Until recently, Copernicus Sentinel-5P depended on cloud masking information from another mission to produce high quality methane observations. Now Sentinel-5P’s methane processor has received a crucial update that enables it to independently generate these measurements, without relying on external cloud data.
Copernicus Sentinel-5P
Copyright:ESA
This upgrade has a number of important benefits, including allowing the processing of methane data in near real-time, in the near future.
Sentinel 5P’s methane product, second only to the nitrogen dioxide product, is among the mission’s most exploited datasets by the atmospheric user community. Monitoring of the gas is a priority for scientists because of its powerful heat trapping properties and its significant contributions to rising global temperatures.
Launched in 2017, Sentinel-5P is the first mission of the European Union’s Copernicus Earth Observation Programme dedicated to atmosphere monitoring and is currently the only satellite in orbit capable of measuring methane on a daily basis globally.
It has provided scientists with the possibility to detect methane hotspots on a global scale, transforming understanding of these emissions and advancing the international effort to address climate change.
The mission carries one sensor – named the TROPOspheric Monitoring Instrument (TROPOMI) – that detects the unique fingerprints of methane and several other important trace gases. It has a swath width of 2,600 km and maps the entire planet every day.
Sentinel-5P occupies a near-polar, sun-synchronous orbit, flying in loose formation with the Suomi-National Polar-orbiting Partnership (Suomi-NPP) satellite of NASA and the US National Oceanic and Atmospheric Administration (NOAA).
Suomi-NPP carries the Visible Infrared Imaging Radiometer Suite (VIIRS), which, amongst other observations, provides high resolution cloud masking information that is used to identify areas of satellite data obscured by cloud cover.
Suomi-NPP satellite
Copyright:NASA
Such information is vital for methane processing as cloud cover can interfere with methane retrievals, potentially leading to inaccurate data.
Sentinel-5P trails Suomi-NPP by about three-and-a-half minutes in the local time ascending node, meaning that VIIRS cloud data have good co-location with methane observations collected by TROPOMI. As a result, high resolution VIIRS cloud masking data can be used to account for cloud cover in the processing of TROPOMI data, ensuring that high-quality methane measurements are computed.
In the recent update to the Sentinel-5P methane processor, however, an artificial intelligence approach was applied to cloud data estimated from observations gathered by TROPOMI itself, enabling the independent production of the cloud information needed for methane processing. This means that VIIRS cloud data are no longer required for this application.
The capability of Sentinel-5P to autonomously produce methane measurements has several important implications.
Suomi-NPP launched in 2011 and is currently operated by NOAA on a best effort basis, meaning that in the event of a major failure no action will be taken to recover the situation. Consequently, Suomi-NPP could reach the end of its lifespan at any time. The Sentinel-5P methane processor upgrade will ensure TROPOMI can continue to deliver high-quality methane measurements even if VIIRS cloud data become unavailable to the user community.
The update to the Sentinel-5P methane processor will also enable the mission to process methane emissions in near real-time, as there is no longer a need to wait for the availability of VIIRS data. This is expected to open up several new operational and scientific opportunities.
Claus Zehner, ESA’s Mission Manager for Copernicus Sentinel-5P, comments, “The independence of Sentinel-5P methane processing from Suomi-NPP will soon allow ESA to provide methane product dissemination to users within a few hours after acquisition. This functionality was especially requested by the United Nations for its International Methane Emissions Observatory (IMEO) services on methane monitoring.”
Copernicus Sentinel-5P detects a methane plume over the US
Copyright:Contains modified Copernicus Sentinel data (2019-2020), processed by T. Lauvaux and Kayrros
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.
Did you know that?
Earth observation data from the Copernicus Sentinel satellites are fed into the Copernicus Services. First launched in 2012 with the Land Monitoring and Emergency Management services, these services provide free and open support, in six different thematic areas.
The Copernicus Atmosphere Monitoring Service (CAMS) provides continuous data and information on atmospheric composition. It supports many applications in a variety of domains including health, environmental monitoring, renewable energies, meteorology and climatology.