A Counter for Ice Nucleated in Contrails Homogeneously and Heterogeneously (CINCH2)

Future flight vehicles will be required to emit lower and potentially different types of gases and particles in order to be more environmentally responsible. Particles emitted from jet turbines serve as cloud nuclei, and changes in their microphysical properties will impact upper level cloud formation, including contrails, which represents the major impact of aviation emissions on atmospheric radiation balance (climate change). Investigations into the impacts of current and future aviation emissionsnbsp;mustnbsp;determine any changes in the degree to which emissions affect contrail formation, cirrus cloud formation, and their evolution over time. The SBIR project seeks to develop an instrument suitable for both ground-based emission measurements as well as in-flight, low-pressure measurements of the ice forming properties of particles emitted from jet engines, building on existing continuous flow diffusion chamber approaches. The new instrument, the Counter for Ice Nucleated in Contrails Homogeneously and Heterogeneously (CINCH2), will measure ice formation by exposing engine emission particles to a region of controlled temperature and water vapor supersaturation and measuring any ice crystals that form in those conditions. The CINCH2 approach is well suited for both ground-based and airborne-based measurements because it will benbsp;fast, relatively compact, and capable of reproducing the entire range of atmospheric conditions important for studying ice nucleation processes. Phase II work will develop and test major subsystems for sample conditioning, refrigeration, and ice crystal detection, and combine these into a portable prototype instrument. Our overall goal is to produce the first commercial instrument capable of measuring ice formation in contrail emissions, as well as be suitable for studying ice formation on naturally-existing airborne particles in cirrus conditions more broadly.