Tipping Points Identified for Melting of Greenland Ice Sheet
A new study has identified two tipping points for the melting of the Greenland ice sheet. The southern portion will melt if 1000 gigatons of carbon are released into the atmosphere, while a loss of nearly the entire ice sheet will occur at 2500 gigatons of carbon emissions. The world has already emitted around 500 gigatons of carbon, which means that we are halfway towards the first tipping point.
The study warns that the first tipping point is not far from today’s climate conditions and once crossed, there is no going back. The Greenland ice sheet is already melting, and between 2003 and 2016, it lost around 255 gigatons of ice each year, mainly in the southern part.
Impacts of Melting Greenland Ice Sheet on Sea Level Rise
The complete melting of the Greenland ice sheet could cause global sea level to rise by about seven meters. When the southern portion melts due to carbon emissions crossing more than 1000 gigatons, sea level rise will be about 1.8 meters or almost six feet.
If emissions cross more than 2500 gigatons due to human activity and global warming, the entire ice sheet would melt leading to sea level rise by nearly seven meters or close to 23 feet.
Causes of Greenland Ice Sheet Melting
Air and water temperature, ocean currents, precipitation, and other factors all determine how quickly the Greenland ice sheet melts and where it loses ice. These are major contributors to rising sea levels across the globe. However, measuring this impact is a challenging task because it happens over extended timescales.
Further complicating matters is that as the Greenland ice sheet melts, its surface drops to lower elevations exposing it to warmer air temperatures, which accelerate melting, making it drop and warm further.
The complexity of these factors makes it challenging to accurately predict how the ice sheet will respond to different climate and carbon emissions scenarios over an extended period.
Solutions to the Greenland Ice Sheet Melting
Reduction of atmospheric carbon-dioxide levels to preindustrial levels is insufficient to permit significant regrowth of the Greenland ice sheet. Artificial carbon-dioxide removal technology could claw back probable melting; however, as of now, this technology does not exist on a scale large enough to deal with current or anticipated carbon emissions.
Future generations will be unable to stop the melting entirely, and Greenland’s ice sheet could melt completely with global warming somewhere between 1 and 3 degrees Celsius. This shows the importance of reducing our carbon emissions for future generations’ benefit.
Image Source: Wikimedia Commons
