The research on the characteristics of Arctic climate change under the background of future warming is of great significance. This research studies the spatiotemporal variability of Arctic 2m temperature in the 21st century under the SSP2-4.5 scenario based on the climate models with better simulation of Arctic climate change in the Coupled Model Intercomparison Project Phase 6 (CMIP6). The results show that: (1) The Eurasian part (EA) and the North America-Greenland part (GL) of the polar continent have different changing trends. The EA has significant warming trend before the middle of the 21st century, and then mainly shows the interdecadal oscillations; GL maintains a warming trend. The temperature of EA and GL fluctuates on annual and interdecadal (10-20a) scales, and there is also a quasi-periodic variation of 20-40a in GL. (2) The positive phase of the North Atlantic Oscillation in the previous winter will cause the North Atlantic to present a south-north "-, +, -" tripolar sea surface temperature anomaly (SSTA) in the next summer, and lead to a positive temperature anomaly in the EA by affecting the atmospheric circulation. (3) When the Atlantic Multidecadal Oscillation is positive, the geopotential height from North America to Greenland is high, and the GL warms. This effect is more important after the 2070s. The positive SSTA of the north of the North Pacific also contribute to the warming of the GL.