TY  - JOUR
TI  - Excess radiocarbon constraints on air-sea gas exchange and the uptake of CO2 by the oceans
JF  - Geophysical Research Letters
N2  - We re-assess the constraints that estimates of the global ocean excess radiocarbon inventory place on air-sea gas exchange. We found that the gas exchange scaling parameter aq cannot be constrained by the excess radiocarbon inventory alone. Non-negligible biases in different global wind speed datasets require a careful adaptation of aq to the wind field chosen. Furthermore, aq depends on the spatial and temporal resolution of the wind fields.  We develop a new wind speed- and inventory-normalized gas exchange parameter aqN which takes into account these biases and which is easily adaptable to any new estimate of the ocean excess radiocarbon inventory. Our study yields an average estimate of aq of 0.32+/-0.05 for monthly mean winds, lower than the previous estimate (0.39) from Wwanninkhof (1992). We calculate a global annual average piston velocity for CO2 of (16.7+/-2.9) cm/hr and a gross CO2 flux between atmosphere and ocean of (73+/-10) PgC/yr, significantly lower than results from previous studies.
VL  - 33
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/6713/
Y1  - 2006///
AV  - public
ID  - heidok6713
KW  - Gasaustausch 
KW  -  Radiokohlenstoffgas exchange 
KW  -  radiocarbon 
KW  -  carbon cycle
A1  - Naegler, Tobias
A1  - Ciais, Philippe
A1  - Rodgers, Keith
A1  - Levin, Ingeborg
N1  - L11802, doi:1029/2005GL025408 
ER  -