Publication Date:
2020-02-12
Description:
The need to cover established and emerging Essential Ocean Variables (EOVs) as defined by the
Global Ocean Observing System (GOOS) calls for the development and refinement of the available
sensors and samplers, specifically for biogeochemical and biology/ecosystem observations. For
several of these EOVs as well as for microplastics as a relatively novel variable of particular societal
concern, technological progress has been made as part of AtlantOS. This involves the samplers and
sensors and the platforms to use them from as such as well as the required methodologies for
obtaining relevant and well-validated results and disseminate data according to the FAIR principles.
For biological observations, a main focus was on automated sampling of particles and water
samples. While active, pump-based samplers for particles in the water column have been available
for many years, it turned out that they were not yet fully mature for operational sampling of
zooplankton, microorganisms (e.g., bacteria, archaea, phytoplankton and other eukaryotic
unicellular organisms), and microplastics. AtlantOS partners joined forces with manufacturers to
overcome limitations with respect to quantitative filtering without leakage, avoidance of plastic
contamination and the option for preservation with appropriate agents. Technical solutions were
identified and partly tested but could not in all cases be fully implemented in the time frame of the
project. Technologies for automated water sampling proved to be more mature and samplers could
already be successfully included in observation programs. For both water and particle samples only
very few manufacturers offer off-the-shelf solutions which slows down innovation and adaption to
user’s needs and may impede successful implementation of appropriate instruments on a larger
scale.
Particle traps are well-established and operational passive samplers of sinking particles that are
widely used for phytoplankton and particulate matter observations based on microscopic sorting
and chemical analyses. Using legacy samples collected in the Arctic it could be demonstrated that
the same samples can also be used for omics-based observations allowing to address the emerging
EOV ‘Microbe biomass and diversity’ and also contributing to the ‘Phytoplankton biomass and
diversity’ EOV. Applied to legacy samples also from other sites, this holds the potential to assess
past microbial communities of the Atlantic that could serve as a baseline for comparisons to recent
communities that are subject to global change.
Significant progress was achieved in building capacities for the implementation of omics-based
observations of marine organisms into recent and future observation programs. The feasibility of
samplers and different preservation agents was tested and a comparison of different methods for
omics-based investigations of microbial communities was conducted. The Global Omics Observatory
Network (GLOMICON) was established to better connect the institutes and initiatives that are active
in the field. As part of GLOMICON, solutions were implemented that allow for a registration of omics
observatories and for the sharing of protocols and bioinformatics code. Irrespective of these
achievements, major steps still need to be taken to consolidate and standardize approaches in this
rapidly evolving field and to establish operational and well-integrated omics-observations as part of
an Atlantic Ocean Observation System.
For biogeochemical observations, the focus was placed on sensors for oxygen and marine CO2
system parameters (pCO2, total alkalinity) and their readiness for integration into classical as well as
emerging biogeochemical observation platforms.
For oxygen, the situation is very favourable as the oxygen optode technology and the best practices
routines developed around it can be considered fully operational. There are no obstacles for the
D3.17 „OceanSITES Innovation Report“
5
integration of oxygen optodes into the full range of autonomous ocean observation platforms
(mooring, drifter, glider, wave gliders, floats, voluntary observing ship etc.).
For marine CO2 system parameters, work carried out in AtlantOS focussed the CO2 partial pressure
(pCO2) and total alkalinity (TA). With respect to pCO2 it can be stated, that the membraneequilibration sensors with NDIR detection have clearly matured to a level that they can be used
routinely on a range of platforms (mooring, wave glider, voluntary observing ship) with an accuracy
of ~1% under well-constrained operation conditions and with rigorous data processing routines.
Major limitations still exist, however, for this sensor technology on moving platforms (long sensor
response time) and platforms with stringent payload and energy limitations (float, glider etc.). In
contrast, the pCO2 (as well as pH) optode technology, in which significant hopes lie, has not been
forthcoming and existing products still do not meet the quality requirements for open ocean
applications. For TA, our intensive testing both in the laboratory and in the field has led to significant
improvement of the commercially available system, which now can be considered operational. It
allows high-quality autonomous bench-top measurements (e.g., on voluntary observing ships).
Ideas for a submersible version of the system are in early stages and would need significant design
and testing efforts.
With respect to the possibilities of oxygen and carbon measurements from novel autonomous
observation platforms, our work in AltantOS has shown very promising applications on profiling
Argo floats, submersible winch systems with upper ocean profilers as well as wave gliders. On all
these platforms, we were able to successfully implement oxygen and carbon measurements for
high-quality observations.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Miscellaneous
,
notRev
Format:
application/pdf
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