December 2011, the mercury lab returns to sweet steady land after spending a combined 55 days at sea and analyzing 3,188 samples between two legs of the North Atlantic Zonal Transect. I traded in 2AM stations calls, mandatory boat fire drills, and 24-hour lab days for my tiny apartment in Dayton, Ohio and returned to a graduate school lifestyle of course work, Chinese food and lengthy EPA reports.
I have spent the last two years pouring over the North Atlantic dataset, assessing the quality of each sample and piecing together patterns and relationships. To date, this is the largest dataset of mercury in the ocean and there is a lot to learn.
Part of the process is presenting my work at international conferences which gives me a push to dive deeper into the data and also opens the floor to criticism and advice from other experts in oceanography and mercury chemistry. I’ve traveled to Puerto Rico, New Orleans, and Salt Lake City to present at Aquatic Sciences and Ocean Sciences meetings, as well as the 10th International Conference on Mercury as a Global Pollutant in Halifax, Nova Scotia. Today, two years and half a dozen presentations later, I am still discovering new things in the data and have begun work on a paper that will be submitted to the journal Deep Sea Research II. The journal features “topical” studies in oceanography and there will be a special issue on the U.S. GEOTRACES North Atlantic Zonal Transect.
As work on the North Atlantic dwindles down to the publication phase, the next cruise is staged and ready to go! On October 25, I will embark on a 59 day cruise from Ecuador to Tahiti to study mercury in the Eastern Tropical Pacific Ocean. 3000 samples not enough you say? Well, the Pacific transect will offer a whole new story.
The Pacific Ocean is the deepest ocean in the world and holds the oldest water masses. The cruise will pass through waters along the coast of South America that are nutrient rich, promoting the growth of excess biomass (algae, phytoplankton). As this biomass dies and sinks, microbes in the water column act as garbage disposals of the ocean, breaking down and feeding on sinking organic matter. This type of microbial metabolism requires a lot of oxygen, depleting waters to near zero concentrations. There are few places in the world’s oceans where oxygen concentrations approach zero and this phenomenon is expected to have a notable effect on mercury chemistry.
Fellow mercury researcher Tristan Kading and myself in Halifax, Nova Scotia July 2011 at the 10th International Meeting on Mercury as a Global Pollutant.
Mississippi river from New Orleans, LA February 2013 at the ALSO Aquatic Sciences Meeting.
While the Pacific cruise is five months away preparations are in full swing. In the lab we’re busy making and ordering supplies, cleaning bottles and organizing the shipment of our gear…and ourselves. Please stay tuned, hginthesea with be active from October 2013 to January 2014 and you don’t want to miss it!