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AI is changing sea ice melting climate projections

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AI is changing sea ice melting climate projections

The tremendous melting of sea ice at the poles is one of the most urgent problems facing planet as it warms up so quickly. These delicate ecosystems, whose survival depends so heavily on floating ice, have a difficult and uncertain future.

As a result, climate scientists are using AI more and more to transform our knowledge of this vital habitat and the actions that can be taken to preserve it.

Determining the precise date at which the Arctic will become ice-free is one of the most urgent problems that must be addressed in order to develop mitigation and preservation strategies. A step toward this, according to Princeton University research scientist William Gregory, is to lower the uncertainty in climate models to produce these kinds of forecasts.

“This study was inspired by the need to improve climate model predictions of sea ice at the polar regions, as well as increase our confidence in future sea ice projections,” said Gregory.

Arctic sea ice is a major factor in the acceleration of global climate change because it cools the planet overall by reflecting solar radiation back into space. But because of climate change brought on by our reliance on gas, oil, and coal, the polar regions are warming considerably faster than the rest of the world. When the sea is too warm for ice to form, more solar radiation is absorbed by the Earth’s surface, which warms the climate even more and reduces the amount of ice that forms.

Because of this, polar sea ice is extremely important even outside of the poles. The Arctic Ocean will probably eventually have no sea ice in the summer, which will intensify global warming’s effects on the rest of the world.

AI coming to the rescue

Predictions of the atmosphere, land, sea ice, and ocean are consistently biased as a result of errors in climate models, such as missing physics and numerical approximations. Gregory and his colleagues decided to use a kind of deep learning algorithm known as a convolutional neural network for the first time in order to get around these inherent problems with sea ice models.

“We often need to approximate certain physical laws in order to save on [computational] time,” wrote the team in their study. “Therefore, we often use a process called data assimilation to combine our climate model predictions together with observations, to produce our ‘best guess’ of the climate system. The difference between best-guess-models and original predictions provides clues as to how wrong our original climate model is.”

The team aims to show a computer algorithm  “lots of examples of sea ice, atmosphere and ocean climate model predictions, and see if it can learn its own inherent sea ice errors” according to their study published in JAMES.

Gregory explained that the neural network “can predict how wrong the climate model’s sea ice conditions are, without actually needing to see any sea ice observations,” which means that once it learns the features of the observed sea ice, it can correct the model on its own.

They achieved this by using climate model-simulated variables such as sea ice velocity, salinity, and ocean temperature. In the model, each of these factors adds to the overall representation of the Earth’s climate.

“Model state variables are simply physical fields which are represented by the climate model,” explained Gregory. “For example, sea-surface temperature is a model state variable and corresponds to the temperature in the top two meters of the ocean.

“We initially selected state variables based on those which we thought a-priori are likely to have an impact on sea ice conditions within the model. We then confirmed which state variables were important by evaluating their impact on the prediction skill of the [neural network],” explained Gregory.

In this instance, the most important input variables were found to be surface temperature and sea ice concentration—much fewer than what most climate models require to replicate sea ice. In order to fix the model prediction errors, the team then trained the neural network on decades’ worth of observed sea ice maps.

An “increment” is an additional value that indicates how much the neural network was able to enhance the model simulation. It is the difference between the initial prediction made by the model without AI and the corrected model state.

A revolution in progress

Though it is still in its early stages, artificial intelligence is becoming more and more used in climate science. According to Gregory, he and his colleagues are currently investigating whether their neural network can be applied to scenarios other than sea ice.

“The results show that it is possible to use deep learning models to predict the systematic [model biases] from data assimilation increments, and […] reduce sea ice bias and improve model simulations,” said Feiyu Lu, project scientist at UCAR and NOAA/GFDL, and involved in the same project that funded this study.

“Since this is a very new area of active research, there are definitely some limitations, which also makes it exciting,” Lu added. “It will be interesting and challenging to figure out how to apply such deep learning models in the full climate models for climate predictions.”  

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Boeing Starliner crews will have an extended stay on the ISS due to SpaceX’s delay

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NASA said on Tuesday that it has decided to postpone the launch until at least late March because SpaceX’s upcoming crew rotation mission to the ISS would utilize a new Dragon spacecraft that won’t be ready by the initial February launch date.

For the two NASA astronauts who traveled to the ISS last June on Boeing’s troubled Starliner spacecraft, that means an even longer stay. On June 5, they took off from Cape Canaveral, Florida, aboard a United Launch Alliance Atlas V on the first crewed mission of Starliner. They arrived at the ISS one day later for a stay that was only expected to last eight days.

NASA decided to be cautious and maintain Butch Wilmore and Suni Williams aboard the ISS while sending Starliner home without a crew due to issues with the spacecraft’s thrusters and helium leaks on its propulsion module.

In order for Williams and Wilmore to have a trip home, they will now be traveling on the SpaceX Crew Dragon Freedom, which traveled up to the ISS and docked in September, although with only two crew members on board rather than the customary four.

When Crew-10 arrived in late February, the mission’s goal was to take a trip home.

However, NASA confirmed that Crew-10 will not fly with its replacement crew until late March. This allows NASA and SpaceX time to prepare the new Dragon spacecraft, which has not yet been given a name, for the voyage. Early January is when it is anticipated to reach Florida.

“Fabrication, assembly, testing, and final integration of a new spacecraft is a painstaking endeavor that requires great attention to detail,” stated Steve Stich, the program manager for NASA’s Commercial Crew. “We appreciate the hard work by the SpaceX team to expand the Dragon fleet in support of our missions and the flexibility of the station program and expedition crews as we work together to complete the new capsule’s readiness for flight.”

It would be the fifth Dragon spacecraft with a crew. Its fleet of four current Dragon spacecraft has flown 15 times, sending 56 passengers to space, including two who were two-time fliers. The first crewed trip took place in May 2020. Each spacecraft’s name is chosen by the crew on its first flight.

According to NASA, teams considered using the other crew Dragon spacecraft that were available but decided that rescheduling Crew-10’s launch date was the best course of action.

JAXA (Japan Aerospace Exploration Agency) astronaut and mission specialist Takuya Onishi will undertake his second spaceflight, Roscosmos cosmonaut and mission specialist Kirill Peskov will make his first spaceflight, NASA astronaut and commander Anne McClain will make her second spaceflight, and NASA astronaut and pilot Nichole Ayers will become the first member of the 2021 astronaut candidate class to reach space.

Given that Crew-9 won’t be able to return home until a handover period following Crew-10’s arrival, Wilmore and Williams may have to spend nearly nine months aboard as a result of the delay.

Rotations aboard the ISS typically last six months.

It is unclear when and how Starliner will receive its final certification so that it can start trading off the regular ferry service with SpaceX, as NASA’s Commercial Crew Program aims to have two providers for U.S.-based rotation missions with SpaceX and Boeing. This is due to the Crew Flight Test mission’s incomplete launch.

According to the terms of its contract, Boeing must deliver six missions to the ISS before the space station’s service ends, which is presently scheduled for 2030.

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Ancient DNA Reveals When Humans and Neanderthals Interbred

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Neanderthals and humans likely mixed and mingled during a narrow time frame 45,000 years ago, scientists reported Thursday.

Researchers analyzed ancient genes to pinpoint the time period, which is slightly more recent than previous estimates for the mating.

Modern humans emerged in Africa hundreds of thousands of years ago and eventually spread to Europe, Asia, and beyond. Somewhere along the way, they met and mated with Neanderthals, leaving a lasting fingerprint on our genetic code.

Scientists don’t know exactly when or how the two groups entangled. But ancient bone fragments and genes are helping scientists figure that out.

“Genetic data from these samples really helps us paint a picture in more and more detail,” said study co-author Priya Moorjani at the University of California, Berkeley.

The research was published Thursday in the journals Science and Nature.

To pin down the timeline, researchers peeked at some of the oldest human genes from the skull of a woman, called Zlatý kůň or Golden Horse, named after a hill in the Czech Republic where it was found. They also examined bone fragments from an early human population in Ranis, Germany, about 140 miles (230 kilometers) away. They found snippets of Neanderthal DNA that placed the mating at around 45,000 years ago.

In a separate study, researchers tracked signs of Neanderthal DNA in our genetic code over 50,000 years. They found Neanderthal genes related to immunity and metabolism that may have helped early humans survive and thrive outside of Africa.

We still carry Neanderthals’ legacy in our DNA. Modern-day genetic quirks linked to skin color, hair color, and even nose shape can be traced back to our extinct former neighbors. And our genetic code also contains echoes from another group of extinct human cousins called Denisovans.

Future genetic studies can help scientists detangle exactly what—and who—we’re made of, said Rick Potts, director of the Smithsonian’s Human Origins program, who was not involved with the new research.

“Out of many really compelling areas of scientific investigation, one of them is: well, who are we?” Potts said.

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NASA postpones the next Artemis flights much more

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NASA has postponed the first crewed landing of the program until mid-2027, delaying the following two Artemis trips to the moon.

After identifying the primary cause of Orion heat shield erosion on the Artemis 1 mission two years ago, NASA leadership announced at a news conference on December 5 that they were postponing the Artemis 2 and 3 flights.

Artemis 2, which was originally planned to launch in September 2025, would now debut in April 2026 under the updated schedule. It will be the first crewed voyage of Orion to take four astronauts from the United States and Canada around the moon.

As a result, Artemis 3, which will use SpaceX’s Starship vehicle for the first crewed landing of the entire exploration effort, will be delayed. Originally scheduled for September 2026, that mission is now anticipated to occur in mid-2027.

Following an examination of Artemis 1’s heat shield deterioration, NASA changed that timeline. In October, agency representatives claimed to have identified the cause of the heat shield material’s release, but they did not elaborate on the cause or NASA’s plans to fix it.

NASA Deputy Administrator Pam Melroy said the issue was related to Orion’s “skip” reentry, in which the capsule enters and exits the atmosphere to release energy. In the outer layers of the heat shield, more heat was retained than anticipated, resulting in trapped gases. “This caused internal pressure to build up and led to cracking and uneven shedding of that outer layer,”  she said.

This judgment was confirmed by an independent review panel after a thorough study. “There were a lot of links in the error chain that accumulated over time that led to our inability to predict this in ground tests,” stated Amit Kshatriya, deputy assistant administrator of NASA’s Moon to Mars Program Office. This included modifications to the shape of the material blocks and modifications to the manufacturing process of the heat shield material, known as Avcoat.

He said that in areas of the Avcoat material with the required greater permeability to let the gasses out, that was verified. “In those places, we did not witness in-flight cracking, and that was the key clue for us.”

NASA will alter the reentry profile, including shortening the skip phase of the reentry, rather than replacing the entire heat shield for the Artemis 2 mission. According to ground tests, those adjustments should be enough to prevent material from breaking off as a result of cracking.

The agency has been working on a number of other Orion issues while looking into the heat shield issue, such as a battery issue that was reported in January but was reportedly fixed, according to Kshatriya.

Despite an upcoming presidential transition that would probably rethink the entire Artemis design, agency chiefs said they made the decision immediately to prevent future delays. “We’re on a day-for-day slip. We had to make this decision,” Melroy stated. “If you’re waiting for a new admininstrator to be confirmed and a team to come up to speed on all this technical work we’ve all been tracking very closely, I think that would be actually far worse.”

Shortly after President-elect Donald Trump stated on December 4 that he would select Jared Isaacman to oversee the agency, NASA Administrator Bill Nelson claimed he spoke with Isaacman. He did, however, add that he and other authorities had a discussion prior to the meetings in which they confirmed the revised plan for Artemis 2 and 3. Melroy went on to say that NASA could have been consulted on the decision, but the incoming administration has not dispatched a transition team there.

Nelson, however, maintained that the present architecture was still the most effective way to send humans back to the moon in spite of the problems and delays, pointing out that even with the most recent postponement, NASA would still make a lunar landing before China’s projected 2030 lunar mission.

“Are they going to axe Artemis and insert Starship?” In reference to the impending Trump administration, Nelson stated. Only Orion is rated for human spaceflight outside of Earth’s orbit, he said. “I expect that this is going to continue.”

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