PlanetiQ GNSS RO Capabilities with a Focus on the Lower Troposphere and Boundary Layer

PlanetiQ’s team of scientists and engineers has a long history of developing and applying radio occultation (RO) capabilities extending back to the days of Voyager and GPS-MET through COSMIC and COSMIC-2. Based on this experience, PlanetiQ has developed and is flying state-of-the-art GNSS receivers on smallsats acquiring RO data from the 4 major GNSS constellations: GPS, GLONASS, Galileo and BeiDou-3. We have thus far acquired more than 2 million RO profiles of the atmosphere and ionosphere beginning September 2021. We presently have two 2 satellites producing approximately 4500 RO per day with pole-to-pole coverage. Our next satellite, scheduled to launch in Feb 2025, will increase this to approximately 6700 RO per day. Tied to these data, we have contracts with NOAA, NASA and the USAF as well as commercial companies.

Our GNSS observing system is unique in that it acquires RO data with very high signal to noise ratio (SNR) RO. This high SNR, plus our high-performance reference oscillators, reduces noise which enables the RO profiles to extend to higher altitudes into the lower mesosphere.

The bigger advantage of the high SNR is for profiling the boundary layer and lower troposphere which the National Academy of Sciences (NAS) and NASA have identified as a key goal for weather climate and air quality monitoring, understanding, and forecasting. RO’s ability to vertically profile the shallow boundary layer from orbit, in any and all-weather conditions, across the globe, is unique and therefore important to achieving these goals. High SNR RO is critical for minimizing or eliminating biases in RO profiles of the lower troposphere and boundary layer (LTBL). This includes detecting ducting conditions which occur frequently particularly over the ocean which require special processing of the RO data to minimize biases and therefore knowledge of whether ducting is occurring.

We are focused on extracting RO profiles utilizing the high SNR RO observations to reduce biases and noise particularly in the LTBL and enabling that information to be utilized in NWP and reanalysis systems for weather, climate, and air quality. This includes fully recovering the large bending angles from the RO data which are thus far being underestimated, better extraction of the RO bending angle information with less noise, better uncertainty estimates needed to properly weight and maximize impact on weather forecasts and reanalyses for climate and improving the vertical resolution to determine the height of the boundary layer and profile the refractivity structure inside the boundary layer, across the globe.

We will provide an overview of PlanetiQ’s capabilities and our latest RO results.