Monday, July 22, 2013

Ella-Week 4-Adventures at Sea

This week, Katlyn and I got the opportunity to go out to sea on the infamous aluminium research vessel, The Elakha. Known for its roller coaster like ride, this boat has the well earned nickname of The Vomit Comet. The trip was funded by Pisco, a marine research program that focuses on investigating the physical and chemical properties of the intertidal and how they affect marine ecology. The particular lab group that we went out with is headed by Francis Chan, an assistant professor at OSU’s Zoology Department. Chan's lab group specifically focuses on the effects of ocean acidification and hypoxia. As our historic data set has been used to study hypoxic events, this was an excellent opportunity to not only get some sea time, but also to get some background on our project.

The stern of the Elakha as we leave
 Yaquina bay in the misty morning

We headed down south to a place called Strawberry hill, near Cape Perpetua, where the group has stationed some moorings that are checked up on a monthly basis. The objective of this trip was to get readings on the various instruments attached to the moorings that record abiotic factors such as dissolved oxygen and carbon levels. These two factors are then used in studying hypoxia and ocean acidification, respectively.

Helping to deploy a mooring (I'm on the left). 

Pictured below is one of the plots from an instrument at 13 meters of depth offshore of Strawberry hill. This plot reflects some of the recent upwelling off the Oregon coast. Upwelling happens when northerly winds push nearshore surface waters offshore, allowing deep, cold water to replace that water in the nearshore. This colder water from the deep has low oxygen and high saline concentrations, therefore, an upwelling signature can be seen on this chart as low temperature and oxygen levels, with an increase of salinity. Upwelling is occasionally balanced out with southerly winds, which cause a “downwelling” event ( an increase in temp and oxygen, decrease in salinity). You can see from this chart that the downwelling caused oxygen levels to get as low as .6 ml/l (that is milliliters of oxygen per liter of water).   This is relatively low as “severe hypoxia” is considered to be 0.5 ml/l .

Oxygen, Temperature and Salinity over days, near Cape Perpetua, Oregon
Here is a link to a much more detailed explanation of upwelling, complete with diagrams.

The crew and us on our return trip back to Yaquina bay,
enjoying the sun and comfy bean bags up on the observation
 deck (I finally succumbed to the power of the Dramamine). 
In preparation for departure, I took a “less sleepy” Dramamine, which never the less, pretty much knocked me out for most of the morning on board. Despite being desperately sleepy and still a little seasick, I was still able to chat about the mission with Tully Roher, who was acting as the chief scientist in Chan’s stead for the day. I was also able to help out a little with some simple tasks. The group would bring up the moorings using winches aboard the Elakha, gather the data from the instruments, clean off the algal growth with a pressure washer and then deploy the moorings again. At each station that we stopped at, a water sample would be taking by dropping a “niskin bottle”, an empty water container which is open at both ends, down a line. Once the bottle reached a desired depth, we would send a “messenger” down, which is a simple metal clip that would drop down the line, land on top of the niskin bottle and close it off, ensuring that the sample reflected the water at this depth. Dropping the messenger was my major contribution to the work done aboard the Elakha on that day, but I am still very grateful to have been able to be a part of the crew and experience science aboard a research vessel.

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