Programme: Scientific Research Fund

The existence of permafrost zones in temperate latitudes, and particularly in Bulgaria, is poorly known and insufficiently studied. It is assumed that permafrost in this regions occurs in the high mountain areas as isolated patches, unlike the extensive permafrost territories in subpolar regions. One of the indicators of permafrost presence is the occurrence of perennial snow patches, which can also be observed in Bulgarian mountains. Conducting investigations, and especially geophysical measurements aimed at proving the existence of permafrost zones and carrying out their subsequent monitoring, is challenging in mountainous terrain.The reason is that these sites are often located on steep and difficult-to-access slopes and at the base of rocky escarpments.
During the period 2019–2024,the project team carried out measurements in the Pirin Mountains and demonstrated the existence of a permafrost zone in Bulgaria. As a result, we were invited to participate in the COST proposal PermaCOST. PermaCOST aims to bring together European researchers, stakeholders, and practitioners working in the field of permafrost, with expertise in various measurement techniques and permafrost conditions, in order to establish coordinated and standardized monitoring of permafrost response to climate change.
In the present project, we will continue the monitoring of the permafrost zone in the Pirin Mountains using the geophysical methods as electrical resistivity tomography and ground-penetrating radar, which are standard techniques for this purpose. In addition, passive seismic measurements will be included for the first time. Although still not widely used in permafrost studies, this method has already been applied in several Arctic investigations together with other geophysical techniques.Its implementation in the Pirin Mountains is fully consistent with the objectives of WG1 of the COST Action, whose main task is to collect and evaluate different methods for permafrost investigations.