Aircraft in-situ measurements from SOCRATES constrain the anthropogenic perturbations of cloud droplet number
Song, C., McCoy, D. T., McCoy, I. L., Brown, H., Gettelman, A., et al. (2025). Aircraft in-situ measurements from SOCRATES constrain the anthropogenic perturbations of cloud droplet number. Atmospheric Chemistry and Physics, doi:https://doi.org/10.5194/acp-25-16063-2025
| Title | Aircraft in-situ measurements from SOCRATES constrain the anthropogenic perturbations of cloud droplet number |
|---|---|
| Genre | Article |
| Author(s) | C. Song, D. T. McCoy, I. L. McCoy, H. Brown, A. Gettelman, Trude Eidhammer, D. Barahona |
| Abstract | Abstract. Aerosol-cloud interactions (ACI) in warm clouds alter reflected shortwave radiation by influencing cloud microphysical and macrophysical properties. The variable of state controlling ACI is the cloud droplet number concentration (Nd). Here, we examine the perturbations in Nd due to anthropogenic aerosols (ΔNd, PD-PI) using a perturbed parameter ensemble (PPE) hosted in the sixth Community Atmosphere Model (CAM6). Surrogate models are created for the CAM6 PPE outputs and are used to generate 1 million model variants of CAM6 by sampling 45 sources of parameter uncertainty. The range of uncertain physical parameters related to ACI are constrained with observations of aerosol and cloud properties from SOCRATES. The likely range of uncertain parameters and the associated range of ΔNd, PD-PI are more strongly constrained with observations of Nd relative to observations of cloud condensation nuclei. We conduct sensitivity tests of how constraints on ΔNd, PD-PI are affected by systematic uncertainties in observations and our limitations in our surrogate models created for CAM6 PPE outputs. Based on this, we provide guidance on the impact of reducing systematic uncertainty in airborne microphysical observations and in surrogate models. |
| Publication Title | Atmospheric Chemistry and Physics |
| Publication Date | Nov 19, 2025 |
| Publisher's Version of Record | https://doi.org/10.5194/acp-25-16063-2025 |
| OpenSky Citable URL | https://n2t.net/ark:/85065/d7br8xnj |
| OpenSky Listing | View on OpenSky |
| RAL Affiliations | HAP |