Research Flights Will Obtain Most Comprehensive Data Set To-Date for Climate Models

Summary

This week, DOE’s Atmospheric Radiation Measurement (ARM) Climate Research Facility began a five-month aircraft campaign to gather data from cirrus clouds in the skies above Oklahoma. Using an instrumented research aircraft, the goal is to obtain a new and comprehensive set of in-cloud measurements about the size and number of ice crystals that make up cirrus clouds. The reflective properties of ice crystals in cirrus clouds influence the amount of solar energy that reaches the Earth. Scientists use information about the shape and size of ice crystals as input to climate models. Data obtained by satellite instruments, ground-based sensors, and research aircraft equipped with probes have exhibited notable discrepancies leading to considerable uncertainty in how to represent these properties in climate models. This new field campaign, Small Particles in Cirrus, or SPARTICUS, will help resolve these discrepancies through the use of new probes purchased with Recovery Act funds and designed to minimize potential problems with shattering of larger crystals on the inlets of the older probes. By using both new and old probes scientists hope to compare new and old measurements and re-evaluate past data sets. Ultimately, this will lead to a better understanding of the radiative effects of cirrus clouds on global climate.