d fraction, Fi -1 d ki (year ) ki (year ) Atlantic LE Fractione 8,140 0.0002 1.84E-08 14,250 0.0002 1.40E-08 PL Fractionf 10 0.0200 2.00E-03 1,950 0.0229 1.17E-05 CL Fractiong 5 0.0713 1.43E-02 2,970 0.0338 1.14E-05 MUC Fractionh 230 0.0587 2.55E-04 2,270 0.0430 1.89E-05 LMW Fractioni 2,640 0.8502 3.22E-04 3,890 0.9003 2.31E-04 Sum = 1.68E-02 Sum = 2.74E-04 TOTj = 59 years TOTj = 3,656 years Pacific LE Fractione 6,430 0.0005 7.00E-08 17,100 0.0003 1.75E-08 PL Fractionf 170 0.0285 1.68E-04 3,240 0.0169 5.22E-06 CL Fractiong 5 0.0539 1.08E-02 4,180 0.0411 9.83E-06 MUC Fractionh 1,780 0.0674 3.78E-05 5,550 0.0417 7.51E-06 LMW Fractioni 2,640 0.8503 3.22E-04 6,220 0.9003 1.45E-04 Sum = 1.13E-02 Sum = 1.67E-04 TOTj = 89 years TOTj = 5,977 years aSurface ocean calculations for 3m (Atlantic) and 20m (Pacific) depths. bDeep ocean calculations for 1500m (Atlantic) and 1800m (Pacific) depths. c Relative contributions, Fi, of LE, PL, CL and MUC fractions to DOM are equal to (%LE/100), (%PL/100), (%CL/100) and (%MUC/100), respectively, multiplied by the relative amount of high- molecular-weight DOM, FHMW, in DOM. Percentage contributions of each organic fraction to
DOMHMW are shown in Table 1. DOMHMW was assumed to comprise of 15% of DOM in surface waters and 10% in deep waters. The relative contribution, Fi, of low-molecular-weight (LMW)
DOM to DOM was calculated as FLMW = 1.0 - FHMW.
F d i -1 k i , in year . See Methods section for complete explanation of the calculation. Ai eLE – lipid-extract fraction fPL – protein-like fraction gCL – carbohydrate-like fraction hMUC – molecularly-uncharacterised fraction iLMW – low-molecular-weight fraction, <1,000 Daltons
Loh, Bauer and Druffel (2003-12-13160B) 2
1 j weighted mean turnover time of bulk DOM, TOTDOM , in years. k i
Loh, Bauer and Druffel (2003-12-13160B)