That's why tipping points like Greenland's accelerate ice … Scott has written about science and technology for 20 years for publications around the world. Right now, Briner says current melt rates track closely with this worst-case scenario. Scientists estimate that if all of Greenland's ice melted, sea levels would rise by 23 feet. During this year alone, it lost enough ice to … Updated 3:15 PM ET, Wed September 30, 2020 Meltwater carves into the ice sheet near the Sermeq Avangnardleq glacier in Greenland in August 2019. Until 2000, the main driver of sea level rise was melting glaciers and the expansion of ocean water as it warms. Back in April, a study published in The Cryosphere suggested that atmospheric circulation patterns contributed in a significant way to Greenland’s rapid loss of ice and as such, the future melt forecasts could’ve been underestimated by half. About 20 years however, ice melt started increasing, while snowfall remained the same; a pattern that has persisted throughout the last 10 years. It contains enough ice to raise sea levels by 23 feet (7 meters). Holes in Greenland Ice Sheet Are Larger Than Previously Thought, Study Finds Holes that carry surface meltwater to the base of the Greenland ice sheet, called moulins, are much larger than previously thought, according to a new study based on observation and first-hand exploration by a team including a geologist from the University of Arkansas . Whether the rapid disintegration we're seeing on Greenland today compares to anything that has happened in the past is a question on which the science is not completely clear. We present a 1986 through March 2020 estimate of Greenland Ice Sheet ice discharge. On 20 August 2020, scientists reported that the Greenland ice sheet lost a record amount of 532 billion metric tons of ice during 2019, surpassing the old record of 464 billion metric tons in 2012 and returning to high melt rates, and provide explanations for the reduced ice loss in 2017 and 2018. Greenland's ice sheet contains enough water to, Melting from Antarctica, on the other hand, is. It contains enough ice to raise sea levels by 23 feet (7 meters). Overall, melting on the Greenland ice sheet for 2019 was the seventh-highest since 1978, behind 2012, 2010, 2016, 2002, 2007, and 2011 (Figure 2). The Greenland ice sheet is about the same size as the state of Alaska and 10,000 feet thick in places. Opinions expressed by Forbes Contributors are their own. “What we’ve found is that the ice that’s discharging into the ocean is far surpassing the snow that’s accumulating on the surface of the ice sheet.”. Meltwater carves into the ice sheet near the Sermeq Avangnardleq glacier in Greenland in August 2019. Dynamic ice loss from the Greenland Ice Sheet driven by sustained glacier retreat, Nature Communications Earth & Environment (2020). What happens to Greenland's ice sheet and others around the globe will determine what the future holds for the millions of people living along the world's coasts. More information: Michalea D. King et al. But new research shows the rate of ice loss is ramping up, and will be the fastest in 12,000 years by 2100. They discovered that during the 1980s and 90s, the size of the ice sheet was maintained by a combination of snowfall accumulation and ice melting or calving from glaciers, retaining an equilibrium of sorts. Surface melting on the Greenland ice sheet ramped down at a near-normal pace in the weeks following the major melt event of early August (Figure 1). Then the last intact ice shelf in the Canadian Arctic, the Milne Ice Shelf, did collapse losing a chunk of ice bigger than Manhattan to the ocean. The paper was coincidentally released on the same day that the US National Oceanic and Atmospheric Administration reported that July 2020 was the second-warmest July on record and that Arctic ice is currently at a record low for summer – the lowest in 42 years of record-keeping. The ice sheet then started the melt season on 22 June – around 10 days later than average. By University of Arkansas November 21, 2020 University of Arkansas geosciences associate professor Matt Covington flies a drone on the Greenland ice sheet. Greenland's ice sheet dumps more than 280 billion metric tons of melting ice into the ocean each year. The Greenland and Antarctic ice sheets, which hold enough frozen water to lift oceans 65 metres, are tracking the UN's worst-case scenarios for sea level rise, researchers said Monday, highlighting flaws in current climate change models. The Greenland ice sheet is about the same size as the state of Alaska and 10,000 feet thick in places. The Greenland Ice Sheet has lost mass at an accelerating rate over the last two decades, but limits of early remote sensing restricted examination of localized change at an ice‐sheet‐wide scale. Greenland's ice sheet -- which contains enough water to raise global sea levels by 24 feet -- is melting as fast as at any time in the last 12,000 years, a new study finds. Consequently, even if climate change to halted, suddenly, enough damage has been done that the glaciers would continue to disappear into the oceans and there would not be enough snowfall by far to rebuild them during the winter. In 2012, category two Hurricane Sandy clipped New York City, causing $70 billion in damage, flooding subway tunnels and the Brooklyn-Battery tunnel – and that was a 14 foot storm surge. "These results say that human decisions about our energy systems are truly important in deciding how much sea level rise we face from melting of Greenland's ice. Even if global warming were to stop today, the ice sheet would continue shrinking. All Rights Reserved, This is a BETA experience. Now, according to a new paper published in the journal Nature Communications Earth and Environment, Greenland’s glaciers have shrunk so much that even if global warming were to stop right now, the ice sheet would continue shrinking. Our data include all discharging ice that flows faster than 100 m yr −1 and are generated through an automatic and adaptable method, as opposed to conventional handpicked gates. “We are measuring the pulse of the ice sheet — how much ice glaciers drain at the edges of the ice sheet — which increases in the summer,” King said in the researchers’ statement. Meltwater from the Greenland ice sheet represents the largest contribution to current global sea level rise. July 10, 2019 — Ice on the Greenland Ice Sheet doesn't just melt. In the 1980s and 1990s, Greenland’s ice maintained a rough equilibrium. However, if the world resolves to slash emissions enough so that global warming peaks around 2050, ice losses this century could be held to 8,800 billion tons -- still a massive amount, but only enough to raise sea levels by about an inch, compared to the roughly 4 additional inches we can expect under a high-emissions scenario. Greenland's massive ice sheet may have melted by a record amount this year, scientists have warned. Melt of Greenland ice sheet (GrIS) plays important roles in sea level change, global climate, and other areas of global environmental issues. Satellite microwave remote sensing has been increasingly used to produce maps of snow melt over Greenland during the past decades. © 2020 Forbes Media LLC. In 2019, Greenland's ice sheet lost 15% more ice than the previous record set in 2012, the study found. Greenland's melting ice sheet – in pictures Visitors look out on to free-floating ice jammed into Ilulissat Icefjord in Greenland during unseasonably warm weather in July 2019. "We know there's a lot of year-to-year variability, so what we were interested in doing is capturing the more meaningful trends over decades and maybe up to a century," said Jason Briner, a professor of geology at the University at Buffalo and the lead author of the study. Under a scenario where humans continue to raise concentrations of heat-trapping gases in the atmosphere, Greenland's ice loss could reach unprecedented levels, with more than 35,900 billion tons of ice potentially lost by the end of this century. We position gates near the present-year termini and estimate problematic bed topography (ice thickness) values where necessary. Melting of the Greenland Ice Sheet (GrIS) is the largest single contributor to eustatic sea level and is amplified by the growth of pigmented algae on the ice surface, which increases solar radiation absorption. MARLOWE HOOD, AFP . “And what we see is that it was relatively steady until a big increase in ice discharging to the ocean during a short five- to six-year period.”. But there may very well be mechanisms that are not picked up by the current models for how fast the ice is melting in Greenland. "Clearly, the sea level rise from melting ice 12,000 years ago also affected people, but those people were much more widely spread out, and they didn't have parking garages and integrated modern water systems serving millions of people," said Richard Alley, a professor of geosciences at Penn State University who was not involved with the study published by Nature. Satellite data from the last 40 years shows that Greenland’s glaciers have passed a tipping point of sorts, where the snowfall that replenishes the ice sheet each year cannot keep up with the ice that is flowing into the ocean from glaciers. Over the last two decades, Greenland's ice sheet has melted at a rate of roughly 6,100 billion tons per century, a rate approached only during a warm period that occurred between 7,000 and 10,000 years ago. In terms of its potential to raise sea levels, Greenland is the world's second most important ice sheet, behind only Antarctica. "And when you do that, and think about the direction that Greenland is heading this century, it's pretty clear we're in quite anomalous times.". Fresh snow in late May and early June had delayed the start of ice loss season, in contrast to last year’s very high melt rates around the same time. This biological albedo-reducing effect and its impact upon sea … 1 SEPTEMBER 2020 . How much Greenland melts going forward is up to us. The Brooklyn-Battery tunnel in lower Manhattan after Hurricane Sandy and back to normal. (It takes approximately 360 billion tons of ice to produce one millimeter of global sea-level rise.). You may opt-out by. The influence of human activity. A chart provided by the study authors shows how rapidly Greenland's melt has accelerated, and how unprecedented it is compared to rates that occurred over the last 12,000 years. They then contrasted that with the amount of snowfall each year, which is the way these glaciers get replenished. Greenland's ice sheet experienced the largest outright drop in "surface mass" — or how much mass is lost due to melting compared to mass gained … Ice loss would accelerate even more once the top of the ice sheet, which rises to 10,000 feet above sea level, melts down to a lower and warmer level of the atmosphere. ", Greenland lost more ice last year than in any year on record, Millions more US homes are at risk of flooding than previously known, new analysis shows, a new study published in the journal Nature provides some answers, currently responsible for 20-25% of global sea level rise, Antarctica holds enough water to raise sea levels by about 200 feet, discovered alarming vulnerabilities in some of its most important glaciers, Flooding from sea level rise could cost our planet $14.2 trillion, study says, A report last year from the UN's Intergovernmental Panel on Climate Change, already causing problems in many coastal areas. Melt brings about more melt, as water pooling across the ice sheet absorbs more sunlight and further heats everything around it. This is suggested by new results from a groundbreaking international research project headed by DTU Space. Greenland’s ice sheet shrank between 10,000 and 7,000 years ago, and has been slowly cumulating over the past 4,000 years. (CNN)We've known for some time now that Greenland's ice sheet is melting at an alarming rate. Ice Sheet Melting Is Perfectly in Line With Our Worst-Case Scenario, Scientists Warn . Melting Of Greenland’s Ice Sheets Has Passed The Point Of No Return, Scientists Say Scott Snowden Contributor Opinions expressed by Forbes Contributors are their own. The ice actually slides rapidly across its bed toward the ice sheet's edges. October 1, 2020 8:04PM (UTC) The ice sheet that covers most of Greenland, the world's largest island, is on pace to start melting faster than it has in the past 12,000 years. Wednesday, November 18, 2020. Each year the sheet lost some 400bn tonnes of ice in the summer—both by ice and snow melting … Abstract. Throughout this two decade period, the researchers found that the ice sheets lost on average about 450 billion tons of ice each year from flowing outlet glaciers, which was replaced with snowfall. Study co-author Ian Howat, professor of earth sciences and distinguished university scholar at Ohio State said, “Even if the climate were to stay the same or even get a little colder, the ice sheet would still be losing mass.”. EY & Citi On The Importance Of Resilience And Innovation, Impact 50: Investors Seeking Profit — And Pushing For Change, Michigan Economic Development Corporation BrandVoice.