Auxiliary material for
Calcium carbonate dissolution in the upper 1000 m of the eastern North Atlantic
Pamela M. Barrett1,2, Joseph A. Resing2, Nathaniel J. Buck2, Richard A. Feely3, John L.
Bullister3, Clifton S. Buck4,5, William M. Landing4
1
School of Oceanography, Box 357940, University of Washington, Seattle, WA 98195, USA
Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Box
354235, Seattle, WA 98195, USA
3
NOAA-Pacific Marine Environmental Laboratory, 7600 Sand Point Way NE, Seattle, WA
98115, USA
4
Department of Earth, Ocean, and Atmospheric Science, Florida State University, 117 N.
Woodward Avenue, Tallahassee, FL 32306, USA
2
5
Now at Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, GA, 31411, USA
Global Biogeochemical Cycles
Introduction
The first auxiliary figure (“fs01.pdf”) shows the fit of the multi-linear regression used to estimate
preformed TA using surface data (<100 m) from the 2003 A16N and 2005 A16S sections.
The second auxiliary figure (“fs02a.png” and “fs02b.png”) plots the total particulate Ca
concentrations from suspended particulate matter samples in the top 1000 m along CLIVAR
A16N (a) and the lithogenic fraction of the particulate Ca pool (b). Total particulate Ca
concentrations were determined by energy-dispersive X-ray fluorescence (ED-XRF) as described
in the paper. The lithogenic fraction of the particulate Ca was calculated by using measured
particulate aluminum (pAl) concentrations as a proxy for lithogenic inputs and the average
crustal Ca:Al ratio as reported by Wedepohl [1995]:
lithogenic particulate Ca = [pAl] * (Ca:Al)crustal
The third auxiliary figure (“fs03.eps”) plots alkalinity due to CaCO3 dissolution (TA*) calculated
using carbon parameter measurements from the 1993 WOCE Atlantic zonal transect A06
(http://cdiac.ornl.gov/oceans/woce_a06.html) using the formulation for TA* described in the text
and the formulation for TAº derived by Chung et al. [2003] using data from the
WOCE/JGOFS/OACES Atlantic survey (1993–1998).
The fourth auxiliary figure (“fs04.pdf”) shows examples of the TA* vs. CFC-age relationships
along individual isopycnals that were combined to estimate CaCO3 dissolution rates following
the TA* method of previous studies [Feely et al., 2002; Sabine et al., 2002; Chung et al., 2004].
fs01.pdf: Estimated total alkalinity plotted versus measured total alkalinity in μmol kg-1 for
surface water (< 100 m) from the 2003 A16N and 2005 A16S sections plotted with the 1:1 line.
fs02a.png: Distribution of total particulate Ca in nmol L-1 along A16N. The color-scale has been
focused on a range of 0 to >200 nmol L-1 to focus on the concentration range of open-ocean
samples; higher concentrations (> 1 μmol L-1) are found in coastal samples.
fs02b.png: Distribution of calculated lithogenic particulate Ca in nmol L-1 along A16N.
fs03.eps: TA* (μmol kg-1) calculated using carbon measurements along the 1993 WOCE
Atlantic zonal transect A06 along 8°N.
fs04.pdf: Excess alkalinity (TA*) plotted versus CFC-12 age for data collected along the σθ=26.9
potential density surface in the low-latitude (0–30 °N) region (left) and along the σθ=27.3
potential density surface in the northern latitudes (30–55 °N) of the transect (right).
References:
Chung, S.-N., K. Lee, R. A. Feely, C. L. Sabine, F. J. Millero, R. Wanninkhof, J. L. Bullister, R.
M. Key, and T.-H. Peng (2003), Calcium carbonate budget in the Atlantic Ocean based on water
column inorganic carbon chemistry, Global Biogeochem. Cycles, 17, 1093, doi:
10.1029/2002GB002001.
Feely, R. A., C. L. Sabine, K. Lee, F. J. Millero, M. F. Lamb, D. Greeley, J. L. Bullister, R. M.
Key, T.-H. Peng, A. Kozyr, T. Ono, and C. S. Wong (2002), In situ calcium carbonate
dissolution in the Pacific Ocean, Global Biogeochem. Cycles, 16, 1144, doi:
10.1029/2002GB001866.
Sabine, C. L., R. M. Key, R. A. Feely, and D. Greeley (2002), Inorganic carbon in the Indian
Ocean: Distribution and dissolution processes, Global Biogeochem. Cycles, 16, 1067,
doi:10.1029/2002GB001869.
Wedepohl, K. H. (1995), The composition of the continental crust, Geochim. Cosmochim. Acta,
59, 1217–1232.