A new model for the estimation of the dry path delay affecting electromagnetic waves traversing the neutral atmosphere (troposphere and stratosphere) is presented. For instance, an accurate evaluation of this parameter is necessary to directly get the amount of water vapour in the atmosphere from measurements of radio signals total delay available from Global Navigation Satellite Systems (GNSS) observations. The new model is based on a modification of the conventional Saastamoinen model and it is still based on surface data. It has been experimentally developed by linear regression exploiting a large set of radiosonde observations (107168 for the training phase, 17654 for the test phase) covering all latitudes and seasons with the purpose to obtain a high accuracy in the zenith dry delay (ZDD) estimation process employing dependence on surface temperature and pressure. The testing procedure has shown good performances with respect to the ZDD computed from radiosondes profiles (zero error bias, error standard deviation 0.48 cm) and a simple and general applicability of the formulated model design over a global range of spatial and temporal scales.
Tropospheric dry delay for microwaves using a model based on surface measurements on a global scale
Bonafoni, Stefania;
2018
Abstract
A new model for the estimation of the dry path delay affecting electromagnetic waves traversing the neutral atmosphere (troposphere and stratosphere) is presented. For instance, an accurate evaluation of this parameter is necessary to directly get the amount of water vapour in the atmosphere from measurements of radio signals total delay available from Global Navigation Satellite Systems (GNSS) observations. The new model is based on a modification of the conventional Saastamoinen model and it is still based on surface data. It has been experimentally developed by linear regression exploiting a large set of radiosonde observations (107168 for the training phase, 17654 for the test phase) covering all latitudes and seasons with the purpose to obtain a high accuracy in the zenith dry delay (ZDD) estimation process employing dependence on surface temperature and pressure. The testing procedure has shown good performances with respect to the ZDD computed from radiosondes profiles (zero error bias, error standard deviation 0.48 cm) and a simple and general applicability of the formulated model design over a global range of spatial and temporal scales.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
