{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T23:29:35Z","timestamp":1773358175225,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,8,4]],"date-time":"2022-08-04T00:00:00Z","timestamp":1659571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ESA Plan for European Cooperating States (PECS) Programme","award":["4000134003\/21\/NL\/CBi"],"award-info":[{"award-number":["4000134003\/21\/NL\/CBi"]}]},{"name":"ESA Plan for European Cooperating States (PECS) Programme","award":["HPC 1-221\/03.12.2018 (SU-NIS-3318)"],"award-info":[{"award-number":["HPC 1-221\/03.12.2018 (SU-NIS-3318)"]}]},{"name":"National Road-map for Research Infrastructures","award":["4000134003\/21\/NL\/CBi"],"award-info":[{"award-number":["4000134003\/21\/NL\/CBi"]}]},{"name":"National Road-map for Research Infrastructures","award":["HPC 1-221\/03.12.2018 (SU-NIS-3318)"],"award-info":[{"award-number":["HPC 1-221\/03.12.2018 (SU-NIS-3318)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Global Navigation Satellite System (GNSS) is an established atmospheric monitoring technique delivering water vapour data in near-real time with a latency of 90 min for operational Numerical Weather Prediction in Europe within the GNSS water vapour service (E-GVAP). The advancement of GNSS processing made the quality of real-time GNSS tropospheric products comparable to near-real-time solutions. In addition, they can be provided with a temporal resolution of 5 min and latency of 10 min, suitable for severe weather nowcasting. This paper exploits the added value of sub-hourly real-time GNSS tropospheric products for the nowcasting of convective storms in Bulgaria. A convective Storm Demonstrator (Storm Demo) is build using real-time GNSS tropospheric products and Instability Indices to derive site-specific threshold values in support of public weather and hail suppression services. The Storm Demo targets the development of service featuring GNSS products for two regions with hail suppression operations in Bulgaria, where thunderstorms and hail events occur between May and September, with a peak in July. The Storm Demo real-time Precise Point Positioning processing is conducted with the G-Nut software with a temporal resolution of 15 min for 12 ground-based GNSS stations in Bulgaria. Real-time data evaluation is done using reprocessed products and the achieved precision is below 9 mm, which is within the nowcasting requirements of the World Meteorologic Organisation. For the period May\u2013September 2021, the seasonal classification function for thunderstorm nowcasting is computed and evaluated. The probability of thunderstorm detection is 83%, with a false alarm ration of 38%. The added value of the high temporal resolution of the GNSS tropospheric gradients is investigated for a storm case on 24\u201330 August 2021. Real-time tropospheric products and classification functions are integrated and updated in real-time on a publicly accessible geoportal.<\/jats:p>","DOI":"10.3390\/rs14153746","type":"journal-article","created":{"date-parts":[[2022,8,5]],"date-time":"2022-08-05T02:12:39Z","timestamp":1659665559000},"page":"3746","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["GNSS Storm Nowcasting Demonstrator for Bulgaria"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5638-3387","authenticated-orcid":false,"given":"Guergana","family":"Guerova","sequence":"first","affiliation":[{"name":"Department Meteorology and Geophysics, Physics Faculty, Sofia University \u201cSt. Kliment Ohridski\u201d, 1164 Sofia, Bulgaria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6668-6207","authenticated-orcid":false,"given":"Jan","family":"Dou\u0161a","sequence":"additional","affiliation":[{"name":"Research Institute of Geodesy, Topography and Cartography, 25066 Zdiby, Czech Republic"},{"name":"G-Nut Software, s.r.o., 25166 Senohraby, Czech Republic"}]},{"given":"Tsvetelina","family":"Dimitrova","sequence":"additional","affiliation":[{"name":"Hail Suppression Agency, 1606 Sofia, Bulgaria"}]},{"given":"Anastasiya","family":"Stoycheva","sequence":"additional","affiliation":[{"name":"National Institute of Meteorology and Hydrology, 1784 Sofia, Bulgaria"}]},{"given":"Pavel","family":"V\u00e1clavovic","sequence":"additional","affiliation":[{"name":"Research Institute of Geodesy, Topography and Cartography, 25066 Zdiby, Czech Republic"},{"name":"G-Nut Software, s.r.o., 25166 Senohraby, Czech Republic"}]},{"given":"Nikolay","family":"Penov","sequence":"additional","affiliation":[{"name":"Department Meteorology and Geophysics, Physics Faculty, Sofia University \u201cSt. Kliment Ohridski\u201d, 1164 Sofia, Bulgaria"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,4]]},"reference":[{"key":"ref_1","unstructured":"WMO (2017). Guidelines for Nowcasting Techniques, World Meteorological Organization. Technical Report."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5005","DOI":"10.1029\/96JB03860","article-title":"Precise point positioning for the efficient and robust analysis of GPS data from large networks","volume":"102","author":"Zumberge","year":"1997","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Teunissen, P.J. (2017). Carrier phase integer ambiguity resolution. Springer Handbook of Global Navigation Satellite Systems, Springer.","DOI":"10.1007\/978-3-319-42928-1"},{"key":"ref_4","first-page":"52","article-title":"Innovation: Comming Soon: The International GNSS Real-Time Service","volume":"23","author":"Caissy","year":"2012","journal-title":"GPS World"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Dou\u0161a, J., V\u00e1clavovic, P., Zhao, L., and Ka\u010dma\u0159\u00edk, M. (2018). New Adaptable All-in-One Strategy for Estimating Advanced Tropospheric Parameters and Using Real-Time Orbits and Clocks. Remote Sens., 10.","DOI":"10.3390\/rs10020232"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2989","DOI":"10.5194\/amt-9-2989-2016","article-title":"Benchmark campaign and case study episode in central Europe for development and assessment of advanced GNSS tropospheric models and products","volume":"9","author":"Dick","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_7","first-page":"431","article-title":"G-Nut software library - state of development and first results","volume":"10","year":"2013","journal-title":"Acta Geodynynamica Geomater."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"453","DOI":"10.1007\/s10291-012-0291-7","article-title":"Estimation and evaluation of hourly updated global GPS Zenith Total Delays over ten months","volume":"17","author":"Bennitt","year":"2013","journal-title":"GPS Solut."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"177","DOI":"10.28974\/idojaras.2018.2.5","article-title":"Severe convective supercell outbreak over western Bulgaria on July 8, 2014","volume":"122","author":"Bocheva","year":"2018","journal-title":"Idoj\u00e1r\u00e1s"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Guerova, G., Dimitrova, T., and Georgiev, S. (2019). Thunderstorm Classification Functions Based on Instability Indices and GNSS IWV for the Sofia Plain. Remote Sens., 11.","DOI":"10.3390\/rs11242988"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"5385","DOI":"10.5194\/amt-9-5385-2016","article-title":"Review of the state of the art and future prospects of the ground-based GNSS meteorology in Europe","volume":"9","author":"Guerova","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_12","first-page":"1","article-title":"Sensitivity of GNSS tropospheric gradients to processing options","volume":"2018","author":"Zus","year":"2018","journal-title":"Ann. Geophys. Discuss."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2183","DOI":"10.5194\/amt-10-2183-2017","article-title":"Inter-technique validation of tropospheric slant total delays","volume":"10","author":"Dick","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1627","DOI":"10.1016\/j.asr.2015.07.020","article-title":"Backward smoothing for precise GNSS applications","volume":"56","year":"2015","journal-title":"Adv. Space Res."},{"key":"ref_15","first-page":"247","article-title":"Atmospheric Correction for the Troposphere and Stratosphere in Radio Ranging of Satellites","volume":"15","author":"Saastamoinen","year":"1972","journal-title":"Geophys. Monogr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"679","DOI":"10.1007\/s00190-007-0135-3","article-title":"Short note: A global model of pressure and temperature for geodetic applications","volume":"81","author":"Boehm","year":"2007","journal-title":"J. Geod."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1029\/2005GL025546","article-title":"Global Mapping Function (GMF): A new empirical mapping function based on numerical weather model data","volume":"33","author":"Boehm","year":"2006","journal-title":"Geophys. Res. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"20489","DOI":"10.1029\/97JB01739","article-title":"Effects of atmospheric azimuthal asymmetry on the analysis of space geodetic data","volume":"102","author":"Chen","year":"1997","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_19","unstructured":"Petite, G., and Luzum, B. (2010). IERS Conventions, Verlag des Bundesamts f\u00fcr Kartographie und Geod\u00e4sie. IERS Technical Notes."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"394","DOI":"10.1007\/s10236-006-0086-x","article-title":"Modelling the global ocean tides: Modern insights from FES2004","volume":"56","author":"Lyard","year":"2006","journal-title":"Ocean. Dyn."},{"key":"ref_21","unstructured":"Skamarock, W.C., Klemp, J., Dudhia, J., Gill, D.O., Barker, D.M., Duda, M.G., Huang, X.Y., Wang, W., and Powers, J. (2008). A Description of the Advanced Research WRF Version 3, NCAR. Available online: https:\/\/opensky.ucar.edu\/islandora\/object\/technotes:500."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2844","DOI":"10.1016\/j.asr.2020.07.005","article-title":"BalkanMed real time severe weather service: Progress and prospects in Bulgaria","volume":"66","author":"Guerova","year":"2020","journal-title":"Adv. Space Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2683","DOI":"10.5194\/amt-7-2683-2014","article-title":"The Sofia University Atmospheric Data Archive (SUADA)","volume":"7","author":"Guerova","year":"2014","journal-title":"Atmos. Meas. Tech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1593","DOI":"10.1029\/RS020i006p01593","article-title":"Geodesy by radio interferometry: Effects of atmospheric modeling errors on estimates of baseline length","volume":"20","author":"Davis","year":"1985","journal-title":"Radio Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"15787","DOI":"10.1029\/92JD01517","article-title":"GPS Meteorology: Remote Sensing of Atmospheric Water Vapour Using the Global Positioning System","volume":"97","author":"Bevis","year":"1992","journal-title":"J. Geophys. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"803","DOI":"10.1029\/RS009i010p00803","article-title":"An improved equation for the radio refractive index of air","volume":"9","author":"Thayer","year":"1974","journal-title":"Radio Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3627","DOI":"10.1029\/JZ067i009p03627","article-title":"The U.S. Standard Atmosphere, 1962","volume":"67","author":"Sissenwine","year":"1962","journal-title":"J. Geophys. Res."},{"key":"ref_28","unstructured":"NIMH (2021). Monthly Hydrometeorological Bulletin, NIMH. Technical Report."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2605","DOI":"10.5194\/nhess-15-2605-2015","article-title":"On the inclusion of GPS precipitable water vapour in the nowcasting of rainfall","volume":"15","author":"Benevides","year":"2015","journal-title":"Nat. Hazards Earth Syst. Sci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2536","DOI":"10.3390\/rs12162536","article-title":"GNSS-based machine learning storm nowcasting","volume":"12","author":"Smolak","year":"2020","journal-title":"Remote Sens."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/15\/3746\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:04:20Z","timestamp":1760141060000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/15\/3746"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,8,4]]},"references-count":30,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2022,8]]}},"alternative-id":["rs14153746"],"URL":"https:\/\/doi.org\/10.3390\/rs14153746","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,8,4]]}}}