Aerosols are tiny particles in the air that influence climate by scattering sunlight and changing clouds. We compared methods for separating these effects in two climate models and five climates. We found that methods assuming aerosol-free conditions can overestimate cooling from cloud changes, especially when aerosols lie above clouds. Differences also arise from cloud masking, when clouds obscure other changes in radiation. Our findings help improve estimates of aerosol effects on climate.

Satellite navigation can help measure water vapor, but most stations lack weather sensors. This limits accurate real-time estimates. We developed a method using artificial intelligence weather models to calculate two key atmospheric quantities locally and quickly anywhere. Tests with three models gave water-vapor errors below one millimeter for five-day forecasts, better than current methods. This can improve real-time weather monitoring and forecasts when more satellite data are used.

We use ground-based CO₂ measurements from urban background, regional background and high-altitude stations, together with satellite-derived column-averaged CO₂ observations, in a regional atmospheric inversion modelling framework to optimize CO₂ emissions over Greece. We demonstrate the capability of this framework to improve CO₂ emission estimates, while noting that expanded observational coverage would be needed for strong emission constraints, especially near the major CO₂ sources.

Satellite ozone observations have been considered poor predictors of ozone at ground level. Here we evaluate the ability of one satellite product to estimate ground-level ozone globally over 18 years. The satellite product shows a modest correlation with ground-level ozone that does not vary strongly with year, season, world region, or ozone level. Using a linear regression, we translate the satellite product into a global monthly ground-level ozone dataset for use in future data fusion studies.

Aerosols affect climate by scattering and absorbing sunlight and heat. Light detection and ranging instruments can track aerosol distributions, but turning their signals into atmospheric information depends on particle size, absorption, and humidity. We developed a ground-measurement method and tested it in Slovenia. The results provide optical constraints that support more reliable retrieval of aerosol profile information when different particle types are mixed.

We connect two very different types of precipitating stratocumulus cloud models. The first model is a high-resolution simulation that can realistically represent clouds. The second model is a simple, 1D equation that interprets clouds as prey and rain as the predator of clouds. We evaluate the extent to which a simplified cloud model can represent selected aspects of a realistic cloud simulation under different meteorological conditions, highlighting both successes and limitations.

This study provides definitive experimental confirmation from space that the observed impact of CO₂ growth on longwave spectral radiances, in the troposphere and stratosphere, follows theory and that the results are independent of CO₂ uncertainties. By refining and extending a new methodology that disentangles the observational effects of CO₂ on Earth’s longwave spectra, from temperature and water vapor, the results conclusively confirm a critical foundation of the science of global warming.