Depth profile water sampling

Yesterday (July14) Adina, Joe and I joined the NMP cruise to sample water from different depth at "A" point at Gulf of Aqaba.

This map shows where point A is. It's at the adjacent point of boards of Israel, Egypt and Jordan. Map is from Chase et al., 2011

Since we were on the big research vessel instead of small speed boat, I didn't get seasick at all. The marine team of IUI is excellent, they operate the research vessel very well and fulfill varies of requirements from different research. In order to get water samples from different depth, we need to deploy go-flow bottles on a rosette into the ocean. Those bottles were open when they went down to the water, the way we collect water is that we send a signal to close the lids while we lift it up, we can control lids for every single bottle when we want so we can collect water from different depth in different bottle.

Marine team is deploying go-flow bottles on a rosette

    After they lifted the rosette back to the deck, we can collect water samples from an outlet near the bottom of the bottles.

Researchers were collecting water from go-flow bottles

One part of my research target is to measure trace metal composition in particulate matter of seawater, so other than filtered seawater, we need to collect unfiltered seawater. After I was back to the lab, I filtered ~5L water to get particulate matter on polycarbonate filters, then I will do acid digestion then do following analyses.

I was setting up filtration system for particulate matter in seawater

 With trace metal composition in different component of the seawater and sources to seawater, we will be able to find out what control trace metal distribution in Gulf of Aqaba. Joe has a different target, he wants to use nitrogen isotopes to identify potential nutrient sources to the gulf and the mixing in the gulf, also the level of nitrogen fixation by biomass.