The Arctic Ocean may experience an earlier than expected "ice free summer" gas | greenhouse | Arctic Ocean
The latest assessment report of the United Nations Intergovernmental Panel on Climate Change suggests that the Arctic Ocean is expected to experience a summer ice free period 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 earlier than the 1930s, and therefore 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 between 2030 and 2050 at the earliest. In high emission scenarios, 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 area covered by ice in the Arctic Ocean is less than 7%, or 1 million square kilometers, it can be considered "ice free".
Generally speaking, the amount of ice in the Arctic Ocean decreases after the start of summer each year and reaches its minimum value in mid September. In recent years, the Arctic summer sea ice area has rapidly shrunk, which is one of the most obvious signals of human activities leading to climate change. Most experts believe that the Arctic Ocean will experience a lack of ice in the late summer of a certain year in this century, but there is controversy over the specific year.
The latest assessment report of the United Nations Intergovernmental Panel on Climate Change, the sixth assessment report, predicts that in the context of maintaining moderate or high greenhouse gas emissions, the Arctic sea ice area is expected to experience at least one ice free situation around the middle of this century, and ice free will become the norm from September 2081 to 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 emphasizes the profound impact of greenhouse gas emissions on the Arctic region, highlighting the importance of early planning and adaptation to seasonal ice free conditions in the near future.
One of the authors of the paper, Professor Dirk Noz from the Institute of Oceanography at the University of Hamburg in Germany, told Agence France Presse: "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."
According to researchers cited by Agence France Presse, melting Arctic sea ice will not cause sea level rise. However, warming in the Arctic region may accelerate the melting of Greenland's ice sheet. These ice sheets are composed of freshwater ice trapped on land, and once completely melted, the amount of water is enough to raise global sea levels 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 affecting human society and the global ecosystem.
Data shows that compared to the late 19th century, the average temperature in the Arctic and Antarctic regions 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.
