30.10.2026 09:12
Analysis conducted using satellite images revealed that the surface area of Lake Van has shrunk by approximately 31 square kilometers since 1990. While the lake lost only 4 square kilometers between 1990 and 2015, it receded by 27 square kilometers in the 10 years between 2015 and 2025. According to cartographer Prof. Dr. Murat Yakar, approximately 87 percent of the total loss occurred in the last 10 years.
BITLIS (IHA) – Prof. Dr. Murat Yakar, a map scientist and member of the Anatolian Underwater Research and Sports Association (ASAD), stated that the shoreline and water surface areas of Lake Van in 1990, 2015 and 2025 were compared using satellite images, and said, “The analysis results show that the lake’s surface area has decreased by approximately 31 square kilometers over the last 35 years, and most of this decrease occurred in the last 10 years.”
Within the scope of the “My Future Is Hidden in Lake Van: Underwater Technologies and Career Route for Young People Aged 14-18” project, prepared by the Anatolian Underwater Research and Sports Association (ASAD) and supported by the General Directorate of Civil Society Relations of the Ministry of Interior, the changes in Lake Van’s shoreline and water surface area over 35 years were examined. In the study carried out by ASAD member and map scientist Prof. Dr. Murat Yakar, satellite images from 1990, 2015 and 2025 were compared and the lake’s surface areas in different periods were calculated. The analyses revealed that the shrinkage of Lake Van has accelerated especially in the last 10 years.
35-YEAR COMPARISON WITH SATELLITE IMAGES
Prof. Dr. Murat Yakar stated that they carried out remote sensing and Geographic Information Systems (GIS)-based analyses to determine the change in Lake Van’s shoreline. In the study, using images obtained from the Landsat 4-5 and Landsat 8-9 satellite systems, the Normalized Difference Water Index (NDWI), which is widely used to identify water surfaces, was calculated, and water and land areas were separated from each other using the threshold value method. The obtained data were processed in a GIS environment and the lake’s surface areas in different years were determined.
87 PERCENT OF THE LOSS IN THE LAST 10 YEARS
According to the analysis results, Lake Van’s surface area was calculated as approximately 3,577 square kilometers in 1990. This area declined to 3,573 square kilometers in 2015 and to 3,546 square kilometers in 2025. Accordingly, while there was a decrease of approximately 4 square kilometers in the 25-year period between 1990 and 2015, a loss of 27 square kilometers was identified in the 10-year period between 2015 and 2025 alone. It was noteworthy that approximately 87 percent of the total 31 square kilometers of surface area loss calculated over the 35-year period examined occurred in the last 10 years.
Within the scope of the study, the shoreline for 1990, 2015 and 2025 was shown on a comparative map. Thus, coastal changes in different parts of Lake Van became spatially examinable. Prof. Dr. Murat Yakar, noting that long-term changes in lakes can be monitored by using satellite images and GIS technologies together, stated that such studies provide important data for identifying changes in water resources and for future research. Yakar said, “Using satellite images, the shoreline and water surface areas of Lake Van in 1990, 2015 and 2025 were compared. The analysis results revealed that there has been a decrease of approximately 31 square kilometers in the lake’s surface area over the last 35 years, and that most of this decrease occurred in the last 10 years. Remote sensing and Geographic Information Systems (GIS)-based analyses carried out to determine the coastal change of Lake Van over the last 35 years showed that there has been a remarkable decrease in the lake’s water surface area, especially in the last 10 years. In the study, using Landsat satellite images from 1990, 2015 and 2025, the shoreline of Lake Van in different periods was determined. On the images obtained from the Landsat 4-5 and Landsat 8-9 satellite systems, the Normalized Difference Water Index (NDWI), widely used to identify water surfaces, was calculated. Then, water and land areas were separated from each other using the threshold value method applied. The identified water areas were converted into polygon data in a GIS environment and the lake’s surface areas in different years were calculated.”
Prof. Dr. Murat Yakar, who said, “According to the analysis results, while Lake Van’s water surface area was determined as approximately 3,577 square kilometers in 1990, this value declined to 3,573 square kilometers in 2015 and to 3,546 square kilometers in 2025,” continued as follows:
“While a decrease of approximately 4 square kilometers was identified in the lake’s surface area during the 25-year period between 1990 and 2015, it was noteworthy that this decrease reached 27 square kilometers in the 10-year period between 2015 and 2025 alone. Thus, it was determined that approximately 87 percent of the total 31 square kilometers of surface area loss calculated over the 35-year period examined occurred in the last 10-year period. These findings indicate that the decrease in Lake Van’s water surface area has become particularly evident in the recent period. On the comparative map prepared within the scope of the study, the shoreline for 1990, 2015 and 2025 was shown on the same geographical base. Thus, coastal changes in different parts of the lake were made spatially examinable. The use of satellite images and GIS technologies together enables the monitoring of long-term changes in lakes with large water surfaces. In particular, comparing satellite data from different years is important for identifying changes in water resources and for providing a basis for detailed future research. The surface area changes identified in Lake Van once again demonstrate the importance of regularly monitoring lakes and other water resources with satellite technologies. Changes in lake surface area can be affected by many factors such as precipitation, evaporation, temperature and hydrological conditions. However, in order to reveal the causes of the identified changes, comprehensive analyses supported by long-term climate data, lake water level measurements and other hydrological data are needed. The results obtained from satellite images from three different years show that there has been a significant decrease in Lake Van’s water surface area, especially in the 2015-2025 period, while drawing attention to the importance of regular and scientific monitoring studies for the sustainable management of water resources in the region,” he said.
CALL FOR MONITORING FOR LAKE VAN
ASAD Bitlis Representative Assoc. Prof. Dr. Cihan Önen, on the other hand, stated that within the scope of the “My Future Is Hidden in Lake Van” project, which they carried out with the support of the General Directorate of Civil Society Relations of the Ministry of Interior, they had Lake Van’s surface area measured. Emphasizing that changes in the lake’s surface area and shoreline should be regularly monitored with scientific data, Önen stated that protecting Lake Van is an important responsibility in terms of transferring the shared natural heritage to future generations.