Abstract: The Arctic cryosphere has experienced substantial changes under global warming. Arctic sea ice has been steadily receding, with diminishing area,  thickness, and volume in recent decades. It is projected that the sea ice will vanish entirely during summers by mid-century. This decline in Arctic sea ice has profound impacts on ecosystems, atmospheric circulation, ocean currents, mid-latitude weather and climate, as well as socio-economic development. The study on the changes of Arctic sea ice and their impacts is vital for the Arctic’s sustainable development. Additionally, it also helps to enhance China's discourse power, and safeguard our interests in the Arctic.