GeoRoundup: the highlights of EGU Journals published during December!

Each month we feature specific Divisions of EGU and during the monthly GeoRoundup we put the journals that publish science from those Divisions at the top of the Highlights section. During this month, we are featuring Atmospheric Sciences (AS), Geosciences Instrumentation and Data Systems (GI), and Tectonics and Structural Geology (TS). They are represented by the journals Geoscientific Model Development (GMD), Annales Geophysicae (ANGEO), Atmospheric Chemistry and Physics (ACP), Geoscientific Instrumentation, Methods and Data Systems (GI), and Solid Earth (SE).

Atmospheric Chemistry and Physics

Injection near the stratopause mitigates the stratospheric side effects of sulfur-based climate intervention – 18 December 2025

Injecting sulfur dioxide at 50 km – near the stratopause – offers a far safer and more effective climate intervention than conventional 25 km injection. Rapid downward–poleward transport distributes aerosols across 20–30 km, halving tropical stratospheric warming, reducing ozone recovery delays from decades to about 5 years, and enhancing global and polar cooling by over 20 %, while better preserving Arctic sea ice.

Constraining urban fossil fuel CO2 emissions in Seoul using combined ground and satellite observations with Bayesian inverse modelling – 19 December 2025

This study develops a high-resolution inverse modeling framework that combines ground-based and satellite CO2 observations to improve urban emission estimates in Seoul. By integrating atmospheric data and transport models, the research reduces uncertainties in CO2 emissions and reveals spatial and temporal patterns. The method offers a valuable tool for supporting climate policies and can be applied to other cities for better emission verification.

Annales Geophysicae

Global inductive magnetosphere-ionosphere- thermosphere coupling – 10 December 2025

The ionosphere is where Earth’s atmosphere overlaps with a gas of charged particles in space. There, collisions with neutral air and electromagnetic forces driven by the solar wind control plasma motion. We created a global model that includes magnetic induction, explaining how electric currents and fields change, offering a more accurate view of atmosphere–space coupling than conventional models based on electric circuits.

Atmospheric Measurement Techniques

Synergetic retrieval from multi-mission spaceborne measurements for enhanced aerosol and surface characterization – 17 December 2025

Biogeosciences

The influence of irradiance and interspecific differences on δ11B, δ13C and elemental ratios in four coralline algae complexes from Aotearoa, New Zealand – 5 December 2025

Orbital-scale variability in the contribution of foraminifera and coccolithophores to pelagic carbonate production – 12 December 2025

Water vapour dynamics as a key determinant of atmospheric composition and transport mechanisms – 16 December 2025

Earth Surface Dynamics

An extrapolation algorithm for estimating river bed grain size distributions across basins – 18 December 2025

Hydrology and Earth System Sciences

How do geological map details influence the identification of geology-streamflow relationships in large-sample hydrology studies? – 15 December 2025

Natural Hazards and Earth System Sciences

Constitution of a multicentennial multirisk database in a mountainous environment from composite sources: the example of the Vallouise-Pelvoux municipality (Ecrins, France) – 10 December 2025