Monday, August 20, 2012

13 Aug 2012 - Back on Land...

[Ed: We'll have a few follow-up posts about the cruise now that we're back on land.]

Lots of Data!

Well the cruise is over, the equipment is packed, and the data binder is tucked safely in my backpack! We just have a couple more days in Oregon and then it's back to Long Island! I am happy to report that we titrated 1,524 organisms on this cruise! This means I have a lot of data analysis to do when I get home! I wanted to explain how we use our titration data to calculate an organism's density since it was never fully explained earlier. When titrating, we record the amount of seawater and glycerin mix that was added to make the organisms become neutrally buoyant, as well as the temperature and salinity of the seawater. We use the temperature and salinity to calculate the density of seawater. The density of the glycerin mix is calculated from the density of glycerin and the density of seawater. We then use these values in the following equation to calculate the animal's density.

Animal Density = ( (Seawater Density * Seawater Volume) + (Mix Density * Mix Volume))/(Seawater Volume + Mix Volume)

We can then use the animal's density in a model that helps us understand how these animals scatter sound. This information can allow us to use acoustic data to make estimates about how many animals are in the water column.

It was such a great cruise and I have enjoyed being a tourist and getting to see some of Oregon before our trek back to Long Island. With over 1500 organisms measured, I'm predicting a very busy semester filled with data analysis!!

Until our next cruise.


The ALES team on the bow of the Oceanus! Photo credit: Kelly Benoit-Bird

Steph and I busy at collecting data! We each titrated over 600 organisms!! Photo credit: Dezhang Chu.

We spotted some California sea lions in Newport when we went to lunch after we got off of the boat!!