EarthRef.org Reference Database (ERR)
Development and Maintenance by the EarthRef.org Database Team

Detailed Reference Information
Johnson et al. 2003
Johnson, K.S., Elrod, V.A., Fitzwater, S.E., Plant, J.N., Chavez, F.P., Tanner, S.J., Gordon, R.M., Westphal, D.L., Perry, K.D., Wu, J. and Karl, D.M. (2003). Surface ocean-lower atmosphere interactions in the Northeast Pacific Ocean Gyre: Aerosols, iron, and the ecosystem response. Global Biogeochemical Cycles 17: doi: 10.1029/2002GB002004. issn: 0886-6236.

Here we report measurements of iron and aluminum in surface and subsurface waters during late March and late May of 2001 on transects between central California and Hawaii. A large cloud of Asian dust was detected during April 2001, and there was a clear signal in surface water iron due to aerosol deposition on the May transect. Iron and aluminum concentrations increased synchronously by 0.5 and 2 nM along the southern portion of the transect, which includes the Hawaii Ocean Time series (HOT) station, from background values in March (0.1 to 0.2 nM Fe). These changes occurred in a ratio that is close to the crustal abundance ratio of the metals, which indicates a soil aerosol source. A vertical profile of dissolved iron was also measured at the HOT station in late April and this profile also shows a large increase near the surface. Direct observations of aerosol iron concentration at Mauna Loa Observatory on Hawaii indicate that aerosol concentrations were significantly lower than climatological values during this period. Soil aerosol concentrations along the transect were estimated using the real-time Navy Aerosol Analysis and Prediction System (NAAPS). The NAAPS results show a large meridional gradient with maximum concentrations in the boundary layer north of 30¿N. However, the deposition of iron and aluminum to surface waters was highest south of 25¿N, near Hawaii. There were only weak signals in the ecosystem response to the aerosol deposition.

BACKGROUND DATA FILES

Abstract

Keywords
Oceanography, Biological and Chemical, Aerosols, Oceanography, Biological and Chemical, Biogeochemical cycles, Oceanography, Biological and Chemical, Nutrients and nutrient cycling, Oceanography, Biological and Chemical, Trace elements
Journal
Global Biogeochemical Cycles
http://www.agu.org/journals/gb/
Publisher
American Geophysical Union
2000 Florida Avenue N.W.
Washington, D.C. 20009-1277
USA
1-202-462-6900
1-202-328-0566
service@agu.org
Click to clear formClick to return to previous pageClick to submit