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The Satellite Images That Show a Decade of Climate Change – Gizmodo

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Decade’s EndDecade’s EndGizmodo, io9, and Earther look back at our passing decade and look ahead at what kind of future awaits us in the next ten years.

The 2010s will be remembered as the decade when we could no longer deny climate change.

I mean, it’s not like any rational person could deny it in the preceding decades, but the past 10 years have seen scientists’ predictions become reality. Our world has entered an unsteady state, one where the things previous generations took for granted—a frozen Arctic, less violent weather—are no more.

While the impacts of the climate crisis are clear to anyone living on Earth, satellites continue to offer the most striking view of the large-scale changes. Orbiting anywhere from about 400 to 500 miles above the Earth’s surface, satellites operated by NASA and the European Space Agency have revolutionized our understanding of the planet. They’ve provided fuel for groundbreaking discoveries about climate change from pole to pole. But you don’t have to have a PhD to look at the imagery being sent back to Earth and see the changes afoot.

With the help of Pierre Markuse, a satellite imagery expert who worked with Sentinel Hub, Earther took a look at a handful of the changes over the past decade that illuminates the ongoing climate crisis.

Baffin Island’s disappearing ice cap

Ice all around the world is melting, and really, we could’ve picked any of the hundreds of disappearing glaciers, ice patches, and Arctic sea ice. But the Barnes Ice Cap on Canadian Arctic’s Baffin Island stands out for a few reasons. For one, the cap is a remnant of some of the Earth’s most ancient ice, the Laurentide Ice Sheet that stretched from Baffin Island as far south as Chicago during the last Ice Age. Momentous research published earlier this year used ancient plants taken at the edges of the cap to show the Arctic hasn’t been this heated in at least 115,000 years.

Despite existing for more than 100,000 years, the rapid Arctic warming of the past decade has taken a noticeable toll on the ice. Imagery from NASA’s Terra satellite shows the ice cap—which differs from a glacier because it sits in place rather than moving—has retreated and grown darker. The darkening of the cap could hasten its demise. While we may have to wait another few centuries for that to happen, the fact that we can see changes over the past decade illustrates we’re already losing history.

The Tubbs Fire remakes California

This has also been the decade of fire for the West as the climate crisis dried out forests and increased the odds of hot weather that can fuel large fires. But California is perhaps the place most synonymous with flames. Five of the largest fires on record for the state occurred this decade. Of the 10 most destructive fires that state has seen, seven occurred this decade (and six in the last three years alone).

The Tubbs Fire ranks second on that list. The October 2017 fire marauded through the North Bay community of Santa Rosa, charring nearly 37,000 acres and destroying 5,636 structures. ESA’s Sentinel satellite captured the immediate aftermath of the fire. But it also shows that two years later, the landscape and community are still recovering. The burn scar is still visible in the hills surrounding Santa Rosa and the neighborhoods most affected are still in early stages of being rebuilt.

When it occurred, the Tubbs Fire was the most destructive fire in state history, but it was bumped to number two just a year later by 2018’s horrific Camp Fire. This year’s fire season was mild by comparison, but that’s largely because utilities that have been responsible for some of the state’s worst fires shut down power to avoid a repeat (which came with a whole host of other issues). That raises questions about where we should build (or rebuild) and what future forest communities should look like.

The big ‘berg that captivated the world

“Superstar” and “iceberg” are not usually synonymous. But the Larsen C iceberg fit the bill. The saga of the ‘berg began in 2016 when cracked formed on the Larsen C ice shelf that sits on the Antarctic Peninsula. The cracks portended a massive iceberg could break away from the floating chunk of ice and reshape the remaining ice.

After a year, the iceberg finally broke away in July 2017. Dubbed A68, the iceberg was about half the size of Jamaica and began a languorous journey out to sea. The open water in front of the new face of the ice shelf became a protected area, and scientists planned a trip into the breach to catch a rare glimpse of what happens when a ‘berg opens up new water. Sea ice, unfortunately, thwarted the trip, but researchers eventually made it there in 2019.

What happens next for the rest of Larsen C is still TBD. The neighboring Larsen A and B ice shelves collapsed specularly in 1995 and 2002, respectively. The calving event was massive but largely due to natural forces, though warming oceans could now cut away at the weakened ice shelf. As for A68? The trillion-ton iceberg is still swirling along the coast of the Antarctic Peninsula on a slow track north. Once in warmer waters, it will eventually meet its watery demise.

The Aral Sea continues its disappearing act

The Aral Sea began to disappear long before the 2010s, but that doesn’t make its continued decline any more shocking. The inland sea was once the fourth-largest lake in the world. A 1960s Soviet irrigation project cut off the two rivers that were its lifeblood, and what was once the fourth-largest lake in the world has been shriveling in the decade since. The climate crisis has contributed to the sea’s transition into a desert, which, in turn, has further altered the region’s climate to an even harsher state.

The 2010s weren’t kind to the sea. Imagery from the start of the decade shows the Aral Sea had a bit of brackish water sitting in the eastern portion of the basin. But by 2014, the only bit of the sea remaining is a sliver on the west side of the lake. While the northern reaches of the sea have bounced back slightly thanks to a dam that has helped build up water levels, the larger southern portion continues to suffer.

Coastlines recede in the Arctic

Drew Point, Alaska, is about 70 miles as the crow flies from Utqiagvik, the northernmost city in the U.S. The pedestrian chunk of coastline isn’t anyone’s idea of an ideal place for a beach vacation. It’s cold, winter brings 24-hour darkness, polar bears are a concern. But the biggest issue is that it’s rapidly eroding.

Battering storms coupled with disappearing sea ice mean house-sized chunks of permafrost and tundra have fallen into the sea. The coastline has recently receded by up to 50 feet per year. The erosion can release stores of greenhouse gases the permafrost holds. And the loss of coast in this remote location is indicative of struggles around the Arctic. The Alaskan village of Kivalina is being forced to relocate due to erosion, making residents some of the first climate refugees in America. And other communities could follow suit as sea levels rise and continue their assault on the coasts.

Solar flourishes in the desert

A time-lapse of the Tengger Solar Park as it grows over the course of the 2010s.
Gif: Pierre Markuse (Sentinel Hub)

Hey, it’s not all bad news (just mostly). Renewables are part of the solution to the climate crisis. While the world has failed to tilt the balance of the energy system toward them in the 2010s, we’ve at least made some headway. The Tengger Solar Park is the world’s largest solar farm, covering more than 16 square miles of China’s Ningxia province. The solar plants there have the capacity to generate 1.5 gigawatts of electricity, enough to power roughly 380,000 American homes.

In China and globally, wind and solar have been growing by leaps and bounds over the course of the 2010s. That’s the good news. The downside is, they still account for just 10 percent of global energy generation, a level they’ve stood at for years as energy demand continues to outpace the amount of renewables being installed. The world will have to draw down carbon emissions (and not just from electricity) nearly 8 percent per year in the 2020s to avert catastrophic climate change. Solar parks like these will be just the tip of the iceberg if we are to succeed.

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These Tiny, Little-Winged Dinosaurs Were Probably Worse at Flying Than Chickens – ScienceAlert

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The discovery of two small dinosaurs with bat-like wings a few years ago was a palaeontologist’s dream. Just how flight evolved in birds is something we’re still trying to nail down, and looking at this early evolution of bat-like wings in dinosaurs could give us a clue.  

But a team of researchers has now pointed out that just because you have wings, it doesn’t necessarily mean you’re actually any good at flying.

Yi qi and Ambopteryx longibrachium are two species of theropod dinosaurs that lived around 160 million years ago, both of which had unusually elongated fingers, and a skin membrane stretching between them, similar to a bat’s wing.

This is an entirely different kind of wing to the one theropod dinosaurs evolved to fly with – the dinosaurs that eventually became birds. And, unlike them, after only a few million years, Yi and Ambopteryx became extinct, which is the first hint that these unusual wings could not match those birds-to-be. 

However, weird wings on extinct critters mean it’s likely multiple types of wings (and therefore flight) evolved over the years, and that Yi and Ambopteryx’s attempts were not the winning strategy.

But before you can write off Yi and Ambopteryx as complete evolutionary flight failures, you have to know how good (or bad, as the case may be) the two species were at flight.

In 2015, when Yi was found, that team of researchers suggested that the size of its wings and other flight characteristics could mean it was a gliding creature – however it’s unlike any other glider we know of, and its centre of mass might have made even gliding difficult. We just weren’t sure.

A new study, by researchers in the US and China, has now looked into the flight potential of Yi and Ambopteryx in a lot more detail, and come to the conclusion that they really weren’t good at getting their little feet off the trees they lived in.

“Using laser-stimulated fluorescence imaging, we re-evaluate their anatomy and perform aerodynamic calculations covering flight potential, other wing-based behaviours, and gliding capabilities,” the team writes.

“We find that Yi and Ambopteryx were likely arboreal, highly unlikely to have any form of powered flight, and had significant deficiencies in flapping-based locomotion and limited gliding abilities.”

The team’s analysis of the fossils (Yi pictured below) was able to pick up tiny details in soft-tissue that you can’t see with normal light.

Fossil of Yi qi. Look how fluffy it is! (kmkmks/Flickr/CC BY SA 2.0)

Then the team modelled how the dinosaurs might have flown, adjusting for things such as weight, wingspan, and muscle placement (all stuff we can’t tell just from the fossils).

The results were… underwhelming.

“They really can’t do powered flight,” says first author, biologist Thomas Dececchi from Mount Marty University.

“You have to give them extremely generous assumptions in how they can flap their wings. You basically have to model them as the biggest bat, make them the lightest weight, make them flap as fast as a really fast bird, and give them muscles higher than they were likely to have had to cross that threshold. They could glide, but even their gliding wasn’t great.”

gr1Soft-tissue map of Yi qi. (Dececchi et al., iScience, 2020)

So, according to Dececchi and his team’s model, we’re looking at flying capabilities considerably worse than a chicken, perhaps worse than the flightless New Zealand parrot, the kakapo, which is also mostly limited to gliding from trees, but can at least flap to control descent.

But although it’s a bit sad for the Yi and Ambopteryx, it’s good news for us – the findings give even more evidence that dinosaurs evolved flight (or at least tried to) multiple times.

As the team points out, considering all the types of bats, gliders, flying squirrels, and other gliding or flying mammals, maybe it shouldn’t be a surprise.

“We propose that this clade was an independent colonisation of the aerial realm for non-avialan theropods. If true, this would represent at least two, but more likely three or more attempts at flight (both powered and gliding) by small pennaraptoran theropods during the Mesozoic,” the team writes in their paper.

“Given the large number of independent occurrences of gliding flight within crown mammals, this should perhaps be unsurprising, but it does create a more complex picture of the aerial ecosystem.”

Seems like some things don’t change much, even in a hundred million years.

The research has been published in iScience.

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NASA Spacecraft Osiris-Rex Extracts Samples From Asteroid Bennu, a First for US – The Daily Beast

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NASA Spacecraft Osiris-Rex Extracts Samples From Asteroid Bennu, a First for U.S.

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'Weird bat-winged' dinosaurs glided through treetops in attempt at flight: study – CTV News

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TORONTO —
A new study investigating the flight capabilities of two tiny dinosaurs with thin, bat-like wings is shedding light on the evolution of avian flight itself — an evolution that, it turns out, had a lot of dead ends and false starts along the way.

Published in the journal iScience earlier this week, the study looked at Yi and Ambopteryx, two dinosaurs who lived around 160 million years ago in the Late Jurassic era of China. Both were believed to have the potential for flight due to the thin membranes stretched between their arms and their bodies.

However, when researchers applied mathematical modelling to these prehistoric creatures, they found that they were nowhere near capable of propelling themselves through the air like birds, and instead would’ve used their small wings only to glide.

“We know some dinosaurs could fly before they evolved into birds,” Hans Larsson, a professor at McGill University and Director of McGill’s Redpath Museum, said in a press release. “What this shows us is that at least one lineage of dinosaurs experimented with a completely different mode of aerial locomotion.”

A ‘WEIRD BAT-WINGED’ PAIR

Researchers scanned fossils of Yi and Ambopteryx with lasers to pick out where the soft tissue would fall on their wings, details that couldn’t be seen under regular light.

Then they reconstructed the dinosaurs’ morphology with computer modelling to see whether they could power themselves to flight, whether by leaping from trees or from the ground. They also changed important variables like wingspan and body weight to assess different scenarios on how they might have flown.

In order to flap their wings with enough force to support their own body, the dinosaurs would’ve needed strong pectoral muscles, which were absent. Ambopteryx could only take off in flight at the lowest estimated body size and highest estimated power level, and Yi could not obtain any lift-off except at body weights researchers said were likely too small to be accurate. In almost all scenarios, the dinosaurs could not get off the ground under their own power.

Even with a running start to help them, the minimum take off speed for Yi would be between 1.1 and three times the maximum possible speed Yi would have been capable of. For Ambopteryx, the minimum take-off speed was even more out of reach, needing to be at least 2.3 to four times their top sprinting speed.

The two dinosaurs were capable of gliding if they leaped from trees — but not well. The research found that compared to other dinosaurs capable of gliding or flying, these two “show poorly developed gliding abilities.”

Both Yi and Ambopteryx would have to launch from higher points in trees at higher speeds than other creatures that glide, and they would be less precise when they landed.

They are thought to have spent most of their lives in trees, eating insects, seeds and plants.

AVIALANS AND THE EVOLUTION OF FLIGHT

Many modern creatures can glide, but only pterosaurs, bats and birds developed the structures necessary to fly by flapping their wings.

It’s well known that modern day birds are descendants of dinosaurs, but this new research adds a complication to the predominant theory of how avian flight came about.

The majority of dinosaurs with flying capabilities — called avialans — have had very similar characteristics and body types, and different families of dinosaurs who have evolved towards flight have started as ground-dwelling creatures and gone through similar body changes — such as a reduction in body size, getting an increased shoulder mobility and developing feathers on their four limbs — before gaining the ability to fly.

This has told a reasonably streamlined tale about the evolution of flight from dinosaurs to birds for the most part, the study explained.

But Yi and Ambopteryx are outliers, showing that dinosaur flight went through some bumps on the road.

Both are therapods, a categorization of carnivorous dinosaurs with hollow bones that includes the T-rex and birds, but they’re also part of a little-understood group called Scansoriopterygidae, which are climbing and gliding dinosaurs.

It’s been posited before that scansoriopterygids could represent an interim stage before avialans, an early model of bird flight that then evolved to support more powered flying. But researchers say this was far more likely an independent attempt at flight, a “failed experimental lineage of early arboreal gliders” unconnected to the evolution of avialan flight.

“Given the large number of independent occurrences of gliding flight within crown mammals, this should perhaps be unsurprising, but it does create a more complex picture of the aerial ecosystem,” the study stated.

“We used to think of birds evolving as a linear trend from their ground-dwelling dinosaur ancestry,” Larsson said in the release.

“We can [now] revise this textbook scenario to one that had an explosive diversity of experimentation, with dinosaurs evolving powered flight several times independently from birds, many having fully feathered wings but with bodies too heavy or wings too small to have gotten off the ground, and now, a weird bat-winged group of dinosaurs that were not only the first arboreal dinosaurs, but ones that glided.”

He added that he feels like researchers are “still just scratching the surface,” of dinosaur biodiversity.

Yi, Ambopteryx and others scansoriopterygids had a short-lived existence, unable to compete with the mammalian gliders and avialan fliers that were evolving around them.

Both dinosaurs went extinct after only a few million years, according to the press release.

“Once birds got into the air, these two species were so poorly capable of being in the air that they just got squeezed out,” lead author Thomas Dececchi, an assistant professor of biology at Mount Marty University, said in the release. “Maybe you can survive a few million years underperforming, but you have predators from the top, competition from the bottom, and even some small mammals adding into that, squeezing them out until they disappeared.”

Gliding isn’t an efficient way to get around, as you have to climb to a great height first to travel any sort of distance, he explained.

“It’s not efficient, but it can be used as an escape hatch. It’s not a great thing to do, but sometimes it’s a choice between losing a bit of energy and being eaten. Once they were put under pressure, they just lost their space.

“They couldn’t win on the ground,” he said. “They couldn’t win in the air. They were done.”

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