Advances in Atmospheric Sciences

, Volume 22, Issue 5, pp 759–764

Retrieval of water vapor profiles with radio occultation measurements using an artificial neural network

Article

Abstract

A new method applying an artificial neural network (ANN) to retrieve water vapor profiles in the troposphere is presented. In this paper, a fully-connected, three-layer network based on the back-propagation algorithm is constructed. Month, latitude, altitude and bending angle are chosen as the input vectors and water vapor pressure as the output vector. There are 130 groups of occultation measurements from June to November 2002 in the dataset. Seventy pairs of bending angles and water vapor pressure profiles are used to train the ANN, and the sixty remaining pairs of profiles are applied to the validation of the retrieval. By comparing the retrieved profiles with the corresponding ones from the Information System and Data Center of the Challenging Mini-Satellite Payload for Geoscientific Research and Application (CHAMP-ISDC), it can be concluded that the ANN is relatively convenient and accurate. Its results can be provided as the first guess for the iterative methods or the non-linear optimal estimation inverse method.

Key words

radio occultation water vapor artificial neural network back-propagation 

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Copyright information

© Advances in Atmospheric Sciences 2003

Authors and Affiliations

  1. 1.Laboratory for Middle Atmosphere and Global Environment Observation, Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing

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