February 7, 2019
Web Feature

Applying a New Multi-Scale Aerosol Model

Representing aerosols on 1-kilometer cloud scale within a multi-scale modeling framework yields simulation improvement

Aerosol processes can be represented at cloud scale

Aerosol processes usually occur on a smaller scale than the grid size of most global climate models, making it difficult to predict aerosol effects on climate. Researchers developed a global model representing aerosol processes at cloud scale within a new multi-scale modeling framework.

The Science

Aerosols in the atmosphere play an important role in Earth's climate by absorbing and reflecting energy. However, estimating their effects on climate is challenging, as most aerosol processes take place at scales smaller than the grid size (typically 100 kilometers) of traditional global climate models (GCMs).

In this study, researchers from the U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL) modeled aerosols on a 1-kilometer scale—on par with clouds—for the first time in a GCM using the new multi-scale modeling framework (MMF).

The Impact

Current GCM treatments of aerosol processes at scales of 100 kilometers cause errors in modeled aerosol distributions. PNNL researchers found that a newly developed global model with aerosols represented on 1-kilometer scale improves many aspects of aerosol simulations. By applying the new treatment of aerosol processes at cloud scale, the researchers improved the representation of aerosol-cloud interactions in the model. This new multi-scale aerosol model provides a benchmark for global aerosol modeling.

Reference: G. Lin, S. J. Ghan, M. Wang, P-L Ma, R. C. Easter, M. Ovchinnikov, J. Fan, K. Zhang, H. Wang, D. Chand, and Y. Qian, "Development and evaluation of an explicit treatment of aerosol processes at cloud scale within a multi-scale modeling framework (MMF)." Journal of Advances in Modeling Earth Systems 10(7):1663-1679. DOI: 10.1029/2018MS001287.

Published: February 7, 2019

Research topics