Automated Ceilometer for Ocean Meteorology (ACOMET)

The impact of maritime systems, especially the interaction of aerosols and cloud evolution, on climate change, and the inverse, is now a key focus area for improvement of climate change models. Several programs are either active or planned to leverage the commercial cargo fleet by deploying specialized instrumentation suites to gather meteorological data to advance the capabilities of weather predictive and climate change models. The height of the atmospheric boundary layer, for example, is used to parameterize boundary layer transport in numerical weather prediction models and is a key factor in the interaction of aerosols and cloud evolution. Increased knowledge of boundary layer structure drives the desire to add the capability to monitor this height to networks. The overall objective of the Phase I and II projects is to demonstrate a compact ceilometer designed specifically for operation in a maritime environment aboard commercial cargo vessels for extended periods. The proposed system incorporates a laser operating at an eye-safe wavelength and uses state-of-the-art techniques for ruggedization and stability in environmental extremes. The objective will be reached through modeling, engineering design, laboratory experiments, and field testing of prototypes. A specialized retrieval algorithm, freely available from the scientific community, will be incorporated into the sensor package to increase the number of data products available from a traditional ceilometer. In the Phase I program, system designs will be developed for a compact ceilometer that is deployable at sea on commercial cargo vessels for extended durations. A risk reduction effort using a breadboard pre-prototype in combination with specialized processing algorithms will demonstrate retrieval of aerosol related data products in addition to boundary layer height, thus demonstrating the feasibility of the design. The compact ceilometer will enable measurements of marine boundary layer heights and cloud ceilings on a wider scale and at higher frequencies than are possible now when deployed onboard the commercial cargo fleet. Such measurements are fundamental to improving our understanding of the complex couplings between the surface and clouds in the lower atmosphere and will ultimately help evolve models used in both weather forecasting and climate change prediction. The sensor is adaptable to deployment in other network venues, e.g., untowered airports, to provide improved weather data to general aviation pilots.