The Norilsk Mining and Metallurgical Plant for the production of nickel, platinum and palladium is the main pollutant in the Arctic. The nature and degree of its impact on natural ecosystems over a long, since 1935, history of its work, varied along with changes in production volumes under different forms of ownership, and the response of ecosystems developed against the background of climate warming. Based on a review of studies carried out in the region, periods with different ratios of technogenic and natural factors in the dynamics of ecosystems are distinguished, which also differ in the methods of their study. In the second half of the 20th century, in the 1970s–1990s, an increase in sulfur dioxide emissions into the atmosphere led to the drying up of larch forests at a distance of up to 120 km southeast of the plant, recorded by aerial photography and forest pathological studies, as well as by a map of the ecosystems state, compiled by Landsat imagery and MSU field research. At the end of the 20th century, after the collapse of the USSR, an interruption in the operation of the plant, which passed from state to private ownership, led to a decrease in production rates and emissions into the atmosphere. This was combined with climate warming, which intensified in the Arctic regions. Complex expeditionary work of Siberian scientists in the first decades of the XXI century, including geochemical and dendrochronological studies, fixed the boundaries of zones of varying degrees of disturbance of ecosystems, but at the same time showed that along with the continuing degradation of vegetation, partial restoration of ecosystems is taking place. At the end of the second decade of the XXI century, Russian and American scientists, based on the processing of large volumes of remote sensing data, based on a multi-temporal analysis of vegetation indices, discovered the “greening” of low habitats in the Norilsk region as a result of secondary succession with a complex interaction of technogenic and natural, primarily climatic, factors.