Four Dimensional (4-D) Atmospheric Instrumentation

This SBIR Phase-II Proposal to the Office of Naval Research is for the development of a cloud droplet studies instrument. The instrument is based on laser diffraction principles wherein small-angle forward scattering by a droplet/particle is closelyrepresented by diffraction through an aperture of equal diameter. The instrument that we propose here is unique in that it covers a wider range of sizes than any prior technology instrument, and the size bins are equally spaced in log-space. Furthermore,the design simplifies the electronics and optics so that the core instrument is expected to weigh less than 1 pound. This core instrument will be encased in a streamlined pod for installation beneath aircraft wings. Data storage can be on-board theinstrument electronics, and/or at a remote computer within the aircraft (naturally, the former is preferred). In the Phase-I final report, we note completion of all tasks proposed in the Phase-I project. In this Phase-II, we shall develop a fully capableprototype, and do initial flight testing. In the ensuing period, extensive in-flight test and data collection is proposed. Cloud dynamics remains the single biggest uncertainly in global climate modeling. The measurement of clouds, including the clouddroplet size distribution and liquid water content are essential to furthering understanding of climate dynamics. The present sensor system replaces poorer and more expensive prior systems. This system will be extensively used not only in climate research,but also is applicable in other weather phenomena such as hurricanes, dust clouds and storms, atmospheric visibility, etc.