STREAMING NOW: Watch Now

A massive waterfall formed on Greenland's ice sheet. Here's why it matters

Climate change in Greenland is threatening the fishing and hunting traditions that sustain father and son Niels and Edward Poulsen's Inuit way of life.

Posted: Dec 4, 2019 5:20 PM
Updated: Dec 4, 2019 5:20 PM

What may have been the world's tallest waterfall briefly formed on Greenland's ice sheet last year, draining a meltwater lake of 5 million cubic meters of water -- equivalent to 2,000 Olympic-sized swimming pools -- in just five hours.

Scientists from the University of Cambridge in the UK recorded the extraordinary phenomenon through the use of aerial drones.

Their study, published this week in the journal Proceedings of the National Academy of Sciences, investigates the link between this transfer of meltwater to the bottom of the ice and rising global sea levels. Greenland has the world's second-largest ice sheet, and is the single largest contributor to global sea-level rise, the study said.

"Before this study, we already knew that many lakes drain and that fractures may be important in the lake drainage process, but the formation of fractures in terms of 'where', 'when' and 'how' has not been studied before, at least not with the resolution and details featured in our work," one of the researchers, Poul Christoffersen, from Cambridge's Scott Polar Research Institute, who led the research told CNN via e-mail.

Caused by cracks forming on the ice sheet, these cascades are responsible for dumping huge quantities of surface water to the ice bed, where it can accelerate the movement of ice towards the sea. After draining, lakes leave behind holes called moulins, which allow meltwater to continue to travel to the bottom of the ice sheet.

"When trigger lakes drain, the water lubricates the bed and the ice flow becomes faster," Christoffersen said.

"Previously this acceleration was thought to be short-lived, and have little overall impact on the ice sheet, but we have shown that even localized and short-lived accelerations caused by the drainage of trigger lakes can open fractures and result in additional drainages of lakes in a more stable setting."

Formed during the summer as the weather warms, the 'trigger lakes' such as the one the scientists observed at Store Glacier, in northwest Greenland, can cause a chain-reaction so that up to 50 or more lakes nearby can drain rapidly over the course of a few days, Christoffersen said.

At its peak, the cascade was 950 cubic meters per second, which is roughly half of the flow of Niagara Falls or one Olympic sized swimming pool every three seconds, he said. The water was plunging "pretty much exactly" 1,000 meters (3,281 feet), said Christoffersen.

Angel Falls in Venezuela is the world's highest waterfall, standing at around 3,210 feet.

"This discharge increased the ice flow from two meters per day to five meters per day as the water delivery took place. This acceleration had a sudden impact on the ice sheet in terms of stress and ice deformation, and these dynamic impacts explain why lakes situated in places where fractures do not naturally form, still drain rapidly," said Christoffersen.

The team used GPS-fitted, autonomous drones to take about 900 photographs of the lake's disappearance.

The photographs were stitched together and made into 3D surface elevation models, Christoffersen said.

Christoffersen said climate change plays a key role in the increase of meltwater production, as global temperatures rise.

"More and more melt water is being produced and melting extends to higher and higher elevations," he said. "Lakes are growing larger and more numerous and forming at higher elevations. Some as high as 2 kilometers above sea level. This means that networks of lakes draining in cascading events are likely to grow larger."

"It's possible we've under-estimated the effects of these glaciers on the overall instability of the Greenland Ice Sheet," said co-first author Tom Chudley, a PhD student at the Scott Polar Research and the team's drone pilot. "It's a rare thing to actually observe these fast-draining lakes -- we were lucky to be in the right place at the right time."

Minnesota Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 55947

Reported Deaths: 1654
CountyConfirmedDeaths
Hennepin17789819
Ramsey6861261
Dakota3942102
Anoka3327112
Stearns281720
Washington188643
Nobles17456
Olmsted162023
Scott136214
Mower10782
Rice9898
Blue Earth8485
Wright8015
Carver7692
Clay74340
Kandiyohi6701
Sherburne6387
St. Louis42719
Todd4182
Lyon4153
Freeborn3541
Steele3271
Nicollet30713
Benton3043
Watonwan2980
Winona24516
Crow Wing20613
Martin2035
Le Sueur1991
Beltrami1910
Chisago1761
Goodhue1758
Otter Tail1753
Cottonwood1710
Pipestone1439
Becker1421
McLeod1350
Unassigned13540
Douglas1290
Itasca12912
Polk1293
Waseca1280
Pine1260
Carlton1240
Dodge1220
Murray1221
Isanti1080
Chippewa971
Brown832
Meeker832
Morrison831
Faribault820
Sibley782
Wabasha780
Koochiching733
Rock730
Jackson700
Pennington701
Mille Lacs643
Fillmore610
Cass582
Renville585
Lincoln540
Swift521
Grant491
Yellow Medicine490
Roseau450
Houston400
Pope390
Norman340
Redwood300
Aitkin280
Hubbard280
Kanabec281
Marshall280
Wilkin283
Mahnomen231
Wadena230
Big Stone220
Red Lake190
Lake170
Stevens150
Clearwater140
Traverse100
Lac qui Parle60
Kittson40
Cook20
Lake of the Woods10

Iowa Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 45592

Reported Deaths: 877
CountyConfirmedDeaths
Polk9709202
Woodbury364250
Black Hawk299762
Linn208987
Johnson191815
Dallas178735
Buena Vista178412
Scott159012
Dubuque152729
Marshall138324
Pottawattamie121223
Story111013
Wapello84531
Muscatine82448
Crawford7153
Webster7125
Sioux5932
Cerro Gordo58117
Tama53729
Warren5261
Jasper45424
Plymouth4438
Wright4411
Louisa37814
Dickinson3754
Clinton3123
Washington28710
Hamilton2391
Boone2282
Franklin2134
Bremer1877
Clarke1853
Carroll1811
Emmet1791
Clay1711
Hardin1660
Shelby1591
Marion1520
Allamakee1494
Poweshiek1468
Benton1421
Des Moines1392
Jackson1391
Mahaska13617
Guthrie1265
Floyd1242
Jones1231
Cedar1201
Hancock1162
Butler1132
Pocahontas1131
Henry1123
Buchanan1101
Lyon1000
Madison1002
Cherokee971
Clayton973
Harrison960
Taylor930
Lee923
Delaware901
Monona900
Humboldt891
Iowa881
Winneshiek821
Calhoun812
Mills810
Sac810
Fayette790
Jefferson780
Palo Alto780
Kossuth770
Osceola770
Mitchell760
Page740
Winnebago730
Grundy721
Union701
Monroe667
Worth610
Chickasaw500
Davis491
Howard480
Cass471
Appanoose433
Lucas434
Montgomery433
Greene380
Fremont360
Van Buren311
Keokuk301
Ida290
Audubon281
Decatur210
Ringgold211
Adair200
Adams160
Wayne151
Unassigned70
Rochester
Clear
56° wxIcon
Hi: 69° Lo: 47°
Feels Like: 56°
Mason City
Clear
54° wxIcon
Hi: 70° Lo: 48°
Feels Like: 54°
Albert Lea
Clear
55° wxIcon
Hi: 68° Lo: 48°
Feels Like: 55°
Austin
55° wxIcon
Hi: 70° Lo: 47°
Feels Like: 55°
Charles City
Clear
55° wxIcon
Hi: 68° Lo: 48°
Feels Like: 55°
Some more rain in the forecast
KIMT Radar
KIMT Eye in the sky

Latest Video

Image

Sara's 6pm Forecast - Monday

Image

Was the summer sports season a success in Iowa?

Image

Primary Election voter registration

Image

Religious Leaders Ask For Mask Mandate

Image

Extra Hands Free Enforcement

Image

Mask Up Rochester

Image

Community adapting to changes at Rochester parks

Image

Fire-related fatalities increase in Minnesota

Image

Sean's Weather 8/3

Image

Campaign signs in Albert Lea

Community Events