AMT Atmospheric Measurement Techniques AMT Atmos. Meas. Tech. 1867-8548 Copernicus Publications Göttingen, Germany 10.5194/amt-7-2683-2014 The Sofia University Atmospheric Data Archive (SUADA) Guerova G. https://orcid.org/0000-0001-5638-3387 1 Simeonov T. https://orcid.org/0000-0001-9007-7084 1 Yordanova N. 1 Sofia University, Faculty of Physics, Department of Meteorology and Geophysics, 5 James Bourchier Blvd., 1164 Sofia, Bulgaria 21 08 2014 7 8 2683 2694 Copyright: © 2014 G. Guerova et al. 2014 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://amt.copernicus.org/articles/7/2683/2014/amt-7-2683-2014.html The full text article is available as a PDF file from https://amt.copernicus.org/articles/7/2683/2014/amt-7-2683-2014.pdf

Atmospheric sounding using the Global Navigation Satellite Systems (GNSS) is a well-established research field in Europe. At present, GNSS data from 1800 stations are available for model validation and assimilation in state-of-the-art models used for operational numerical weather prediction centres in Europe. Advances in GNSS data processing make it possible also to use the GNSS data for climatic trend analysis, an emerging new application. In Bulgaria and southeastern Europe, the use of GNSS for atmospheric sounding is currently under development. <br><br> As a first step, the Sofia University Atmospheric Data Archive (SUADA) is developed. SUADA is a user-friendly database, and includes GNSS tropospheric products like zenith total delay (ZTD) and derivatives like vertically integrated water vapour (IWV), as well as observations from radiosonde (RS) and surface atmospheric data. Archived in SUADA are (1) GNSS tropospheric products (over 12 000 000 individual observations) and derivatives (over 55 000) from five GNSS processing strategies and 37 stations for the period 1997–2013, with temporal resolutions from 5 min to 6 h, and (2) radiosonde IWV data (over 6000 observations) for station Sofia (1999–2012). <br><br> Presented are two applications of the SUADA data for the study of long- and short-term variations of IWV over Bulgaria during the 2007 heatwave and intense precipitation events in 2012.

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