FORUM EARTH EXPLORER MISSION ADVISORY GROUP
DEADLINE FOR SUBMITTING YOUR APPLICATION
24 NOVEMBER 2025 – 23 JANUARY 2026 – 12:00 hrs noon (CET)
Submit your application for the FORUM Earth Explorer Mission Advisory Group here – [OPEN]
In order to submit your application, you need to be a registered user. To register or to log in to the site, please go to the Menu in the top left corner. Note that the last uploaded version of your application file (short CV and accompanying statement) to this Group membership application will replace any previously uploaded file on this system, and will be used by ESA for membership evaluation.
ANNOUNCEMENT OF CALL RESULTS
We shall evaluate all applications in Q1 2026.
FORUM EARTH EXPLORER MISSION ADVISORY GROUP OVERVIEW
This purpose of this call for membership of the FORUM MAG is to recruit scientific advisers to support the Earth Explorer mission for the next phase of development, i.e., Phases D/E1. The terms for FORUM MAG membership are laid out in the Terms of Reference (TOR). Members are expected to play an active role by giving expert advice regarding the activities needed to support development of the mission and will be selected on the basis of relevant scientific expertise. Currently the FORUM launch window is anticipated to start in 2028.
Far-infrared Outgoing-Radiation Understanding and Monitoring (FORUM) mission
The far-infrared (FIR) wavelength range plays a crucial role in determining Earth’s radiative balance. This knowledge is necessary for accurate climate modelling. Particular climate relevant processes that are active in the FIR are the water vapour greenhouse effect, the cirrus cloud greenhouse effect, and the surface emission in high latitude and high altitude regions. Recently, also the radiative impact of aerosols such as dust and ash has been noted due to new laboratory measurements.
The objective of FORUM is to evaluate the role of the FIR in shaping the current climate and thus reduce uncertainty on predictions of future climate change. With this, FORUM’s primary mission objectives are:
- Measure the spectral distribution of the Earth’s outgoing longwave radiation encompassing the FIR
- Evaluate the underlying spectroscopy and cloud models currently employed in the FIR
- Tie the observed radiative signatures directly to variability in, in particular, water vapour, greenhouse gases, cloud, aerosols, and surface properties
- Provide a stringent evaluation of key radiative processes/feedback mechanisms as currently represented in climate models.
The following FORUM Level 2 product retrievals are in various stages of development:
- Trace gas (water vapour, CO2, ozone, …) and temperature retrievals
- Detection of ice-cloud
- Retrieval of ice-cloud
- Retrieval of surface emissivity in appropriate conditions (clear-sky, dry conditions)
- Spectral fluxes
These retrievals will be performed for FORUM radiances only and for FORUM + IASI-NG radiances to cover the full range of the outgoing longwave radiation.
The FORUM mission is based on a single Earth pointing satellite in a near-polar sun-synchronous orbit at an altitude of about 830 km altitude with 09:30 local time at descending node. The satellite will fly in loose formation (1 min temporal co-registration) with IASI-NG on MetOp-SG-A. The expected mission lifetime is five years. FORUM performs continuous step-and-stare nadir-looking observations of spectrally-resolved top of atmosphere radiances in the mid-infrared and FIR region of the spectrum. The primary instrument is the FORUM Sounding Instrument (FSI), a single-pixel Fourier Transform Spectrometer sampling the electromagnetic spectrum from 1600 cm-1 to 100 cm-1 (6.25 mm to 100 mm) with a spectral resolution better than 0.5 cm-1. The FSI ground pixel is round with a 15 km diameter and the spatial sampling distance is 100 km. The FSI pixel is co-located with the footprint of the FORUM Embedded Imager (FEI), a single-band-infrared-imager centred at 10.5 mm with a bandwidth of 1.5 µm, a footprint of at least 36 x 36 km2, and it is sampled with 0.6 km × 0.6 km ground pixels. The Far-infrared Outgoing-Radiation Understanding and Monitoring (FORUM) mission was selected as ESA’s 9th Earth Explorer in 2019. The mission is currently entering Phase D, with a launch window starting in 2028.
USEFUL RESOURCES
