26 | Cruise Report, RV ATAIR, Cruise 0671021-1, Bremerhaven - Thyboron —- Aberdeen, 18 Jul - 10 Aug 2023

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RV Atair
Cruise 0671021-1
18 Jul - 10 Aug 2023
Sremerhaven-Thyboron-Aberdeen

51° A 1
8°W 6°

4°

Bf

no

zn

mc

Ro

Ro

40° 12°E

Figure 5.8. Distribution of stations carried out during cruise 0671021-1 with water sampling and subsequent
 filtration for chlorophyll-a determination (red dots).

The chlorophyll-a concentrations measured in the laboratory serve 1) as a rough measure of
ohytoplankton biomass and 2) are used for comparison with the chlorophyll-a concentrations
determined by remote sensing (ground truthing).

Phytoplankton Sampling

Understanding the distribution and behaviour of plankton is key to deciphering the complex
dynamics of marine ecosystems. The assimilation of satellite data bridges the gap between
observation and theory. The EnsAD project aims to improve real-time forecasting capabilities
for potentially problematic phytoplankton groups by integrating hyperspectral remote sensing
data from the ENMAP and PACE satellites into biogeochemical models for the North Sea and
Baltic Sea. In order to adapt the algorithms, the composition of the phytoplankton must be