Dynamical Emissivity for Microwave Radiance Assimilation in Regional NWP: Preparing for the Arctic Weather Satellite and EPS-Sterna

Stéphanie Guedj; Máté Mile; David Schönach; Magnus Lindskog; Susanna Hagelin; Adam Dybbroe

doi:10.16993/tellus.4117

Dynamical Emissivity for Microwave Radiance Assimilation in Regional NWP: Preparing for the Arctic Weather Satellite and EPS-Sterna

Tellus

Volume 78 (2026): Issue 1

By: Stéphanie Guedj , Máté Mile , David Schönach , Magnus Lindskog , Susanna Hagelin and Adam Dybbroe

Open Access

|Feb 2026

Abstract

Radiance observations from microwave sounders have become one of the most valuable sources of information that is used in Numerical Weather Prediction (NWP). However, uncertainties in the land (and sea-ice) surface modelization do not permit optimal use of channels that receive a mixed contribution from the surface and the troposphere (i.e., low-peaking channels). In the context of the preparation of the Arctic Weather Satellite (AWS) mission, the HARMONIE-AROME model was run to evaluate the impact of assimilating the low-peaking channels of existing instruments using the so-called “dynamic emissivity method.” The aim of this work was also to build the best possible version of HARMONIE-AROME data assimilation system (3D-Var and 4D-Var) before the launch of the AWS instrument that happened in August 2024 and to be ready to assimilate the data as soon as the instrument was declared operational in June 2025.

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Articles in this issue

DOI: https://doi.org/10.16993/tellus.4117 | Journal eISSN: 3035-9554

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Language: English

Page range: 22 - 46

Submitted on: Jun 11, 2025

Accepted on: Jan 23, 2026

Published on: Feb 17, 2026

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

Keywords:

Variational data assimilation,

surface emissivity,

satellite data,

microwave low-peaking channels,

Arctic Weather Satellite

© 2026 Stéphanie Guedj, Máté Mile, David Schönach, Magnus Lindskog, Susanna Hagelin, Adam Dybbroe, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 78 (2026): Issue 1