Measuring dissolved oxygen at GEOF337 student cruise

In order to measure the oxygen levels, we lower down an instrument called CTD (as seen in the picture).

A CTD instrument on deck of Kristine Bonnevie, waiting to be deployed into the sea

The CTD measures conductivity (salinity), temperature and depth (pressure). It has grey plastic bottles attached to it, with which we can take water samples at different depths and analyze for oxygen content in the lab.

By adding chemicals to the water samples, we bind the oxygen so that we later can calculate the concentration through the titration technique.

Titrating an oxygen sample to measure the oxygen concentration

This blogpost is one of a series written originally for our Insta-takeover of @PortalenIGLO, by the awesome night watch team Elina, Helene, Julie, and Sonja. Check out the twitter accounts of Elina and Sonja for updates on what they are doing when they are not at sea with us!

Why we chose to go to Masfjorden for the GEOF337 student cruise

Masfjorden is 24km long, branching out from Fensfjorden. Masfjorden has three sills (a sill is an underwater barrier), which prevent the undisturbed water flow in and out of the fjord. This is why the oxygen levels near the sea floor are particularly low, limiting the marine life as well as decomposition processes. To get new oxygenated water into the basins, dense Atlantic water needs to flow over the sill – this does not happen very often! This week we will study the Masfjorden water masses through a series of measurements.

Map of the bathymetry of Masfjorden and Fensfjorden. The deepest parts are yellow, the shallowest parts are blue.

This blogpost is one of a series written originally for our Insta-takeover of @PortalenIGLO, by the awesome night watch team Elina, Helene, Julie, and Sonja. Check out the twitter accounts of Elina and Sonja for updates on what they are doing when they are not at sea with us!

GEOF337 Student cruise to Masfjorden

This blogpost is one of a series written originally for our Insta-takeover of @PortalenIGLO, by the awesome night watch team Elina, Helene, Julie, and Sonja. Check out the twitter accounts of Elina and Sonja for updates on what they are doing when they are not at sea with us!

Ahoy from Masfjorden!

This week we are a group of UiB students going on a cruise, and we are taking over the #portalenIGLO. The ship is called Kristine Bonnevie and is one of IMR’s research vessels. Our study area is mainly Masfjorden, but we are also taking some samples from Fensfjorden, both a five hour journey north of Bergen. This week we will show you what we typically are doing on a fjord-oceanography cruise.

The Masfjorden 2019 crew