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The Reversed Changes in Southern Hemisphere Winds – AZoCleantech

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There have been changes in the atmospheric circulation in the Southern Hemisphere caused by the same chemicals that destroy the ozone layer that protects the Earth.

This panoramic image from February 14th, 2014, shows parts of Chile and Argentina from the International Space Station. Image Credit: NASA.

A new study recently published in the Nature journal reports that there has been a break in such changes, which could even reverse, thanks to the Montreal Protocol, an international treaty that successfully eradicated the use of ozone-depleting chemicals.

This study adds to growing evidence showing the profound effectiveness of the Montreal Protocol. Not only has the treaty spurred healing of the ozone layer, it’s also driving recent changes in Southern Hemisphere air circulation patterns.

Antara Banerjee, Study Lead Author and Visiting Fellow, CIRES, University of Colorado Boulder

Banerjee also works in NOAA’s Chemical Sciences Division. This study was started while she was a Postdoctoral Fellow at Columbia University.

The ozone hole was first discovered in 1985 and has been forming in the atmosphere high over Antarctica every spring. Due to ozone depletion, the air cools down, which strengthens the winds of the polar vortex and has an impact on the winds all the way down to the lowest layer of Earth’s atmosphere. Eventually, as a result of ozone depletion, the dry regions at the edge of the tropics and the midlatitude jet stream have been shifted toward the South Pole.

As per earlier studies, these circulation trends are associated with changes in the weather in the Southern Hemisphere, specifically rainfall over East Africa, South America, and Australia, as well as with variations in ocean currents and salinity.

As part of the Montreal Protocol of 1987, the manufacture of ozone-depleting substances like chlorofluorocarbons (CFCs) was phased out. Starting around 2000, the concentrations of such chemicals in the stratosphere began declining, resulting in the recovery of the ozone hole.

As part of the new study, Banerjee and her colleagues have demonstrated that around the year 2000, the circulation in the Southern Hemisphere also ceased to extend toward the pole—a break or slight reversal of the earlier trends.

The challenge in this study was proving our hypothesis that ozone recovery is in fact driving these atmospheric circulation changes and it isn’t just a coincidence.

Antara Banerjee, Study Lead Author and Visiting Fellow, CIRES, University of Colorado Boulder

The researchers achieved this by employing a two-step statistical method known as detection and attribution: detecting whether specific patterns of wind changes noticed are unlikely to be caused by natural variability alone and, if so, whether the variations could be due to human-induced factors, like emissions of ozone-depleting chemicals and CO2.

With the help of computer simulations, they first concluded that the noticed break in circulation trends could not just be attributed to natural shifts in winds. Then, they isolated the effects of greenhouse gases and ozone separately, demonstrating that while an increase in CO2 emissions has continuously expanded the near-surface circulation (including the jet stream) polewards, only the ozone changes could be attributed to a break in circulation trends.

Before the year 2000, due to both increasing CO2 levels and ozone depletion, the near-surface circulation was expanded poleward. Since 2000, CO2 has constantly pushed this circulation poleward, thus balancing the opposing effect of the ozone recovery.

Identifying the ozone-driven pause in circulation trends in real-world observations confirms, for the first time, what the scientific ozone community has long predicted from theory.

John Fyfe, Study Co-Author and Scientist, Environment and Climate Change Canada

With the continuous increase in CO2 levels and the beginning of ozone recovery, the future is less certain, even for those Southern Hemisphere regions where the weather is influenced by the jet stream, as well as those at the edge of the dry regions.

We term this a ‘pause’ because the poleward circulation trends might resume, stay flat, or reverse,” added Banerjee. “It’s the tug of war between the opposing effects of ozone recovery and rising greenhouse gases that will determine future trends.”

Source: https://cires.colorado.edu/

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Apollo 13’s most famous quotes originated in Hollywood – 680 News

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CAPE CANAVERAL, Fla. — Apollo 13’s best known quotes originated not in space or Mission Control, but in Hollywood.

Their moon-bound spacecraft wrecked by an oxygen tank explosion on April 13, 1970, the astronauts urgently radioed, “Houston, we’ve had a problem here.”

Screenwriters for the 1995 film “Apollo 13? wanted to punch that up. Thus was born “Houston, we have a problem.”

Even more artistic license was taken with NASA flight director Gene Kranz’ mobilizing speech to his team in Houston.

Kranz never declared, “Failure is not an option.”

Ask Kranz what he actually told flight controllers, and he rattles it off without a moment’s hesitation a half-century later.

“I have never lost an American in space, sure as hell aren’t going to lose one now. This crew is coming home. You got to believe it. Your team must believe it. And we must make it happen.”

Kranz said the moviemakers came up with “Failure is not an option.”

Does he wish he’d said it? “No — I’m satisfied with what I said.”

Kranz constantly finds himself setting the record straight — “in fact, every time I speak.”

“I try not to plagiarize,” he said with a laugh.

He did borrow the phrase for the title of his 2000 autobiography.

Director Ron Howard’s film starring Ed Harris as Kranz and Tom Hanks as mission commander Jim Lovell was based on Lovell’s 1994 autobiography, “Lost Moon.” Actors Bill Paxton and Kevin Bacon portrayed Apollo 13 astronauts Fred Haise and Jack Swigert.

___

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

Marcia Dunn, The Associated Press

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'Houston, we've had a problem': Remembering Apollo 13 at 50 – CTV News

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CAPE CANAVERAL, FLA. —
Apollo 13’s astronauts never gave a thought to their mission number as they blasted off for the moon 50 years ago. Even when their oxygen tank ruptured two days later — on April 13.

Jim Lovell and Fred Haise insist they’re not superstitious. They even use 13 in their email addresses.

As mission commander Lovell sees it, he’s incredibly lucky. Not only did he survive NASA’s most harrowing moonshot, he’s around to mark its golden anniversary.

“I’m still alive. As long as I can keep breathing, I’m good,” Lovell, 92, said in an interview with The Associated Press from his Lake Forest, Ill., home.

A half-century later, Apollo 13 is still considered Mission Control’s finest hour.

Lovell calls it “a miraculous recovery.”

Haise, like so many others, regards it as NASA’s most successful failure.

“It was a great mission,” Haise, 86, said. It showed “what can be done if people use their minds and a little ingenuity.”

As the lunar module pilot, Haise would have become the sixth man to walk on the moon, following Lovell onto the dusty gray surface. The oxygen tank explosion robbed them of the moon landing, which would have been NASA’s third, nine months after Apollo 11’s Neil Armstrong and Buzz Aldrin took humanity’s first footsteps on the moon.

Now the coronavirus pandemic has robbed them of their anniversary celebrations. Festivities are on hold, including at Kennedy Space Center in Florida, where the mission began on April 11, 1970, a Saturday just like this year.

That won’t stop Haise, who still lives in Houston, from marking what he calls “boom day” next Monday, as he does every April 13.

Lovell, Haise and Jack Swigert, a last-minute fill-in who died in 1982, were almost to the moon when they heard a bang and felt a shudder. One of two oxygen tanks had burst in the spacecraft’s service module.

The tense words that followed are the stuff of space — and movie — fame.

“OK, Houston, we’ve had a problem here,” radioed Swigert, the command module pilot.

“This is Houston. Say again, please.”

“Houston, we’ve had a problem,” Lovell cut in.

Lovell reported a sudden voltage drop in one of the two main electrical circuits. Within seconds, Houston’s Mission Control saw pressure readings for the damaged oxygen tank plunge to zero. The blast also knocked out two electrical power-generating fuel cells and damaged the third.

As Lovell peered out the window and saw oxygen escaping into the black void, he knew his moon landing was also slipping away. He shoved all emotions aside.

“Not landing on the moon or dying in space are two different things,” Lovell explained, “and so we forgot about landing on the moon. This was one of survival. How do we get home?”

The astronauts were 200,000 miles (322,000 kilometres) from Earth. Getting back alive would require calm, skill and, yes, luck.

“The explosion could not have happened at a better time,” Lovell said.

Much earlier, he said, and the astronauts wouldn’t have had enough electrical power to make it around the moon and slingshot back to Earth for a splashdown. A blast in lunar orbit or, worse still, while Lovell and Haise were on the surface, “that would be the end of it.”

“I think we had some divine help in this flight,” Lovell said.

The aborted mission went from being so humdrum that none of the major TV networks broadcast the astronauts’ show-and-tell minutes before the explosion, to a life-and-death drama gripping the entire world.

As flight director Gene Kranz and his team in Houston raced to come up with a rescue plan, the astronauts kept their cool. It was Lovell’s fourth spaceflight – his second to the moon – and the first and only one for Haise and Swigert.

Dark thoughts “always raced through our minds, but silently. We didn’t talk about that,” Lovell said.

Added Haise: “We never hit the point where there was nothing left to do. So, no, we never got to a point where we said, `Well, we’re going to die.”‘

The White House, less confident, demanded odds. Kranz refused, leaving it to others to put the crew’s chances at 50-50. In his mind, there was no doubt, no room for failure — only success.

“Basically that was the name of the game: I’m going to get them home. My team’s going to get them home. We will get them home,” Kranz recalled.

For the record, Kranz never uttered “failure is not an option.” The line is pure Hollywood, created for the 1995 movie “Apollo 13” starring Ed Harris as Kranz and Tom Hanks as Lovell.

The flight controllers went into crisis mode. They immediately ordered the command module Odyssey shut down to conserve what little power remained, and the astronauts to move into the lunar module Aquarius, now a lifeboat.

One of the low points, Lovell said, was realizing they’d be cramped together in the lander.

“It was designed for two people for two days. We were three people for four days.”

The carbon dioxide overload, from breathing, threatened to kill them.

Engineers scrambled to figure out how to convert the square air-purifying canisters in the dead capsule into round ones that would fit in their temporary home.

Their outside-the-box, seat-of-the-pants solution, using spacecraft scraps, worked. But it was so damp and cold that the astronauts couldn’t sleep. Condensation covered the walls and windows, and the temperature was close to freezing.

Dehydrated and feverish, Haise had the roughest time during the six-day ordeal. Despite the sky-high stress, Haise recalls no cross words among the three test pilots. Even Swigert fit in, despite joining the crew a scant three days before liftoff. He replaced command module pilot Ken Mattingly, who with his crewmates had been exposed to German measles, but unlike them didn’t have immunity.

Rumours swirled that the astronauts had poison pills tucked away in case of a hopeless situation. Lovell dispelled that notion on page one of his 1994 autobiography, “Lost Moon,” the basis for the “Apollo 13? film.

Splashdown day finally arrived April 17, 1970 — with no guarantees.

The astronauts managed to power up their command module, avoiding short circuits but creating a rainfall inside as the spacecraft decelerated in the atmosphere.

The communication blackout lasted 1 1/2 minutes longer than normal. Controllers grew alarmed. Finally, three billowing parachutes appeared above the Pacific. It was only then, Lovell said, that “we knew that we had it made.”

The astronauts had no idea how much their cosmic cliffhanger impacted the world until they reached Honolulu. President Richard Nixon was there to greet them.

“We never dreamed a billion people were following us on television and radio, and reading about us in banner headlines of every newspaper published,” Lovell noted in a NASA history.

The tank explosion later was linked to damage caused by electrical overheating in ground tests.

Apollo 13 “showed teamwork, camaraderie and what NASA was really made of,” said Columbia University’s Mike Massimino, a former shuttle astronaut.

In the decades since, Lovell and his wife, Marilyn, of nearly 68 years have discussed the what-ifs and might-have-beens.

“The outcome of everything is, naturally, that he’s alive,” she said, “and that we’ve had all these years.”

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content,

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NASA Awards Contract to Deliver Science, Tech to Moon Ahead of Human Missions – Space Ref

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Press Release
From: NASA HQ
Posted: Wednesday, April 8, 2020

NASA has selected Masten Space Systems of Mojave, California, to deliver and operate eight payloads – with nine science and technology instruments – to the Moon’s South Pole in 2022, to help lay the foundation for human expeditions to the lunar surface beginning in 2024.

The payloads, which include instruments to assess the composition of the lunar surface, test precision landing technologies, and evaluate the radiation on the Moon, are being delivered under NASA’s Commercial Lunar Payload Services (CLPS) initiative as part of the agency’s Artemis program.

As the country and the world face the challenges of the COVID-19 pandemic, NASA is leveraging virtual presence and communications tools to safely make progress on these important lunar exploration activities, and to award this lunar surface delivery as it was scheduled prior to the pandemic.

“Under our Artemis program, we are going to the Moon with all of America,” said NASA Administrator Jim Bridenstine. “Commercial industry is critical to making our vision for lunar exploration a reality. The science and technology we are sending to the lunar surface ahead of our crewed missions will help us understand the lunar environment better than we ever have before. These CLPS deliveries are on the cutting edge of our work to do great science and support human exploration of the Moon. I’m happy to welcome another of our innovative companies to the group that is ready to start taking our payloads to the Moon as soon as possible.”

The $75.9 million award includes end-to-end services for delivery of the instruments, including payload integration, launch from Earth, landing on the Moon’s surface, and operation for at least 12 days. Masten Space Systems will land these payloads on the Moon with its XL-1 lander.

“The Moon provides great scientific value, and these payloads will advance what we know and help define and improve the science astronauts can do,” said Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate (SMD). “Our commercial Moon delivery efforts are seeking to demonstrate how frequent and affordable access to the lunar surface benefits both science and exploration.”

The payloads that will be delivered have been developed predominantly from the two recent NASA Provided Lunar Payloads (NPLP) and Lunar Surface Instrument and Technology Payloads (LSITP) solicitations.

The nine instruments to be delivered are:

  • Lunar Compact Infrared Imaging System (L-CIRiS) will deploy a radiometer – a device that measures infrared wavelengths of light – to explore the Moon’s surface composition, map its surface temperature distribution, and demonstrate the instrument’s feasibility for future lunar resource utilization activities.
  • Linear Energy Transfer Spectrometer (LETS) is a sensor that will measure the radiation environment on the Moon’s surface. The payload also is being flown on a CLPS flight to the Moon in 2021.
  • Heimdall is a flexible camera system for conducting lunar science on commercial vehicles. This innovation includes a single digital video recorder and four cameras: a wide-angle descent imager, a narrow-angle regolith imager, and two wide-angle panoramic imagers. This camera system is intended to model the properties of the Moon’s regolith – the soil and other material that make up the top layer of the lunar surface – and characterize and map geologic features. Other goals for this instrument include characterizing potential landing or trafficability hazards.
  • MoonRanger is a small robotic rover that weighs less than 30 pounds and will demonstrate communications and mapping technologies. It will demonstrate the ability to move quickly across long distances on the lunar surface with autonomous navigation and without the ability to communicate with Earth in real time. It is a technology that could enable exploration of destinations that are far from lunar landing sites. The MoonRanger will carry the Neutron Spectrometer System, which will measure the concentration of hydrogen in the Moon’s regolith – a possible indication of the existence of buried water.
  • Mass Spectrometer Observing Lunar Operations (MSolo) is a device to measure potentially accessible resources on the Moon’s surface. It will identify gases coming off a lander during touchdown on the lunar surface to help scientists understand what elements are coming from the lunar surface and which ones are introduced by a lander itself.
  • Near-Infrared Volatile Spectrometer System (NIRVSS) is a tool to measure surface composition and temperature. The instrument will characterize the variability of the lunar soils and detect volatiles such as methane, carbon dioxide, ammonia and water.
  • Laser Retroreflector Array (LRA) is a series of eight small mirrors to measure distance and support landing accuracy. It requires no power or communications from the lander and can be detected by future spacecraft orbiting or landing on the Moon.
  • Sample Acquisition, Morphology Filtering, and Probing of Lunar Regolith (SAMPLR) is a robotic arm that will collect samples of lunar regolith and demonstrate the use of a robotic scoop that can filter and isolate particles of different sizes. The sampling technology makes use of a flight spare from the Mars Exploration Rover project.

NASA has contracted with 14 American companies to deliver science and technology to the lunar surface through competed task orders. The agency plans to issue at least two such task orders per year through which the companies can propose to take payloads to the Moon. Under the Artemis program, early commercial deliveries of payloads to the lunar surface missions enable NASA to perform science experiments, test technologies and demonstrate capabilities to further explore the Moon and prepare for human missions. 

“I am very pleased to award our next delivery service task order to Masten Space Systems,” said Steven Clarke, deputy associate administrator for exploration in SMD. “With the first delivery in 2022, we are continuing to execute our strategy of providing two delivery opportunities per year of science investigations and technology demonstration payloads to the lunar surface.”

In May 2019, NASA selected two CLPS providers, Astrobotic and Intuitive Machines, who are each making progress toward sending payloads to the Moon next year. In February, NASA asked the 14 companies to provide proposals to fly the Volatiles Investigating Polar Exploration Rover (VIPER), which will be the first rover on the Moon that will look for and map the distribution of water and other important volatiles at one of the lunar poles. In addition to these deliveries and the delivery to be made by Masten Space Systems, payloads for a fifth lunar delivery are in development, and NASA will soon be initiating a new series of payload acquisitions for targeted science investigations for years to come.

Find more information about the agency’s Commercial Lunar Payload Services project at:

http://www.nasa.gov/clps

Read more about NASA’s Artemis program at:

http://www.nasa.gov/artemis

// end //

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