TOWARDS PHYSICALLY CONSISTENT COPERNICUS IMAGING MICROWAVE RADIOMETER LEVEL 2 PRODUCTS FOR THE GLOBAL OCEAN AND ATMOSPHERE

R. Ekelund¹, C. Jimenez^2,3, E. Valido Cabrera¹, C. Prigent^3,2, F. De Angelis¹, J. Tenerelli⁴, F. Di Loreto¹, V. Mattioli¹, C. Accadia¹

¹EUMETSAT, ²Estellus, ³Observatoire De Paris, ⁴Ocean Data Lab

As part of the Copernicus component of the EU Space Programme, the European Space Agency (ESA), and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) are preparing for the expansion of the Copernicus Space Infrastructure with new observation capabilities including the development of a Copernicus Imaging Microwave Radiometer (CIMR). The primary objective of CIMR is to monitor ice in the polar areas, in support of the EU Arctic policy, and secondly to monitor land, ocean, and atmosphere parameters globally. The first satellite is planned for launch in 2029, followed by a recurrent unit planned for launch about 6 years later. The satellites will fly in sun-synchronous dawn-dusk orbits and observe using a 360 degrees conical scanning viewing geometry with a minimum of 1900 km swath width. Measurements are provided with full polarisation at L, C, X, K, and Ka bands.

Through a Contribution Agreement with the European Union, EUMETSAT was entrusted to contribute to the development of the CIMR global ocean and atmosphere Level 2 products. The current activities and status of the development at EUMETSAT will be presented, which considers the provisioning of the operational L2 processor, establishment of the ground segment infrastructure, and preparation for the validation activities.

The CIMR global ocean and atmosphere L2 products comprise the sea-surface temperature (SST), sea surface salinity (SSS), ocean wind vector (OWV), total column water vapour (TCWV), liquid water path (LWP), and liquid precipitation (PCP). The selected retrieval algorithm is a physically based optimal estimation algorithm that will ensure the physical consistency between the retrieved product variables.

The EUMETSAT ground segment will feature an interface with ESA’s Copernicus Space Component (CSC) Ground Segment for the collection of the L1 data needed to generate the global ocean and atmosphere L2 products for further archiving and dissemination to the users, in compliance with the mission availability requirements.

The validation framework will consider collocations with ECMWF model analysis data, Argo profiling floaters, drifting buoys, and reference satellite data. Of significant interest is the potential synergy with Metop-SGB that will carry the MicroWave Imager (MWI), the Ice Cloud Imager (ICI), and Scatterometer (SCA). Thanks to their synchronized orbits, collocated observation within 10 minutes at the poles will enable inter-satellite comparisons of their respective wind and atmospheric products. Moreover, utilizing the full frequency spectrum from 1.4 GHz to 664 GHz through passive radiometry, in synergy with active SCA observations, will enable unprecedented characterization of the surface-ocean-atmosphere system within the dynamic hotspot regions of the Poles.