Climate change is reshaping the terrestrial ecosystem patterns of the Northern Hemisphere, with ecological vulnerability being particularly pronounced in middle and high latitudes under the influence of Arctic amplification. However, a systematic quantification of the spatiotemporal evolution of ecological vulnerability across different ecosystem types and their dominant climate driving mechanisms remains lacking. Based on MODIS NDVI, CRU, and ERA5-Land climate reanalysis data from the 2001~2023 growing seasons, this study constructed an integrated sensitivity-adaptive capacity assessment framework to systematically evaluate the spatiotemporal dynamics of ecological vulnerability for three ecosystems north of 30°N: forest, other woody vegetation, and grassland. Structural equation modeling was used to identify the key climate driving mechanisms. The results indicate that: (1) Ecological vulnerability showed distinct spatial heterogeneity, with high-value areas (EV > 0.30) concentrated in high-latitude permafrost degradation zones and low-value areas (EV < 0.30) mainly distributed in temperate humid regions; (2) Temporally, the overall ecosystem vulnerability decreased during 2013~2023 compared to 2001~2012, with forests showing the most significant improvement and the highest stability, while grassland ecosystems exhibited the highest vulnerability with limited improvement; (3) The climate driving mechanisms differed significantly among ecosystems: air temperature was the dominant factor suppressing ecological vulnerability, with its effect strongest at high latitudes; increased surface solar radiation significantly exacerbated vulnerability in mid-latitude ecosystems; increased precipitation suppressed forest vulnerability but exacerbated grassland vulnerability in mid-latitude regions. This study reveals the differential responses of various ecosystems to climate change and their underlying driving mechanisms, emphasizing the necessity for differentiated ecological management strategies and providing a scientific basis for addressing future climate risks.