The Healy holds a lot of science pioneers onboard. One group of pioneers is Rob Rember and Ana Aguilar-Islas. Rob is a Research Technician and Ana is a Post-Doctoral Fellow with Jingfeng Wu from the International Arctic Research Center at the University of Alaska-Fairbanks. Rob and Ana are sampling for the first time ever the iron amounts in the ice and the water under the ice here in the Bering Sea.
Iron in some locations can be a limiting factor to the productivity of an area. This is very true of areas that have high nutrients but low chlorophyll levels such as the Gulf of Alaska. The lack of these trace elements, such as iron, is found to actually be the reason for these conditions.
Ana Carrying
Ana carrying the sampling device for iron back into the science lab.
To test for iron in the water, Rob has adapted a device once used at moorings to now be used to collect water samples with trace metal clean bottles. This sampling device looks much like a large, plastic weather vane but contains a circuit board that is used to operate the device remotely. The collecting bottles are filled with distilled water and closed prior to use.
Circuit Board
The control center of the sampling device where all commands are sent.
Once all the commands are programmed, Rob and Ana place about 5 sampling units onto the same cable the CTD is attached to which is used as a very expensive weight. After 25 minutes all bottles open and the distilled water is replaced with seawater at the depth the unit is at because of basic density rules. The bottles remain open for a set amount of time and then are closed.
Rob and Ana
Rob and Ana work together to get their iron samples from the water at a station.
The collecting of the water is just one step of the process. Now all the biological matter in the water collected must be removed. This is done in an area that is free of all atmospheric influences that Rob worked on at the beginning of the cruise to set-up.
Rob Setup
Rob works to put up a safe area that the water samples can be filtered.
Why filter the water? The water collected in their bottles will also collect many microscopic organisms. They must filter them out so that the iron found is only the amounts dissolved in the water. Rob and Ana are not doing anything more than collecting on this cruise. They will find the actual amounts of iron once they get back to Fairbanks, AK.
Ana Filter
Ana smiles as she labels yet another bottle of water that has been filtered.