Deutsches Ozeanographisches Datenzentrum

Ziel der Reise / Objectives of Cruise:

The objective of the m²16 cruise is to repeat the zonal Med-SHIP01 line, 8 years after its last repeat (2018), and 15 years after its first implementation in 2011. This will add crucial knowledge on the different scales and magnitudes of variability and trends in circulation, hydrography, biogeochemistry and biology of the Mediterranean Sea. This will be done through conducting high quality measurements. The cruise has several interconnected scientific objectives focused on 1) understanding and documenting the changing hydrography of the Mediterranean Sea through studying properties and distributions of water masses, their changes, and the factors driving these changes, such as changes in stratification, and alterations in circulation and ventilation processes due to global warming, 2) quantifying current and future changes of the Mediterranean Sea biogeochemistry, focusing on the modifications in nutrients, oxygen, total alkalinity, dissolved inorganic carbon, the anthropogenic CO2, and the acidification levels, 3) understand and document changes in ventilation. In addition, this cruise will adopt the new addition to GO-SHIP, Bio-GO-SHIP, that includes novel sampling and sensors to in-vestigate the distribution of several biolog-ical variables. These scientific objectives address multiple scientific questions: 1) How is the hydrographic situation in the Mediterranean Sea's Eastern and Western basins developing? 2) How are eddies distributed in the EMed and WMed in 2025? Do they differ in the sub-basins? To what extent is heat and salt transferred into the vertical by eddies in the WMed and EMed during the cruise? 3) Is there are decrease in the ventilation rate of deep layers, due to a reduction of dense-water formation events? 4) What are the new trends of the carbonate system and storage of anthropogenic CO2 in the Mediterranean Sea? 5) What are the rates of uptake of the anthropogenic carbon and acidification in the Mediterranean Sea? Are these changing over time? 6) What is the magnitude of variability and trends in the inventory of oxygen and nutrients? 7) What are the base-line values of rarely measured Essential Ocean Variables (EOVs) such as DOC? Therefore, the primary goals of the cruise can be summarized as follows: 1) Obtain comprehensive data to establish a nearly synoptic view of property distributions throughout the entire Mediterranean Sea, encompassing all major sub-basins. 2) Utilize the collected physical and chemical data to analyze changes in circulation and ventilation patterns, as well as to assess variations in the inventory and distribution of properties, with a specific focus on inorganic carbon and the uptake of anthropo-genic carbon. 3) Address knowledge gaps in the understanding of the carbonate system in the Mediterranean Sea, including its sub-basins. This involves generating more accurate estimates of anthropogenic carbon and quantifying the rate of carbon storage and acidification levels. 4) Incorporate the measurement of new EOVs that are not routinely observed in the Medi-terranean Sea, bringing new insights. 5) Provide a first basin-wide estimate of bio-logical observations according to Bio-GO-SHIP.

Messungen / Measurements