MRI: Development of Enhanced T-Probe for Aircraft Measurement of Mixed Phase Ice-Water Cloud

Nevada System Of Higher Education, Desert Research Institute, Reno NV

Investigators

Abstract

This Major Research Instrumentation development project will significantly extend the operating characteristics of a recently developed instrument, the T-probe. This is an instrument to measure liquid water and ice content of clouds. In the current configuration, three collocated but separate sensors measure liquid water, and ice and liquid water combined (the difference giving the ice content), together with reference air speed and density. The instrument will be improved by increasing power availability, leading to more than doubling the present measurement limit of ice/water content to beyond two grams per cubic meter. Most important, this improvement also will include indication of shedding of excess water or ice when the probe is overwhelmed by high concentrations of liquid and/or ice particles. A video microscope will be employed to visually confirm the fate of collected particles as they strike the probe. Following completion of development and initial testing, the modified T-probe will be field tested under separate funding. This project will be a collaboration of discipline scientists, engineers, and the private sector. Intellectual merit: Mixed-phase microphysical processes lead to ice-phase precipitation, electric-charge separation, enhanced chemical reactivity, and an environment conducive to enhanced aircraft structure and engine icing. The interface between all liquid water and all ice in clouds may be only a few tens to a few hundreds of meters in thickness. High resolution measurements using the T-probe are critical to verify cloud composition on scales characteristic of these transition regions. Improvement in spatial resolution to less than 10 meters can be achieved by the proposed modifications. Broader impacts: Development and use of this instrument is ideally suited for graduate student training in an instrument class at both advanced undergraduate and graduate levels. Experiences from the project will be employed in a University of Nevada, Reno course regularly taught by the PI (ATMS 748) to 10-15 students per semester. T-probe development will provide opportunities for students to follow an idea through construction, testing, aircraft deployment, and application to new exploration. Beyond the classroom and beyond the atmospheric research issues previously mentioned, better characterization of mixed phase cloud conditions will result in improvements in aviation safety.