Reduction of glaciers in the Orulgan Range (Verkhoyansk Range) from 1951 to 2023

New data on glaciation of the Orulgan Range in 2013, 2018 and 2023 are presented. By analyzing multi-temporal satellite imagery and historical data, changes in glacier area were estimated from the mid-20th century through 2013, 2018, and 2023, and for the periods 2013–2018, 2018–2023, and 2013-2023. In 2023, the glaciation of the Orulgan Ridge consisted of 58 glaciers with a total area of 7.47±0.85 km². Among the morphological types, corrie glaciers and corrie-valley glaciers predominate. The largest areas are occupied by transfluent-valley and corrie-valley glaciers. The main part (71.8%) of the total area of glaciation in the region is concentrated in the altitudinal range of 1700–2000 m. From the middle of the 20th century to 2023, the area of glaciers registered in the USSR Glacier Inventory and identified in the Russian Glacier Catalog decreased from 16.41 to 7.47±0.85 km², i.e. by 8.94 km² (54.5%). Of these, 5.90 km² were lost from 1951–1967 to 2013, 1.14 km² between 2013–2018, and 1.90 km² between 2018–2023. By 2023, small glaciers with area less than 0.1 km² (84.7%) were the most reduced and largest glacier with area more than 2 km² (12.9%) was the least reduced. The small glaciers of the western aspect decreased most significantly (91.7%). We found a significant increase in the average rate of glacier area reduction in the last 10 years compared to the period from the mid-20th century to 2013: 0.61%/year from 1951–1967 to 2013 to 2.17%/year in 2013–2018, and 4.06%/year in 2018–2023. These changes occurred at the background of a stable positive trend of mean annual air temperature, the magnitude of which is especially large, with acceleration of this process in the last decade.