iodysséus (https://www.iodysseus.org) is an offshore sailing ship equiped as an oceanographic platform.

Data have been collected  during 3 legs (around 3500 nautical miles in total) during the spring 2019. The navigation zones are on biological phenomena, corresponding to the zones where the CO2 varies widely, thus measurements taken provide extra information to help restrict seasonal variability and the seasonal CO2 cycle (and help to calculate the rate of ocean acidification).

(During the spring, the partial pressure of CO2 decreases during bloom phenomenon because planktonic microorganisms pump CO2 for their growth).

The physico-chemical parameters of the surface water have been continuously measured thanks to an Ocean Pack : temperature, salinity, dissolved oxygen, chlorophyll-a concentration, and partial CO2 pressure (pCO2).

(This device was developed and adapted for racing yachts. Both compact and light, it consumes very little energy. One of its many advantages is that it can still operate at speeds above 15 knots. It shows that modern oceanography is evolving towards more flexible models).

leg 1: from 19-04-21 to 19-04-24

leg 2: from 19-05-13 to 19-05-21

leg 3: from 30-05 to mid june

Three maps below: partiel pressure of CO2 (ppm)