19 May 2019
It’s been another grey day on the North Sea, though luckily everyone’s as happy as a kid in a candy shop. Well, if the kid was a highly trained scientist and the candy was fresh samples for analyses…
We’ve been collecting 3 different types of samples during this cruise: sediment, water and gas. Together they are giving us a full picture of exactly how the release of CO2 is affecting the area.
The gas samples are collected by the ROV, catching escaping bubbles in a reverse funnel before sucking them into a vacuum sealed bottle. These are then analysed back on board by Anita who’s looking for exactly how the gas content has changed from what we initially injected.
The sediment samples are collected using push cores. These empty cylinders are slowly pressed about 30cm into the sediment by the ROV before being pulled up, with all the mud and sand from the seabed wedged inside. Once on board Doug and Kate work to dissect the samples so we can later examine how the chemical properties vary with depth.
Water samples are being collected in a whole manner of different ways. The easiest to understand is probably the benthic chamber lander, which sits on the seabed and sucks in water samples using on-board syringes. Once back on the surface, Jonas sets to work prepping them for later analyses.
Perhaps the most impressive water sampling system we have though belongs to the sensors team of Allison, Sam and Rudi. Their “Lab on Chip” system allows them to collect water samples and analyse them all under the sea. With sensors attached to the baseline lander, the benthic boundary lander and also the ROV, they are able to measure levels of phosphate, nitrate, total alkalinity, pH and dissolved inorganic carbon without even lifting a finger. You’d think that free up a lot of their time but sadly the sheer number of sensors require a lot of maintenance.