Planetary Boundary Layer Incubation Study – Technology Survey


The 2017 National Academies of Sciences, Engineering and Medicine Earth Science and Applications from Space (ESAS) Decadal Survey selected the Planetary Boundary Layer (PBL) as an Incubation Targeted Observable. In this context, the Decadal Survey recommended the implementation of a PBL incubation program to accelerate the readiness of high-priority observables not yet feasible for cost-effective flight implementation. The PBL incubation program goals call for exploring next-generation measurement approaches that could be ready for spaceborne implementation within 10-15 years. Observing system architectures utilizing airborne observations, ground-based observations, modeling and data-assimilation are also being considered to complement space-borne remote sensing observations.

In line with the findings of the 2017 ESAS Decadal Survey, the Incubation study team has identified PBL thermodynamic profiles (temperature and water vapor) and PBL height as ‘Priority Targeted Observables’ that cut across the needs of many of the NASA Earth Science Focus Areas. To evaluate and inform preliminary PBL observing system architecture studies, the PBL Study Team is seeking input on mature and emerging technology and techniques that can serve future needs for the measurement of the following geophysical observables:

  • Vertical profiles of water vapor within the PBL in clear and cloudy conditions
  • Vertical profiles of temperature within the PBL in clear and cloudy conditions
  • Planetary boundary layer height

The measurement goals for the aforementioned geophysical observables are listed in Table 1 and represent a wide range of temporal and spatial scales necessary to address PBL science across Earth science disciplines. The broad nature of the observational goals accommodates the requisite sampling strategies for a diverse yet synergistic set of space-based remote sensing techniques such as active, passive, and occultation remote sensing. Airborne and surface based remote sensors with resolutions and accuracies approaching or exceeding the low end of the goals listed in Table 1 are critical for process studies and will help to bridge observational gaps resulting from space-based remote sensor limitations.

Synergistic measurements critical for PBL science include but are not limited to geophysical observables over land, ocean, and ice, such as surface fluxes of water and energy, aerosol and cloud properties, cloud liquid water path, cloud base, precipitation type and rate, and 3D horizontal wind vector measurements. Additionally, profile measurements of water vapor and temperature that extend above the PBL into the lower free troposphere are highly desirable for improved understanding of exchange processes. These additional synergistic measurements shall only be considered if they are measured in addition to one or more of the PBL priority targeted observables cited in Table 1 and do not add significant complexity to the measurement/instrument concept.

Table 1. PBL Observational Goals


The study team is requesting information on emerging (TRL2-5) measurement approaches and technologies to enable the highest possible vertical and horizontal resolution thermodynamic profiling within the PBL from space within the next 10-15 years and technologies that offer the potential to reduce the size, weight and power (SWaP) of established measurement techniques. Reduction in SWaP will play a critical role in establishing distributed constellations of observations to help significantly improve temporal coverage. Measurement approaches such as active optical and microwave, passive optical and microwave, and novel occultation geometries are currently being considered. The study team also solicits input on both emerging and mature (TRL ≥6) suborbital technologies that can complement space-borne remote sensing observations. The PBL technology survey has an emphasis in the following areas:

  • Space-Based Remote Sensing
    • Required technology advances to meet the observational goals listed in Table 1.
    • Current best estimate resource footprint such as size, weight and power envelopes.
    • Identification of key technical challenges and resources required to overcome those challenges.
  • Airborne Remote Sensing
    • Description of instrumentation, observables, measurement capabilities and platform compatibility for TRL≥6 instruments.
    • Synergies with space-based observations.
  • Surface Networks
    • Description of instrumentation, observables, and network infrastructure including data availability.
    • Synergies with space-based and airborne observations.
  • Information Science and Technology
    • New and innovative techniques for on-board/on-ground data processing and analysis.

Current technologies (≥ TRL 6) are those at a high level of maturity being operationally used in the relevant environment (space, airborne, or surface) in Earth observing systems.

Emerging technologies (TRL 2-5) are those at a lower level of maturity which have the potential to be used in future Earth observing systems.

NASA Technical Readiness Level (TRL) definitions are available at

Response Instructions

The chart templates for emerging and current technology submissions can be downloaded using the following links:

The templates indicate the types of information that the study team is seeking. Technologies of interest for the study are as follows:

  • Instrumentation - Including hardware or processing and analysis methods.
  • Information systems - Including hardware or software for assessment or operation of observing systems, sensor webs, modeling, multi-source data fusion or assimilation, analysis.

This information will aid the Study Team in identifying gaps in current observing capabilities and gathering information about emerging capabilities that would help close those gaps. Please e-mail your technology survey submissions to no later than October 30, 2020.

For questions regarding PBL Technology Survey submissions please email:

Only material suitable for full and open distribution shall be submitted. Submittals shall be considered approved by the providing organization to be suitable for full and open distribution. No proprietary, export controlled, classified, or sensitive material should be provided. Published material does not indicate an endorsement or guarantee funding.

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