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Floating chamber used to collect gases emitted from the ocean (Photo by Craig Stevens).

Our laboratory setup for measuring CO in seawater (Photo by Lori Ziolkowski).

Albatross tries to taste the line to which the SCAMP profiler is attached (Photo by Brian Ward).

Close to midnight last night the injection of iron and tracer gases was complete. Overnight mapping confirmed the creation of a patch. Measured iron concentrations in the patch were, as expected, up to 3 nM. This morning brought the beginning of our routine sampling schedule with two CTDs. The gas cast, which is always a circus, led the two casts this morning. On each of these CTD casts, we collect water for our respective experiments. Some of the gas people are looking at tracer gases injected into the patch, while others are looking at naturally occurring gases, such as nitrous oxide, carbon monoxide or dissolved oxygen.

Peter Morrison, our intrepid RHIB driver at the controls of the small workboat during an afternoon deployment (Photo by Brian Ward).

Today in the relatively calm conditions, the Rigid Hull Inflatable Boat (RHIB) was deployed for the first time. Craig Stevens and Brian Ward had an opportunity to test the various near surface profilers i.e. SkinDeEP, SCAMP, and TRAMP.

Photochemistry Group

During this experiment, with the assistance of Cliff Law, I will be examining the production of one of the dissolved gases, carbon monoxide, as it is produced by the action of sunlight. CDOM or Coloured Dissolved Organic Matter, is naturally occurring carbon dissolved in the water. When it absorbs sunlight in the water column, it breaks down and one of its products is carbon monoxide. Carbon monoxide produced in the water column eventually leaks out into the atmosphere where it plays an important role in atmospheric chemistry.

Contributor Lori Ziolkowski

My goal on this voyage is to measure the efficiency of the carbon monoxide production, otherwise known as the Apparent Quantum Yield (AQY) for CO. This measurement has been made in a few other locations in the world’s oceans and today it is unclear if this value changes from location to location. I would like to get a better estimate of CO AQY in this region of the world’s oceans. Members of the photochemistry group are Lori Ziolkowski (Dalhousie University) and Cliff Law (NIWA).

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