The continental margin as a source of iron to the open ocean
|Iron to the Eastern Tropical Atlantic: We'll be cruising across the Atlantic on the Oceanus in August 2008 from Barbados to Cape Verde, then to the coast of Mauritania and finally ending in the Canary Islands.|
|CoFeMUG on the Knorr! We'll be crossing the Atlantic in Nov-Dec 2007 from Brazil to Namibia, passing through the Benguela Upwelling System, one of the most productive marine ecosystems on Earth.|
Iron is the most important micronutrient in the ocean, limiting biological productivity in large regions of the world. Atmospheric dust deposition is commonly thought to be the primary mode of external iron supply to the open ocean. The projects I am working on are showing that the subsurface lateral transport of iron from the continental margins may be just as important as dust in delivery iron to the open ocean.
Relevant projects include (cruise participation listed in parentheses):
1) Sources of iron to the eastern tropical Atlantic: does the
continental margin supplement Saharan dust? (R/V Oceanus, August 2008)
2) Geochemistry of marine particulates in the oligotrophic South Atlantic and Benguela upwelling region ("CoFeMUG: Co, Fe, and Microorganisms in an Upwelling zone and Gyre" on the R/V Knorr, November-December 2007).
3) Iron control of productivity and export in the Subantarctic Zone (SAZ) ("SAZ-SENSE: SubAntarctic Zone SENSitivity Experiment" on the Aurora Australis, January-February 2007).
4) Lateral transport of iron in the HNLC Western and Eastern Subarctic Pacific. For a nice writeup on this, see http://www.lbl.gov/Science-Articles/Archive/sabl/2006/Mar/02-winter-iron.html