Results 61 to 70 of about 5,886 (223)

Impact Analysis of processing strategies on Long-term GPS ZTD

, 2023
Abstract. Homogenized atmospheric water vapor is an important prerequisite for climate analysis. Compared with other techniques, GPS has inherent homogeneity advantage, but it still requires reprocessing and homogenization to eliminate impacts of applied strategy and observation environmental changes where a selection of proper processing strategies is
Jingna Bai, Yidong Lou, Weixing Zhang, Yaozong Zhou, Zhenyi Zhang, Chuang Shi, Jingnan Liu   +6 more
openaire   +2 more sources

TOMO4D Operator for Assimilation of GNSS Tomography‐Derived Water Vapor Fields Into the WRFDA 4DVAR System to Improve Regional Rainfall Forecasting

Journal of Advances in Modeling Earth Systems, Volume 18, Issue 4, April 2026.
Abstract Accurate representation of atmospheric water vapor is crucial for improving numerical weather prediction, particularly over regions with complex topography and sparse observation networks. Although assimilation of Global Navigation Satellite System (GNSS)‐derived integrated products such as zenith total delay or precipitable water vapor can ...
Arash Tayfehrostami, Yazdan Amerian, Saeed Izanlou, Majid Azadi   +3 more
wiley   +1 more source

New Models of Zenith Tropospheric Delay for Chinese Mainland and Surrounding Areas Based on Convolutional Neural Network and Random Forest

IEEE Access
Accurate models of zenith tropospheric delay (ZTD) is crucial in meteorology as well as in navigation and positioning. In this study, we employ Convolutional Neural Network (CNN) and Random Forest (RF) models to establish six direct or compensation ...
Jiahao Zhang, Qin Liang, Yunqing Huang
doaj   +1 more source

Assessment of GNSS zenith tropospheric delay responses to atmospheric variables derived from ERA5 data over Nigeria

Satellite Navigation, 2023
Tropospheric delay is a major error caused by atmospheric refraction in Global Navigation Satellite System (GNSS) positioning. The study evaluates the potential of the European Centre for Medium-range Weather Forecast (ECMWF) Reanalysis 5 (ERA5 ...
Ifechukwu Ugochukwu Nzelibe, Herbert Tata, Timothy Oluwadare Idowu   +2 more
doaj   +1 more source

GPS zenith tropospheric delay (ZTD) variability in the Mediterranean

Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy, 2001
Abstract In the context of the MAGIC project (Meteorological Applications of GPS Integrated Column Water Vapor Measurements in the Western Mediterranean), zenith tropospheric delays (ZTD) are computed from Global Positioning System (GPS) signals at permanent sites in the western Mediterranean area continuously since November 1998.
Haase, J., Vedel, H., Ge, M., Calais, E.
openaire   +4 more sources

Thermally Stable, Low‐Resistance Cu Alloy Contacts for Mg3(Sb, Bi)2 Thermoelectric Materials by Two‐Step Contacting

Small Structures, Volume 7, Issue 3, March 2026.
Selection of suitable electrical contact is crucial for achieving low specific contact resistivity (ρc) at the electrode/thermoelectric (TE) material interface. Sustaining low ρc is far more critical than merely attaining a low value. Moreover, the conversion efficiency (η) and durability are often limited by unstable contact interfaces at various ...
Muhammad Fasih Aamir, Jayachandran Babu, Raju Chetty, Takao Mori   +3 more
wiley   +1 more source

RESEARCH ON ZENITH TROPOSPHERIC DELAY MODELING OF REGIONAL CORS NETWORK [PDF]

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2020
By calculating the zenith troposphere information from 11 reference stations of the CORS network in Guilin City, Guangxi Province in 2018 by GAMIT10.6 as the reference values, analyzing the relationship between the zenith troposphere and the elevation ...
Y. F. Yang, X. P. Chen, M. H. Yao, C. L. Zhou, C. M. Liao   +4 more
doaj   +1 more source

Impacts of Stochastic Modeling on GPS-derived ZTD Estimations

, 2004
GPS-derived ZTD (Zenith Tropospheric Delay) plays a key role in near real-time weather forecasting, especially in improving the precision of Numerical Weather Prediction (NWP) models. The ZTD is usually estimated using the first-order Gauss-Markov process with a fairly large correlation, and under the assumption that all the GPS measurements, carrier ...
Jin, S, Wang, J
openaire   +3 more sources

Capturing Extreme Water Vapor and Instability With High‐Resolution GNSS Monitoring

Atmospheric Science Letters, Volume 27, Issue 2, February 2026.
This study used data from a high‐resolution Global Navigation Satellite System network (< 10 km spacing), including private stations, to analyze water vapor structure during a heavy rainfall event in Japan. The network captured localized extreme precipitable water vapor (> 70 mm) and a moist absolutely unstable layer near the humid core.
Mikiko Fujita
wiley   +1 more source

A Selective State-Space-Model Based Model for Global Zenith Tropospheric Delay Prediction

Remote Sensing
The Zenith Tropospheric Delay (ZTD) is a significant atmospheric error affecting the accuracy of the Global Navigation Satellite System (GNSS). Accurate estimation of the ZTD is essential for enhancing GNSS positioning precision and plays a critical role
Cong Yang, Xu Lin, Zhengdao Yuan, Lunwei Zhao, Jie Zhao, Yashi Xu, Jun Zhao, Yakun Han   +7 more
doaj   +1 more source