Results 41 to 50 of about 141 (127)

Comparisons between the WRF data assimilation and the GNSS tomography technique in retrieving 3-D wet refractivity fields in Hong Kong [PDF]

Annales Geophysicae, 2019
Water vapor plays an important role in various scales of weather processes. However, there are limited means to accurately describe its three-dimensional (3-D) dynamical changes. The data assimilation technique and the Global Navigation Satellite System (
Z. Xiong, B. Zhang, Y. Yao
doaj   +1 more source

Plate Divergence at the Krafla Volcanic System, Iceland: Insight From GNSS Geodesy and Sentinel‐1 Satellite Radar Interferometry in 2002–2024

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 8, August 2026.
Abstract The Krafla volcanic system in Iceland, a subaerial segment of the divergent boundary between the North American and Eurasian plates, offers a unique opportunity to investigate volcano‐tectonic processes. We present a six‐segment kinematic back slip plate boundary model constrained jointly by long‐term deformation velocity fields from Global ...
Yilin Yang, Freysteinn Sigmundsson, Halldór Geirsson, Juliet Biggs, Vincent Drouin, Josefa Sepúlveda‐Araya, Sigrún Hreinsdóttir, Chiara Lanzi, Joachim Gottsmann, Taco Broerse, Sandra Verhagen   +10 more
wiley   +1 more source

GAM-STTD: a spatiotemporal tropospheric delay correction model for time-series InSAR in complex mountainous regions

International Journal of Digital Earth
Tropospheric delay remains a critical error source in time-series interferometric synthetic aperture radar (TS-InSAR), particularly in mountainous and plateau regions where seasonal stratification and stochastic turbulence coexist.
Shipeng Guo, Xiaoqing Zuo, Jihong Zhang, Xu Yang   +3 more
doaj   +1 more source

3D Water Vapor Signature of Tropical Storms: GNSS Tomography of the 10 Most Severe Rainfall Events in Hong Kong 2015–2025

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 13, 16 July 2026.
Abstract Monitoring water vapor during extreme events is crucial for understanding atmospheric physics, as well as for improving the prediction of severe weather and enhancing early warning systems. The major gap in monitoring water vapor during extreme events lies in the limited spatial and temporal resolutions of existing techniques.
P. Mateus, D. Hui, M. Zhang, R. Fernandes, P. M. A. Miranda   +4 more
wiley   +1 more source

Analysis of Spatial and Temporal Characterization of GNSS Tropospheric Parameters During the Extreme Rainfall on ‘9.7’ in Hong Kong

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
On 7 September 2023, Hong Kong experienced a rare extreme rainfall due to the low-pressure trough associated with the remnants of Typhoon “Haikui,” which caused significant casualties and economic losses.
Ming Shangguan, Xiaomei Ren, Shuguang Wu, Huaiqi Ye, Wenkui Li   +4 more
doaj   +1 more source

MSWD: A Hybrid Machine‐Learning Framework for Slant Wet Delay Modeling

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 12, 28 June 2026.
Abstract Space geodetic techniques such as Global Navigation Satellite Systems (GNSS) and Very Long Baseline Interferometry (VLBI) are limited by direction‐dependent tropospheric delays, with slant wet delay (SWD) being the most variable component and a major error source.
Zhenyi Zhang, Benedikt Soja
wiley   +1 more source

GNSS Zenith Wet Delay as a Boundary Layer Diagnostic: Regime‐Dependent Turbulence Signatures From Large Eddy Simulation and Observations

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 12, 28 June 2026.
Abstract Global Navigation Satellite Systems (GNSS) provide continuous measurements of zenith wet delay (ZWD), reflecting column‐integrated atmospheric water vapor. While the slowly varying ZWD is routinely assimilated in numerical weather prediction, the rapid fluctuations on timescales of seconds to minutes that arise from boundary‐layer turbulence ...
Gaël Kermarrec, Tim Schrader, Xavier Calbet, Zhiguo Deng   +3 more
wiley   +1 more source

Regional Tropospheric Delay Prediction Model Based on LSTM-Enhanced Encoder Network

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Precise modeling of zenith tropospheric delay (ZTD) is essential for real-time high-precision positioning in global navigation satellite systems. Due to the stochastic variability of atmospheric water vapor across different regions, tropospheric delay ...
Yuanfang Peng, Chenglin Cai, Zexian Li, Kaihui Lv, Xue Zhang, Yihao Cai   +5 more
doaj   +1 more source

Three‐Year Characterization of Boundary Layer Dynamics From GNSS Zenith Wet Delay Spectral Analysis

Atmospheric Science Letters, Volume 27, Issue 6, June 2026.
Three years of GNSS zenith wet delay observations at Payerne reveal that spectral parameters—cutoff frequency α and variance σ2—capture robust seasonal cycles in boundary layer turbulence (R2 = 0.54 for α). Their inverse coupling tightens to r = −0.82 under summer convection, encoding regime‐dependent physics.
Gaël Kermarrec, Xavier Calbet, Zhiguo Deng   +2 more
wiley   +1 more source

Enhanced precipitable water vapor inversion and rainstorm monitoring based on GNSS PPP regional tropospheric modeling

Frontiers in Astronomy and Space Sciences
Precipitable water vapor (PWV) is critical for severe weather forecasting, yet existing GNSS Precise Point Positioning (PPP) retrieval methods are limited by neglecting tropospheric horizontal gradients and lacking regional coverage.
Ying Liu, Ying Liu, Yuze Yang, Kai Wang, Kai Wang, Weili Zhou   +5 more
doaj   +1 more source