Arctic Is Likely to become Ice-Free by the End of This Century
The Arctic is warming at an alarming rate. Over the past few decades, parts of the Arctic have warmed nearly 2 degrees Fahrenheit. This melting of Arctic ice has caused the region to heat up more quickly than anywhere else on Earth. As a result, the region could become ice-free by the end of this century, according to data released in February by NASA and its partners. The consequences for humans will be wide-ranging and include more frequent droughts that lead to mass migrations. But from an environmental perspective, the change could also be good news because it could trigger a natural cycle that would return vast reserves of fresh water to northern lands.
What Causes Arctic Ice to Melt?
The most obvious cause of Arctic ice melting is the expansion of the human population, particularly in the cities. In the year 2000, an estimated 6.5 million people were living in the cities of the Arctic, up from only 0.5 million in 1970. To put this in perspective, people were living in the Arctic 19 times as much in 2000 as they were then. Additionally, this growth is expected to continue, both due to natural population increase and a growing dependence on fossil fuels. With little hope for substantial declines in carbon emissions, the only other option for reducing carbon emissions is to adapt to the change.
How Rapid is the Melting of Arctic Ice?
The rate of Arctic ice melting is increasing, largely as a result of human activities. The rapidity of this change is determined by a number of factors, including the amount of human-made heat being released into the atmosphere, the amount of freshwater being released to the ocean, and the amount of solar energy reaching the Earth’s surface. The average annual rate of Arctic ice change is estimated at 0.15 to 0.25 degrees F per decade. This rate of change is small compared to the rates of change seen in other regions of the world.
How Does the Melting of Arctic Ice Impact Humans?
The Arctic has been slowly melting for thousands of years. The average rate of change has been small because most of the water in the region is covered by two to five feet of ice most years. However, during periods of climate change, the average rate of ice melting can be substantial. Increased levels of carbon dioxide in the atmosphere, for example, are believed to be the cause of the Last Glacial Maximum, which occurred between 20,000 and 10,000 years ago. This period of drastically reduced ice cover is also known as the cold snap. With the return of a warm climate, the glaciers in the Arctic are being rapidly melted.
How Does the Ending of Arctic Ice Change Climate?
The Arctic ice cap is the largest single source of greenhouse gas emissions, accounting for about one-quarter of all greenhouse gas emissions from human activities. With the rapid disappearance of the Arctic ice cap, human-induced climate change is likely to accelerate, with atmospheric CO2 levels increasing and global warming potential reaching 1.5 in 20 years.
Impact on Greenland
The Greenland ice sheet is the largest ice sheet on earth, currently holding about two-thirds of the world’s ice and causing concern about the future of sea level rise. The ice sheet is a source of water for much of the world and accounts for about five percent of global freshwater withdrawal. It also absorbs around one-fifth of all the solar energy Earth receives. The melt rate of the Greenland ice sheet is estimated to be between one and three times greater than the rate at which the ice is being produced. If this difference became negative, the ice sheet would lose mass and rise in temperature, causing the sea level to rise by about one-tenth of a meter.