dissolved aluminium distribution along 40ºs d357 & jc068
DESCRIPTION
Dissolved aluminium distribution along 40ºS D357 & JC068. Jessica Klar , Christian Schlosser, Maxi Castrillejo Iridoy , Eric Achterberg National Oceanography Centre of Southampton. Post-cruise meeting 10 th – 11 th September 2012. Aluminium geochemical cycle. - PowerPoint PPT PresentationTRANSCRIPT
Dissolved aluminium
distribution along 40ºS
D357 & JC068Post-cruise meeting 10th – 11th September 2012
Jessica Klar, Christian Schlosser, Maxi Castrillejo Iridoy, Eric AchterbergNational Oceanography Centre of Southampton
2
Ocean
Crust
Atmospheric dust transport
PO4, Fe
Al
CO2
Biological Carbon Pump
Aluminium geochemical cycle
• Free Al3+
• Al-hydroxide complexesAluminium speciation in aqueous samples
Aluminium is highly particle reactive
Methods• 0.2 µm filtered seawater samples• Flow Injection Analysis Lumogallion fluorescence
Resing, J A & Measures, C I 1994. Fluorometric determination of Al in seawater by Flow-Injection-Analysis with in-line preconcentration. Analytical Chemistry, 66, 4105-4111.
• Toyopearl AF-Chelate-650MBrown, M T & Bruland, K W 2008. An improved flow-injection analysis method for the determination of dissolved aluminum in seawater. Limnology and Oceanography-Methods, 6, 87-95.
• Quality controlo Internal standardso SAFe
LOD LOQ Typical precisionD357 0.23 nM 0.78 nM ~ 8 % at 2 nM dAl
~ 2 % for > 7 nM dAlJC068 0.21 nM 0.69 nM ~ 6 % at 2 nM dAl
~ 3 % for > 5 nM dAl
Internal Standard
0 5 10 15 20 25 30 35 400.0
0.5
1.0
1.5
2.0
2.5
3.0 Reference SW A
Reference SW B
Reference SW C
Al (
nM)
Ref A: 0.36 ± 0.17 nM dAl (46 %)Ref B: 0.37 ± 0.19 nM dAl (51 %)Ref C: 2.30 ± 0.27 nM dAl (12 %)
SAFE S 12
0 1 2 3 41.50
1.55
1.60
1.65
1.70
1.75
1.80
1.85
1.90
1_4h
1_19c
consensus
dAl (
nM)
1_4h: 1.83 ± 0.13 nM dAl 1_19c: 1.86 ± 0.18 nM dAl Consensus: 1.74 ± 0.09 nM dAl
JC068
-60 -50 -40 -30 -20 -10 0 10 20 300.00
2.00
4.00
6.00
8.00
10.00
12.00
0
5
10
15
20
25
30
35
40
dAlSili-catesalinity
dAl (
nM)
salin
ity
Courtesy of Christian Schlosser
dAl (nM)
9
D357
D357
JC068
JC068 + D357
AAIW
NADW
River Plata Al source
AADW
NADW
AABW
AAIW
GEOTRACESGD-23 18.7 ± 0.8 nM GS-57 28 ± 3 nM
14
D361
Summary
• Extremely low dust depositions• AAIW transports low dAl waters. Water formation
with low dust depositions• NADW shows higher dAl concentrations• Higher dAl concentrations approaching River
Plata• No higher dAl in the proximity of MAR or
sediments
Publication planning• D357 + JC068 dAl in ONE paper• Need aerosol data• Master student for Total dissolvable Al analysis• Publication deadline?