Team: ESA and Copernicus Ground Segments

In the ESA project “Copernicus Data Space Ecosystem” (CDSE, since 2022) this team contributes to the Sentinel-1 On-Demand Data Production Service.

The team also supports the payload ground segment of the Copernicus Sentinel-5P atmosphere satellite by providing data delivery services. Using specially developed systems and interfaces, the processed Sentinel-5P data is made operationally accessible to ESA, the long-term archives (LTAs at DLR and with external partners) and to authorized data users.

Additional ground segment projects supported by the team include the hyperspectral EnMAP satellite and the CO2Image satellite that is currently in the design phase and which is expected to yield new insights into CO₂ distribution in the atmosphere.

Project D-PAF/D-PAC/MMFI (1991-2017)

In 2017 after 26 years the D-PAF/D-PAC/MMFI project was successfully concluded by the team. This project involved processing and archiving satellite data from the ERS and Envisat missions. Commissioned by ESA, the project ERS-1/-2 Envisat D-PAF/D-PAC (Processing and Archiving Facility/Center) existed without interruption since 1991. It began that year with the launch of the ESA ERS-1 satellite (in operation until 2000), whose payload data was also received at the DLR German Antarctic receiving station GARS O'Higgins. In the course of this project data from the ERS-2 satellite (1995 - 2011) and Envisat (2002 - 2012) were also processed.

Within the framework of the project, SAR data from the three named ESA earth observation satellites were processed, archived and made available to a worldwide user community, initially on physical media and later electronically. In addition to the SAR data another main area was atmosphere data recorded by a variety of science instruments including GOME on ERS-2 and GOMOS, MIPAS and SCIAMACHY on Envisat. For example, the data from the SCIAMACHY instrument made a significant contribution to monitoring the size of the ozone hole over the Antarctic. During the course of the project a total of 14 reprocessing campaigns for atmosphere data was carried out in order to adapt the data to the latest prevailing science data processors.

Data transfer technology has change over the years. What began with the shipment of CDs, DVDs and Exabyte media was adapted to FTP/HTTP servers starting in 2010. Each month up to 30 TB of data or up to a half-million data sets were delivered. Each year over 30,000 ESA orders were processed. ERS and Envisat data are still being used for research purposes by a global user community, long after the end of the active mission phases.

Starting in 2012, after the unexpected end of the Envisat-Mission, ESA began a data recirculation during which over 600 TB of ERS-1/-2- and Envisat data were extracted from DLR archives in order to make them available to users via ESA’s (A)SAR On-The-Fly Service. By the end of the project some 4.1 million data sets with over 800 TB of data had been extracted from the data archives.

Sentinel-1 Sentinel-3-OLCI PAC project (2012 - 2021)

After a configuration and start-up phase from 2012 to 2014, the Sentinel-1A Processing and Archiving Center (PAC) began operations at the beginning of 2015 on behalf of ESA. In 2016 the operational phase began for the Sentinel-1B satellite as well as for OLCI data from the Sentinel-3A satellite. Data from Sentinel-3B could be added to this supply in 2018. As impressive as the data yield from the three historic ESA missions (ERS-1/-2, Envisat) was, the fleet of Sentinel satellites collected earth observation data of a new order of magnitude. The four Sentinel satellites generated what was a dramatic increase in the amount of data to be processed and archived. During the six years of routine operation from 2015 to 2021, the Sentinel-1/3-OLCI PAC at EOC processed and archived almost 13.4 million data sets. The amount of data totaled over 16,900 terabytes (16.5 petabytes), thus surpassing by more than 20-fold the amount of data that had accumulated during the 26-year duration of the ERS-1/-2/Envisat project.

As one of the first institutions in Europe, DFD, supported by a dedicated team and other participants at the institute, became an official component of the Copernicus Sentinel payload data ground segment (PDGS). The Sentinel-1 Processing and Archiving Center began routine operations in March 2015. As a Processing and Archiving Center (PAC), DFD archived the data received at the Copernicus ground stations, systematically refined them to yield data products, and made them available worldwide to data users. The required infrastructure had been building up ever since the project began in 2012 and comprised a 2x 10 gigabit link to the Copernicus Wide Area Network. Up to ten terabytes of data, 6,000 data sets, were archived daily.

As part of a European network of seven PACs, DFD was responsible for processing, long-term archiving and distributing the Sentinel-1 radar images and the mid-resolution optical data from the Sentinel-3 mission (OLCI Sensor).

Starting in February 2020 the PAC at EOC had also taken over the responsibilities of a partner organization in Great Britain (UK-PAC) since ESA could not continue its operation because of Brexit. From that time DLR-PAC successfully carried the entire burden of Sentinel-1 data processing.

During the project contract period over 1.3 million data sets with a volume of almost 3 petabytes were retrieved from the DLR-PAC long-term archive (LTA) via the Copernicus Open Access Hub data portal.

In the final project year some of this data (5 million products with a data volume of 3,200 TB) was transferred from the DLR LTA to ESA’s successor projects.