N25A-T025 TITLE: Expendable Air-sea Profiling Observations in Hazardous Weather Conditions

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Integrated Sensing and Cyber;Sustainment;Trusted AI and Autonomy

OBJECTIVE: Develop an improved lower atmospheric observing capability that is hardened for hazardous weather environments to better capture vertical, horizontal, and temporal variations in atmospheric profiles of dynamics and thermodynamics to the air-sea interface compared to standard radiosonde profiling.

DESCRIPTION: Accurate assessment of the environment is a critical prerequisite for forecasting future environmental states and decision making from those forecasts. Remote and hazardous operating environments are among the most challenging to observe and constrain in a forecast system. Understanding and analyzing hazardous weather conditions, such as convective precipitation and tropical cyclones, as well as complex air-sea interactions such as sea ice formation and break-up in marginal ice zones, remain particularly difficult. Although recent initiatives have aimed to enhance the quality and accuracy of environmental observations (see References), operational meteorological and oceanographic (METOC) agencies still rely heavily on legacy profiling and remote sensing techniques. There is often insufficient quantity of observations due to cost per unit as well as quality of data due to the operating environment difficulties on the sensors. This STTR topic aims to build on these recent efforts by developing advanced observing technologies that can provide higher-quality data, complementing existing METOC systems in challenging environments.

This STTR topic solicits novel research for the development of a robust technological candidate aimed at improving expendable profiling of air-sea phenomena in hazardous weather conditions. In particular, a compact, easily deployable, and competitively priced alternative to radiosondes is sought that will provide a higher quantity and quality of air-sea interface related observations in areas such as tropical cyclones and polar lows where more precise information of dynamic and thermodynamic properties such as surface drag and fluxes can be constrained. Proposed work should clearly indicate where the effort will expand beyond current radiosonde capability in one or more of the following: spatial observations, temporal observations, sampling rate, price per unit, durability in hazardous conditions, uncertainty characterization, and ability to target/collocate with other observational platforms. The performer should also aim for a production schedule that allows for the prototyping dozens or even hundreds of units during the validation phase, with the potential to scale up to larger operational thresholds for commercialization or transition.

PHASE I: Determine technical feasibility for improved expendable in-situ profiling observations in hazardous weather conditions of dynamics and thermodynamics influenced by air-sea interactions. Perform background review of strengths and limitations of current observing platforms with an emphasis on measurement uncertainties and logistical challenges. From related operational and research work in this area, identify and design an improved concept of measurement techniques that include novel approaches to addressing the limitations identified in the review. Where appropriate, perform a comparative analysis with current state-of-the-art platforms (such as radiosondes or well calibrated remote sensing) including uncertainty specifications and real-world results from validated field efforts. Required Phase I deliverables will include a report on the state of the science, an overview of previous/current concepts of operations and their accuracy, and the proposed engineering, hardware, software, and/or platform upgrades that will enhance precision, accuracy, and/or quantity of air-sea in-situ observations in challenging environmental conditions. In particular, reporting must include a discussion of how the proposed effort will uniquely enable new environmental observations as compared to radiosondes and must include a comparison of strengths/weaknesses in cost, longevity, sampling rate, and spatial/temporal coverage.

PHASE II: Using results from the Phase I, proposed effort should develop, fabricate, demonstrate, validate, and iterate on expendable profiling technology. Work in the Phase II should particularly focus on calibration and demonstration of improved observational accuracy in hazardous weather conditions. Multiple development spirals of improved engineering prototypes and real-world demonstration in conjunction with currently used sensing technologies are needed to understand sensor characteristics and robustness in desired conditions. To the extent possible, technology deployment should leverage existing systems for ground, ship, and/or aircraft-based delivery mechanisms, thereby supporting comparative calibration/validation metrics and facilitating transition from a prototype to operational system. Part of this effort must also include data ingest and assimilation into operational forecast models with a comparative analysis of added value and analysis/forecast improvement. Phase II work should use multiple prototype demonstration efforts to refine and focus innovative measurement aspects and improve data measurement quality, in addition to refining the concept of operations and solidifying the observational niche of the proposed technology.

PHASE III DUAL USE APPLICATIONS: Phase III work should build upon the previous prototyping and demonstrations to effectively prove the operational concept and mature the technology into a new expendable profiling platform that can be commercialized. The technology must be calibrated and validated in real world conditions and compared to observations that are currently used in an operational meteorology and oceanography environment, such as in-situ stationary platforms, other expendable data, and remote sensing. The expected state of the technology should be a system that can deploy and track observations in real-time of expendable sensors from ground, ship and/or via aircraft. Success rate must match that of currently operational radiosonde technology, with improvements in specific hazardous weather conditions (such as tropical cyclones, polar lows, heavy convective precipitation, large wave events) with a demonstrated decrease in failure rates and modes. Final transition/commercialization will entail regular production of well characterized sensors that can be deployed operationally and in field missions for targeted air-sea profiling observations to be transmitted and used in real-time for environmental forecast and analysis.

REFERENCES:

1. Nelson, T. C.; Harrison, L. and Corbosiero, K. L. "Temporal and Spatial Autocorrelations from Expendable Digital Dropsondes (XDDs) in Tropical Cyclones." J. Atmos. Oceanic Technol., 37, 2020, pp. 381-399. https://doi.org/10.1175/JTECH-D-19-0032.1

2. Cione, J. J. et al. "Eye of the Storm: Observing Hurricanes with a Small Unmanned Aircraft System." Bull. Amer. Meteor. Soc., 101, 2020, pp, E186-E205. https://doi.org/10.1175/BAMS-D-19-0169.1

3. Lee, Craig M. et al. "Emerging technologies and approaches for in situ, autonomous observing in the Arctic." Oceanography 35.3/4, 2022, pp. 210-221. https://www.jstor.org/stable/27182719

4. Holbach, Heather M. et al. "Recent advancements in aircraft and in situ observations of tropical cyclones." Tropical Cyclone Research and Review 12.2, 2023, pp. 81-99. https://doi.org/10.1016/j.tcrr.2023.06.001

5. Poulsen, Ebbe et al. "Uncrewed aerial vehicle with onboard winch system for rapid, cost-effective, and safe oceanographic profiling in hazardous and inaccessible areas." HardwareX 18, e00518, 2024. https://doi.org/10.1016/j.ohx.2024.e00518

6. Abdunabiev, Shahbozbek et al. "Validation and traceability of miniaturized multi-parameter cluster radiosondes used for atmospheric observations." Measurement 224, January 2024, 113879. https://doi.org/10.1016/j.measurement.2023.113879

KEYWORDS: Radiosonde; expendable; profile; meteorological and oceanographic; METOC; meteorology; oceanography; autonomous; temperature; humidity; wind; flux; marine atmospheric boundary layer; tropical cyclone; polar low

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