The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
The first continuous, multi-century study of surface melt from the Greenland ice sheet was published in Nature Wednesday, and the results are clear: the ice sheet is now melting at rates unseen within at least the last 350 years.
"Melting of the Greenland Ice Sheet has gone into overdrive. As a result, Greenland melt is adding to sea level more than any time during the last three and a half centuries, if not thousands of years," lead study author and Rowan University School of Earth & Environment glaciologist Luke Trusel said in a press release from the Woods Hole Oceanographic Institution (WHOI), one of the institutions involved in the research.
Greenland is Melting Faster than Ever www.youtube.com
The researchers found that melting first increased on the ice sheet in the 1800s, when the Arctic began to warm as the process of industrialization started pumping greenhouse gasses into the atmosphere. However, it is only in recent decades that the melting has increased beyond the point of natural variability. There is now 50 percent more meltwater runoff entering the oceans from the sheet since the start of the industrial era, and 30 percent more since the 20th century.
"From a historical perspective, today's melt rates are off the charts, and this study provides the evidence to prove this," WHOI glaciologist and study author Sarah Das said.
The researchers were able to prove what many had sensed through observation by using a novel method, as the WHOI explained:
To determine how intensely Greenland ice has melted in past centuries, the research team used a drill the size of a traffic light pole to extract ice cores from the ice sheet itself and an adjacent coastal ice cap, at sites more than 6,000 feet above sea level. The scientists drilled at these elevations to ensure the cores would contain records of past melt intensity, allowing them to extend their records back into the 17th century. During warm summer days in Greenland, melting occurs across much of the ice sheet surface. At lower elevations, where melting is the most intense, meltwater runs off the ice sheet and contributes to sea level rise, but no record of the melt remains. At higher elevations, however, the summer meltwater quickly refreezes from contact with the below-freezing snowpack sitting underneath. This prevents it from escaping the ice sheet in the form of runoff. Instead, it forms distinct icy bands that stack up in layers of densely packed ice over time.
Using ice cores allowed the researchers to provide more historical context than the satellite data they had relied on up until now to judge melt rates, which only goes back to the 1970s.
"We have had a sense that there's been a great deal of melting in recent decades, but we previously had no basis for comparison with melt rates going further back in time," study author and MIT-WHOI graduate student Matt Osman said. "By sampling ice, we were able to extend the satellite data by a factor of 10 and get a clearer picture of just how extremely unusual melting has been in recent decades compared to the past."
The research has troubling implications for future sea level rise, because it shows that the ice sheet isn't melting at a steady rate. Instead, each degree of warming increases the amount of melting, meaning the more the planet warms, the more sensitive the ice sheet will be.
"Even a very small change in temperature caused an exponential increase in melting in recent years," Das said. "So the ice sheet's response to human-caused warming has been non-linear."
Trusel summed up the implications:
"Warming means more today than it did in the past," he said.
The research is in keeping with estimates that global sea levels will rise by eight to 12 inches by 2050, but University of Lincoln climate scientist Edward Hanna, who was not involved with the study, told InsideClimateNews that sea level rise projections might have to be increased if Greenland keeps melting.
"We can't rule out that the IPCC (Intergovernmental Panel on Climate Change) sea level rise scenarios are too conservative," Hanna said. "Greenland is a bit like a sleeping giant that is awakening. Who knows how it will respond to a couple of more degrees of warming? It could lose a lot of mass very quickly."
EcoWatch Daily Newsletter
Wolves and Jaguars Are Already Threatened by Border Razor Wire As Trump Vetoes Bid to Block Emergency Wall Funding
President Donald Trump issued the first veto of his presidency Friday, overturning Congress' vote to block his national emergency declaration to fund a border wall that environmental advocates say would put 93 endangered species at risk. However, the president's decision came the same day as an in-depth report from UPI revealing how razor wire placed at the border in the last four months already threatens wildlife.
Yet another whale has died after ingesting plastic bags. A young male Cuvier's beaked whale was found washed up in Mabini, Compostela Valley in the Philippines Friday, CNN reported. When scientists from the D' Bone Collector Museum in Davao investigated the dead whale, they found it had died of "dehydration and starvation" after swallowing plastic bags―40 kilograms (approximately 88 pounds) worth of them!
By Joe Sandler Clarke
"Don't expect us to continue buying European products," Malaysia's former plantations minister Mah Siew Keong told reporters in January last year. His comments came just after he had accused the EU of "practising a form of crop apartheid."
A few months later Luhut Pandjaitan, an Indonesian government minister close to President Joko 'Jokowi' Widodo, warned his country would retaliate if it was "cornered" by the EU.
By Luis Torres
For some people who live along the U.S.-Mexico border, President Trump's attempt to declare a national emergency and extend the border wall is worse than a wasteful, unconstitutional stunt. It's an attack on their way of life that threatens to desecrate their loved ones' graves.
At least 150 people have died in a cyclone that devastated parts of Mozambique, Zimbabwe and Malawi over the weekend, The Associated Press reported Sunday. Cyclone Idai has affected more than 1.5 million people since it hit Mozambique's port city of Beira late Thursday, then traveled west to Zimbabwe and Malawi. Hundreds are still missing and tens of thousands are without access to roads or telephones.
"I think this is the biggest natural disaster Mozambique has ever faced. Everything is destroyed. Our priority now is to save human lives," Mozambique's Environment Minister Celso Correia said, as AFP reported.