Science
Satellite launched to map the world’s oceans, lakes, rivers
A U.S.-French satellite that will map almost all of the world’s oceans, lakes and rivers rocketed into orbit Friday.
The predawn launch aboard a SpaceX rocket from Vandenberg Space Force Base in California capped a highly successful year for NASA.
Read more: NASA Orion capsule safely blazes back from moon, aces test
Nicknamed SWOT — short for Surface Water and Ocean Topography — the satellite is needed more than ever as climate change worsens droughts, flooding and coastal erosion, according to scientists.
“We’re going to be able to see things that we could just not see before ... and really understand where water is at any given time,” said Benjamin Hamlington at NASA’s Jet Propulsion Laboratory in Pasadena, California.
About the size of an SUV, the satellite will measure the height of water on more than 90% of Earth’s surface, allowing scientists to track the flow and identify potential high-risk areas. It will also survey millions of lakes as well as 1.3 million miles (2.1 million kilometers) of rivers, from headwater to mouth.
The satellite will shoot radar pulses at Earth, with the signals bouncing back to be received by a pair of antennas, one on each end of a 33-foot (10-meter) boom.
It should be able to make out currents and eddies less than 13 miles (21 kilometers) across, as well as areas of the ocean where water masses of varying temperatures merge.
NASA’s current fleet of nearly 30 Earth-observing satellites cannot make out such slight features. And while these older satellites can map the extent of lakes and rivers, their measurements are not as detailed, said the University of North Carolina’s Tamlin Pavelsky, who is part of the mission.
Perhaps most importantly, the satellite will reveal the location and speed of rising sea levels and the shift of coastlines, key to saving lives and property. It will cover the globe between the Arctic and Antarctica at least once every three weeks, as it orbits more than 550 miles (890 kilometers) high. The mission is expected to last three years.
NASA and the French Space Agency collaborated on the $1.2 billion project, with Britain and Canada chipping in.
Read more: Nasa issues second image of ‘Pillars of Creation’ taken by James Webb telescope
“What a spectacular, truly spectacular, launch,” said NASA program manager Nadya Vinogradova-Shiffer. “It is a pivotal moment, and I’m very excited about it.”
Already recycled, the first-stage booster returned to Vandenberg eight minutes after liftoff to fly again one day.
It’s the latest milestone this year for NASA. Among the other highlights: glamour shots of the universe from the new Webb Space Telescope; the Dart spacecraft’s dead-on slam into an asteroid in the first planetary defense test; and the Orion capsule’s recent return from the moon following a test flight.
NASA Orion capsule safely blazes back from moon, aces test
NASA’s Orion capsule made a blisteringly fast return from the moon Sunday, parachuting into the Pacific off Mexico to conclude a test flight that should clear the way for astronauts on the next lunar flyby.
The incoming capsule hit the atmosphere at Mach 32, or 32 times the speed of sound, and endured reentry temperatures of 5,000 degrees Fahrenheit (2,760 degrees Celsius) before splashing down west of Baja California near Guadalupe Island. A Navy ship quickly moved in to recover the spacecraft and its silent occupants — three test dummies rigged with vibration sensors and radiation monitors.
NASA hailed the descent and splashdown as close to perfect, as congratulations poured in from Washington..
“I'm overwhelmed,” NASA Administrator Bill Nelson said from Mission Control in Houston. “This is an extraordinary day ... It's historic because we are now going back into space — deep space — with a new generation.”
Read more: NASA's Orion capsule reaches moon, last big step before lunar orbit
The space agency needed a successful splashdown to stay on track for the next Orion flight around the moon, targeted for 2024 with four astronauts who will be revealed early next year. That would be followed by a two-person lunar landing as early as 2025 and, ultimately, a sustainable moon base. The long-term plan would be to launch a Mars expedition by the late 2030s.
Astronauts last landed on the moon 50 years ago. After touching down on Dec. 11, 1972, Apollo 17′s Eugene Cernan and Harrison Schmitt spent three days exploring the valley of Taurus-Littrow, the longest stay of the Apollo era. They were the last of the 12 moonwalkers.
Orion was the first capsule to visit the moon since then, launching on NASA’s new mega moon rocket from Kennedy Space Center on Nov. 16. It was the first flight of NASA’s new Artemis moon program, named after Apollo’s mythological twin sister.
“From Tranquility Base to Taurus-Littrow to the tranquil waters of the Pacific, the latest chapter of NASA’s journey to the moon comes to a close. Orion back on Earth,” announced Mission Control commentator Rob Navias.
While no one was on the $4 billion test flight, NASA managers were thrilled to pull off the dress rehearsal, especially after so many years of flight delays and busted budgets. Fuel leaks and hurricanes conspired for additional postponements in late summer and fall.
In an Apollo throwback, NASA held a splashdown party at Houston’s Johnson Space Center on Sunday, with employees and their families gathering to watch the broadcast of Orion’s homecoming. Next door, the visitor center threw a bash for the public.
Getting Orion back intact after the 25-day flight was NASA’s top objective. With a return speed of 25,000 mph (40,000 kph) — considerably faster than coming in from low-Earth orbit — the capsule used a new, advanced heat shield never tested before in spaceflight. To reduce the gravity or G loads, it dipped into the atmosphere and briefly skipped out, also helping to pinpoint the splashdown area.
Read more: NASA’s newest moon rocket lifts off 50 years after Apollo
All that unfolded in spectacular fashion, officials noted, allowing for Orion’s safe return.
“I don't think any one of us could have imagined a mission this successful," said mission manager Mike Sarafin.
Further inspections will be conducted once Orion is back at Kennedy by month’s end. If the capsule checks find nothing amiss, NASA will announce the first lunar crew amid considerable hoopla in early 2023, picking from among the 42 active U.S. astronauts stationed at Houston’s Johnson Space Center.
“People are anxious, we know that,” Vanessa Wyche, Johnson's director, told reporters. Added Nelson: “The American people, just like (with) the original seven astronauts in the Mercury days, are going to want to know about these astronauts.”
The capsule splashed down more than 300 miles (482 kilometers) south of the original target zone. Forecasts calling for choppy seas and high wind off the Southern California coast prompted NASA to switch the location.
Orion logged 1.4 million miles (2.25 million kilometers) as it zoomed to the moon and then entered a wide, swooping orbit for nearly a week before heading home.
It came within 80 miles (130 kilometers) of the moon twice. At its farthest, the capsule was more than 268,000 miles (430,000 kilometers) from Earth.
Orion beamed back stunning photos of not only the gray, pitted moon, but also the home planet. As a parting shot, the capsule revealed a crescent Earth — Earthrise — that left the mission team speechless.
Nottingham Trent University astronomer Daniel Brown said the flight's many accomplishments illustrate NASA's capability to put astronauts on the next Artemis moonshot.
“This was the nail-biting end of an amazing and important journey for NASA’s Orion spacecraft," Brown said in a statement from England.
The moon has never been hotter. Just hours earlier Sunday, a spacecraft rocketed toward the moon from Cape Canaveral. The lunar lander belongs to ispace, a Tokyo company intent on developing an economy up there. Two U.S. companies, meanwhile, have lunar landers launching early next year.
Oldest DNA reveals life in Greenland 2 million years ago
Scientists discovered the oldest known DNA and used it to reveal what life was like 2 million years ago in the northern tip of Greenland. Today, it’s a barren Arctic desert, but back then it was a lush landscape of trees and vegetation with an array of animals, even the now extinct mastodon.
“The study opens the door into a past that has basically been lost,” said lead author Kurt Kjær, a geologist and glacier expert at the University of Copenhagen.
With animal fossils hard to come by, the researchers extracted environmental DNA, also known as eDNA, from soil samples. This is the genetic material that organisms shed into their surroundings — for example, through hair, waste, spit or decomposing carcasses.
Studying really old DNA can be a challenge because the genetic material breaks down over time, leaving scientists with only tiny fragments.
But with the latest technology, researchers were able to get genetic information out of the small, damaged bits of DNA, explained senior author Eske Willerslev, a geneticist at the University of Cambridge. In their study, published Wednesday in the journal Nature, they compared the DNA to that of different species, looking for matches.
The samples came from a sediment deposit called the Kap København formation in Peary Land. Today, the area is a polar desert, Kjær said.
But millions of years ago, this region was undergoing a period of intense climate change that sent temperatures up, Willerslev said. Sediment likely built up for tens of thousands of years at the site before the climate cooled and cemented the finds into permafrost.
Read more: Section of destroyed shuttle Challenger found on ocean floor
The cold environment would help preserve the delicate bits of DNA — until scientists came along and drilled the samples out, beginning in 2006.
During the region's warm period, when average temperatures were 20 to 34 degrees Fahrenheit (11 to 19 degrees Celsius) higher than today, the area was filled with an unusual array of plant and animal life, the researchers reported. The DNA fragments suggest a mix of Arctic plants, like birch trees and willow shrubs, with ones that usually prefer warmer climates, like firs and cedars.
The DNA also showed traces of animals including geese, hares, reindeer and lemmings. Previously, a dung beetle and some hare remains had been the only signs of animal life at the site, Willerslev said.
One big surprise was finding DNA from the mastodon, an extinct species that looks like a mix between an elephant and a mammoth, Kjær said.
Many mastodon fossils have previously been found from temperate forests in North America. That’s an ocean away from Greenland, and much farther south, Willerslev said.
“I wouldn’t have, in a million years, expected to find mastodons in northern Greenland,” said Love Dalen, a researcher in evolutionary genomics at Stockholm University who was not involved in the study.
Because the sediment built up in the mouth of a fjord, researchers were also able to get clues about marine life from this time period. The DNA suggests horseshoe crabs and green algae lived in the area — meaning the nearby waters were likely much warmer back then, Kjær said.
By pulling dozens of species out of just a few sediment samples, the study highlights some of eDNA’s advantages, said Benjamin Vernot, an ancient DNA researcher at Germany’s Max Planck Institute for Evolutionary Anthropology who was not involved in the study.
“You really get a broader picture of the ecosystem at a particular time,” Vernot said. “You don’t have to go and find this piece of wood to study this plant, and this bone to study this mammoth.”
Based on the data available, it’s hard to say for sure whether these species truly lived side by side, or if the DNA was mixed together from different parts of the landscape, said Laura Epp, an eDNA expert at Germany’s University of Konstanz who was not involved in the study.
But Epp said this kind of DNA research is valuable to show “hidden diversity” in ancient landscapes.
Read more: Zombie ice from Greenland will raise sea level 10 inches
Willerslev believes that because these plants and animals survived during a time of dramatic climate change, their DNA could offer a “genetic roadmap” to help us adapt to current warming.
Stockholm University's Dalen expects ancient DNA research to keep pushing deeper into the past. He worked on the study that previously held the “oldest DNA” record, from a mammoth tooth around a million years old.
“I wouldn’t be surprised if you can go at least one or perhaps a few million years further back, assuming you can find the right samples,” Dalen said.
Drug slows Alzheimer's but can it make a real difference?
An experimental Alzheimer’s drug modestly slowed the brain disease’s inevitable worsening, researchers reported Tuesday -- but it remains unclear how much difference that might make in people’s lives.
Japanese drugmaker Eisai and its U.S. partner Biogen had announced earlier this fall that the drug lecanemab appeared to work, a badly needed bright spot after repeated disappointments in the quest for better Alzheimer’s treatments.
Now the companies are providing full results of the study of nearly 1,800 people in the earliest stages of the mind-robbing disease. The data was presented at an Alzheimer’s meeting in San Francisco and published in The New England Journal of Medicine. U.S. regulators could approve the drug as soon as January.
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Every two weeks for 18 months, study participants received intravenous lecanemab or a dummy infusion. Researchers tracked them using an 18-point scale that measures cognitive and functional ability.
Those given lecanemab declined more slowly -- a difference of not quite half a point on that scale, concluded the research team led by Dr. Christopher van Dyck at Yale University.
That’s a hard-to-understand change, but measured a different way, lecanemab delayed patients’ worsening by about five months over the course of the study, Eisai’s Dr. Michael Irizarry told The Associated Press. Also, lecanemab recipients were 31% less likely to advance to the next stage of the disease during the study.
“That translates to more time in earlier stages” when people function better, Irizarry said.
But doctors are divided over how much difference those changes may make for patients and families.
“It is unlikely that the small difference reported in this trial will be noticeable by individual patients,” said Dr. Madhav Thambisetty of the National Institute on Aging, who noted he wasn’t speaking for the government agency.
He said many researchers believe a meaningful improvement would require at least a difference of a full point on that 18-point scale.
But Dr. Ron Petersen, an Alzheimer’s expert at the Mayo Clinic, said the drug’s effect was “a modest one but I think it’s clinically meaningful” -- because even a few months’ delay in progression could give someone a little more time when they’re functioning independently.
The trial is important because it shows a drug that attacks a sticky protein called amyloid -- considered one of several culprits behind Alzheimer’s -- can delay disease progression, said Maria Carrillo, chief science officer for the Alzheimer’s Association.
“We all understand that this is not a cure and we’re all trying to really grasp what it means to slow Alzheimer’s, because this is a first,” Carrillo said.
But any delay in cognitive decline early on could be meaningful for “how much time we have with our loved ones in a stage of disease where we can still enjoy family and outings, vacations, bucket lists,” she said.
Amyloid-targeting drugs can cause side effects that include swelling and bleeding in the brain, and lecanemab did as well. One type of this swelling was seen in about 13% of recipients. Eisai said most were mild or asymptomatic.
Read more: Successful transplant of pig's heart into a human body for the first time
Also, two deaths have been publicly reported among lecanemab users who also were taking blood-thinning medications for other health problems. Eisai said Tuesday the deaths can’t be attributed to the Alzheimer’s drug.
But Mayo’s Petersen said if lecanemab is approved for use in the U.S., he’d avoid prescribing it to people on blood thinners at least initially.
And Thambisetty said the death reports raise concern about how the drug may be tolerated outside of research studies “where patients are likely to be sicker and have multiple other medical conditions.”
The Food and Drug Administration is considering approving lecanemab under its fast-track program, with a decision expected in early January. If approved, it would be the second anti-amyloid drug on the market.
Nearly all treatments available for the 6 million Americans with Alzheimer’s — and millions more worldwide — only temporarily ease symptoms. Scientists don’t yet know exactly how Alzheimer’s forms but one theory is that gunky amyloid buildup plays a key role, although drug after drug that targets it has failed.
In a contentious move last year, the FDA approved the first amyloid-targeting drug, Biogen’s Aduhelm, despite lack of evidence of better patient outcomes. Insurers and many doctors have hesitated to prescribe the pricey drug -- another reason experts have anxiously awaited word of how well the newer lecanemab may work.
If the FDA approves lecanemab, patients and their families will need a voice in deciding whether it’s worth the hassle of IV infusions and the risk of side effects for the chance of at least some delay in progression, Petersen said.
“I don’t think we’re going to stop the disease in its tracks” with just amyloid-targeting drugs, he added, saying it will take a combination of medications that target additional Alzheimer’s culprits.
Researchers are preparing to test lecanemab with other experimental drugs, and how it works in high-risk people before they show the first signs of memory problems.
Section of destroyed shuttle Challenger found on ocean floor
A large section of the destroyed space shuttle Challenger has been found buried in sand at the bottom of the Atlantic, more than three decades after the tragedy that killed a schoolteacher and six others.
NASA’s Kennedy Space Center announced the discovery Thursday.
“Of course, the emotions come back, right?” said Michael Ciannilli, a NASA manager who confirmed the remnant's authenticity. When he saw the underwater video footage, “My heart skipped a beat, I must say, and it brought me right back to 1986 ... and what we all went through as a nation."
It's one of the biggest pieces of Challenger found in the decades since the acciden t, according to Ciannilli, and the first remnant to be discovered since two fragments from the left wing washed ashore in 1996.
Read more: Nasa issues second image of ‘Pillars of Creation’ taken by James Webb telescope
Divers for a TV documentary first spotted the piece in March while looking for wreckage of a World War II plane. NASA verified through video a few months ago that the piece was part of the shuttle that broke apart shortly after liftoff on Jan. 28, 1986. All seven on board were killed, including the first schoolteacher bound for space, Christa McAuliffe.
The underwater video provided “pretty clear and convincing evidence,” said Ciannilli.
The piece is more than 15 feet by 15 feet (4.5 meters by 4.5 meters); it's likely bigger because part of it is covered with sand. Because there are square thermal tiles on the piece, it’s believed to be from the shuttle’s belly, Ciannilli said.
The fragment remains on the ocean floor just off the Florida coast near Cape Canaveral as NASA determines the next step. It remains the property of the U.S. government. The families of all seven Challenger crew members have been notified.
Read more: NASA says spacecraft succeeded in changing asteroid’s orbit
“We want to make sure whatever we do, we do the right thing for the legacy of the crew,” Ciannilli said.
Roughly 118 tons (107 metric tons) of Challenger debris have been recovered since the accident. That represents about 47% of the entire vehicle, including parts of the two solid-fuel boosters and external fuel tank.
Most of the recovered wreckage remains buried in abandoned missile silos at Cape Canaveral Space Force Station. The exception is a left side shuttle panel on display at Kennedy Space Center's visitor complex, alongside the charred cockpit window frame from shuttle Columbia, which broke apart over Texas during reentry in 2003, killing seven astronauts.
Far less has been recovered of Columbia — 42 tons (38 metric tons) representing 38% of the shuttle. The Columbia remains are stored in converted offices inside Kennedy’s massive hangar.
Launched on an exceptionally cold morning, Challenger was brought down by eroded O-ring seals in the right booster. Columbia ended up with a slashed left wing, the result of foam insulation breaking off the external fuel tank at liftoff. Mismanagement was also blamed..
A History Channel documentary detailing the latest Challenger discovery airs Nov. 22.
Nasa issues second image of ‘Pillars of Creation’ taken by James Webb telescope
The US space agency Nasa has issued a second image of the famous "Pillars of Creation" taken by the new super space telescope, James Webb, reported BBC.
This week we get a rendering of the active star-forming region as seen by Webb's Mid-Infrared Instrument (MIRI).
Last week, it was the observatory's Near-Infrared Camera (NIRCam) that was highlighting this remarkable location some 6,500 light-years from Earth.
The pillars lie at the heart of what astronomers refer to as Messier 16 (M16), or the Eagle Nebula.
They are the subject of intense study. Every great telescope is pointed in their direction to try to understand the physics and the chemistry in play as new stars are birthed in great clouds of gas and dust.
Webb, with its 6.5m-wide mirror and high-fidelity sensors, is the latest, biggest and best space observatory to take in the scene.
What's interesting about the new MIRI picture is the choice of wavelengths used to display the pillars.
Ordinarily, astronomers might filter the light to make the dusty columns go very largely translucent, so that their interior, nascent stars can be seen in greater detail. This is what the NIRCam image did: it emphasised the thousands of young blue stars that are present.
And MIRI is capable of taking this approach on another step. But on this occasion, the filtering has selected those wavelengths at which the dust itself actually glows.
"Defying expectations that mid-infrared observations let you see through dust, this stunning image shows that they're also great for studying dust and complex molecules made to glow by the intense light of nearby hot stars," explained Prof Mark McCaughrean, the senior advisor for science at the European Space Agency.
Some of the complex chemistry this helps accentuate involves polycyclic aromatic hydrocarbons, PAHs. These are very carbon-rich compounds. You find them on burnt toast and in the exhaust from motor vehicles. PAHs produced by stars are thought to enrich the carbon content throughout the Universe.
MIRI was developed in a collaborative effort between scientists and engineers from 10 European countries, led by the UK, and Nasa's Jet Propulsion Laboratory.
Its co-principal investigator is Prof Gillian Wright.
"It's simply thrilling to see how well MIRI is performing. It's producing radically new science information - stuff we've never had before," the director of the UK Astronomy Technology Centre told BBC News.
"What we see in this new image is akin to the 'skin' of the pillars, if you like. You can see filamentary structures which are where the stars are starting to burn through the dust. And you can see regions that are dark - they're so dense and cold that they're not even lighting up for MIRI."
James Webb is a collaborative project of the US, European and Canadian space agencies. It was launched in December last year and is regarded as the successor to the Hubble Space Telescope.
NASA says spacecraft succeeded in changing asteroid’s orbit
A spacecraft that plowed into a small, harmless asteroid millions of miles away succeeded in shifting its orbit, NASA said Tuesday in announcing the results of its save-the-world test.
The space agency attempted the test two weeks ago to see if in the future a killer rock could be nudged out of Earth’s way.
“This mission shows that NASA is trying to be ready for whatever the universe throws at us,” NASA Administrator Bill Nelson said during a briefing at the space agency’s headquarters in Washington.
The Dart spacecraft carved a crater into the asteroid Dimorphos on Sept. 26, hurling debris out into space and creating a cometlike trail of dust and rubble stretching several thousand miles (kilometers). It took consecutive nights of telescope observations from Chile and South Africa to determine how much the impact altered the path of the 525-foot (160-meter) asteroid around its companion, a much bigger space rock.
Before the impact, the moonlet took 11 hours and 55 minutes to circle its parent asteroid. Scientists had anticipated shaving off 10 minutes, but Nelson said the impact shortened the asteroid’s orbit by 32 minutes.
“Let’s all just kind of take a moment to soak this in ... for the first time ever, humanity has changed the orbit” of a celestial body, noted Lori Glaze, NASA’s director of planetary science.
Apollo astronaut Rusty Schweickart, a co-founder of the nonprofit B612 Foundation, dedicated to protecting Earth from asteroid strikes, said he’s “clearly delighted, no question about that” by the results and the attention the mission has brought to asteroid deflection.
The team’s scientists said the amount of debris apparently played a role in the outcome. The impact may also have left Dimorphos wobbling a bit, said NASA program scientist Tom Statler. That may affect the orbit, but it will never go back to its original location, he noted.
The two bodies originally were already less than a mile (1.2 kilometers) apart. Now they’re tens of yards (meters) closer.
Neither asteroid posed a threat to Earth — and still don’t as they continue their journey around the sun. That’s why scientists picked the pair for this all-important dress rehearsal.
Planetary defense experts prefer nudging a threatening asteroid or comet out of the way, given years or even decades of lead time, rather than blowing it up and creating multiple pieces that could rain down on Earth.
“We really need to also have that warning time for a technique like this to be effective,” said mission leader Nancy Chabot of Johns Hopkins University’s Applied Physics Laboratory, which built the spacecraft and managed the $325 million mission.
“You’ve got to know they’re coming,” added Glaze.
Launched last year, the vending machine-size Dart — short for Double Asteroid Redirection Test — was destroyed when it slammed into the asteroid 7 million miles (11 million kilometers) away at 14,000 mph (22,500 kph).
“This is huge feat, not only in achieving the first step in possibly being able to protect ourselves from future asteroid impacts,” but also for the amount of images and data collected internationally, Daniel Brown, an astronomer at Nottingham Trent University in England, said via email.
Brown also said that it’s “particularly exciting” that the debris tail can be seen by amateur skygazers with medium-size telescopes.
Team scientists cautioned more work is needed to not only identify more of the countless space rocks out there, but to ascertain their makeup — some are solid, while others are rubble piles. Scouting missions might be needed, for instance, before launching impactors to deflect the orbits.
“We should not be too eager to say one test on one asteroid tells us exactly how every other asteroid would behave in a similar situation,” Statler said.
Nonetheless, he and others are rejoicing over this first effort.
”We’ve been imagining this for years and to have it finally be real is really quite a thrill,” he said.
Zombie ice from Greenland will raise sea level 10 inches
Greenland’s rapidly melting ice sheet will eventually raise global sea level by at least 10.6 inches (27 centimeters) -- more than twice as much as previously forecast — according to a study published Monday.
That's because of something that could be called zombie ice. That's doomed ice that, while still attached to thicker areas of ice, is no longer getting replenished by parent glaciers now receiving less snow. Without replenishment, the doomed ice is melting from climate change and will inevitably raise seas, said study co-author William Colgan, a glaciologist at the Geological Survey of Denmark and Greenland.
“It’s dead ice. It’s just going to melt and disappear from the ice sheet,” Colgan said in an interview. “This ice has been consigned to the ocean, regardless of what climate (emissions) scenario we take now.”
Also read: Pakistan fatal flooding has hallmarks of warming
Study lead author Jason Box, a glaciologist at the Greenland survey, said it is “more like one foot in the grave.”
The unavoidable ten inches in the study is more than twice as much sea level rise as scientists had previously expected from the melting of Greenland’s ice sheet. The study in the journal Nature Climate Change said it could reach as much as 30 inches (78 centimeters). By contrast, last year’s Intergovernmental Panel on Climate Change report projected a range of 2 to 5 inches (6 to 13 centimeters) for likely sea level rise from Greenland ice melt by the year 2100.
What scientists did for the study was look at the ice in balance. In perfect equilibrium, snowfall in the mountains in Greenland flows down and recharges and thickens the sides of glaciers, balancing out what’s melting on the edges. But in the last few decades there’s less replenishment and more melting, creating imbalance. Study authors looked at the ratio of what’s being added to what’s being lost and calculated that 3.3% of Greenland’s total ice volume will melt no matter what happens with the world cutting carbon pollution, Colgan said.
“I think starving would be a good phrase,” for what’s happening to the ice, Colgan said.
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One of the study authors said that more than 120 trillion tons (110 trillion metric tons) of ice is already doomed to melt from the warming ice sheet’s inability to replenish its edges. When that ice melts into water, if it were concentrated only over the United States, it would be 37 feet (11 meters) deep.
The figures are a global average for sea level rise, but some places further away from Greenland would get more and places closer, like the U.S. East Coast, would get less. Although 10.6 inches may not sound like much, this would be over and above high tides and storms, making them even worse, so this much sea level rise “will have huge societal, economic and environmental impacts,” said Ellyn Enderlin, a geosciences professor at Boise State University, who wasn't part of the study.
“This is a really large loss and will have a detrimental effect on coastlines around the world,” said NYU’s David Holland who just returned from Greenland, but is not part of the study.
This is the first time scientists calculated a minimum ice loss — and accompanying sea level rise — for Greenland, one of Earth’s two massive ice sheets that are slowly shrinking because of climate change from burning coal, oil and natural gas. Scientists used an accepted technique for calculating minimum committed ice loss, the one used on mountain glaciers for the entire giant frozen island.
Pennsylvania State University glaciologist Richard Alley, who wasn’t part of the study but said it made sense, said the committed melting and sea level rise is like an ice cube put in a cup of hot tea in a warm room.
“You have committed mass loss from the ice," Alley said in an email. "In the same way, most of the world’s mountain glaciers and the edges of Greenland would continue losing mass if temperatures were stabilized at modern levels because they have been put into warmer air just as your ice cube was put in warmer tea."
Time is the key unknown here and a bit of a problem with the study, said two outside ice scientists, Leigh Stearns of the University of Kansas and Sophie Nowicki of the University of Buffalo. The researchers in the study said they couldn't estimate the timing of the committed melting, yet in the last sentence they mention, “within this century,” without supporting it, Stearns said.
Colgan responded that the team doesn’t know how long it will take for all the doomed ice to melt, but making an educated guess, it would probably be by the end of this century, or at least by 2150.
Colgan said this is actually all a best case scenario. The year 2012 (and to a different degree 2019 ) was a huge melt year, when the equilibrium between adding and subtracting ice was most out of balance. If Earth starts to undergo more years like 2012, Greenland melt could trigger 30 inches (78 centimeters) of sea level rise, he said. Those two years seem extreme now, but years that look normal now would have been extreme 50 years ago, he said.
“That’s how climate change works,” Colgan said. “Today’s outliers become tomorrow’s averages.”
NASA scrubs launch of new moon rocket after engine problem
NASA called off the launch of its mighty new moon rocket on its debut flight with three test dummies aboard Monday after a last-minute cascade of problems culminating in unexplained trouble related to an engine.
The next launch attempt will not take place until Friday at the earliest and could be delayed until mid-September or later.
The mission will be the first flight in NASA's Artemis project, a quest to put astronauts back on the moon for the first time since the Apollo program ended 50 years ago.
As precious minutes ticked away Monday morning, NASA repeatedly stopped and started the fueling of the Space Launch System rocket because of a leak of highly explosive hydrogen, eventually succeeding in reducing the seepage. The leak happened in the same place that saw seepage during a dress rehearsal in the spring.
Also read: Fuel leak interrupts launch countdown of NASA moon rocket
The fueling already was running nearly an hour late because of thunderstorms off Florida’s Kennedy Space Center.
Then, NASA ran into new trouble when it was unable to properly chill one of the rocket's four main engines, officials said. Engineers struggled to pinpoint the source of the problem well after the launch postponement was announced.
Mission manager Mike Sarafin said the fault did not appear to be with the engine itself but with the plumbing leading to it.
Complicating matters, as engineers were trying to troubleshoot that problem on the launch pad, yet another hydrogen leak developed, this one involving a vent valve higher up on the rocket, Sarafin said.
“This is a very complicated machine, a very complicated system, and all those things have to work, and you don’t want to light the candle until it’s ready to go," said NASA Administrator Bill Nelson.
Also read: NASA tests new moon rocket, 50 years after Apollo
Referring to launch delays, he said: “It’s just part of the space business and it’s part of, particularly, a test flight.”
The rocket was set to lift off on a flight to propel a crew capsule into orbit around the moon. The six-week mission was scheduled to end with the capsule returning to Earth in a splashdown in the Pacific in October.
The 322-foot (98-meter) spaceship is the most powerful rocket ever built by NASA, out-muscling even the Saturn V that took the Apollo astronauts to the moon.
The dummies inside the Orion capsule were fitted with sensors to measure vibration, cosmic radiation and other conditions during the shakedown flight, meant to stress-test the spacecraft and push it to its limits in ways that would never be attempted if humans were aboard.
Asked about the possibility of another launch attempt on Friday, Sarafin said, “We really need time to look at all the information, all the data. We’re going to play all nine innings here.”
Even though no one was on board, thousands of people jammed the coast to see the rocket soar. Vice President Kamala Harris and Apollo 10 astronaut Tom Stafford were among the VIPs who arrived.
Assuming the shakedown flight goes well, astronauts will climb aboard for the second Artemis mission and fly around the moon and back as soon as 2024. A two-person lunar landing could follow by the end of 2025.
The problems seen Monday were reminiscent of NASA's space shuttle era, when hydrogen fuel leaks disrupted countdowns and delayed a string of launches back in 1990.
Later in the morning, NASA also officials spotted what they feared was a crack or some other defect on the core stage — the big orange fuel tank with four main engines on it — but they later said it appeared to be just a buildup of frost in a crevice of the insulating foam.
Launch director Charlie Blackwell-Thompson and her team also had to deal with sluggish communication between the Orion capsule and launch control. The problem required what turned out to be a simple fix.
Even if there had been no technical snags, thunderstorms ultimately would have prevented a liftoff, NASA said. Dark clouds and rain gathered over the launch site as soon as the countdown was halted, and thunder echoed across the coast.
Pakistan fatal flooding has hallmarks of warming
The familiar ingredients of a warming world were in place: searing temperatures, hotter air holding more moisture, extreme weather getting wilder, melting glaciers, people living in harm’s way, and poverty. They combined in vulnerable Pakistan to create unrelenting rain and deadly flooding.
The flooding has all the hallmarks of a catastrophe juiced by climate change, but it is too early to formally assign blame to global warming, several scientists tell The Associated Press. It occurred in a country that did little to cause the warming, but keeps getting hit, just like the relentless rain.
“This year Pakistan has received the highest rainfall in at least three decades. So far this year the rain is running at more than 780% above average levels,” said Abid Qaiyum Suleri, executive director of the Sustainable Development Policy Institute and a member of Pakistan’s Climate Change Council. “Extreme weather patterns are turning more frequent in the region and Pakistan is not a exception.”
Climate Minister Sherry Rehman said “it’s been a catastrophe of unprecedented proportions.”
Also read: Over 33 mln people, 72 districts of Pakistan affected by floods
Pakistan “is considered the eighth most vulnerable country to climate change,” said Moshin Hafeez, a Lahore-based climate scientist at the International Water Management Institute. Its rain, heat and melting glaciers are all climate change factors scientists warned repeatedly about.
While scientists point out these classic climate change fingerprints, they have not yet finished intricate calculations that compare what happened in Pakistan to what would happen in a world without warming. That study, expected in a few weeks, will formally determine how much climate change is a factor, if at all.
The “recent flood in Pakistan is actually an outcome of the climate catastrophe ... that was looming very large,” said Anjal Prakash, a research director at India’s Bharti Institute of Public Policy. “The kind of incessant rainfall that has happened ... has been unprecedented."
Pakistan is used to monsoons and downpours, but “we do expect them spread out, usually over three months or two months,” said the country's climate minister Rehman.
There are usually breaks, she said, and not as much rain -- 37.5 centimeters (14.8 inches) falls in one day, nearly three times higher than the national average for the past three decades. “Neither is it so prolonged. ... It’s been eight weeks and we are told we might see another downpour in September.”
Also read: Pakistan flooding deaths pass 1,000 in 'climate catastrophe'
“Clearly, it’s being juiced by climate change,” said Jennifer Francis, a climate scientist at the Woodwell Climate Research Center in Massachusetts.
There’s been a 400% increase in average rainfall in areas like Baluchistan and Sindh, which led to the extreme flooding, Hafeez said. At least 20 dams have been breached.
The heat has been as relentless as the rain. In May, Pakistan consistently saw temperatures above 45 degrees Celsius (113 Fahrenheit). Scorching temperatures higher than 50 degrees Celsius (122 Fahrenheit) were recorded in places like Jacobabad and Dadu.
Warmer air holds more moisture -- about 7% more per degree Celsius (4% per degree Fahrenheit) — and that eventually comes down, in this case in torrents.
Across the world “intense rain storms are getting more intense,” said Princeton University climate scientist Michael Oppenheimer. And he said mountains, like those in Pakistan, help wring extra moisture out as the clouds pass.
Instead of just swollen rivers flooding from extra rain, Pakistan is hit with another source of flash flooding: The extreme heat accelerates the long-term glacier melting then water speeds down from the Himalayas to Pakistan in a dangerous phenomena called glacial lake outburst floods.
“We have the largest number of glaciers outside the polar region, and this affects us,” climate minister Rehman said. “Instead of keeping their majesty and preserving them for posterity and nature. We are seeing them melt.”
Not all of the problem is climate change.
Pakistan saw similar flooding and devastation in 2010 that killed nearly 2,000 people. But the government didn’t implement plans to prevent future flooding by preventing construction and homes in flood prone areas and river beds, said Suleri of the country's Climate Change Council.
The disaster is hitting a poor country that has contributed relatively little to the world's climate problem, scientists and officials said. Since 1959, Pakistan has emitted about 0.4% of heat-trapping carbon dioxide, compared to 21.5% by the United States and 16.4% by China.
“Those countries that have developed or gotten rich on the back of fossil fuels, which are the problem really,” Rehman said. “They’re going to have to make a critical decision that the world is coming to a tipping point. We certainly have already reached that point because of our geographical location.”