The Accuracy Analysis of GPT2w at the Antarctic Area

GPT2w (global pressure and temperature 2 wet) is one of the widely used empirical troposphere models, which is usually used to compute the tropospheric parameters, such as pressure, temperature, water vapor pressure etc. In order to analyze the model accuracy around the Antarctic Pole area, the actu...

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Bibliographic Details
Main Authors: KONG Jian, YAO Yibin, SHAN Lulu, WANG Zemin
Format: Article in Journal/Newspaper
Language:Chinese
Published: Surveying and Mapping Press 2018
Subjects:
Online Access:https://doi.org/10.11947/j.AGCS.2018.20170487
https://doaj.org/article/056d47ba35aa428bbb6c5d4c9d2c87c4
Description
Summary:GPT2w (global pressure and temperature 2 wet) is one of the widely used empirical troposphere models, which is usually used to compute the tropospheric parameters, such as pressure, temperature, water vapor pressure etc. In order to analyze the model accuracy around the Antarctic Pole area, the actual data from the radiosonde stations and the measured data during the Chinese 33th Antarctica Expedition are used to test the model parameter's accuracy on different height level. Based on the comparison with the data from the radiosonde stations and GPT2w, it is found that on ground level, the model accuracy at Antarctic Pole area is high, which is consistent with the accuracy at other areas; then by comparing the statistics in January and July, it is found that Bias and RMS showed seasonal characteristics; at the same time, it is found that there is a large error in the vertical direction of the model, which shows that as the height increases, the accuracy decreases and gradually stabilizes.Before the comparison with the measured data and GPT2w, the ECMWF(European Centre for Medium-range Weather Forecasts)data are used to confirm the reliability of the measured data, while the results showed that the two dataset consistent with each other. Meanwhile, by comparison, it is found that the GPT2w accuracy among a day is equal to monthly average accuracy on ground level, but the vertical accuracy decreases with the increase of height compared with the accuracy of the warm season, which shows that there is a certain impact on the accuracy of the model without considering the variation of the daily period. zenith tropospheric delay (ZTD) calculated by sounding data is used to analyze the accuracy of GPT2w. The result shows that the accuracy of GPT2w ZTD in the Antarctic is centimeter accuracy, which is equivalent to the accuracy of other areas in the world.