Quantcast

Melting Greenland Could Raise Sea Levels by 20 Feet

Thomas Neumann, NASA GSFC

By Madison Feser

Two miles thick and covering an area seven times the size of the United Kingdom, Greenland's ice sheet is huge. It's also melting.

As the ice melts, it gives way to water, which is darker and absorbs far more sunlight, causing more ice to melt in a vicious cycling.


Even worse is the proliferation of dark colored algae, which warm weather has allowed to flourish.

In general, the white color of snow reflects nearly 90 percent of the sun's radiation, but the dark colored algae reflects only around 35 percent, and sometimes drops to a dangerous 1 percent in the darkest colored spots.

At the current rate of melting, the ice sheet adds 1 millimeter a year to the global average sea level. Using these numbers, the UN Climate Change panel reported in 2013 that, worst case scenario, Greenland's melting ice sheets would raise water levels 98 centimeters, or 3.2 feet, by the end of the century.

And now, it seems, that assessment is too modest.

Over the last 20 years, Greenland has been losing more ice than it gains each winter.

Glaciologist Dr. Andrew Tedstone told BBC that the algae has not even reached maximum darkness, and melting will get worse.

According to Dr. Joe Cook, a glacial microbiologist at Sheffield University, it would not even take the whole ice sheet melting to dangerously raise sea levels.

Satellites see unprecedented Greenland ice sheet surface melt.Nicolo E. DiGirolamo, SSAI/NASA GSFC, and Jesse Allen, NASA Earth Observatory

"When we say the ice sheet is melting faster, no one saying it's all going to melt in next decade or the next 100 years or even the next 1,000 years but it doesn't all have to melt for more people to be in danger," he said. "Only a small amount has to melt to threaten millions in coastal communities around world."

However, if the whole ice sheet does melt, sea levels across the world would rise by more than 20 feet.

The UK-based research project, Black and Bloom, is investigating different species of algae and their spread, hoping to limit their impact in Greenland.

But while Black and Bloom is working to combat algae and dark spots, yet another environmental factor is contributing to increased rates of melting.

Stefan Hofer, a PhD student at Bristol, found that decreased cloud cover over the area has caused two-thirds of recent melting.

After analysis satellite imagery, Hofer published a report arguing that over the last 20 years, cloud cover over Greenland has decreased by 15 percent in the summer months.

Lack of cloud cover increases surface temperature on the ice and may foster the growth of more dark algae, both of which accelerate the ice sheet's melting.

Annual Accumulated Melt over Greenland 1979 through 2007 [HD Video]

In two years, Black and Bloom, plans to release new figures on sea levels rising based on their research at the Greenland ice sheet.

Greenland is not the only ice sheet at risk of climate change.

Earlier this summer, a trillion-ton iceberg the size of Delaware broke off from Antarctica. The iceberg was part of larger ice shelf that, should if collapse, will raise sea levels substantially. Temperatures in Antarctica have been increasing at a faster rate than the rest of the world, weakening ice throughout the region.

Even the glaciers in Montana's Glacier National Park are fading away. Over the last 50 years, 39 of the park's glaciers have melted by 85 percent. In the 19th century, the park was home to 150 glaciers, but today only 26 remain

Reposted with permission from our media associate Global Citizen.

Sponsored
On thin ice. Christopher Michel / Flickr / CC BY 2.0

The Russian military is taking measures to protect the residents of a remote Arctic settlement from a mass of polar bears, German press agency DPA reported.

The move comes after regional authorities declared a state of emergency over the weekend after sightings of more than 50 bears in the town of Belushya Guba since December.

Read More Show Less

This year's letter from Bill and Melinda Gates focused on nine things that surprised them. For the Microsoft-cofounder, one thing he was surprised to learn was the massive amount of new buildings the planet should expect in the coming decades due to urban population growth.

"The number of buildings in the world is going to double by 2060. It's like we're going to build a new New York City every month for the next 40 years," he said.

Read More Show Less
Sponsored

Over the past few years, it seems vegan cooking has gone from 'brown rice and tofu' to a true art form. These amazing cooks show off the creations on Instagram—and we can't get enough.

Read More Show Less
The USS Ashland, followed by the USS Green Bay, in the Philippine Sea on Jan. 21. U.S. Department of Defense

By Shana Udvardy

After a dearth of action on climate change and a record year of extreme events in 2017, the inclusion of climate change policies within the annual legislation Congress considers to outline its defense spending priorities (the National Defense Authorization Act) for fiscal year 2018 was welcome progress. House and Senate leaders pushed to include language that mandated that the Department of Defense (DoD) incorporate climate change in their facility planning (see more on what this section of the bill does here and here) as well as issue a report on the impacts of climate change on military installations. Unfortunately, what DoD produced fell far short of what was mandated.

Read More Show Less
The Paradise Fossil Plant in western Kentucky. CC BY 3.0

Trump is losing his rallying cry to save coal. The Tennessee Valley Authority (TVA) voted on Thursday to retire two coal-fired power plants in the next few years despite a plea from the president to keep one of the plants open.

Earlier this week, the president posted an oddly specific tweet that urged the government-owned utility to save the 49-year-old Paradise 3 plant in Kentucky. It so happens that the facility burns coal supplied by Murray Energy Corporation, whose CEO is Robert Murray, is a major Trump donor.

Read More Show Less