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We present a new method using Global Navigation Satellite System‐derived peak ground velocities to rapidly determine rupture characteristics for large earthquakes (Mw > 6). A three‐step strategy is adopted to sequentially estimate the fault rupture length, direction, and pattern (unilateral or bilateral). It does not require any a priori constraint on the fault plane, and can avoid drift and clipping problems in seismic data based inversion methods. Through retrospective analysis of six recent large earthquakes, the line‐source rupture characteristics can be determined within 30 s. Comparison with the United States Geological Survey released products demonstrates that the line‐source parameters can be estimated with considerable accuracy. We also analyze the contribution of the earthquake rupture characteristics to the prediction of ground shaking intensity. It is shown that the method has the potential to improve ground shaking predictions with applications in disaster assessment and emergency response. Plain Language Summary: Rapid generation of ground shaking maps after an earthquake is of great importance to identify serious damage regions. Timely information of large earthquake rupture characteristics (e.g., rupture length, direction, and pattern) helps improve the estimates of ground shaking maps. The traditional methods to estimate the rupture characteristics can be hindered by the overdependence on seismic data that may be unreliable for displacement estimation in the near‐field of large earthquakes. We propose a new method of rupture characteristics estimation using geodetic velocity waveforms from Global Navigation Satellite System recordings. Our method does not require any pre‐defined fault geometric information and can avoid drift and clipping problems suffered in traditional methods. Through retrospective analysis of six recent large events, we show that the method can efficiently estimate line‐source rupture characteristics within 30 s with considerable accuracy. The estimates of the rupture characteristics can improve ground shaking predictions and are expected to be applied in disaster assessment and emergency response. Key Points: We propose a new method for the rapid inversion of large earthquake rupture characteristics using high‐rate Global Navigation Satellite System dataThe fault rupture length, direction, and pattern (unilateral or bilateral) can be rapidly determined with considerable accuracyThe estimates of the rupture characteristics are expected to refine ground shaking predictions for large earthquakes (Mw > 6) [ABSTRACT FROM AUTHOR]

Abstract: We present a new method of integrating Global Positioning System (GPS) and accelerometer data for high‐rate seismogeodesy. This method is based on the GPS variometric approach which can obtain seismic waves in real time using only the readily available broadcast products and a single receiver. Collocated 1‐Hz GPS and 200‐Hz accelerometer data from the 2016 MW 7.8 Kaikōura earthquake were analyzed to verify the effectiveness of this method. Results reveal that this method can provide broadband and more accurate velocities and displacements qualified to detect P wave arrivals. Moreover, this method can effectively avoid the aliasing problem present in the 1‐Hz GPS waveforms. We therefore conclude that this new method can be a powerful tool to capture seismic waves in real time, which is crucial for the purpose of tsunami early warning and earthquake rapid response. [ABSTRACT FROM AUTHOR]

As an attractive technique for measuring water vapor, the Global Navigation Satellite System (GNSS) faces additional challenges in dynamic applications such as in the open sea. We present a new method of retrieving precipitable water vapor (PWV) based on GNSS multi‐antenna precise point positioning (PPP), which uses GNSS data from multiple antennas and incorporates the constraints of known baseline vector and common tropospheric delay. The 4‐day shipborne dynamic experiment along the China coast demonstrates that the baseline vector constraint shortens the convergence time of positioning and atmospheric parameters, and also slightly improves their accuracies. The common tropospheric delay constraint helps to provide compromised, more robust, and sometimes more accurate PWV estimates. An evaluation with radiosonde‐derived PWVs shows that the combination of the two constraints achieves the best accuracy reaching 4.2 mm. This method helps to expand GNSS meteorology to the vast ocean and benefits satellite altimetry and weather forecasting. Plain Language Summary: Water vapor plays an important role in atmospheric processes ranging from global climate change to mesoscale and micro‐scale weather systems. The Global Navigation Satellite System (GNSS) is an attractive technique to measure water vapor, which has been extensively investigated for ground‐based static stations. In dynamic applications such as in the open sea, it is faced with additional challenges which may potentially degrade the performance. This study presents a new method for retrieving precipitable water vapor (PWV) based on GNSS multi‐antenna precise point positioning (PPP). It uses GNSS data from multiple antennas closely spaced and mounted on the same platform, and incorporates additional constraints of known baseline vector and common tropospheric delay. We have conducted a 4‐day shipborne dynamic experiment along the China coast and demonstrated that this method can shorten the convergence time and provide more robust and sometimes more accurate PWVs compared to conventional PPP. An accuracy level of 4.2 mm is achieved with this method for the ocean‐based dynamic experiment. This study helps to expand GNSS meteorology to challenging environments such as in the open sea, which will benefit weather forecasting and nowcasting. Key Points: A new method of retrieving precipitable water vapor (PWV) is presented based on Global Navigation Satellite System (GNSS) multi‐antenna precise point positioning (PPP)This method can shorten the convergence time and provide more robust and more accurate GNSS‐based PWVThe improved performance is helpful to expand GNSS meteorology to the vast ocean and benefits satellite altimetry and weather forecasting [ABSTRACT FROM AUTHOR]