A lack of localized, current, and accurate information on temperature, water vapor, and liquid water from the lowest level of the atmosphere, i.e. the atmospheric boundary layer, is one of the most pressing problems of current meteorology and atmospheric science. This omission limits our understanding of the initiation of cloud droplets, ice crystals, and precipitation. More data on water vapor, temperature profiles, and liquid water amount from the lowest level of the atmosphere has the potential to improve our understanding of fundamental physical processes and to evaluate numerical models. Such models are used to assess the predicted impacts of local conditions to global and regional weather systems. More accurate data with higher vertical resolution can improve our prediction skills for extreme weather events. The proposed project will develop an advanced microwave sensor for ground-based water vapor and liquid water measurements. The Autonomous Profiling Radiometer (APR) resulting from this effort will be a robust, self-controlled, more accurate, and better calibrated microwave radiometer with improved sensitivity and vertical resolution. The APR will provide measurements of atmospheric water vapor path, liquid water path, and vertical profiles of tropospheric water vapor and temperature. Compared to currently existing technology, these measurements will be provided with improved robustness, accuracy, sensitivity, and greater temporal and vertical resolution. The APR will be designed to operate without user supervision, calibrating autonomously, and it will be capable of indicating potential drifts of its sensors. Our Phase I project will be focused on the APRs preliminary electrical and mechanical design. We will develop and bench test critical components of the sensors based on radiometer receivers. Improvements in local short-term weather forecasting have a wide-ranging economic impact. Such improved weather predictions will serve transportation (for example, airports, seaports), provide improved predictability of renewable energy availability, give longer warnings before severe events such as hail storms, flush floods, tornadoes, hurricanes, snow storms, and more. The APR will provide more accurate measurements with better vertical and temporal resolution to improve such forecasts.
