Hydrodynamics and Data Assimilation


One important part of our work is the cooperation with other research institutes, public institutions and companies. We have participated in multiple national and international projects. Some of the current projects are described below.

The CEASELESS project will demonstrate how the new Sentinel measurements can support the development of a coastal dimension in Copernicus by providing an unprecedented level of resolution / accuracy / continuity with respect to present products. The retrieval and validation for restricted domains and for an enlarged set of combined, user oriented variables will be the basis to advance the state of the art in assimilation, modelling and applications, at a level commensurate with the new Sentinel capabilities. The project will address the multiple scales coexisting in littoral areas by developing new shallow water parameterizations, introducing them into coupled model suites (wind-wave-surge-current-land discharge) and producing new standards for coastal simulations and analyses. The permanent data base, with dynamic repositories, plus the modular structure of the developed models will demonstrate the technical feasibility of a future operational Copernicus coastal service. The set of derived products will be ingested into the users’ work routines, proving the economic feasibility of the Copernicus coastal extension. The level of conflicts in squeezed coastal zones, expected to grow in the face of climate change, will, thus, benefit directly from CEASELESS, establishing tangible contributions for a wide range of economic sectors. The data repositories (accessible via a dedicated portal), regularly updated with the evolving (satellite-derived) bathymetry will facilitate the use/re-use of our high resolution results, supporting a new set of Copernicus coastal applications such as renewable energy, coastal erosion or harbor exploitation. The mutual validation of satellite data, numerical results and in-situ observations will generate reciprocal profit for enhanced competiveness of EU coastal industries where we shall also explore the suitability for cases in 3rd countries, opening new business opportunities for a coastal Copernicus.
HZG leads the work package entitled "Derived products / performances as proof-of-concept for a Copernicus coastal service".

Black Sea – Monitoring Forecasting Centre (BS MFC) provides regular and systematic information about the physical state of the ocean and marine ecosystems for the Black Sea. The system is based on a numerical ocean model assimilating in-situ and satellite data. BS MFC gathers expertise in the field of ocean analysis and forecast in the Black Sea, brings together knowledge of the regional Black Sea dynamics, and enhances technical links with other CMEMS components and strong connection with the MED MFC. Moreover, BS MFC’s objectives include the planning and efficient implementation of systems upgrades.
BS MFC is coordinated by the Institute of Oceanology, Bulgarian Academy of Sciences in collaboration with Fondazione Centro Euro-Mediterraneo sui Cambiamenti Climatici, Helmholtz-Zentrum Geesthacht, Institute for Coastal Research, Université de Liège, Sofia University “St. Kliment Ohridski”, Eurasian Institute of Earth Sciences. HZG is a Production Unit (PU) for BS- Waves, Backup Unit (BO) for BS-Physics and Joanna Staneva is a "Science Expert" in the project.

WAVE2NEMO contributes to the development of the COPERNICUS Marine Environment Monitoring Service (CMEMS). It specifically aims at improving the coupling of the ocean model system to wave models. The target areas are the North Sea, the Baltic Sea and the Mediterranean Sea. The main objectives of the project are:
• Further development of the NEMO ocean model and the forcing which will explicitly include the effect of waves from wave models on the upper ocean dynamics;
• Providing software for additional parameters which have to be exchanged between waves and hydrodynamic models,
• Improved validation methods by retrieved wave information from satellite data and in situ platforms (buoys, moorings, HF radars, etc.);
• Demonstrating the interaction of waves and currents at small scales both in the ocean interior as well as near the shoreline.
Most of the CMEMS target fields - marine safety, marine resources, marine environment and forecasting – will directly benefit from the proposed R&D work proposed here. Thus, it could be expected that the project will make connections to CMEMS in order to support the future production of more consistent ocean-marine weather information including on surface waves, which is often requested by users.

About the ESM project

The ESM project started on 1 April 2017 partly funded by the Helmholtz Association over a period of three years. The project comprises eight Helmholtz Research Centers and aims to improve the representation of the components of the Earth system and their coupling, as well as to perform a series of selected numerical experiments to address Grand Challenges (Frontier Simulations). A long-term strategy for the development of an Earth System Modelling capacity is also an objective of the project.

Human societies are facing grand challenges, which are expected to become even more prominent during the next decades – with climate change, availability of food, clean water and geoenergy resources being just some examples. In order to address these grand challenges, the scientific community needs to develop tools that provide decision makers with the information required to effectively manage these issues.

Earth system modelling is such a tool, as it enables investigating problems in an integrated manner considering interactions between different Earth system compartments and across scales – from local to global scales, and from weather time scales to millennia and beyond.

The ultimate goal of the project is to develop, evaluate and apply a world-leading Earth system modelling infrastructure —leading into an Earth System Simulator— to provide solutions to grand challenges faced by the Earth and environmental sciences.
Scientific and technical activities—the Scientific-technical Core—lie at the heart of the project. These include Earth System Model Development (WP1), the establishment of Earth System Data Assimilation (WP2) capacity as well as the development of an Earth System Diagnosis (WP3) framework. It is this Scientific-technical core, which will be developed into the first version of the “Earth System Simulator” in PoF-IV. In order to push existing boundaries in numerical experimentation, Frontier Simulations will be carried out in WP4. These “community” simulations will contribute to solving some of the grand challenges faced by the Earth and environmental sciences. At the same time, these simulations serve as demonstrations of the capability of the Earth system model infrastructure. The scientifically focussed work will be flanked by a Strategic Development component (WP5) that will lead into a long-term Earth system modelling strategy as well as a concrete implementation plan for PoF-IV.

DWD Vertrag

Within the framework of further improvements of the community wave model WAM and the atmospheric model ICON, a detailed comparison between the roughness lengths obtained by WAM and ICON provides profound insight whether the use of the more realistic WAM roughness lengths over sea would be able to improve the operational weather forecast system of the German Met Service (DWD: Deutscher Wetterdienst). That presents a first step into the development of a future coupled system between ICON and WAM. Furthermore several new integrated wave parameters will be included in the official output list of the wave model WAM which are up to three different swell systems instead of a total swell only and the energy and momentum fluxes into the ocean that are required for coupling purposes with hydrodynamic models.
The contract is funded by the DWD.


The coastal area is the most productive and dynamic environment of the World Ocean with significant resources and services for mankind. JERICO-NEXT emphasizes that the complexity of the coastal ocean cannot be well understood if interconnection between physics, biogeochemistry and biology is not guaranteed. Such integration requires new technological developments allowing continuous monitoring of a larger set of parameters. In the continuity of JERICO(FP7), the objective of JERICO-NEXT consists in strengthening and enlarging a solid and transparent European network in providing operational services for the timely, continuous and sustainable delivery of high quality environmental data and information products related to marine environment in European coastal seas. Other JERICO-NEXT objectives include: Support to European coastal research communities, enable free and open access to data, enhance the readiness of new observing platform networks by increasing the performance of sensors, showcase of the adequacy of the so-developed observing technologies and strategies, propose a medium-term roadmap for coastal observatories through a permanent dialogue with stakeholders. Although JERICO-NEXT already includes industrial partners, it will be open to other research institutes, laboratories and private companies which could become associated partners to the project.

The HZG contribution to JERICO-NEXT is through its North Sea coastal observatory system COSYNA.
Furthermore, observation system assessments will be performed using numerical models. One particular focus is on HF radar systems.

WIPAFF “Wind Park Far Field”

Goal of the project

• The overarching project aims at delivering a contribution to reliable planning of offshore wind parks by analysing the impact of offshore wind parks in the North Sea on the regional wind field and climate.
• Completing, validating and applying numerical and analytical simulation models for offshore wind park wake far fields (10 to 100 km).
• Capturing and quantifying offshore wind park wakes far field effects by state-of-the-art in-situ, aircraft and satellite observations.
• Providing the basics for decisions on further planning and constructing offshore wind parks.
• Impacts which have an immediate influence on North Sea wind park yields and on the regional climate in adjacent coastal areas are in the focus of the investigations.

Partners in joint project

• Karlsruhe Institute of Technology (KIT)
o Institute for Meteorology and Climate Research – Atmospheric Environmental Research
• Technical University of Braunschweig
o Institute of Flight Guidance
• Helmholtz Centre Geesthacht, Centre for Materials and Coastal Research
o Institute of Coastal Research
• UL International GmbH
• University of Tübingen, Centre for Applied Geoscience


(Earth System Knowledge Platform) is a platform under development informing about risks and chances of global change in the environment. The scientifically validated and processed information comprising the topics water, ground, climate or natural disasters shall enable the society, policymakers and economy to make sound decisions on preventive future strategies. Besides 8 Helmholtz Centres further partners are engaged in the project. Funding is provided by the German Research Society (Deutsche Forchungsgemeinschaft) and the Ministry of Science and Culture of Lower Saxony.