Dear readers,

Forced by the meteorological conditions that we have faced in the last days, we have to stop the experiment. On March 6th, the wind blew at more than 110 km/h, creating lots of waves in the bay. We have continued the experiment for few more days, but we realized something went wrong when looking at the CTD profiles. Although our mesocosms are well covered with a Teflon roof in order to prevent rain to enter inside the bags, we saw that salinity dropped significantly at surface in all mesocosms after March 7th. Divers from LOV inspected the bags and our fear was justified. All of the bags with no exceptions presented many scratches in the first meters. We have considered (and actually tried) lifting up the bags in order to put these scratches above the sea level, but we had to give up as for some of them the bag was deteriorated way too deep below the sea surface. That is very unfortunate, Villefranche bay is a safe sheltered place for more than 350 days a year, our experiment coincided with very windy conditions from the East, allowing waves and swells to enter inside the bay. All is not dark of course, this could have happened at the start of the experiment and all in all I think we have been lucky collecting more than 2 weeks of data.

Now it’s time for us to start removing the mesocosms from the bay, our partners will move back to their home countries in the coming days and will start analysing the precious samples. We’ll come back for more news at a later stage!

Keep posted
F

Example of salinity profiles acquired since the start of the experiment and showing the continuous intrusion of external waters in the bags after the storm of March 6th.

Example of salinity profiles acquired since the start of the experiment and showing the continuous intrusion of external waters in the bags after the storm of March 6th.