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Arctic surface temperature has increased at approximately twice the global rate over the past few decades and is also projected to warm most in the 21st century. The mechanism of Arctic vegetation response to this warming remains largely uncertain. Here, we analyse variations in the seasonal profiles of MODIS Leaf Area Index (LAI) and ERA-interim cumulative near-surface air temperature (SAT∑) over the northern Russia north of 60°N for 2000-2019. According to our study broad temporal interval (seasonal) trends cannot fully represent complex interannual variations of the whole LAI profile over the growing season. We find that narrow temporal interval (weekly) LAI trends form an inverted S-shape over the course of the growing season with enhanced green-up and senescence, but balanced during the growing season peak. Spatial patterns of weekly LAI trends are strongly correlated with weekly SAT∑ trends during the green-up, while causes of the browning trends during senescence remain unclear.Geographically the area with the statistically significant temperature-driven greening LAI trends is restricted by a large patch carrying spring-time positive SAT∑trends, which includes North Siberian Lowland, Taimyr, Yamal and adjacent territories.The strength, duration and timing of the changes depend on vegetation type: enhanced green-up is most pronounced in tundra, while enhanced senescence is pronounced in forests. Continued warming will likely increase the capacity both of the environment (i.e. permafrost thawing) and vegetation (i.e. appearance of more productive woody species), and transform LAI seasonal shifts to change of LAI seasonal amplitude. Continued release of climatic constrains will likely increase the capacity both of the environment (i.e. permafrost thawing) and vegetation i.e. appearance of more productive woody species), and transform LAI seasonal shifts to change of LAI seasonal amplitude).