According to the latest assessment report of the Intergovernmental Panel on Climate Change, the Arctic Ocean is expected to be ice free in summer as early as around the middle of this century. However, an international research team published a paper in the British journal Nature Communications on the 6th, suggesting that the "ice free summer" may have appeared as early as the 1930s, thus reminding relevant parties to prepare early. This team, composed of researchers from South Korea, Canada, and Germany, used satellite data to study the sea ice cover in the Arctic region from 1979 to 2019. Based on this, a model was established to predict the trend of sea ice area changes under different levels of greenhouse gas emissions. The results show that regardless of the level of greenhouse gas emissions, the Arctic Ocean will experience the first September without sea ice as early as 2030 to 2050. In the context of high emissions, it is expected that the Arctic region will have no sea ice by early summer by the end of this century. The scientific community generally believes that if the Arctic Ocean is less than 7% covered by ice, or 1 million square kilometers, it can be considered "ice free". Generally speaking, the amount of ice in the Arctic Ocean decreases after the beginning of summer each year and reaches its minimum in mid September. In recent years, the Arctic summer sea ice area has rapidly decreased, which is one of the most obvious signals of human activities leading to climate change. Most experts believe that the Arctic Ocean will experience an ice free period in the late summer of this century, but there is controversy over the specific year. The latest and sixth assessment report of the United Nations Intergovernmental Panel on Climate Change predicted that under the scenario of moderate or high greenhouse gas emissions, the Arctic sea ice area is expected to be ice free at least once around the middle of this century, and ice free will become the norm in September between 2081 and 2100; If greenhouse gas emissions can remain low, the Arctic region will not experience an "ice free summer" this century. Researchers believe that this latest study highlights the profound impact of greenhouse gas emissions on the Arctic region, demonstrating the importance of early planning and adaptation for seasonal ice free conditions in the near future. Dirk Noz, one of the authors of the paper and professor of the Institute of Oceanography of the University of Hamburg in Germany, told AFP: "It is too late to protect the Arctic summer sea ice as a landscape and habitat. This will be the first major component of our climate system lost due to greenhouse gas emissions." AFP quoted researchers as saying that the melting of Arctic sea ice will not lead to sea level rise. However, warming in the Arctic region may accelerate the melting of the Greenland ice sheet. These ice sheets are composed of fresh water ice trapped on the land. Once completely melted, the amount of water is enough to raise the Eustatic sea level by 6 meters. In addition, one of the important functions of sea ice is to reflect solar radiation back into space. As sea ice melts, the Earth will absorb more solar energy, accelerating the warming of the Arctic and thus' affecting human society and global ecosystems'. Data shows that compared with the late 19th century, the average temperature in the Arctic and Antarctic has risen by 3 degrees Celsius, nearly three times the global average. In 2012, the sea ice area of the Arctic reached a record low of only 3.4 million square kilometers, and in 2020 and 2019, the sea ice area was also at a historical low