In an initiative to reduce uncertainty in both projections of cloud behavior and climate change, climate scientists at U.S. Argonne National Laboratory (ANL), Pennsylvania State University and the NASA Goddard Institute for Space Studies developed an improved approach to compare cloud models with observations from weather instruments. The result is the Earth Model Column Collaboratory (EMC2) modeling platform and weather instrument simulator.

Results generated by current climate models do not directly compare to those from radars, satellites and other sensors whose signals cannot directly detect key cloud parameters like liquid water content andStandard workflow of EMC2 utilization for direct comparison between observations and model output. Source: Israel Silber et al.Standard workflow of EMC2 utilization for direct comparison between observations and model output. Source: Israel Silber et al. number of drops. They instead detect microwave and visible light reflected by clouds and precipitation. As an instrument simulator, EMC2 can convert the more detailed model-simulated cloud parameters to these weather instrument signals. The tool also helps represent the spatial variability of cloud cover inside each grid cell on smaller scales like those covered by the weather instruments. This smaller reference point allows climate scientists to evaluate models more accurately.

The open-source software enables both researchers and the public to easily add, use and modify models and observations. ANL researchers plan to use EMC2 in collaboration with the U.S. Department of Energy’s (DOE’s) Energy Exascale Earth System Model (E3SM), a high-resolution model designed to examine the most detailed dynamics of climate-generating behavior. Using meteorological observations from one of DOE’s Atmospheric Radiation Measurement (ARM) programs, EMC2 will help climate scientists reduce uncertainties in rainfall predictions by improving the representation of thunderstorms in E3SM. In addition, EMC2 is currently being used to evaluate weather forecasts during the DOE ARM TRacking Aerosol-Cloud interactions ExpeRiment (TRACER).

To contact the author of this article, email shimmelstein@globalspec.com