In addition to its close collaboration with the European Space Agency (ESA), the programme has the support of other major international organisations. These include the National Aeronautics and Space Administration (NASA), which contributes advanced technologies and satellite data; the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), which manages the meteorological data collected by satellites; and the United States’ National Oceanic and Atmospheric Administration (NOAA), which provides crucial data on the oceans and the atmosphere.
There is also no shortage of collaborations with national space agencies and research institutes around the world, which strengthen global data monitoring and analysis capabilities.
The Programme makes it possible to respond promptly to emergencies that may occur on our planet and to take preventive measures to mitigate the effects of climate change. Access to these data in real time supports scientific research and political and operational decisions worldwide.
The programme is structured into six projects called “sentinels”. Let us therefore look in detail at these futuristic environmental monitoring systems.
Sentinel-1: high-resolution radar monitoring
The programme opens with the launch of the Sentinel-1A satellite on 3 April 2014, with the aim of providing high-resolution radar images of the Earth’s surface. It is fundamental for environmental monitoring and emergency management thanks to its ability to operate in all weather conditions, both day and night.
On 25 April 2016 the second satellite, Sentinel-1B, was launched. Both
Both satellites are equipped with synthetic aperture radar (SAR), which allows them to penetrate cloud and darkness, providing continuous and reliable data.
It is reasonable to ask what these satellites are actually used for. Well, there are numerous operations in which, for example, Sentinel-1 has been fundamental, to cite just a few:
- It played a crucial role in monitoring ground movements caused by earthquakes. For example, the satellite provided detailed data on the 2014 Napa earthquake in California, helping scientists to better understand the impact of the event and to plan the emergency response.
- During the floods in Bosnia and Herzegovina and in Serbia in 2014, it provided rapid, detailed maps of the affected areas, facilitating rescue operations and crisis management.
- In 2017, it monitored the volcanic activity of Mount Agung in Bali, providing essential data for timely evacuations and for planning the response to the eruption.
- It contributed to the monitoring of oil platforms in the North Sea, identifying anomalous movements and preventing potential environmental disasters.
Sentinel-2: high-resolution multispectral imaging
This is a mission designed to provide high-resolution multispectral images of the Earth’s surface. Made up of two satellites, Sentinel-2A and Sentinel-2B, launched on 23 June 2015 and 7 March 2017 respectively, the mission has proved essential for environmental monitoring and the management of natural resources.
Here are some applications in which the project has been fundamental:
Sentinel-2 has revolutionised precision agriculture, providing detailed data on crop health. For example, multispectral images make it possible to detect water or nutrient stress in plants, allowing farmers to intervene promptly and optimise the use of water and fertilisers.
In areas such as California, Sentinel-2 images have been used to monitor water use in agriculture, helping to improve water resource management during periods of drought.
Sentinel-2 has been used to monitor deforestation in the Amazon, providing detailed data on the loss of forest cover. The multispectral images help to identify illegally deforested areas, facilitating intervention by the competent authorities.
During the fires in Australia and California, Sentinel-2 provided real-time images of the affected areas, helping with the planning of rescue operations and the assessment of damage.
Sentinel-2 has been used to monitor water quality in lakes and rivers, detecting algal blooms and pollutants. For example, the satellite monitored algal blooms in Lake Erie, providing crucial data for water resource management.
Sentinel-2 images are used to monitor coastal erosion, providing data for coastal protection and urban planning in vulnerable areas.
Sentinel-3: multi-instrument measurements for oceans and land
The mission aims to measure a wide range of environmental parameters, both on land and in the oceans. It uses a series of advanced instruments to provide precise and reliable data, crucial for environmental monitoring and the management of natural resources. Sentinel-3A was launched on 16 February 2016, followed by Sentinel-3B on 25 April 2018. Together, these satellites guarantee global coverage and frequent revisiting of the data collected.
Here are some applications:
Waters and oceans
Sea surface topography: measures variations in the height of the sea surface.
Sea and land surface temperature: provides data on the surface temperature of both the oceans and the land.
Ocean and land colour: detects the colour characteristics of the oceans and of emerged lands, essential for studies of marine and terrestrial ecosystems.
It supports ocean forecasting models by providing data on sea surface temperature and topography, essential for understanding ocean currents, circulation and phenomena such as El Niño.
Algae monitoring: ocean colour images make it possible to detect algal blooms, such as those that occur in the Gulf of Mexico, helping to prevent damage to the fishing industry and tourism.
Ocean warming: Sentinel-3 data are used to monitor the rise in ocean temperatures, a key indicator of climate change.
Energy balance: by measuring land and ocean surface temperature, Sentinel-3 contributes to studies of the Earth’s energy balance and the effects of climate change.
Land environmental monitoring
Sentinel-3 provides timely data on land surface temperature, useful for detecting and monitoring wildfires. During the major fires in Australia, Sentinel-3 data were fundamental for mapping the burned areas and coordinating rescue operations.
Sentinel-3 provided critical data during the floods in India in 2018, helping to monitor the extent of the floodwaters and to manage emergency operations.
Vegetation monitoring
Sentinel-3’s land surface colour data are used to monitor crop health and agricultural productivity. For example, in regions such as India, this information helps to predict crop yields and to manage water resources more efficiently.
Sentinel-3 monitors forest cover and detects changes in forest biomass, supporting sustainable forest management.
Sentinel-4: high-resolution geostationary atmospheric monitoring
Sentinel-4 will be launched with the aim of monitoring air quality, providing crucial data for environmental management and public health. This mission will focus on detecting the main trace gases and aerosols over Europe, supporting the Copernicus Atmosphere Monitoring Service (CAMS) with high spatial resolution and rapid revisit times.
Technical characteristics
- Geostationary orbit: Sentinel-4 will be mounted on a Meteosat Third Generation-Sounder (MTG-S) satellite, stationed about 36,000 km above the Earth, allowing continuous, real-time coverage of specific geographical regions, in particular Europe.
- On-board instruments: the payload will include a UV-VIS-NIR (Ultraviolet, Visible, Near-infrared) imaging spectrometer, which will measure reflected solar radiation and the thermal radiation emitted by the Earth.
- Data frequency: it will provide data every hour, an essential feature for air quality monitoring and forecasting.
Data collected
Sentinel-4 will monitor various atmospheric pollutants, including:
- Ozone (O₃): essential for monitoring the stratosphere and ground-level air quality.
- Nitrogen dioxide (NO₂): an important indicator of pollution caused by traffic and industrial activities.
- Sulphur dioxide (SO₂): relevant for monitoring volcanic and industrial emissions.
- Methane (CH₄): a potent greenhouse gas.
- Aerosols: particulate matter suspended in the air that can affect human health and the climate.
Practical applications
- Urban air quality
- Pollution monitoring: it will provide detailed, real-time data on air pollution in European cities, essential for implementing pollution reduction policies and warning the public of any breaches of air quality limits.
- Support for environmental policies
- Regulation and control: Sentinel-4 data will support European authorities in regulating polluting emissions and in monitoring compliance with environmental regulations.
- Scientific research
- Climate studies: the data collected will be used to study the effects of atmospheric pollutants on the climate and to better understand the chemical and physical processes taking place in the atmosphere.
- Natural resource management
- Weather forecasts: they will improve short-term weather forecasts, in particular with regard to the dispersion of atmospheric pollutants.
- Public health
- Health alerts: Health authorities will be able to use the data to issue early warnings and advise the public on measures to reduce exposure to air pollutants.
Collaborations and implementation
Sentinel-4 will be developed in collaboration with the European Space Agency (ESA) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), which will ensure the operational management and distribution of the data collected. These data will be accessible to a wide range of users, including researchers, policymakers and the public, making Sentinel-4 an indispensable tool for tackling the environmental challenges of our time.
Sentinel-5: global atmospheric monitoring
Sentinel-5 will be a crucial mission of the European Union's Copernicus programme, designed to monitor the global composition of the atmosphere and provide essential data on air quality and climate. This mission will measure trace gases and aerosols that affect public health and climate change.
Technical features
- Polar orbit: Sentinel-5 will be mounted on a second-generation MetOp satellite, orbiting the Earth along a polar trajectory to ensure global coverage.
- Advanced instruments: It will use the UVNS spectrometer (Ultraviolet, Visible, Near-infrared, Shortwave-infrared) to measure reflected solar radiation and emitted terrestrial radiation, detecting various atmospheric gases and aerosols.
Data collected
Sentinel-5 will monitor a wide range of atmospheric pollutants, including:
- Ozone (O₃): It will monitor the stratosphere and ground-level air quality.
- Nitrogen dioxide (NO₂): It will indicate pollution from traffic and industrial activity.
- Sulphur dioxide (SO₂): It will detect volcanic and industrial emissions.
- Carbon monoxide (CO): A toxic gas produced by incomplete combustion.
- Methane (CH₄): A powerful greenhouse gas.
- Formaldehyde (HCHO): Important for atmospheric chemistry.
- Aerosols: Particulate matter suspended in the air that can affect human health and the climate.
Practical applications
- Air quality
- Pollution monitoring: It will provide global data to monitor and manage air pollution.
- Smog forecasts: The data will be used to forecast smog episodes and to issue health alerts.
- Climate change
- Greenhouse gases: It will monitor greenhouse gases such as methane and carbon dioxide, contributing to climate change studies.
- Climate feedbacks: It will provide data to understand climate feedbacks and improve forecasts.
- Natural phenomena
- Volcanic eruptions: It will monitor emissions of volcanic gases such as sulphur dioxide.
- Forest fires: It will support emergency management during and after forest fires, monitoring carbon monoxide and other pollutants.
- Scientific research
- Atmospheric studies: The data will be used to study the chemistry and physics of the atmosphere.
Collaborations and implementation
Sentinel-5 will be developed in collaboration with ESA, the European Commission and EUMETSAT, which will ensure the operational management and distribution of the data. These data will be accessible to researchers, policymakers and the public, making Sentinel-5 an indispensable tool for tackling the environmental and health challenges of our time.
For more details, you can visit:
- Copernicus Programme - Sentinel-5
- ESA - Sentinel-5 Mission
Sentinel-6: altimetry measurements for oceans and climate
Also known as Sentinel-6 Michael Freilich, it is dedicated to altimetric monitoring of the oceans. The mission is a collaboration between the European Space Agency (ESA), the National Aeronautics and Space Administration (NASA), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) and the National Oceanic and Atmospheric Administration (NOAA).
It was launched on 21 November 2020 from Vandenberg Air Force Base in California, on a SpaceX Falcon 9 rocket. Sentinel-6B, its twin satellite, is scheduled for launch in 2025, ensuring data continuity for at least another decade.
The Sentinel-6 mission is designed to continue and improve the sea level monitoring begun by earlier missions, such as TOPEX/Poseidon and the Jason series. Its main objective is to measure changes in sea surface height accurately on a global scale, a fundamental piece of data for the study of climate change and for operational oceanography.
Instruments and technology
- Poseidon-4 radar altimeter: Measures sea surface height with millimetre precision.
- Advanced Microwave Radiometer: Corrects the measurements for the effects of atmospheric humidity.
- GPS and DORIS systems: Provide extremely precise positioning data.
Scientific objectives
Sea level measurements: Sentinel-6 provides detailed data on sea surface height, essential for monitoring sea level rise caused by climate change.
Operational oceanography: Altimetry data improve understanding of ocean currents, waves and tides, which is essential for oceanographic and weather forecasts.
Climate studies: Sentinel-6 contributes to studies of the Earth's energy budget, monitoring the distribution of heat in the oceans and providing crucial information for climate models.
Achievements and applications
Detecting sea level changes: Sentinel-6 has already begun providing critical data on sea level changes, contributing to a better understanding of the effects of global warming.
Support for coastal flood forecasting: The data collected help to predict and manage coastal flood risks, providing vital information for coastal communities.
Contribution to scientific research: Sentinel-6 data are used by scientists around the world to study phenomena such as El Niño and La Niña, analysing their implications for global weather conditions and marine ecosystems.
For more details, you can visit the following resources:
Other sources: https://www.isprambiente.gov.it/files/copernicus/CopernicusNationalUserForumPCM_Col.Puri.pdf
