Dataset:Thorium-234 and Uranium-238 from R/V Melville, USCGC Polar Star cruises COOK19MV, PS02_2002 from the Southern Ocean, south of New Zealand in 2002 (SOFeX project)
Project(s):Southern Ocean Iron Experiment (SOFeX)
Description:Thorium-234 and Uranium-238

Thorium-234 and Uranium-238 from the 2002 SOFeX project South Patch experiment

 dates:           30 January 2002 to 20 February 2002  (20020130-20020220) 
 location:        N: -65.57  S: -66.59  W: -172.93  E: -170.79 
 project/cruise:  SOFeX/MV and SOFeX/PS
 platform:        SOFeX multi-ship: R/V Melville and USCGC Polar Star
 
 
 Methodology: Buesseler, et al. 2005

    "Particle export during the Southern Ocean Iron Experiment (SOFeX)". Limnol. 
    Oceanogr., 50(1). American Society of Limnology and Oceanography, Inc. pp.311-327. 
 
 Change history: YYMMDD 
    070323: data contributed by Ken Buesseler as emailed PDF file
    070418: added to OCB database by Cyndy Chandler, OCB DMO, (cchandler@whoi.edu) 
    070504: changed BC_01 time and TM033 and TM043 dates to match event log; 
            event, station, ev_type, and date match corresponding cruise event logs
Acquisition Description:

Thorium-234 and Uranium-238 from the 2002 SOFeX project South Patch experiment


 Methodology: Buesseler, et al. 2005

    "Particle export during the Southern Ocean Iron Experiment (SOFeX)". Limnol. 
    Oceanogr., 50(1). American Society of Limnology and Oceanography, Inc. pp.311-327. 
 
Processing Description:
 Change history: YYMMDD 
    070323: data contributed by Ken Buesseler as emailed PDF file
    070418: added to OCB database by Cyndy Chandler, OCB DMO, (cchandler@whoi.edu) 
    070504: changed BC_01 time and TM033 and TM043 dates to match event log; 
            event, station, ev_type, and date match corresponding cruise event logs

Project Information

Southern Ocean Iron Experiment

Before he passed away in 1993, John Martin suggested that an increase in the flow of iron-rich dust to the ocean causes phytoplankton (single celled algae) to grow. The increased photosynthesis removes carbon dioxide from surface waters as the algae create biomass. This carbon dioxide is replaced by carbon dioxide gas that flows into the sea from the atmosphere. Reduced carbon dioxide in the atmosphere cools the planet (CO2 is a greenhouse gas that warms the earth). The results of this work, funded by the National Science Foundation, the Department of Energy, and the US Coast Guard, will be a much better understanding of how biological processes may regulate climate. (see Related Info: Fe cycle) A direct test of the 'Martin Hypothesis' that trace concentrations of Fe are responsible for phytoplankton's ability to grow by direct experimental addition of Fe to the surface waters. Consequently the distribution of bioavailable Fe in the surface waters determines large geographical areas primary production and the following flux of fixed organic matter to the deep sea. The aim of the SOFeX project is to investigate the effects of iron fertilization on the productivity of the Southern Ocean. The results of this work will contribute significantly to our understanding of important biogeochemical processes which bear directly on the global carbon cycle, atmospheric carbon dioxide concentration, and climate control. The SOFeX-N and SOFeX-S designations are sometimes used to distinguish between two iron enriched patches - one in low silicate waters north of the polar front (SOFEX-N), and the other in high silicate waters south of the polar front (SOFEX-S). All three ships, Melville (MV), Revelle (RR) and Polar Star (PS), worked in SOFEX-S, but only the Revelle and Melville worked in the SOFeX N patch and shuttled between the two patches.



Deployment Information

Deployment description for R/V Melville COOK19MV

Brief cruise plan description: Three ships were involved in the SOFeX experiment. Each ship operated in the study area at a different time to afford the longest observation time. The designations SOFeX-N and SOFeX-S are sometimes used to distinguish between two iron enriched patches - one in low silicate waters north of the polar front (SOFEX-N), and the other in high silicate waters south of the polar front (SOFEX-S). All three ships, Melville (MV), Revelle (RR) and Polar Star (PS), worked in SOFEX-S, but only the Revelle and Melville worked in the SOFeX N patch and shuttled between the two patches. The R/V MELVILLE sailed several weeks after the R/V REVELLE to arrive in the study area just as the 'patches' were forming in response to iron fertilization. The MELVILLE's team planned to make detailed measurements of phytoplankton physiology and rate processes, and to sample daily for phytoplankton growth rates and biomass, soluble and particulate iron and zooplankton biomass. A cruise logbook includes daily entries filed by the Chief Scientist aboard each vessel.

Dataset Acquisition Description: Thorium-234 and Uranium-238 from the 2002 SOFeX project South Patch experiment Methodology: Buesseler, et al. 2005 "Particle export during the Southern Ocean Iron Experiment (SOFeX)". Limnol. Oceanogr., 50(1). American Society of Limnology and Oceanography, Inc. pp.311-327.

Dataset Processing Description: Change history: YYMMDD 070323: data contributed by Ken Buesseler as emailed http://ocb.whoi.edu/SOFeX/PI-NOTES/data_orig/0311a1.pdf">PDF file 070418: added to OCB database by Cyndy Chandler, OCB DMO, (cchandler@whoi.edu) 070504: changed BC_01 time and TM033 and TM043 dates to match event log; event, station, ev_type, and date match corresponding cruise event logs



Deployment description for USCGC Polar Star PS02_2002

Cruise dates provided by David Forcucci, USCG Science Liaison Brief cruise plan description: Three ships were involved in the SOFeX experiment. Each ship operated in the study area at a different time to afford the longest observation time. The designations SOFeX-N and SOFeX-S are sometimes used to distinguish between two iron enriched patches - one in low silicate waters north of the polar front (SOFEX-N), and the other in high silicate waters south of the polar front (SOFEX-S). All three ships, Melville (MV), Revelle (RR) and Polar Star (PS), worked in SOFEX-S, but only the Revelle and Melville worked in the SOFeX N patch and shuttled between the two patches. The USCGC Polar Star was the third of the three vessels to occupy the SOFeX study area in 2002. The main focus of the scientific party aboard the Polar Star was to assess how much carbon was removed from the iron fertilized patches. The cruise report includes a more complete description of the Polar Star cruise and a cruise logbook includes daily entries filed by the Chief Scientist aboard each vessel.

Dataset Acquisition Description: Thorium-234 and Uranium-238 from the 2002 SOFeX project South Patch experiment Methodology: Buesseler, et al. 2005 "Particle export during the Southern Ocean Iron Experiment (SOFeX)". Limnol. Oceanogr., 50(1). American Society of Limnology and Oceanography, Inc. pp.311-327.

Dataset Processing Description: Change history: YYMMDD 070323: data contributed by Ken Buesseler as emailed http://ocb.whoi.edu/SOFeX/PI-NOTES/data_orig/0311a1.pdf">PDF file 070418: added to OCB database by Cyndy Chandler, OCB DMO, (cchandler@whoi.edu) 070504: changed BC_01 time and TM033 and TM043 dates to match event log; event, station, ev_type, and date match corresponding cruise event logs