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Hybrid Meeting "2nd GNSS Polarimetric Radio Occultations User Workshop" What: Over 80 people from 14 countries, 3 continents, and over 40 different affiliations, from government agencies, research centers, universities, and the commercial space sector, discussed the status of the polarimetric radio occultation technique and applications being developed from the current and future observations, with focus on its use for and in numerical weather prediction modeling. When: 28-29 November 2023 Where: Hybrid, at the Keck Center, California Institute of Technology, Pasadena, California. Co-organized by JPL and ICE-CSIC/IEEC. KEYWORDS: Atmosphere; Cloud microphysics; Convective-scale processes; Thermodynamics; Numerical weather prediction/ forecasting; Convective parameterization, 1. Introduction Conventional radio occultations (ROs) track the phase delay induced by water vapor and air density gradients in Global Navigation Satellite System (GNSS) signals as they propagate through Earth's [...]

Global Navigation Satellite System Interferometric Reflectometry (GNSS‐IR) measures water level using the interference pattern in signal‐to‐noise ratio (SNR) from direct and reflected signals off the sea surface, retrieved from standard geodetic antennas. Significant wave height is also measured by determining the satellite elevation angles where reflections become incoherent. We developed an approach for standard geodetic antennas to simultaneously measure sea levels and waves using a criterion for identifying coherent reflections. We tested the method at an exposed coastal environment at the E.B. Scripps Memorial Pier in California. The 1‐year test captures a broad range of sea states and benefits from several co‐located standard oceanographic sensors. By including GPS, Galileo, and GLONASS observations, the retrieval rate increases by a factor of ∼2 over GPS alone. Uncorrected water levels are estimated with a root‐mean‐square (RMS) error of 18.2 cm with respect to a conventional tide gauge. We further developed a simplified correction to remove the effect of phenomena altering the SNR oscillatory frequency and phase, which reduces RMS errors to 9.4 cm. We estimate the significant wave height with 15 cm RMS error with respect to a traditional wave gauge. The method, however, requires a short calibration. We find the wave height errors increase abruptly beyond a fixed limit when high waves are present, that may be a result of the particular deployment geometry. With this caveat, the technology could be useful to deploy in under‐sampled regions affected by compounded coastal hazards, such as in areas affected by tropical cyclones and flooding. Plain Language Summary: Signals from Global Navigation Satellite Systems (GNSS), such as the Global Positioning System (GPS), that reflect off the ocean surface, when compared to signals that arrive directly at the antenna, reveal variations in signal strength that can be used to determine the elevation of the ocean surface. When the satellite elevation angle is too high above the horizon, the method to measure sea level no longer works. However, observing the elevation angle where this transition occurs allows us to measure the height of the waves that are preventing a strong reflected signal from being recorded. We develop criteria for obtaining the closest agreement between the GNSS‐IR observations and the tide and wave gauge instruments on the Ellen Browning Scripps Memorial Pier in southern California over a 1 year period. Because it simultaneously measures changes in sea level and wave height, the method could be useful for measuring coastal hazards such as storm surge and flooding from hurricanes. Key Points: A new approach simultaneously estimates water level and wave height using Global Navigation Satellite System observations in the Pacific high wave coastal environmentLevels are determined with 9.4 cm error (RMS) and the astronomic tide (with a range over 2 m) is determined with 5.9 cm error, with respect to a traditional gaugeGiven a short calibration, significant wave height achieves an RMS error of 15 cm compared to a traditional gauge [ABSTRACT FROM AUTHOR]

The Pilliga Forest is one of the largest surviving woodland remnants on the New South Wales western slopes in inland eastern Australia. Collation of personal observations by a resident herpetologist working in the Pilliga Forest over a 12-year period identified 18 frog species and 49 reptile species. One additional reptile species was identified from museum specimen records, and unconfirmed reports of another one frog and seven reptile species are also noted. This paper provides the most comprehensive published account of the herpetofauna of the Pilliga Forest to date, and illustrates the value of observations over an extended period. Comparison with other locations across western New South Wales highlights the high species richness of the Pilliga Forest for both frogs and reptiles. This is in part a function of its location in a biogeographic overlap zone between eastern, western and northern faunal assemblages. Species of particular conservation concern found in the Pilliga Forest include the threatened Hoplocephalus bitorquatus, near-threatened Pseudophryne bibronii and declining woodland reptiles such as Ctenotus allotropis, Diporiphora nobbi, Morelia spilota metcalfei, Acanthophis antarcticus, Brachyurophis australis and Vermicella annulata. [ABSTRACT FROM AUTHOR]

Investigates the career and work perceptions of new teachers of varying promise and ability and the influence of new work structures on these perceptions. Findings suggest that teachers with high promise and ability make sense of their work using different criteria from teachers of lesser ability and promise. Discusses implications. (JS)

Current climate models have difficulty representing realistic wave-mean flow interactions, partly because the contribution from waves with fine-vertical scales is poorly known. There are few direct observations of these waves and most models have difficulty resolving them. This observational challenge cannot be addressed by satellite or sparse ground-based methods. The Strateole-2 long-duration stratospheric superpressure balloons that drift with the horizontal wind on constant density surfaces provide a unique platform for wave observations across a broad range of spatial and temporal scales. For the first time, balloon-borne Global Navigation Satellite System (GNSS) radio occultation (RO) is used to provide high vertical resolution equatorial wave observations. By tracking navigation signal refractive delays from GPS satellites near the horizon, 40-50 temperature profiles were retrieved daily, from balloon flight altitude (~20 km) down to 6-8 km altitude, forming an orthogonal pattern of observations over a broad area (±400-500 km) surrounding the flight track. The refractivity profiles show an excellent agreement of better than 0.2 % with co-located radiosonde, spaceborne COSMIC-2 RO and reanalysis products. The 200-500 m vertical resolution and consecutive sampling in time and space make it possible to extract properties of Kelvin waves to shorter period gravity waves with vertical wavelengths as short as 2-3 km. A short dataset from the extra Galileo and GLONASS constellations demonstrates the feasibility to nearly double the sampling density in planned follow-on campaigns. The results will contribute to improved estimates of momentum forces for wave driving of the Quasi-biennial Oscillation (QBO) and improved QBO representation in models, and illustrate the importance of measuring intrinsic period in the Lagrangian reference frame. [ABSTRACT FROM AUTHOR]