LSTM Copernicus (Land Surface Temperature Monitoring) mission
LSTM is a next generation ESA mission within the Copernicus program to complement Sentinel observation capabilities with high spatio-temporal resolution TIR (Thermal Infrared) observations over land and coastal regions in support of agriculture management services,and possibly a range of additional applications and services. The primary objective is to enable monitoring the evapotranspiration (ET) rate at European field scale by capturing the variability of Land Surface Temperature (LST) (and hence derived ET) allowing more robust estimates of field-scale water productivity. 1)
Evolution in the Copernicus Space Component (CSC) is foreseen in the mid-2020s to meet priority Copernicus user needs not addressed by the existing infrastructure, and/or to reinforce services by monitoring capability in the thematic domains of CO2, polar, and agriculture/forestry. This evolution will be synergetic with the enhanced continuity of services for the next generation of CSC.
The LSTM (High Spatio-Temporal Resolution Land Surface Temperature Monitoring) Mission”, identified as one of the CSC Expansion High Priority Candidate Missions (HPCM), currently undergoes an ESA preparatory phase (phase A/B1) study to establish mission feasibility.
The LSTM mission shall provide enhanced measurements of land surface temperature with a focus responding to user requirements related to agricultural monitoring.
The existing Copernicus space infrastructure, in particular Sentinel-1 and Sentinel-2, already provides useful information for agricultural applications. Although Sentinel- 3 already provides global LST measurements, the limited 1km spatial resolution does not capture the field-scale variability required for irrigation, crop growth modelling and reporting on crop water productivity. In view of the foreseen evolution in Copernicus, additional high-level observation requirements have been assessed and discussed at the EC Copernicus Agriculture and Forestry User Requirement Workshop in 2016, revealing the lack of European spaceborne capability for providing high spatio-temporal resolution Thermal Infrared (TIR) observations. 2)
Therefore, a dedicated LSTM mission is foreseen in the frame of the Copernicus evolution with the overall objective: To complement Sentinel observation capabilities with high spatio-temporal resolution Thermal Infrared observations over land and coastal regions in support of agriculture management services, and possibly a range of additional services.
The LSTM mission would deploy one or more satellites equipped with TIR instruments optimized to support agriculture management services with the specific mission objectives below. Based on the European and international policies the mission objectives are specified as:
• Primary objective: to support monitoring evapotranspiration (ET) rate at European field scale by capturing the variability of Land Surface Temperature (LST) (and hence ET) enabling more robust estimates of field-scale water productivity.
• Secondary objective: to support mapping and monitoring the soil composition (mineralogy and organic matter) and its dynamics through emissivity estimates.
• Complementary objective: to support a range of additional services benefitting from TIR observations (e.g. coastal zone management, High-Temperature Events (HTE), urban heat islands).
This Copernicus candidate mission will map every 1-3 days the surface temperature of planet Earth and rates of evapotranspiration – the water vapor emitted by growing plants – at 400 times finer resolution than currently measured from space. It will have a low-Earth polar orbit, with each pixel in its radiometer’s field of view representing a square of size 50 meters. The overpass time will be early afternoon and it will provide daily measurements from five bands in the thermal infrared spectral range 8 - 12.5 µm complemented by bands in the visible and near-infrared. ESA will provide level 2 data (with various corrections and calibrations applied) for land surface temperature, emissivity and bottom of atmosphere surface reflectance per spectral band, total column water vapor and cloud mask information, as well as lower-level products. 3)
Accurately tracking Earth’s temperature using satellite-derived information helps to explain the physics at the land-surface, including the processes driving energy and moisture exchange with the overlying atmosphere. Monitoring and understanding drought, changes in vegetation, heatwaves, urban heat island effects and the stability and extent of permafrost will all benefit from these data. The mission is focussed on addressing the priority requirements of the agricultural user community for improving sustainable productivity at the field-scale in a world of increasing water scarcity and variability caused by climate change. In particular, the daily evapotranspiration measures provided by LSTM will help farmers to manage irrigation regimes and optimize yield with minimum water supplies. LSTM’s thermal infrared sensing ability will also apply to sea and lake surface temperature monitoring: its high spatial resolution will be particularly useful for tracking small features such as lakes in the Arctic, coastal zones, rivers, coral reefs, ocean upwellings and structures such as oceanic eddies that influence vertical transport of nutrients, crucial for ocean productivity. In an urban context, LSTM will inform planning and ‘climate-adaptive’ building design to deal with heatwaves.
Figure 1: Images from JPL’s experimental ECOSTRESS mission, demonstrating future applications of the LSTM mission: latent heat flux from irrigated fields near Barrax, Spain in August 2018, and high urban surface temperatures in Rome, Italy during the heat wave of June 2019 (image credit: NASA/JPL)
• November 13, 2020: The European Space Agency (ESA) has selected Airbus Defence and Space as prime contractor for the new Land Surface Temperature Monitoring (LSTM) mission. LSTM is part of Copernicus, the European Union's Earth observation program for global monitoring. It is one of the six new missions, expanding the capabilities of the current Copernicus space component. The contract is valued at € 380 million which includes the development of one LSTM satellite, with an option for two further satellites. 4) 5)
- The main objective of LSTM is to deliver global high spatio-temporal day- and night-time land surface temperature measurements. Satellite data analysis for mapping, monitoring and forecasting the Earth's natural resources helps to understand what, when and where changes are taking place. In particular, this mission will respond to the needs of European farmers to make agricultural production on individual farms more sustainable, as water shortages increase and changes in the environment take place. Specialists will be able to calculate in real time how much water different plants require in different areas, and how often those plants need to be irrigated.
- Land-surface temperature measurements and derived evapotranspiration - the water vapor emitted by plants as they grow - are key parameters to understand and respond to climate variations, manage water resources for agriculture, and predict droughts. Thermal infrared observations will support a range of additional services to address land degradation, soil composition, natural hazards such as fires and volcano activity, coastal and inland water management as well as urban heat island issues.
Figure 2: Artist's rendition of the deployed LSTM spacecraft (image credit: Airbus)
Jean-Marc Nasr, Head of Space Systems at Airbus said: “Measuring surface temperatures will help make agricultural production more efficient across the planet, benefitting us all. With Airbus on board all Copernicus Sentinel satellites to date, we are delighted that ESA is further entrusting us with this next generation mission for the world’s most ambitious Earth observation program. This contract again confirms Airbus’ position at the forefront of space technologies for Earth observation and as the world’s n°1 exporter.”
LSTM will operate from a low-Earth, polar orbit, to map both land-surface temperature and rates of evapotranspiration with unprecedented field-scale detail. It will be able to identify the temperatures of individual fields and image the Earth every three days at 50 m resolution. This is about 400 times more detail than is currently acquired from space. Its observations will cover a wide temperature range, from approx. -20°C to +30°C, with very high precision (0.3°C).
LSTM is the first Copernicus mission awarded to a Spanish company and the third ESA mission to be primed by Airbus in Madrid after the successful in orbit delivery of Cheops, the exoplanet hunter, and SEOSAT-Ingenio which is ready for launch. Being selected to lead this mission is a major milestone for space in Spain and again demonstrates ESA’s confidence in Airbus as a strong partner to prime ESA missions. The industrial consortium comprises more than 45 companies and institutions from up to 18 different countries. The support of the Spanish delegation to ESA was key in reaching this achievement.
Airbus has complete responsibility for the entire LSTM. It will design and build the LSTM satellite in Madrid, while the development and production of the advanced technology instrument will be carried out by Airbus in Toulouse.
The optical instrument flown on the LSTM satellite leverages Airbus’ latest innovations from programs such as the Franco-Indian TRISHNA mission to offer a best-in-class instrument. It will acquire images in Very Near Infrared, Short Wave Infrared and Thermal Infrared. With a four day revisit capability, the satellite will fly over European latitudes when the sun, and consequently stress on crops, are at their highest, to facilitate evapotranspiration measurement.
Overall, Airbus is responsible for the spacecraft or payload on 3 of the 6 new generation Copernicus Environment and Earth observation missions: LSTM, CRISTAL and Rose-L, and is providing critical equipment to all six.
Table 1: Plans for a New Wave of European Sentinel Satellites 6)
1) Benjamin Koetz,Wim Bastiaanssen,Michael Berger,Joris Blommaert,Pierre Defourney,Umberto DelBello,Matthias Drusch,Mark Drinkwater,Ricardo Duca,Valerie Fernandez,Ferran Gascon,Darren Ghent,Radoslaw Guzinski,Jippe Hoogeveen,Simon Hook,Yann Kerr,Jean-Pierre Lagouarde,Ilias Manolis,Philippe Martimort,Andrea Marini,Jeff Masek,Michel Massart,Massimo Mementi,Claudia Notarnicola,Marcello Sallusti,Inge Sandholt,Jose Sobrino,Peter Strobl,Thomas Udelhoven, ”High Spatio- Temporal Resolution Land Surface Temperature Mission - a Copernicus Candidate Mission in Support of Agricultural Monitoring,” IGARSS 2018 (IEEE International Geoscience and Remote Sensing Symposium), 22-27 July 2018, Valencia, Spain, https://ieeexplore.ieee.org/document/8517433
2) Joseph G. Alfieri, Martha C. Anderson, William P. Kustas, & Carmelo Cammalleri, 2017. “Effect of the revisit interval and temporal upscaling methods on the accuracy of remotely sensed evapotranspiration estimates.” Hydrology and Earth System Sciences, Volume 21(1) 2017, pp: 83–98, https://doi.org/10.5194/hess-21-83-2017
3) ”Plans for a New Wave of European Sentinel Satellites,” ESA, 2020, URL: https://futureearth.org
”Airbus wins ESA’s LSTM temperature-check mission for
Copernicus next generation,” Airbus Press Release, 13 November
2020, URL: https://www.airbus.com/newsroom/press-releases/en/
5) ”Contracts signed for three high-priority environmental missions,” ESA Applications, 13 November 2020, URL: https://www.esa.int/Applications/Observing_the_Earth/
6) ”Plans for a New Wave of European Sentinel Satellites,” ESA, 2020, URL: https://futureearth.org
The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (firstname.lastname@example.org).