Results 41 to 50 of about 653 (164)
A comprehensive comparison of atmospheric mapping functions for GPS measurements in Egypt
The principal limiting error source in the Global Positioning System (GPS) is the mismodeling of the delay experienced by radio waves in propagating through the atmosphere.
Younes S. A., Elmezayen A. G.
doaj +1 more source
A new vertical reduction model for enhancing the interpolation accuracy of VMF1/VMF3 tropospheric delay products [PDF]
Grid-wise Vienna Mapping Functions 1 (VMF1) and Vienna Mapping Functions 3 (VMF3) tropospheric products are widely used to interpolate the a priori zenith hydrostatic delay (ZHD) and zenith wet delay (ZWD) over GNSS (Global Navigation Satellite Systems ...
P. Sun +8 more
doaj +1 more source
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 +3 more
wiley +1 more source
Green Emissions of Atomic Oxygen at Sprite Tops Explained
Abstract Green emissions from excited Oxygen in Sprite Tops (GhOSTs) are due to the 557 nm photons emitted from atomic oxygen (O) $(\mathrm{O})$ excited to the 1S state. In this work we compare the possible contribution of various mechanisms for excitation of O(S1) $\mathrm{O}({}^{1}S)$ under application of a lightning‐induced electric field to the ...
Brandon Smith +2 more
wiley +1 more source
Three‐Year Characterization of Boundary Layer Dynamics From GNSS Zenith Wet Delay Spectral Analysis
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 +2 more
wiley +1 more source
Determination of Tropospheric Parameters from ERA Surface Data for Space Geodetic Techniques
This study investigates methods of deriving meteorological parameters needed in space geodetic applications, from the surface data of the numerical weather model (NWM).
Wei Li, Yujin He
doaj +1 more source
Abstract High‐precision regional ionospheric correction products are essential for achieving accurate and fast‐convergence solutions in Precise Point Positioning Real‐Time Kinematic (PPP‐RTK). For users in low‐ and middle‐latitudes, PPP‐RTK server narrow‐lane (NL) ambiguity resolution (AR) typically requires more than 10 min, which largely affects the ...
Pan Li +6 more
wiley +1 more source
Alternative Strategy for Estimating Zenith Tropospheric Delay from Precise Point Positioning [PDF]
Abstract. This study considered zenith total delay (ZTD) estimation from precise point positioning (PPP) based on GPS only (PPP GPS), GLONASS only (PPP GLO), and GPS+GLONASS (PPP GPS+GLO) using both a conventional strategy when applying a model for the hydrostatic component with an estimation of the wet component and an alternative strategy.
Jareer Mohammed +3 more
openaire +2 more sources
Precise modeling of tropospheric delay and weighted mean temperature (Tm) is critical for Global Navigation Satellite System (GNSS) positioning and meteorology.
Zhangyu Sun, Bao Zhang, Yibin Yao
doaj +1 more source
GRENet: GNSS‐Enhanced Radar Extrapolation Network for Precipitation Nowcasting
Abstract Accurate precipitation nowcasting is one of the most challenging tasks in atmospheric sciences. The current methods of nowcasting primarily rely on inferring precipitation from radar reflectivity, which inevitably leads to uncertainties in forecasts due to the limitations of single radar data in capturing the detailed initial conditions of ...
Cuixian Lu +7 more
wiley +1 more source

