On the Romanian Danube sector in South-Eastern Europe, sand and ice banks can present difficulties for ships navigating these waters—Copernicus Sentinel satellite images are used by local authorities, to monitor navigation and manage traffic.

Navigation on the Danube River is often limited by the presence of sand banks (in dry summer periods) and ice banks (in very cold winters), phenomena that have an important impact on navigation safety, continuity and effectiveness of transport operations for goods and passengers.

In July–August 2015, most of Europe experienced daily temperatures above 34 - 35°C and absolute maximum values above 40°C in many areas (for instance, 46.2° C in Southern Romania).

Combined with a significant reduction of rainfall, this led to soil drought and low water levels of the Danube River. The low water level advanced the narrowing of the navigation route at Zimnicea (567 kilometres), causing ships to queue up before being able to cross the area.

The Romanian Lower Danube River Administration (AFDJ) and the Romanian Space Agency (ROSA) worked closely, to find a reliable solution for characterising the ship traffic on the Danube.

Thanks to ESA experts and mission managers, the first available images from the Sentinel-1 and Sentinel-2 satellites (the latter still in the commissioning phase at that time) of the European Union's Copernicus Programme were processed and sent to AFDJ.

Data were mainly used for identifying the crowded points on the Danube. Thanks to the satellite images from 2 and 9 of August, it became immediately obvious that many more ships were on the Danube than initially reported (some 100 or more ships), based on the AIS (Automatic Identification System) data.

The synergistic use of Copernicus Sentinel-1 and Sentinel-2 data allowed the Romanian Lower Danube River Administration to monitor navigation at critical points, such as those close to Zimnicea, until the end of the drought period.

Benefits of EO Data

Earth Observation data proved to be very useful in the continuous monitoring of vessel traffic, in order to avoid navigation problems. Such data can further improve the functionality of existing navigation systems, accuracy of sailing management information and dissemination of information.

The Copernicus Sentinel-1 mission comprises a constellation of two polar-orbiting satellites, operating day and night performing C-band synthetic aperture radar imaging, enabling them to acquire imagery regardless of the weather. The mission's ability to provide observation in all weather, and in day or night time conditions, makes it ideal for ship traffic monitoring.

Copernicus Sentinel-2 is a wide-swath, high-resolution, multi-spectral imaging mission, designed to give a high revisit frequency of 5 days. It carries an optical instrument payload that samples 13 spectral bands, which enables it to cover applications such as agriculture and forestry, land ecosystems monitoring, disaster management, humanitarian relief operations and risk mapping, along with maritime surveillance.

In 2017, AFDJ reported a significant increase in the number of ships transporting goods on the Danube – 1863 ships in 2017 compared to 1771 ships in 2016, which also means an increase of revenues for both the administration and the commercial sector.

Ioana Vlad Sandru, Research Scientist at the Romanian Space Agency, states, "The integration and use of Copernicus Sentinels, together with inland vessel traffic services, could prevent the development of dangerous vessel traffic situations by managing traffic movements, providing safety and efficient movement of vessel traffic, within the VTS area."

About the Copernicus Sentinels

The Copernicus Sentinels are a fleet of dedicated EU-owned satellites, designed to deliver the wealth of data and imagery that are central to the European Union's Copernicus environmental programme.

The European Commission leads and coordinates this programme, to improve the management of the environment, safeguarding lives every day. ESA is in charge of the space component, responsible for developing the family of Copernicus Sentinel satellites on behalf of the European Union and ensuring the flow of data for the Copernicus services, while the operations of the Copernicus Sentinels have been entrusted to ESA and EUMETSAT.