Arctic sea ice extent fell to its lowest level since satellite observations began in 1979, marking one of the most alarming signals in global climate monitoring in 2025, according to a new report released by the China Meteorological Administration.

The State of Polar Climate 2025 report, released Wednesday, highlights intensifying warming trends, persistently low sea ice levels and increasingly abnormal extreme events in both polar regions. It is the fourth consecutive year China has issued the annual assessment.

The report shows that the Arctic's annual average sea ice extent reached a record low, while its yearly maximum extent also hit the lowest level in 47 years.

"It is one of the most alarming signals in global climate monitoring in 2025," said Zeng Qin, director of the administration's department of science and technology.

"The polar regions are both sensitive areas and amplifiers of global climate change," Zeng said.

Rising temperatures, melting ice and ozone shifts can influence atmospheric and ocean circulation, radiation balance and sea levels worldwide, he added.

According to the report, the Arctic continued to warm last year, with an annual average temperature of minus 6.4 C, 1.14 degrees above the long-term average. Warming was observed across all seasons, particularly in winter and autumn, and the Barents Sea region was identified as a major hot spot.

Antarctica also recorded above-average temperatures overall. The annual average temperature stood at minus 31.29 C, 0.55 C above normal.

Several monitoring stations near the Antarctic Peninsula, including Britain's Rothera Research Station, recorded their highest temperatures on record.

Sea ice in Antarctica also remained at historically low levels. The continent's annual average sea ice extent was among the three lowest recorded since 1979, the report said.

The study also highlighted diverging trends in ozone levels. The Antarctic ozone hole showed signs of recovery, with its maximum daily extent ranking as the fifth smallest on record and closing about three weeks earlier than usual.

In contrast, ozone levels in the Arctic dropped sharply in March last year, reversing trends seen in the previous year.

Concentrations of major greenhouse gases, including carbon dioxide and methane, continued to rise in both polar regions, further contributing to warming.

Extreme weather events in the polar regions became more pronounced, the report found.

In October, rare rainfall was recorded at China's Zhongshan National Atmospheric Background Station in Antarctica, underscoring the increasing abnormality of polar weather.

China has expanded its polar observation network in recent years, relying on research stations in Antarctica and the Arctic to build a system capable of operating in ultralow temperatures and covering key high-latitude regions, the administration said.