Tropospheric modeling: study and analysis of different models

Abstract

In the past few years is increasing the necessity of realizing high accuracy positioning. In this sense, the spatial technologies have being widely used. The GNSS (Global Navigation Satellite Systems) has revolutionized the geodetic positioning activities. But, in order to get the intended accuracy, is indispensable to realize the atmospheric modeling (ionosphere and troposphere) accordingly. Related to troposphere, there are the empirical models (for example Saastamoinen and Hopfield). But when accuracy results are desired, maybe these models are not appropriated to the Brazilian reality. In order to minimize this limitation arise the NWP (Numerical Weather Prediction) models. In Brazil the CPTEC/INPE (Weather Prediction and Climate Studies of Center of the National Institute for Space Research) makes available values of tropospheric delay for South America and oceans, accessed online. In this research, the main goal is to study, implement and analyze different tropospheric models in diverse regions of the country. A very interesting topic considering the tropospheric peculiarities in the country is that it has dry and wet regions, due mainly to Amazonic forest. (AU)