You probably know at least a little bit about ocean circulation around the world, also known as currents. In fact, you may have felt smaller currents yourself on a day at the beach.



But have you heard bout the "great global ocean conveyor belt," which is a vast network of currents that constantly moves water around the entire planet?



This massive system helps distribute heat around the world, influencing everything from temperatures to rainfall. Unfortunately, it's slowing down and on the verge of total collapse.



Scientists have been studying this phenomenon, and according to recent research published in <a href="https://www.nature.com/articles/s41561-024-01568-1" target="_blank" rel="noreferrer noopener">Nature Geoscience</a>, it's a bigger deal than we thought. 



<h2 class="wp-block-heading" id="h-ocean-circulation-and-the-amoc">Ocean circulation and the AMOC?</h2>



The Atlantic Meridional Overturning Circulation, or AMOC, is like a massive ocean conveyor belt that moves warm and cold water around the <a href="https://www.earth.com/news/why-the-atlantic-ocean-may-ultimately-vanish/" target="_blank" rel="noreferrer noopener">Atlantic Ocean</a>. 



It starts in the Gulf of Mexico, where warm, salty water flows northward along the eastern coast of the United States and across the Atlantic towards Europe. 



As this warm water reaches the North Atlantic, it cools down, becomes denser, and sinks deep into the ocean. 



This sinking process pulls more warm water north to replace it, creating a continuous loop that helps <a href="https://www.earth.com/news/collapse-of-major-ocean-system-would-cause-weather-chaos/" target="_blank" rel="noreferrer noopener">regulate the climate</a> by distributing heat across the planet. 



Thanks to the AMOC, regions like Western Europe enjoy milder winters than they would otherwise.



Humans rely on the AMOC in several important ways. By regulating global temperatures, it helps maintain stable weather patterns, which are crucial for agriculture, ecosystems, and our daily lives. 



Researchers point out that the Atlantic Meridional Overturning Circulation (AMOC) is now weaker than at any other time in the past 1,000 years.



The research team from several leading universities explains that global warming is behind this slowdown. 



Their new modeling suggests that meltwater from the <a href="https://www.earth.com/news/greenlands-melting-icebergs-may-not-be-threat-to-ocean-currents-amoc/" target="_blank" rel="noreferrer noopener">Greenland ice sheet</a> and Canadian glaciers could be the missing piece of the puzzle.



<h2 class="wp-block-heading" id="h-why-should-we-care-about-this">Why should we care about this?</h2>



"Our results show the Atlantic overturning circulation is likely to become a third weaker than it was 70 years ago at 2°C of global warming," says the research team. 



"This would bring big changes to the <a href="https://www.earth.com/news/the-arctic-is-melting-fast-but-a-slowing-ocean-current-could-help/" target="_blank" rel="noreferrer noopener">climate and ecosystems</a>, including faster warming in the southern hemisphere, harsher winters in Europe, and weakening of the northern hemisphere's tropical monsoons."



Think about that for a second. A weaker ocean current could mean colder winters in Europe and shifts in rainfall patterns that affect millions of people. It's not just about the ocean; <a href="https://www.earth.com/news/disastrous-climate-changes-of-the-last-ice-age-could-happen-again/" target="_blank" rel="noreferrer noopener">it's about our daily lives</a>.



<h2 class="wp-block-heading" id="h-meltwater-and-ocean-circulation">Meltwater and ocean circulation</h2>



The Earth has already warmed 1.5ºC since the industrial revolution. And get this: the Arctic has been heating up nearly four times faster than the rest of the planet. 



All that heat is melting Arctic sea ice, glaciers, and the Greenland ice sheet.



"Since 2002, Greenland lost 5,900 billion tons (gigatons) of ice," notes the research team. "To put that into perspective, imagine if the entire state of Texas was covered in ice 26 feet thick."



All this fresh meltwater flowing into the subarctic ocean is lighter than salty seawater, so it doesn't sink as much. 



That messes with the southward flow of deep, cold waters from the Atlantic and <a href="https://www.earth.com/news/climate-change-will-impact-the-gulf-stream-more-than-we-thought/" target="_blank" rel="noreferrer noopener">weakens the Gulf Stream</a> -- the same current that gives Britain its mild winters.



<h2 class="wp-block-heading" id="h-ripple-effects-around-the-globe">Ripple effects around the globe</h2>



So, what's the big deal with the Gulf Stream slowing down? Well, for starters, Europe could face harsher winters. 



<a href="https://www.earth.com/news/climate-paradox-ocean-current-collapse-could-plunge-europe-into-cold/" target="_blank" rel="noreferrer noopener">Places like Britain</a> might start feeling more like their chilly counterparts at the same latitude, such as parts of Canada.



<figure class="wp-block-image aligncenter size-full is-resized"><a href="https://www.earth.com/wp-content/uploads/2024/11/Atlantic-Meridional-Overturning-Circulation_AMOC_collapsing_Nature-Geoscience_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/11/Atlantic-Meridional-Overturning-Circulation_AMOC_collapsing_Nature-Geoscience_1s.webp" alt="The addition of meltwater in the North Atlantic leads to localised cooling in the subpolar North Atlantic and warming in the South Atlantic. Credit: Nature Geoscience (2024)." class="wp-image-1951410" style="width:300px;height:auto"/></a><figcaption class="wp-element-caption">The addition of meltwater in the North Atlantic leads to localised cooling in the subpolar North Atlantic and warming in the South Atlantic. Credit: Nature Geoscience (2024).</figcaption></figure>



"Our new research shows meltwater from the Greenland ice sheet and Arctic glaciers in Canada is the missing piece in the climate puzzle," the researchers explain. 



When they included this meltwater in their simulations, the slowing of the oceanic circulation made sense.



The study confirms that the Atlantic overturning circulation has been slowing down since the mid-20th century. It also gives us a sneak peek into <a href="https://www.earth.com/news/atlantic-and-arctic-mixing-is-crucial-for-earths-climate-stability/" target="_blank" rel="noreferrer noopener">what's coming next</a>.



<h2 class="wp-block-heading" id="h-northern-and-southern-oceans-connected">Northern and Southern oceans connected</h2>



"Our new research also shows the North and South Atlantic oceans are more connected than previously thought," the team states. 



Changes in one part of the ocean can quickly affect distant regions. When the oceanic circulation is strong, it transfers a lot of heat to the <a href="https://www.earth.com/news/antarctic-warming-triggers-rising-north-atlantic-sea-levels/" target="_blank" rel="noreferrer noopener">North Atlantic</a>. 



But when it weakens, the surface of the ocean south of Greenland doesn't warm up as much, leading to what's called a "warming hole." Meanwhile, the South Atlantic ends up storing more heat and salt.



<h2 class="wp-block-heading" id="h-time-is-not-on-our-side">Time is not on our side</h2>



"Our simulations show changes in the far North Atlantic are felt in the South Atlantic Ocean in less than two decades," the researchers reveal. This means the effects of the slowdown are spreading faster than we thought.



Climate projections have suggested the Atlantic overturning circulation will weaken by about 30% by 2060. But hold on -- that's without considering all that extra meltwater.



"The Greenland ice sheet will continue melting over the coming century, possibly raising global sea level by about 4 inches," the study notes. 



"If this additional meltwater is included in climate projections, the overturning circulation will weaken faster. It could be 30% weaker by 2040. That's 20 years earlier than initially projected."



<h2 class="wp-block-heading" id="h-what-can-we-do">What can we do?</h2>



Such a rapid decrease in the overturning circulation will shake things up. 



Europe might see colder winters, the northern tropics could get drier, and places like the southern United States might experience warmer, wetter summers.



"Our climate has changed dramatically over the past 20 years," the researchers warn. "More rapid melting of the ice sheets will accelerate further disruption of the climate system."



So, what does this all mean for us? It means we have even less time to get our act together. Reducing emissions isn't just a good idea -- it's crucial.



Our planet's systems are interconnected in ways we're only beginning to understand. If we want to keep things from getting worse, we need to act now. Every little bit counts, and the clock is ticking.



The full study was published in the journal <a href="https://www.nature.com/articles/s41561-024-01568-1" target="_blank" rel="noreferrer noopener">Nature Geoscience</a>.



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Collapse of Earth's main ocean water circulation system is already happening

You probably know at least a little bit about ocean circulation around the world, also known as currents. In fact, you may have felt smaller currents yourself on a day at the beach. But have you heard bout the "great global ocean conveyor belt," which is a vast network of currents that constantly moves water around the entire planet? This massive system helps distribute heat around the world, influencing everything from temperatures to rainfall. Unfortunately, it's slowing down and on the verge of total collapse. Scientists have...

There are only two northern white rhinos left in the world – Najin and Fatu, two females, both unable to carry a calf. But there’s hope for the species: on Aug. 22, scientists were successful in harvesting eggs from the pair.

The eggs were immediately sent to Italy, where researchers have attempted to fertilize them with cryogenically frozen sperm from four deceased male members of the species.

“We were able to harvest a total of 10 oocytes – five from Najin and five from Fatu – showing that both females can still provide eggs and thus help to save these magnificent creatures,” said Dr. Thomas Hildebrandt from the <a href="http://www.izw-berlin.de/welcome.html">Leibniz Institute for Zoo &amp; Wildlife Research</a>. “Both the technique and the equipment had to be developed entirely from scratch.”

Any resulting embryos will be frozen until southern white rhino surrogates can be found. 

The new procedure brings hope for the species that has been functionally extinct since March 2018, when the last male northern white rhino died.

“We are delighted that this partnership gets us one step closer to prevent extinction of the northern white rhinos,” John Waweru, director general of the <a href="http://www.kws.go.ke/">Kenya Wildlife Service</a>, told the <a href="http://www.dailymail.co.uk/">Daily Mail</a>. “This is particularly touching given the heartbreaking death of Sudan, the last male, who died of old age last year in Kenya.”

There are still challenges ahead, even if the in vitro fertilization goes well. Harvesting eggs from the two females is limited to three times per year; any more would risk their health. And working from a pool of two females and four males could cause a major genetic bottleneck in the species. 

However, scientists do have access to frozen tissues from other northern white rhinos. The group <a href="https://www.facebook.com/biorescueproject/">BioRescue</a> is hoping to create artificial sex cells using those genomes to increase the diversity of rhino embryos in the future. 

Researchers are hoping to re-introduce the northern white rhinos – one of five rhino species – back into their natural habitats. But poachers still pose a major danger; it was poaching for ingredients for traditional Chinese medicine and dagger handles in Yemen that reduced the northern white rhino numbers so drastically, the Daily Mail reported. 

—

By Kyla Cathey, <a href="https://www.earth.com/">Earth.com</a> staff writer

Harvesting eggs of last northern white rhinos may save species

There are only two northern white rhinos left in the...

<a href="http://www.earth.com/news/flame-retardants-hyperthyroidism-cats/">Flame retardants</a> are used in thousands of common products to help prevent fire-related injuries and deaths. However, these chemicals are thought to be threatening to the environment as well as to human health. Organohalogens, which are derived from petroleum, are of particular concern. 

In a groundbreaking new study, experts have found a way to produce flame retardants from natural plant compounds that have the potential to be much safer and eco-friendly.

"The best flame-retardant chemicals have been organohalogen compounds, particularly brominated aromatics," said Bob Howell, who is the project's principal investigator. "The problem is, when you throw items away, and they go into a landfill, these substances can leach into the environment."

Most organohalogen flame retardants are very stable and cannot be degraded, which means that they can persist in the environment for many years. These chemicals are also sometimes released from household items, such as electronics, and are collected in the dust. While the health effects of exposure are largely unknown, many studies indicate that flame retardants are harmful.

"A number of flame retardants are no longer available because of toxicity concerns, so there is a real need to find new materials that, one, are nontoxic and don't persist, and two, don't rely upon petroleum," said Howell. His team set out to identify compounds from plants that could easily be converted into flame retardants by adding phosphorus atoms, which are known to quench flames. 

"We're making compounds that are based on renewable biosources. Very often they are nontoxic; some are even food ingredients. And they're biodegradable - organisms are accustomed to digesting them," explained Howell.

In one test, the researchers demonstrated that their new flame retardants could strongly reduce the peak heat release rate of the epoxy resin, which reflects the intensity of the flame and how quickly it is going to spread. The plant-derived substances performed as well as many organohalogen flame retardants. 

"As a matter of fact, they may be better," said Howell. "Because gallic acid has three hydroxyl groups within the same molecule that can be converted to phosphorous esters, you don't have to use as much of the additive, which reduces cost."

The research team has not yet tested the toxicity of the compounds, but Howell said that other groups have conducted such tests on similar substances. "In general, phosphorous compounds are much less harmful than the corresponding organohalogens." 

Furthermore, the substances obtained from plants are not as volatile and are less likely to migrate from items into household dust. Howell hopes that the new flame retardants will attract the attention of a company that could help to get them on the market.

The research was presented at a meeting of the <a href="https://www.acs.org/">American Chemical Society</a>. 

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: Yoseph Getachew

Scientists are creating safer flame retardants using plants

Flame retardants are used in thousands of common products to...

Since <a href="https://www.earth.com/news/decriminalizing-medicinal-marijuana/">recreational marijuana</a> was first legalized in Washington and Colorado in 2012, edibles have become a huge part of the cannabis industry. 

Edibles are foods infused with cannabis, and these days you can find everything from gummy bears to cookies to chocolate bars that contain marijuana at dispensaries. 

These cannabinoid-infused treats have flooded the market, but a new study has found that components in chocolate are leading to inaccurate potency test results. 

Edible manufacturers must adhere to strict labeling and potency standards. 

That’s where testing labs come in. David Dawson, a researcher at <a href="http://www.cwanalytical.com/">CW Analytical Laboratories</a>, a cannabis testing lab in California, and his team noticed variations while testing chocolate edibles. 

“My research focuses on cannabis potency testing because of the high stakes associated with it,” said Dawson. “If an edible cannabis product tests 10% below the amount on the label, California law states that is must be relabeled, with considerable time and expense. But it’s even worse if a product tests 10% or more above the labeled amount -- then the entire batch must be destroyed.”

Chocolate edibles are extremely common, and the researchers tested the potency of differently prepared samples. 

The researchers experimented with the amounts of chocolate, the type of chocolate, and the concentrations of Δ9-tetrahydrocannabinol, the major psychoactive component of cannabis. 

“When we had less cannabis-infused chocolate in the sample vial, say 1 gram, we got higher THC potencies and more precise values than when we had 2 grams of the same infused chocolate in the vial,” said Dawson. “This goes against what I would consider basic statistical representation of samples, where one would assume that the more sample you have, the more representative it is of the whole.” 

Chocolate contains a component that is leading to inaccurate results, and the researchers say that this component is suppressing the signal for Δ9-tetrahydrocannabinol. 

“Simply changing how much sample is in the vial could determine whether a sample passes or fails, which could have a huge impact on the producer of the chocolate bars, as well as the customer who might be under- or overdosing because of this weird quirk of matrix effects,” said Dawson. 

The researchers have not pinned down exactly what is hindering the potency tests, but it likely has something to do with the fat content in chocolate as Δ9-tetrahydrocannabinol is fat-soluble. 

The findings will be presented at the <a href="https://www.acs.org/">American Chemical Society </a>(ACS) Fall 2019 National Meeting &amp; Exposition taking place this week through Thursday. 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com </a>Staff Writer 

Image Credit: Kevin Kerr

Testing for cannabis potency is problematic in chocolate edibles

Since recreational marijuana was first legalized in Washington and Colorado...

As early humans evolved from their ancient primate ancestors, a helpful genetic mutation arose that created immunity to the simian immunodeficiency virus (SIV), a virus that still plagues primate groups today. 

While this mutation stopped the virus from crossing over to infect humans, eventually the virus found a workaround and SIV evolved to give rise to the <a href="https://www.earth.com/news/drug-treatment-eliminates-hiv-transmission/">human immunodeficiency virus </a>(HIV) which began the AIDS pandemic. 

In a new study, researchers from the <a href="https://www.berkeley.edu/">University of California, Berkley</a> have unlocked the inner workings of how this mutation blocked the SIV virus and how the virus eventually came to infect humans. 

An estimated 38 million people worldwide were living with HIV as of 2018, according to the <a href="https://www.who.int/gho/hiv/en/">World Health Organization</a>, and since the start of the epidemic, 32 million people have died of HIV. 

Before the rise of HIV, early humans developed a mutation in the cells that stopped SIV from hacking the cell’s machinery and making thousands of copies of itself. 

The researchers found that the key was that the mutation disrupted SIV proteins from binding to human proteins. 

“The binding site involved is structurally very complex, so essentially it is not possible to adapt to it once the tight binding is lost. The virus had to invent a completely different way to do the same thing, which took a long time in evolution,” said James Hurley, a co-author of the study. “This conferred an advantage on our prehistoric ancestors: From chimps on down, every primate was susceptible to SIV, but humans were immune.” 

Cryo-electron microscopy was used to analyze the structure of SIV proteins. 

Both SIV and HIV are lentiviruses that take over a host cell, forcing the cell to make copies of the virus, and sending these copies (virions) to infect other cells. 

[caption id="attachment_1876942" align="aligncenter" width="650"]<a href="https://www.earth.com/wp-content/uploads/2019/08/graphic.jpg"><img class="wp-image-1876942" src="https://www.earth.com/wp-content/uploads/2019/08/graphic.jpg" alt="" width="650" height="464" /></a> Image Credit: UC Berkeley image by Cosmo Buffalo[/caption]

The virus wraps its DNA around a piece of the host cell’s membrane to make copies. The cell sheds this piece, and the virus is safely cocooned in a bubble until it finds another cell to infect. 

Typically the immune system would recognize a virus and infection and destroy the entire cell, but SIV found a way to fight these natural defenses. 

SIV virions staple themselves to the cell membrane with something called tetherin. A protein called Nef ramps up the cell’s recycling system forcing the cell to go into overdrive and shed tetherin, whether it’s connected to a virus or not. This allows copies to be safely ejected from the cell. 

Humans developed a mutation which loosened the binding between Nef and the cell proteins and kept the tetherin firmly in place, preventing copies from infecting other cells. 

Eventually, SIV found a workaround, a second protein to wedge in between the proteins and make copies once again. 

“There were probably many crossovers into humans that failed, but eventually, some hunter in Africa, perhaps in the course of butchering a chimp, was exposed to the blood, and the virus then acquired an additional mutation, a small step that turned SIV into HIV,” said Hurley.

The study provides a detailed overview of how early humans evolved a mutation against SIV and the thousands of years it took for SIV to adopt a new strategy and infect human hosts. 

“The main importance for this paper is that it tells us what was one of the last major barriers before the crossover to humans happened,” said Hurley. “The current paper is an archeological look at how this

The researchers published their findings in the journal Cell Host and Microbe.

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette,</a> <a href="https://www.earth.com/">Earth.com </a>Staff Writer 

Main Image Credit: Shutterstock/monofaction

Early humans were once immune to immunodeficiency viruses

As early humans evolved from their ancient primate ancestors, a...

Stegosaurus is one of those iconic dinosaurs, following in the same fossilized footprints as Tyrannosaurus Rex and Triceratops. With its impressive rows of bony plates on its back and <a href="https://www.earth.com/news/animals-tails-weapons/">spiky tail</a>, it’s not hard to see why the plant-eating stegosaurus is so popular among dinosaur lovers. 

In a new discovery, paleontologists have identified a new species of stegosaurus, and it’s the oldest of its kind ever found. The species was described from fossils excavated in Middle Atlas mountains in Morocco. 

The discovery shows that the stegosaurus is older and had a much wider geographic range than previously realized. 

A few vertebrae and an upper arm bone are all that were found, but a team of paleontologists led by Susannah Maidment from the <a href="https://www.nhm.ac.uk/">Natural History Museum</a> in London was able to determine that the bones were about 168 million years old and the specimen belonged to an entirely new species and genus. 

The researchers called the new species Adratiklit boulahfa which means “mountain lizard” in the Berber language. 

“The discovery of A. boulahfa is particularly exciting as we have dated it to the Middle Jurassic,” Maidment said. “Most known stegosaurs date from later in the Jurassic Period, making this the oldest definite stegosaur described and helping to increase our understanding of the evolution of this group of dinosaurs.”

Adratiklit boulahfa is the first stegosaurus discovered in North Africa. Both the specimen’s location and age are of great interest to the scientific community, and the find could help inform our understanding of not only stegosaurus but what geographic formations allowed the dinosaurs to inhabit such a wide range. 

The researchers published their findings in the journal <a href="https://www.sciencedirect.com/science/article/abs/pii/S1342937X19302217">Gondwana Research.</a>

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer 

Main Image Credit: Shutterstock/Daniel Eskridge

Stegosaurus fossil may be the oldest ever discovered

Stegosaurus is one of those iconic dinosaurs, following in the...

Scientists discovered the first planet outside of our solar system in 1992, and today more than 4,000 <a href="http://www.earth.com/news/exoplanet-proxima-centauri-life/">exoplanets</a> have been confirmed. In a new study, researchers have found that some of these exoplanets may have conditions that are even more well-suited to host life than our own planet.

"This is a surprising conclusion," said Dr. Stephanie Olson, who led the investigation, "It shows us that conditions on some exoplanets with favorable ocean circulation patterns could be better suited to support life that is more abundant or more active than life on Earth."

Because it is impossible to reach such distant planets with space probes, scientists are working with remote sensing tools like telescopes to explore the conditions on various exoplanets, and sophisticated models must be used to interpret these remote observations. Dr. Olson's team used ROCKE-3D software, which was developed by NASA to simulate the climates and ocean habitats of different types of exoplanets.

"NASA's search for life in the Universe is focused on so-called habitable zone planets, which are worlds that have the potential for liquid water oceans. But not all oceans are equally hospitable - and some oceans will be better places to live than others due to their global circulation patterns," said Dr. Olson.

"Our work has been aimed at identifying the exoplanet oceans which have the greatest capacity to host globally abundant and active life. Life in Earth's oceans depends on upwelling (upward flow) which returns nutrients from the dark depths of the ocean to the sunlit portions of the ocean where photosynthetic life lives. More upwelling means more nutrient resupply, which means more biological activity. These are the conditions we need to look for on exoplanets."

[caption id="attachment_1876927" align="aligncenter" width="650"]<a href="https://www.earth.com/wp-content/uploads/2019/08/TRAPPIST-1-planetary-system.jpg"><img class="wp-image-1876927" src="https://www.earth.com/wp-content/uploads/2019/08/TRAPPIST-1-planetary-system.jpg" alt="" width="650" height="325" /></a> Artist's concept shows what the TRAPPIST-1 planetary system may look like. Image Credit: NASA/JPL-Caltech[/caption]

After modeling a variety of exoplanets with potential, the experts were able to define the types of exoplanets which stand the best chance of sustaining life.

"We have used an ocean circulation model to identify which planets will have the most efficient upwelling and thus offer particularly hospitable oceans," said Dr. Olson. "We found that higher atmospheric density, slower rotation rates, and the presence of continents all yield higher upwelling rates. A further implication is that Earth might not be optimally habitable - and life elsewhere may enjoy a planet that is even more hospitable than our own."

"There will always be limitations to our technology, so life is almost certainly more common than 'detectable' life. This means that in our search for life in the Universe, we should target the subset of habitable planets that will be most favorable to large, globally active biospheres because those are the planets where life will be easiest to detect - and where non-detections will be most meaningful."

The research was presented by Dr. Olson at the 2019 meeting of the Goldschmidt Geochemistry Congress in Barcelona.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA/JPL-Caltech

Some exoplanets may have better conditions for life than our own planet

Scientists discovered the first planet outside of our solar system...

How did Earth finally produced enough oxygen to escape the ‘boring billion’?. For roughly half of our planet’s 4.6 billion year lifetime, its atmosphere was made up of only carbon dioxide and nitrogen – not exactly a friendly place to exist if you happen to be an oxygen-consuming life form. 

Luckily for us, <a href="http://www.earth.com/news/increases-oxygen-levels-dinosaurs/">oxygen</a> started to come into the picture when cyanobacteria – also known as blue-green algae – began producing the first oxygen through the enzyme nitrogenase, which can be traced back to the universal common ancestor of all cells over four billion years ago.

This oxygen-producing process began the Great Oxidation Event, and while that sounds like an ideal band name, the years that followed were less exciting than its title might lead you to believe. 

“Instead of rising steadily, atmospheric oxygen levels stabilized at 2% by volume for about two billion years before increasing to today's level of 21%,” explains Professor John Allen of <a href="https://www.ucl.ac.uk/">University College London</a>’s Genetics, Evolution &amp; Environment department. “The reasons for this have been long debated by scientists and we think we’ve finally found a simple yet robust answer.”

Allen and researchers from UCL, <a href="https://www.qmul.ac.uk/">Queen Mary University of London</a> and <a href="https://www.uni-duesseldorf.de/home/startseite.html">Heinrich-Heine-Universität Düsseldorf</a> have published a study in <a href="https://www.cell.com/trends/plant-science/home">Trends in Plant Sciences</a> proposing for the first time that atmospheric oxygen produced using the enzyme nitrogenase actually prevented the enzyme from working. The researchers posit that a negative feedback loop halted further oxygen from being produced, and began an exceedingly long period of stagnation in the Earth’s history – like two billion years long.

About 2.4 billion years ago, the Proterozoic Eon experienced very little change in the evolution of life, ocean, atmosphere composition, and climate, which is why some refer to it as the “boring billion.”

“There are many ideas about why atmospheric oxygen levels stabilized at 2% for such an incredibly long period of time, including oxygen reacting with metal ions, but remarkably, the key role of nitrogenase has been completely overlooked,” says study co-author Professor William Martin of Heinrich-Heine-Universität Düsseldorf. “Our theory is the only one that accounts for the global impact on the production of oxygen over such a sustained period of time and explains why it was able to rise to the levels we see today, fueling the evolution of life on Earth.”How did Earth finally produced enough oxygen to escape the ‘boring billion’?

The researchers suggest that this negative feedback loop was only broken when plants finally moved onto land roughly 600 million years ago. With the emergence of plants onto land, oxygen producing cells in leaves were physically separated from nitrogenase containing cells in soil, allowing for oxygen to accumulate without inhibiting nitrogenase. 

Their theory is bolstered by evidence within the fossil record showing cyanobacteria began to protect nitrogenase in dedicated cells called heterocysts a little over 400 million years ago – at the time when oxygen levels were already increasing from photosynthesis in land plants.

“Nitrogenase is essential for life and the process of photosynthesis as it fixes nitrogen in the air into ammonia, which is used to make proteins and nucleic acids,” explains co-author Mrs Brenda Thake of Queen Mary University of London. “We know from studying cyanobacteria in laboratory conditions that nitrogenase ceases to work at higher than 10% current atmospheric levels, which is 2% by volume, as the enzyme is rapidly destroyed by oxygen. Despite this being known by biologists, it hasn’t been suggested as a driver behind one of Earth's great mysteries, until now.”

--

By <a href="mailto:certz@earth.com">Connor Ertz</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: Shutterstock/Digital Images Studio

How did Earth finally produced enough oxygen to escape the ‘boring billion’?

How did Earth finally produced enough oxygen to escape the...

Inventory of plant defense tools is a major step toward disease-resistant crops. An international team of researchers has taken an inventory of the monitoring tools that are used by plants to detect harmful microbes. This catalog represents a major step forward in understanding plant biology and has important implications for the improved management of dangerous <a href="http://www.earth.com/news/global-surveillance-system-crop-diseases/">crop diseases</a>. 

Just like animals, plants depend on their immune systems for protection against pathogenic microbes such as bacteria and fungi. Proteins called Nucleotide-binding Leucine-rich Repeat receptors (NLRs) coordinate efforts to detect the ever-changing variety of microbes present in the plant's environment.

The team set out to identify the full spectrum of NLRs produced by plants and to investigate how much these receptors vary within a typical plant species. The study was focused on Arabidopsis plants, which come under attack by pathogenic organisms of all types.

In the lab of Detlef Weigel at the Max Planck Institute for Developmental Biology, the experts used advanced sequencing technologies to analyze the genetic diversity of NLRs in plants sampled from Europe, North America, and Asia. 

As expected, the collections of these receptors varied among geographic regions, likely due to their evolutionary response to local pathogens. The team was surprised to find that there is an upper limit on NLR gene numbers across the species.

"While the diversity is perhaps more limited than anticipated, it is the mixing of genes that makes each individual uniquely resistant to a different spectrum of pathogens," explained Weigel.

According to Jonathan Jones at <a href="http://www.tsl.ac.uk/">The Sainsbury Laboratory</a>, the study will change the way researchers approach the subject in future.

"One of the remarkable conclusions that emerge from this study is that so many populations need to be sequenced to define the full immune system repertoire of any plant," said Jones. "Gone are the days when a single reference sequence is sufficient to reveal the secrets of a species; it is now clear that we need to understand the genetic diversity of a species in order to understand its immune system."

The research has the potential to transform our understanding of agriculture and plant evolution. 

"This work will help drive new NLR receptor function discovery for developing disease-resistant crops and also guide the analysis of their evolution across the plant kingdom," said Jeffery Dangl of the Howard Hughes Medical Institute.

Coordination and support for the study was provided by the 2Blades Foundation, an international organization dedicated to understanding plant disease and advancing crop disease resistance. The research was funded in part by the Gordon and Betty Moore Foundation.

The study is published in the journal <a href="https://www.cell.com/">Cell</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Inventory of plant defense tools is a major step toward disease-resistant crops

Inventory of plant defense tools is a major step toward...

A new study from the <a href="https://en.natmus.dk/">National Museum of Denmark</a> shows that migration patterns shifted during the southern Scandinavian <a href="http://www.earth.com/news/foxes-domesticated-bronze-age/">Bronze Age</a>, which took place in modern-day Denmark during the 2nd millennium B.C. Evidence shows that migrants of varied backgrounds traveled from distant lands to take part in the economic growth happening in the Nordic region.

During the 2nd and 3rd millennia B.C., many significant migrations to western Europe took place, and only increased after southern Scandinavia became the hub for long-distance metal trade throughout Europe, which started at around 1600 B.C. By the later millennia, the Nordic Bronze Age peaked and wealth and migrants flooded into the area.

"Around 1600 BC, the amount of metal coming into southern Scandinavia increased dramatically, arriving mostly from the Italian Alps, whereas tin came from Cornwall in south England,” said co-author Kristian Kristiansen. “Our results support the development of highly international trade, a forerunner for the Viking Age period."

The Museum’s Karin Frei, Kristiansen, and colleagues examined ancient skeletal remains of 88 people from 37 localities across modern Denmark to investigate the migratory pattern shifts during the Bronze Age. Using strontium isotopes found in tooth enamel, which record geographic signatures, Frei and the team were able to identify where individuals originally hailed from.

[caption id="attachment_1876819" align="aligncenter" width="626"]<a href="https://www.earth.com/wp-content/uploads/2019/08/fossils.jpg"><img class="wp-image-1876819 size-full" src="https://www.earth.com/wp-content/uploads/2019/08/fossils.jpg" alt="" width="626" height="469" /></a> Image Credit: Cristina Jensen[/caption]

Beginning at around 1600 B.C., and spanning into the Nordic Bronze Age, the geographic signal of migrants became more diverse. The authors suggest, via their study published in <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0219850">PLOS ONE</a>, that this migratory shift could have established new cultural alliances within southern Scandinavia, however, more research into ancient DNA could provide insight into this theory.

"Our data indicates a clear shift in human mobility at the breakthrough point of the Nordic Bronze Age, when an unprecedented rich period in southern Scandinavia emerged,” Frei said. “This suggests to us that these aspects might have been closely related."

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Main Image Credit: Marie Louise Jørkov

Wide variety of migrants traveled to Denmark during the Nordic Bronze Age

A new study from the National Museum of Denmark shows...

Cranial modification may have been used as a way to show cultural affiliation during the 5th and 6th centuries in Croatia, a time when humans were moving across Europe in the Great Migration Period.

Artificial Cranial Deformation (ACD) has been practiced across multiple cultures and countries through the ages. 

Archaeologists have uncovered modified skulls in <a href="https://www.earth.com/news/ancient-people-elongated-skulls/">China</a> dating back 5,000 to 12,000 years, and an ancient burial site in Mexico containing bones that dated to 945 A.D. to 1308 A.D. made headlines with the <a href="https://abcnews.go.com/blogs/headlines/2012/12/alien-looking-human-skulls-found-in-mexico/">“alien-like” skulls discovered there</a>. 

In a new study, researchers from the <a href="https://www.univie.ac.at/en/">University of Vienna</a> and the <a href="https://inantro.hr/en/homepage-eng/">Institute for Anthropological Research in Croatia</a> examined skeletons that were excavated from the Hermanov vinograd archaeological site in Osijek, Croatia in 2013. 

Three human skeletons were discovered in a pit dating to 415 to 560 CE, and two of the skeletons had modified skulls. One of the skulls had been elongated, and another had been compressed and heightened. 

[caption id="attachment_1876814" align="aligncenter" width="648"]<a href="https://www.earth.com/wp-content/uploads/2019/08/cranial.jpg"><img class="size-full wp-image-1876814" src="https://www.earth.com/wp-content/uploads/2019/08/cranial.jpg" alt="" width="648" height="638" /></a> CT scans of the cranial deformation. Image Credit: M Kavka[/caption]

The researchers used genetic, isotopic, and skeletal analysis to study the bones. All three skeletons were male, aged between 12 and 16 years old. The two with cranial modifications has very different genetic lineages. 

One of the skeletons discovered is the first person with mostly East Asian ancestry to be identified in Europe during the Great Migration Period. 

The find marks the oldest known evidence of ACD discovered in Croatia, and the researchers hypothesize that the practice may have been used as a way to distinguish different cultural groups.  

It is unclear if ACD was a common practice or unique to the individuals discovered. 

“The most striking observation, based on nuclear ancient DNA, is that these individuals vary greatly in their genetic ancestries,” said Dr. Mario Novak, an author of the study which was published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0216366">PLOS ONE. </a>

--

By<a href="mailto:kayvandette@gmail.com"> Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer 

Image Credit: Shutterstock/ Derek R. Audette

Evidence of early cranial modification found in Croatia

Cranial modification may have been used as a way to...

Experts may have just pinpointed how sea-surface temperature patterns influence the number, strength, and distribution of April tornadoes across the south-central region of the United States.

Published by the <a href="https://www.aaas.org/">American Association for the Advancement of Science</a>, the study highlights the fact that changing climate patterns such as warming trends have the potential to affect tornado formation within seasons.

The research may ultimately lead to the development of improved methods for predicting <a href="http://www.earth.com/news/tornado-activity-shifting-eastward/">tornadoes</a>, which would help reduce fatalities and widespread property loss during peak tornado months. 

In 2011, nearly 1,700 tornadoes claimed over 500 lives and caused $10 billion in property and crop damage across North America. The next tornado season in 2012 produced 900 tornadoes and resulted in 70 deaths.

In an effort to better understand the potential causes underlying such fluctuations from year to year, the research team conducted a month-by-month analysis of tornado counts across North America from 1954 to 2016. In particular, the investigation was focused on springtime events across Tornado Alley. 

When comparing the number of tornadoes in May to corresponding sea surface temperature patterns, the researchers found no significant connection. This finding indicates that tornadoes occurring in May are more strongly influenced by internal atmospheric processes. 

On the other hand, the team discovered that April tornado activity is strongly influenced by large-scale climate patterns. For example, the April tornadoes were found to be more frequent when equatorial Pacific and eastern North Pacific waters were cooler and subtropical Pacific and western Atlantic waters were warmer. 

Based on these results, the study authors propose that shifting weather patterns within seasons are important factors to consider when measuring the impact of climate change on tornado frequencies.

The study is published in the journal <a href="https://www.bmj.com/">The BMJ</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Paid for by <a href="http://earth.com">Earth.com</a>

Image Credit: Shutterstock/Minerva Studio

April tornadoes are strongly influenced by changing climate patterns

Experts may have just pinpointed how sea-surface temperature patterns influence...

Just a few years ago, there was a significant decline in the <a href="http://www.earth.com/news/drinking-stations-koala-bears-hydrated/">koala</a> population of Cape Otway in Victoria, Australia. 

“In 2013 the koala population reached very high densities, leading them to defoliate their preferred food tree species, manna gum,” explains Dr. Michaela Blyton of the <a href="https://www.uq.edu.au/">University of Queensland</a>, an author on a new study published in <a href="https://animalmicrobiome.biomedcentral.com/">Animal Microbiome</a>. “This led to 70 per cent mortality due to starvation, which was very distressing.”

Blyton noticed that even though the koalas were dying of starvation, many of them refused to start eating their less-preferred tree species, known as messmate. This was made stranger by the fact that some koalas feed only on messmate.

“This led me and colleague Dr. Ben Moore at Western Sydney University to wonder if the microbes present in koalas’ guts - their microbiomes - were limiting which species they could eat, and if we could allow them to expand their diet with fecal inoculations,” says Blyton. 

Thus began Blyton’s messy experiment of catching wild koalas and keeping them in temporary captivity in order to collect the end stage product of their messmate diets – less formally known as “poo.”

“We collected poo from radio-collared wild koalas that ate messmate, concentrated the microorganisms in the poo, packaged it into acid-resistant capsules and gave them to the captive koalas,” explains Dr. Blyton. “We then monitored how much messmate the koalas were willing to eat over an 18-day period and assessed how the microbiomes changed after the inoculations, comparing their diets to those of control koalas that received manna gum microbes.”

The results at the end of this period showed that the fecal inoculations actually changed the koalas’ microbiomes and allowed them to eat messmate. 

“This could affect all aspects of their ecology including nutrition, habitat selection and resource use,” says Blyton. “Koalas may naturally have trouble adapting to new diets when their usual food trees become over browsed or after being moved to a new location. This study provides a proof of concept for the use of encapsulated fecal material to successfully introduce and establish new microbes in koalas’ guts.”

Blyton believes that this procedure could be used to help adjust koalas’ microbiomes before they are moved to environments where they have the habitat and food source to survive. The inoculation may also serve as a source of probiotics during and after antibiotic treatment. So next time you complain about needing to swallow a pill, just be thankful that its contents are bound to be more appetizing than a koala’s fecal inoculation. 

--

By <a href="mailto:certz@earth.com">Connor Ertz</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: The University of Queensland

How fecal inoculations could help save koalas

Just a few years ago, there was a significant decline...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Nushagak Bay in southwest Alaska

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Lake Trasimeno in Central Italy

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



In 1968, Kainji Lake was created by the construction of the Kainji Dam. The Niger River, the third longest in Africa, enters the lake in the north.&nbsp;



According to <a href="https://www.earth.com/news/rivers-in-the-american-west-are-a-lifesaving-resource-for-birds/">ESA</a>, the creation of the lake submerged Foge Island and the town of Bussa and permanently flooded other riverine settlements, leaving around 50,000 people displaced.&nbsp;



Large parts of Foge Island are temporarily exposed during low water tides, and the land is often used by migrating fishermen. Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. 



Wild mammals occur at relatively low densities due to illegal hunting. Lake Kainji has suffered a dramatic decline as a fishery due to the high numbers of artisanal and subsistence fisherfolk using the lake. It has been suggested that a period of closure, together with controlled fishing rights may help improve fish stocks.



Kainji Lake National Park is the oldest of its kind in Nigeria. The park contains three distinct areas: a part of the Kainji Lake, the Borgu Game Reserve to the west of the lake, and the Zugurma Game Reserve to the southeast. The park is home to around 65 mammal species, 350 bird species, and 30 species of reptiles and amphibians. 



Video/ Image Credit: European Space Agency&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Kainji Lake in north central Nigeria

[sendtonews key="iuA5mpp3jv-1641775-12187" type="single"] Today’s Video of the Day from the...

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Today’s Video of the Day from <a href="https://www.igb.illinois.edu/">Carl R. Woese Institute for Genomic Biology</a> reveals how scientists can modify common crops like soybean, rice, and wheat to protect them from heat stress.



“We need to double crop production by 2050 to feed a growing global population, and not only are we not on track to do that, but climate change is further complicating things,” said Amanda Cavanagh, a lecturer at the University of Essex. 



The study is part of Realizing Increased Photosynthetic Efficiency (RIPE), an international research project that aims to develop food crops that turn the sun’s energy into food more efficiently.



“Using an engineering approach we designed multiple alternative metabolic pathways to photorespiration. Testing them in the field showed increases in productivity which led Amanda to significantly move the project forward by showing our engineered plants can withstand pretty extreme temperature stress,” said study co-author and RIPE researcher Paul South.&nbsp;



“As the climate changes and temperature stresses increase the pressure on our global food supply, farmers will need every tool available including engineering approaches like the synthetic biology used here to maintain safe and productive harvests.”



The experts tested plants modified to have more efficient photorespiration to see if they were better adapted to warmer temperatures.&nbsp;



The team found that the engineered plants produced 26 percent more biomass than the wild-type plants exposed to the same temperatures, and had 15 percent less yield loss under the higher temperatures.



Video Credit: Amanda Nguyen/University of Illinois



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Designing crops that can beat the heat

[sendtonews key="QGPzYnXEtN-1712599-12187" type="single"] Today’s Video of the Day from Carl...

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Today’s Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> explores the ability of salt to transform the way that foods and beverages taste. Salt is known to cover up undesirable flavors, such as bitterness in coffee or beer, but how exactly does sodium chloride change the taste of other compounds?



One previous study showed that, not only does salt suppress bitterness, but also enhances sweetness and sourness. Another study revealed that bitterness reduction by salt seems to be happening at the tongue receptor level as well as in the brain.&nbsp;



While it is known that salt taste is mediated by the presence of sodium channels in the form of taste buds, experts believe that there is also an unknown receptor responsible for how we taste salt that has not yet been identified.&nbsp;



Video Credit: ACS Reactions



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

How does salt makes things taste better?

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Santiago, the capital city of Chile. The city is located in the center of the Santiago Metropolitan Region, which has a population of about eight million people.&nbsp;



'The weather of Santiago resembles the Mediterranean climate with dry and warm summers with temperatures reaching up to 35°C (from October to March) and cool and humid winters that can drop to 0°C (from April to September)."



"The city lies in the centre of the country’s central valley around 80 km from the Pacific Ocean to the west and borders Argentina to the east. A tiny part of Argentina is visible in the top-right corner of the image where the mountain crest of the Andes Mountains acts as a divider between the two countries," says ESA.



Video/ Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Santiago, Chile in South America

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Spiral,Galaxy,,Illustration,Of,Milky,Way

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Astronomers at <a href="https://www.jhu.edu/">Johns Hopkins University</a> have created an interactive map of the universe, including the actual position and real colors of 200,000 galaxies. The map allows the public to access data that was previously only available to scientists.



The map was developed using data collected by the Sloan Digital Sky Survey. For over two decades, a telescope in New Mexico was aimed at slightly different locations to capture the night sky.&nbsp;



"Growing up I was very inspired by astronomy pictures, stars, nebulae and galaxies, and now it's our time to create a new type of picture to inspire people," said map creator Brice Ménard, a professor at Johns Hopkins. "Astrophysicists around the world have been analyzing this data for years, leading to thousands of scientific papers and discoveries. But nobody took the time to create a map that is beautiful, scientifically accurate, and accessible to people who are not scientists. Our goal here is to show everybody what the universe really looks like."



"In this map, we are just a speck at the very bottom, just one pixel. And when I say we, I mean our galaxy, the Milky Way which has billions of stars and planets. We are used to seeing astronomical pictures showing one galaxy here, one galaxy there or perhaps a group of galaxies. But what this map shows is a very, very different scale."



"From this speck at the bottom, we are able to map out galaxies across the entire universe, and that says something about the power of science."



The <a href="https://mapoftheuniverse.net/">interactive map</a> is available online, where it can be downloaded for free.



Video Credit: Johns Hopkins&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Interactive map of the universe includes 200,000 galaxies

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes the first comprehensive estimate of carbon density in the Saharan, Sahel, and Sudanian zones of Africa. In an effort to measure the amount of carbon stored across these drylands, a team of scientists used high-resolution satellite images and artificial intelligence to map nearly 10 billion individual trees. 



"The high spatial resolution (50 cm) combined with AI and field measurements used in this study is key to improving tree inventories in drylands," said Pierre Hiernaux, a French researcher working for NASA. "The ever-increasing availability of very high-resolution satellite imagery will make it possible to assess carbon pools and their dynamics at the individual tree level on a global scale."



"This study is exceptional because it is pioneering a type of approach that will revolutionize the monitoring of trees and forests on a global scale: in the short term, it will be possible to map the world's trees from the centre of the Amazon to our schoolyards," said <a href="https://www.inrae.fr/en">INRAE</a> researcher Jean-Pierre Wigneron.



"Many fields of application will become much more efficient and accurate, such as tracking carbon stocks, biodiversity, monitoring logging and protection against illegal forest degradation, in near real time.”



Video Credit: NASA Goddard&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Remote sensing will revolutionize the way we monitor trees

[sendtonews key="EjmSP20gQK-2593093-12187" type="single"] Today's Video of the Day from NASA...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Dublin, the capital and largest city of Ireland. Beyond its pub culture, Dublin is known as a modern culinary destination and a UNESCO City of Literature.



"Dublin is located near the midpoint of Ireland’s east coast in the province of Leinster. The city, which covers an area of around 115 square kilometers, is bordered by the Dublin Mountains, a low mountain range to the south, and is surrounded by flat farmland to the north and west," says ESA.



"The city straddles the River Liffey, which rises in the Wicklow Mountains and flows around 80 kilometers eastwards through the city of Dublin, in which it is canalised and bordered with quays. It then empties into Dublin Bay, an arm of the Irish Sea."



Dublin has an abundance of green spaces, including one of the largest enclosed public parks in any European capital city. Phoenix Park, which was originally formed as a royal hunting park in the 1660s, includes 707 hectares of green space.



Video Credit: ESA&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The city of Dublin on Ireland's east coast

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the province of Zaragoza in northeast Spain. The image was captured by the Copernicus Sentinel-2 mission.



"Together with the provinces of Huesca and Teruel, Zaragoza formed the old kingdom of Aragon. Its capital, also called Zaragoza (not visible in this image) is home to around half of Aragon’s population," says ESA.



"The Ebro River can be seen winding its way through the province from west to east in this image. Between its source in the Cantabrian Mountains in the northwest and its delta on the Mediterranean coast, the Ebro River is fed by more than 200 tributaries as it flows 910 km across much of northern Spain."



Since rainfall is very scarce in this region, irrigation in the Ebro basin is critically important. In the valleys surrounding the Ebro River, many fields are used for growing crops such as corn, wheat, and barley.



Video/ Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The province of Zaragoza in northeast Spain

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> features a visual dataset of.methane emissions from wetlands across the globe. Atmospheric methane levels have reached record highs in recent years, and wetlands are a major source of these emissions.&nbsp;



"Methane is an important greenhouse gas that contributes substantially to global warming. On a molecule by molecule basis, methane is much more efficient at trapping heat than carbon dioxide, the main driver of warming," says NASA.



"Though human activities, including agriculture, oil and natural gas production and use, and waste disposal, collectively contribute the majority of methane to the atmosphere, about a third of total methane emissions comes from wetlands."&nbsp;



According to NASA, understanding methane emissions from wetlands and other natural sources is critically important for scientists and policymakers who are working to combat climate change by reducing emissions from human activities.



Video Credit: NASA Goddard



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Wetlands are a major source of methane emissions

[sendtonews key="f8fukm28Vz-2491833-12187" type="single"] Today's Video of the Day from NASA...

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> reveals the evolution of the Columbia Glacier in southeastern Alaska. Columbia is among the fastest shrinking glaciers in the world, and the video documents its rapid retreat over the years.&nbsp;



Columbia Glacier is a large, multi-branched calving glacier that flows out of the Chugach Mountains to the Prince William Sound.&nbsp;



According to USGS, Columbia had a long history of stability prior to 1980, with a length 41 miles, and small, short-lived advances or retreats.



In the years since 1980, however, satellite images have captured Columbia’s alarming retreat. By using false-color images, scientists can distinguish between snow and ice, open water, vegetation, and rocky debris on the glacier’s surface.



The series of false-color images featured in today's video were acquired over the span of 35 years. You can see that by 2021, the glacier’s main branch had retreated about 15 miles from its initial position.



The Columbia Glacier has also lost more than 50 percent of its volume, mostly due to calving. <a href="https://www.earth.com/video/nasa-reveals-3d-visual-of-an-atmospheric-river/">NASA</a> reports that while climate change likely started the retreat, mechanical processes kept the disintegration going.



The NASA images are provided by Jesse Allen, Robert Simmon, Joshua Stevens, and Lauren Dauphin using data from Landsat satellites, from the U.S. Geological Survey, and data from MODIS on NASA’s Terra satellite. The structure of Columbia’s moraine played a large role in the stability of the glacier before 1980. 



Like other tidewater glaciers, the Columbia built up a moraine over time, and the mixture of ice and rock functioned like a dam keeping out the sea. It was supported on one end by the shoreline and by the underwater terminal moraine at the other.



Video Credit: NASA Earth Observatory/&nbsp; NASA’s Scientific Visualization Studio



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The rapid retreat of the Columbia Glacier

[sendtonews key="0879czfG3k-1785905-12187" type="single"] Today’s Video of the Day from NASA...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Pyrenees Mountains, which form a natural boundary between France and Spain in southwest Europe.



The mountain range is 430 kilometers in length. It stretches from the Mediterranean Sea on the east to the Atlantic Ocean on the west.



At an elevation of 3404 meters, Pico de Aneto is the highest mountain peak in the Pyrenees, and the third-highest peak in Spain. Pico de Aneto is located in the Posets-Maladeta Natural Park, which spans more than 82,000 acres.&nbsp;



"Geological studies have revealed that the Pyrenees Mountains have been around for longer than the Alps, with their sediments first deposited in coastal basins during the Paleozoic and Mesozoic eras," reports ESA.



"The entire mountain range formed due to the upwelling of large sedimentary rocks by the collision of the Iberian and the Eurasian plate around 100 to 150 million years ago, followed by intense erosion from ice and water."



The western Pyrenees receive more precipitation due to moisture blowing in from the Atlantic Ocean. The mountain range contains many lakes, several small glaciers, and some of the highest waterfalls in Europe.



Video &amp; Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The Pyrenees Mountains in southwest Europe

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Today’s Video of the Day from <a href="https://www.stowers.org/">Stowers Institute for Medical Research</a> describes why experts are studying zebrafish to gain a better understanding of how the immune system responds to injury. Zebrafish have the ability to repair and regenerate organs.



“Organ regeneration offers an exciting opportunity for studying the immune system and to inquire why some species can regenerate organs like the heart or missing limbs while others like humans cannot,” explained Dr. Tatjana Piotrowski.



Zebrafish sensory organ hair cells are an ideal system to investigate the pathways and cell types involved in regeneration since they are easily destroyed with antibiotics and begin regenerating within five hours. This enabled the researchers to identify the exact timing and genetic programs for each anti-inflammatory macrophage activation state.&nbsp;



“Our hypothesis is that human macrophages do not receive the proper chemical activation 'cocktail' to instruct pro-regenerative processes,” said Dr. Nicolas Denans. “Identifying the molecular recipe of macrophage activation in zebrafish may one day enable us to design regenerative immunotherapies in humans.”&nbsp;&nbsp;&nbsp;



“The new evidence is a valuable resource for comparative studies on the genetic programs involved in macrophage-mediated repair and regeneration. In other words, different types of injuries may induce different kinds of inflammatory responses. We want to decipher whether this 'language' is universal or if there are a variety of dialects."



Video Credit: Stowers Institute for Medical Research&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

How the immune system responds to injury

[sendtonews key="0dEcERCq61-2283382-12187" type="single"] Today’s Video of the Day from Stowers...

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes how record-breaking heat expressed itself around the world in 2022.



Scientists have determined that 2022 was the 5th warmest year since 1880. Furthermore, the last nine consecutive years have been the warmest on record.



From devastating floods and wildfires to natural disasters like Hurricane Ian, 2022 showed us yet again how a warming climate affects people across the globe.&nbsp;



"As we look back at 20:22 and years past, we see that each year we better understand the challenges we face and how important it is to meet them," says NASA.



Video/ Image Credit: NASA Goddard



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

2022 illustrated the consequences of a warming climate

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes two exoplanets that are orbiting a star 218 light-years away. A team of researchers led by the University of Montreal has found evidence that these planets are "water worlds."



The experts used data from NASA’s Hubble and Spitzer Space Telescopes. They discovered that exoplanets Kepler-138 c and Kepler-138 could be composed largely of water.



"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," explained study co-author Björn Benneke.&nbsp;



"However, we have now shown that these two planets, Kepler-138 c and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water. It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time."



Video Credit: NASA Goddard



Image Credit: NASA, ESA, and Leah Hustak (STScI)



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Two distant planets may be "water worlds"

[sendtonews key="QIoVYJqRBi-2434608-12187" type="single"] Today's Video of the Day from NASA...

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Satellites reveal how Earth's systems are interconnected Today’s Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes Earth’s interconnected systems, and how this network is affected by rising temperatures.&nbsp;



During 2020, average global temperatures matched the hottest year on record. The hurricane season was also record-breaking, with many of the storms intensifying at extraordinary speeds. Hot water in the ocean is fuel for hurricanes. The satellite data shows that it's all one interconnected system showing how Satellites reveal how Earth's systems are interconnected.



According to NASA, dust swept up from Northern Africa plays a major role in the formation of hurricanes, and is also a key source of fertilization in the Amazon rainforest. As a result of<a href="https://www.earth.com/news/seagrass-wasting-disease-is-fueled-by-climate-change/"> climate</a> change, dust plumes are expected to decline, which will have an effect on vegetation far away.&nbsp;



Images from Earth-observing satellites show how the world’s plant life is affected by natural disasters, fires, and deforestation. Satellites also reveal how widespread changes in vegetation impact waterways,&nbsp; the climate, air quality. Satellites communicate by using radio waves to send signals to the antennas on the Earth. "Earth From Space" is a groundbreaking two-hour special that reveals a spectacular new space-based vision of our planet. 



Video Credit: NASA Goddard&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Satellites reveal how Earth's systems are interconnected

[sendtonews key="JbW4VsY53O-1632195-12187" type="single"] Satellites reveal how Earth's systems are interconnected...

Today’s Video of the Day from the <a href="https://welcome.miami.edu/">University of Miami</a> Rosenstiel School of Marine and Atmospheric Science explores how changes in water temperatures have affected tiger shark habitats and movements in the North Atlantic Ocean. The study reveals that rising temperatures have caused the sharks to shift toward the poles over the past 40 years.



“Tiger shark annual migrations have expanded poleward, paralleling rising water temperatures,” explained study lead author Neil Hammerschlag. “These results have consequences for tiger shark conservation, since shifts in their movements outside of marine protected areas may leave them more vulnerable to commercial fishing.”



The researchers analyzed nine years of tracking data from satellite-tagged tiger sharks, combined with four decades of conventional tag and recapture data provided by National Oceanic and Atmospheric Administration (NOAA) Cooperative Shark Tagging Program.



The experts found that during the last decade of record heat, for every one-degree Celsius increase in water temperatures, tiger sharks migrated further poleward by over 400 kilometers. They also migrated two weeks earlier than usual to waters off the northeastern coast of the United States.



“Given their role as apex predators, these changes to tiger shark movements may alter predator-prey interactions, leading to ecological imbalances, and more frequent encounters with humans,” concluded Professor Hammerschlag.



Video Credit: University of Miami Rosenstiel School of Marine and Atmospheric Science



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Tiger sharks are shifting poleward as temperatures rise

Today’s Video of the Day from the University of Miami...