News

IGiG scientific seminar - Dr. Guergana Guerova

17-01-2025

IGiG is pleased to invite to a scientific seminar, which will take place on February 18, 2025 (Tuesday) at 9:00 AM in the Room 100G (institute library), Grunwaldzka Street 53, Wrocław (Building C1). Dr. Guergana Guerova from the University of Sofia will present a lecture "GNSS Storm Nowcasting Demonstrator".



Abstract:
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. In this presentation the added value of sub-hourly real-time GNSS tropospheric products for the nowcasting of convective storms in Bulgaria will be discussed. 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–September 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 24–30 August 2021. Real-time tropospheric products and classification functions are integrated and updated in real-time on a publicly accessible geoportal.

Bio:
Guergana Guerova is an associate professor at the Department of Meteorology and Geophysics of the Sofia University, Sofia, Bulgaria. She received a MSc degree in meteorology from Sofia University and PhD in applied physics from University of Bern. She is Marie Curie IRG Fellow (2011-2014), vice chair of COST Action ES1206 GNSS4SWEC (2013-2017), team leader of Interreg BERTISS project (2017-2019) and project leader of ESA PECS “GNSS nowcasting demonstrators” (2021-2024). Her research interest cover monitoring short and long-term variation of GNSS derived water vapour in particular for studying fog, intense precipitation, hail storm and heat waves. She is recognised internationally in the field of GNSS meteorology and numerical modelling of the atmosphere, having published 37 papers, attracting over 330 citations. Dr. Guerova currently supervises 3 PhD candidates and have previously advised 7 PhD and 25 MSc/BSc students to successful completion. At the Sofia University she teaches courses at undergraduate (Introduction in Meteorology part 1, Synoptic Analysis) and graduate (Satellite Imagery Interpretation) level.

http://suada.phys.uni-sofia.bg/