Scientists just broke the record for the coldest temperature ever measured in a lab: They achieved the bone-chilling temperature of 38 trillionths of a degree above -273.15 Celsius by dropping magnetized gas 393 feet (120 meters) down a tower.
The team of German researchers was investigating the quantum properties of a so-called fifth state of matter: Bose-Einstein condensate (BEC), a derivative of gas that exists only under ultra-cold conditions.
While in the BEC phase, matter itself begins to behave like one large atom, making it an especially appealing subject for quantum physicists who are interested in the mechanics of subatomic particles.
Temperature is a measure of molecular vibration – the more a collection of molecules moves, the higher the collective temperature.
Absolute zero, then, is the point at which all molecular motion stops – minus 459.67 degrees Fahrenheit, or minus 273.15 degrees C. Scientists have even developed a special scale for extremely cold temperatures, called the Kelvin scale, where zero Kelvin corresponds to absolute zero.
Near absolute zero, some weird things start to happen. For example, light becomes a liquid that can literally be poured into a container, according to research published in 2017 in the journal Nature Physics. Supercooled helium stops experiencing friction at very low temperatures, according to a study published in 2017 in the journal Nature Communications. And in NASA’s Cold Atom Lab, researchers have even witnessed atoms existing in two places at once.
In this record-breaking experiment, scientists trapped a cloud of around 100,000 gaseous rubidium atoms in a magnetic field inside a vacuum chamber. Then, they cooled the chamber way down, to around 2 billionths of a degree Celsius above absolute zero, which would have been a world record in itself, according to NewAtlas.
But this wasn’t quite frigid enough for the researchers, who wanted to push the limits of physics; to get even colder, they needed to mimic deep-space conditions. So the team took their setup to the European Space Agency’s Bremen drop tower, a microgravity research center at the University of Bremen in Germany.
By dropping the vacuum chamber into a free fall while switching the magnetic field on and off rapidly, allowing the BEC to float uninhibited by gravity, they slowed the rubidium atoms’ molecular motion to almost nothing.
The resulting BEC stayed at 38 picokelvins – 38 trillionths of a Kelvin – for about 2 seconds, setting “an absolute minus record”, the team reported Aug. 30 in the journal Physical Review Letters.
The previous record of 36 millionths of a Kelvin, was achieved by scientists at the National Institute of Standards and Technology (NIST) in Boulder, Colorado with specialized lasers.
The coldest known natural place in the universe is the Boomerang Nebula, which lies in the Centaurus constellation, about 5,000 light years from Earth. Its average temperature is -272 C (about 1 Kelvin) according to the European Space Agency.
The researchers of the new study said in a statement that, theoretically, they could sustain this temperature for as long as 17 seconds under truly weightless conditions, like in space. Ultra cold temperatures may one day help scientists build better quantum computers, according to researchers at MIT.
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This article was originally published by Live Science. Read the original article here.
Scientists just broke the record for the coldest temperature ever measured in a lab: They achieved the bone-chilling temperature of 38 trillionths of a degree above -273.15 Celsius by dropping magnetized gas 393 feet (120 meters) down a tower.
The team of German researchers was investigating the quantum properties of a so-called fifth state of matter: Bose-Einstein condensate (BEC), a derivative of gas that exists only under ultra-cold conditions. While in the BEC phase, matter itself begins to behave like one large atom, making it an especially appealing subject for quantum physicists who are interested in the mechanics of subatomic particles.
Related: 10 science records broken in 2020
Temperature is a measure of molecular vibration — the more a collection of molecules moves, the higher the collective temperature. Absolute zero, then, is the point at which all molecular motion stops — minus 459.67 degrees Fahrenheit, or minus 273.15 degrees C. Scientists have even developed a special scale for extremely cold temperatures, called the Kelvin scale, where zero Kelvin corresponds to absolute zero.
Near absolute zero, some weird things start to happen. For example, light becomes a liquid that can literally be poured into a container, according to research published in 2017 in the journal Nature Physics. Supercooled helium stops experiencing friction at very low temperatures, according to a study published in 2017 in the journal Nature Communications. And in NASA’s Cold Atom Lab, researchers have even witnessed atoms existing in two places at once.
In this record-breaking experiment, scientists trapped a cloud of around 100,000 gaseous rubidium atoms in a magnetic field inside a vacuum chamber. Then, they cooled the chamber way down, to around 2 billionths of a degree Celsius above absolute zero, which would have been a world record in itself, according to NewAtlas.
But this wasn’t quite frigid enough for the researchers, who wanted to push the limits of physics; to get even colder, they needed to mimic deep-space conditions. So the team took their setup to the European Space Agency’s Bremen drop tower, a microgravity research center at the University of Bremen in Germany. By dropping the vacuum chamber into a free fall while switching the magnetic field on and off rapidly, allowing the BEC to float uninhibited by gravity, they slowed the rubidium atoms’ molecular motion to almost nothing. The resulting BEC stayed at 38 picokelvins – 38 trillionths of a Kelvin – for about 2 seconds, setting “an absolute minus record”, the team reported Aug. 30 in the journal Physical Review Letters. The previous record of 36 millionths of a Kelvin, was achieved by scientists at the National Institute of Standards and Technology (NIST) in Boulder, Colorado with specialized lasers.
The coldest known natural place in the universe is the Boomerang Nebula, which lies in the Centaurus constellation, about 5,000 light years from Earth. Its average temperature is -272 C (about 1 Kelvin) according to the European Space Agency. ]
The researchers of the new study said in a statement that, theoretically, they could sustain this temperature for as long as 17 seconds under truly weightless conditions, like in space. Ultra cold temperatures may one day help scientists build better quantum computers, according to researchers at MIT.
Exoplanets – planets outside our Solar System – continue to provide astronomers with fascinating glimpses of other worlds, including the one designated WASP-76b. On this inferno-like planet, almost the size of Jupiter, the daytime surface temperatures are hot enough to vaporize iron, which could fall as rain on the slightly cooler night side.
Now researchers have given WASP-76b another look and concluded that it might actually be hotter than previously thought. Key to that conclusion is the discovery of ionized calcium, which would need “significantly hotter” conditions to form than have previously been outlined in studies.
As we know from previous research, temperatures on the surface of WASP-76b are thought to climb to around 4,400 degrees Fahrenheit (2,246 Celsius) on the daytime side – but that might be something of an underestimation if the new and updated temperature profile turns out to be more accurate.
“We’re seeing so much calcium; it’s a really strong feature,” says astrophysicist Emily Deibert from the University of Toronto in Canada. “This spectral signature of ionized calcium could indicate that the exoplanet has very strong upper atmosphere winds, or the atmospheric temperature on the exoplanet is much higher than we thought.”
Discovered in 2016, WASP-76b is known as a ‘hot Jupiter’ exoplanet because it’s so close to its star – an orbit takes just 1.8 Earth days. It’s around 640 light-years away from our position in the Universe. It’s also tidally locked, meaning the same side of the planet always faces its star, itself slightly hotter than our Sun.
Here the researchers used data from the Gemini North Telescope in Hawaii to look at the moderate temperature zone of the planet, the border between day and night. They used a process of transit spectroscopy, where the light of an exoplanet’s star shines through its atmosphere, all the way back to Earth.
The quality and composition of that light enable us to make calculations about the atmosphere at a variety of different depths. In this case, the team was able to identify a rare trio of spectral lines, readings that indicate the presence of ionized calcium.
“It’s remarkable that with today’s telescopes and instruments, we can already learn so much about the atmospheres – their constituents, physical properties, presence of clouds and even large-scale wind patterns – of planets that are orbiting stars hundreds of light-years away,” says astronomer Ray Jayawardhana from Cornell University in New York.
Spectroscopy techniques such as the one used here enable astronomers to discover all kinds of secrets about exoplanets hundreds of light-years (or more) away: everything from the details of the planet’s rotation to the wind patterns on the surface.
That means that as more and more of these exoplanets are discovered and cataloged, researchers can group them for easier reference. Ultimately we end up learning more about our place in the Universe and where we might find other forms of life.
This study is part of a multi-year project looking at a minimum of 30 exoplanets, called Exoplanets with Gemini Spectroscopy (ExoGemS). Once the project is completed, experts should have a much better idea of the diversity of atmospheres that exist on these distant and exotic worlds.
“As we do remote sensing of dozens of exoplanets, spanning a range of masses and temperatures, we will develop a more complete picture of the true diversity of alien worlds – from those hot enough to harbor iron rain to others with more moderate climates, from those heftier than Jupiter to others not much bigger than the Earth,” says Jayawardhana.
The research has been published in the Astrophysical Journal Letters.
We are just days away from the official announcement of the new Apple Watch Series 7, which is expected to have a brand new flat design. Meanwhile, reliable analyst Ming-Chi Kuo today shared some hints about what to expect for Apple Watch Series 8 in 2022 and also for future versions of AirPods.
As Apple has been more focused on working on the new Apple Watch Series 7 design, rumors suggest that this year’s version will not have any major changes when it comes to health sensors. For instance, the company has been testing a blood glucose monitor for Apple Watch, but all evidence points to that feature being delayed.
According to Kuo, the demand for Apple Watch Series 8 may be high next year despite all the design changes coming to this year’s Series 7. That’s because the addition of new health sensors that won’t be included in this year’s Apple Watch should make customers consider the upgrade.
The analyst mentioned in an investor note seen by 9to5Mac that the next-generation Apple Watch will have temperature measurement capabilities, which would let users check their body temperature using just their watch. This is not the first time this feature has been rumored, as Bloomberg’s Mark Gurman said last month that “we may see a body-temperature sensor” in next year’s Apple Watch.
In addition to the Apple Watch, Kuo also made a brief comment about the future of AirPods. The analyst believes that Apple will add health features to its truly wireless earphones in about two years. However, it’s unclear what those features are and which models of AirPods will get them.
Earlier this year, a Bloomberg report revealed that Apple is working on a second-generation AirPods Pro with “new motion sensors to enable onboard fitness tracking.” The report says that the new AirPods Pro will arrive in 2022.
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With climate change causing temperatures to rise across the globe, extreme heat is becoming more and more of a health threat. The human body is resilient, but it can only handle so much. So what is the highest temperature people can endure?
The answer is straightforward: a wet-bulb temperature of 95 degrees Fahrenheit (35 degrees Celsius), according to a 2020 study in the journal Science Advances. Wet-bulb temperature is not the same as the air temperature you might see reported by your local forecaster or favorite weather app. Rather, a wet-bulb temperature is measured by a thermometer covered in a water-soaked cloth, and it takes into account both heat and humidity. The latter is important because with more water in the air, it’s harder for sweat to evaporate off the body and cool a person down.
If the humidity is low but the temperature is high, or vice versa, the wet-bulb temperature probably won’t near the human body’s tipping point, said Colin Raymond, a postdoctoral researcher at NASA’s Jet Propulsion Laboratory who studies extreme heat. But when both the humidity and the temperature are very high, the wet-bulb temperature can creep toward dangerous levels. For example, when the air temperature is 115 F (46.1 C) and the relative humidity is 30%, the wet-bulb temperature is only about 87 F (30.5 C). But when the air temperature is 102 F (38.9 C) and the relative humidity is 77%, the wet-bulb temperature is about 95 F (35 C).
Related: Why is humidity so uncomfortable?
The reason people can’t survive at high heat and humidity is that they can no longer regulate their internal temperature. “If the wet-bulb temperature rises above the human body temperature, you can still sweat, but you’re not going to be able to cool your body to the temperature that it needs to operate at physiologically,” Raymond told Live Science.
At this point, the body becomes hyperthermic — above 104 F (40 C). This can lead to symptoms such as a rapid pulse, a change in mental status, a lack of sweating, faintness and coma, according to the National Institutes of Health.
A wet-bulb temperature of 95 F won’t cause immediate death, however; it probably takes about 3 hours for that heat to be unsurvivable, Raymond said. There’s no way to know for sure the exact amount of time, he said, but studies have tried to estimate it by immersing human participants in hot water tanks and removing them when their body temperatures began to rise uncontrollably. There also isn’t a way to confirm that 95 F is the exact wet-bulb temperature that’s unsurvivable; Raymond estimated that the true number is in the range of 93.2 F to 97.7 F (34 C to 36.5 C).
Although no one can live at a wet-bulb temperature higher than about 95 F, lower temperatures can also be deadly. Exercise and exposure to direct sunlight make it easier to overheat. Older people; people with certain health conditions, such as obesity; and people who take antipsychotics can’t regulate their temperature as well, so it’s easier for heat to kill them. This is why people sometimes die in heat that does not reach a wet-bulb temperature of 95 F.
Luckily, air conditioning can save people from unlivable heat. But, of course, not all people have access to it, and even in places where many people have air conditioning, the electrical grid may be unreliable, Raymond said.
Few locations have hit a wet-bulb temperature of 95 F in recorded history, according to the Science Advances study. Since the late 1980s and 1990s, hotspots have been the Indus River Valley of central and northern Pakistan and the southern shore of the Persian Gulf. “There are places that are already starting to experience these conditions for an hour or two,” Raymond said. “And with global warming, that’s only going to become more frequent.” Locations that are at risk of these temperatures in the next 30 to 50 years include northwest Mexico, northern India, Southeast Asia and West Africa, he added.
“Unfortunately, with the climate change that’s already locked in, we’ll continue to warm up a fair bit, even if we stopped emitting greenhouse gases today,” Raymond said. “I think it’s inevitable that those places I mentioned will be grappling with this issue for the foreseeable future, and I hope more places don’t get added to that list.”
Paul Chu (right) is Founding Director and Chief Scientist at the Texas Center for Superconductivity at the University of Houston (TcSUH). Liangzi Deng (left) is research assistant professor of physics at TcSUH. Credit: University of Houston
In a critical next step toward room-temperature superconductivity at ambient pressure, Paul Chu, Founding Director and Chief Scientist at the Texas Center for Superconductivity at the University of Houston (TcSUH), Liangzi Deng, research assistant professor of physics at TcSUH, and their colleagues at TcSUH conceived and developed a pressure-quench (PQ) technique that retains the pressure-enhanced and/or -induced high transition temperature (Tc) phase even after the removal of the applied pressure that generates this phase.
Pengcheng Dai, professor of physics and astronomy at Rice University and his group, and Yanming Ma, Dean of the College of Physics at Jilin University, and his group contributed toward successfully demonstrating the possibility of the pressure-quench technique in a model high temperature superconductor, iron selenide (FeSe). The results were published in the journal Proceedings of the National Academy of Sciences.
“We derived the pressure-quench method from the formation of the man-made diamond by Francis Bundy from graphite in 1955 and other metastable compounds,” said Chu. “Graphite turns into a diamond when subjected to high pressure at high temperatures. Subsequent rapid pressure quench, or removal of pressure, leaves the diamond phase intact without pressure.”
Chu and his team applied this same concept to a superconducting material with promising results.
“Iron selenide is considered a simple high-temperature superconductor with a transition temperature (Tc) for transitioning to a superconductive state at 9 Kelvin (K) at ambient pressure,” said Chu.
“When we applied pressure, the Tc increased to ~ 40 K, more than quadrupling that at ambient, enabling us to unambiguously distinguish the superconducting PQ phase from the original un-PQ phase. We then tried to retain the high-pressure enhanced superconducting phase after removing pressure using the PQ method, and it turns out we can.”
Dr. Chu and colleagues’ achievement brings scientists a step closer to realizing the dream of room-temperature superconductivity at ambient pressure, recently reported in hydrides only under extremely high pressure.
Superconductivity is a phenomenon discovered in 1911 by Heike Kamerlingh Onnes by cooling mercury below its transition Tc of 4.2 K, attainable with the aid of liquid helium, which is rare and expensive. The phenomenon is profound because of superconductor’s ability to exhibit zero resistance when electricity moves through a superconducting wire and its expulsion of magnetic field generated by a magnet. Subsequently, its vast potential in the energy and transportation sectors was immediately recognized.
To operate a superconducting device, one needs to cool it to below its Tc, which requires energy. The higher the Tc, the less energy needed. Therefore, raising the Tc with the ultimate goal of room temperature of 300 K has been the driving force for scientists in superconductivity research since its discovery.
In defiance of the then-prevailing belief that Tc could not exceed the 30’s K, Paul Chu , and colleagues discovered superconductivity in a new family of compounds at 93 K in 1987, achievable by the mere use of the inexpensive, cost-effective industrial coolant of liquid nitrogen. The Tc has continuously been raised since to 164 K by Chu et al. and other subsequent groups of scientists. Recently a Tc of 287 K was achieved by Dias et al. of Rochester University in carbon-hydrogen-sulfide under 267 gigapascal (GPa).
In short, the advancement of Tc to room temperature is indeed within reach. But for future scientific and technological development of hydrides, characterization of materials and fabrication of devices at ambient pressures is necessary.
“Our method allows us to make the material superconducting with higher Tc without pressure. It even allows us to retain at ambient the non-superconducting phase that exists only in FeSe above 8 GPa. There is no reason that the technique cannot be equally applied to the hydrides that have shown signs of superconductivity with a Tc approaching room temperature.”
The achievement inches the academic community closer toward room-temperature superconductivity (RTS) without pressure, which would mean ubiquitous practical applications for superconductors from the medical field, through power transmission and storage to transportation, with impacts whenever electricity is used.
Superconductivity as a means to improve power generation, storage and transmission is not a new idea, but it requires further research and development to become widespread before room temperature superconductivity becomes a reality. The capacity for zero electrical resistance means energy can be generated, transmitted and stored with no loss—an enormous low-cost advantage. However, current technology demands that the superconducting device be kept at severely low temperatures to retain its unique state, which still requires additional energy as an overhead cost, not to mention the potential hazard of the accidental failure of the cooling system. Hence, an RTS superconductor with no extra pressure to sustain its beneficial properties is a necessity to move forward with more practical applications.
The properties of superconductivity are also paving the way for a competitor to the famous bullet train seen throughout East Asia: a maglev train. Short for “magnetic levitation,” the first maglev train built in Shanghai in 2004 successfully broadened usage in Japan and South Korea and is under consideration for commercial operation in the US. At top speeds of 375 miles per hour, cross country flights see a quick competitor in the maglev train. A room temperature superconductor could help Elon Musk realize his dream of a “hyperloop” to travel at a speed of 1000 miles per hour.
This successful implementation of the PQ technique on room temperature superconductors discussed in Chu and Deng’s paper is critical in making superconductors possible for ubiquitous practical applications.
Now the riddle of RTS at ambient pressure is even closer to being solved.
Researchers discover unusual competition between charge density wave and superconductivity
More information:
Liangzi Deng et al, Pressure-induced high-temperature superconductivity retained without pressure in FeSe single crystals, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2108938118
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In what sounds like it will be a joint effort, Orlando area theme parks will be reducing COVID-19 safety protocols.
Walt Disney World Resort was the first to make the move, announcing that they will be removing mandatory temperature checks from theme park entrances and more, beginning for cast members on May 8th and then for guests on May 16th.
The Orange County Department of Health stated on April 30th that temperature checks were no longer needed for businesses, and in fact were a waste of resources.
Temperature checks have been required at the Walt Disney World Resort theme parks since they reopened in July 2020, and they have been in place at Disney Springs since it reopened in May 2020.
Navalny went on hunger strike last week to protest against prison officials’ refusal to grant him access to proper medical care. He had been suffering from acute back pain that had affected his ability to walk and his condition was being exacerbated by alleged “torture by sleep deprivation,” one of his lawyers said last month.
Navalny said the prison didn’t have the sustenance and nutrients required to keep inmates healthy, adding his temperature was recorded as 38.1 degrees Celsius (100.6 Fahrenheit) and that he had a severe cough.
In the post on Monday, Navalny also said there was a tuberculosis outbreak amongst his cellmates, with three out of the group’s 15 prisoners recently hospitalized with the disease.
“And what? Do you think there is a state of emergency, ambulance sirens are blaring? No-one cares, the bosses are worried only about how to hide the statistics,” Navalny said in the post.
A prominent opposition-linked doctors’ union, Doctors’ Alliance, scheduled a protest in support of Navalny on Tuesday outside the penal colony No.2 in Pokrov, where the Kremlin critic is being held. The group is run by an ally of Navalny who said the protesters will demand proper medical attention for the opposition figure.
‘Practically exemplary’ penal colony
In the post shared on Monday, Navalny also criticized Russian state media’s recent coverage of conditions inside the penal colony.
Last week, a film crew from Russia’s state-controlled TV network RT visited the prison with Maria Butina, a Russian gun-rights enthusiast-turned TV personality who now works for the network. The report said the prison was “practically exemplary.”
Butina was convicted of conspiring to act as an agent for a foreign state in the United States and served more than 15 months behind bars in Florida. She pleaded guilty of trying to infiltrate conservative political circles and promote Russian interests before and after the 2016 presidential election.
Navalny pushed back against RT’s assessment of the conditions.
“This is what our ‘ideal, exemplary colony’ looks like. Any prisoner prays to God not to get here, but inside there are unsanitary conditions, tuberculosis, lack of medications. Looking at the awful plates, in which they put our gruel, I am generally surprised that there is no Ebola virus here yet,” Navalny said in the Instagram post on Monday.
“I have a legally guaranteed right to invite a specialist doctor at my own expense. I will not give it up, prison doctors can be trusted just as much as state TV,” he added.
Navalny, a long-time critic of President Vladimir Putin, was jailed earlier this year for violating the probation terms of a 2014 case in which he received a suspended sentence of three and a half years. A Moscow court took into account the 11 months Navalny had already spent under house arrest as part of the decision and replaced the remainder of the suspended sentence with a prison term last month.
A man who was arrested after refusing a temperature screening at Disney Springs told authorities he couldn’t be told to leave because he spent $15,000 on his vacation.
Kelly Sills, a tourist from Baton Rouge, Louisiana, bypassed the Orlando attraction’s medical screening in February and refused to get his temperature checked when asked by Disney employees, according to a police report from the Orange County Sheriff’s Department.
Body camera footage recently released showed Sills refusing to leave when asked by law enforcement.
“I spent $15,000 to come here,” Sills said after a deputy told him he was officially considered to be trespassing. Deputies and a security manager at Disney Springs had approached Sills outside the Boathouse restaurant, according to the police report.
Sills allegedly argued with the security manager, yelling at him, before the manager told him he was “no longer welcome at the park today,” the report said.
A woman could be heard asking officers not to arrest Sills in the body camera footage.
“He’s not listening,” a man responded. “All he had to do was get temperature checked. That’s it.”
At another point in the video, Sills asked whether authorities could take his temperature before forcing him to leave. Someone responded that they would do so at jail, according to NBC affiliate WFLA. Sills also claimed to be a Disney stockholder at another point.
Sills pleaded not guilty to a misdemeanor trespassing charge, according to court records. His attorney, Michael Zmijewski, declined to comment on the case to NBC News Sunday.
Doha Madani is a breaking news reporter for NBC News.
Some of the deepest parts of the Black Sea are still responding to climate changes prompted by the last ice age, scientists have discovered – a period which officially ended almost 12,000 years ago.
An analysis of gas hydrate deposits – in this case methane trapped by water molecules, in a solid substance that looks like ice – has revealed the lagging response in a northwestern area of the Black Sea known as the Danube fan.
Together with temperature measurements and other data, the drill cores of the gas hydrate deposits reveal something rather surprising: Levels of free methane gas under the seafloor have not yet adapted to the warmer conditions that have already prevailed on the surface for thousands of years.
“This shows that the gas hydrate system in the Danube deep sea fan is still responding to climate changes initiated at the end of the last glacial maximum,” write the researchers in their paper.
Examining drill cores. (Christian Rohleder)
Central to the findings are scientists’ attempts to determine the base of the gas hydrate stability zone (GHSZ) – the lowest point at which gas hydrates naturally form due to temperature, pressure, and a few other factors. Above and below that zone, you’ll get ‘free’ methane gas not trapped in hydrates.
To find the base of this zone, researchers typically turn to a seismic reflection measure of the sediment known as the bottom-simulating reflector, or BSR for short. However, earlier work has found that in this part of the Black Sea, there’s a curious depth discrepancy between the BSR and the base of the gas hydrate stability zone.
By drilling down to the seafloor and taking temperature measurements, researchers have now concluded that the gas hydrate stability zone has adapted to the warmer conditions over the past millennia – as indicated by a rise to a higher level – but the free methane gas and the associated BSR are still playing catch up.
“From our point of view, the gas-hydrate stability boundary has already approached the warmer conditions in the subsurface, but the free methane gas, which is always found at this lower edge, has not yet managed to rise with it,” says geophysicist Michael Riedel, from the GEOMAR Helmholtz-Center for Ocean Research in Germany.
That lagging response could be why the BSR isn’t where it should be. Sediment permeability could also play a role, the team thinks, and their measurements show that methane has managed to rise in certain areas but not others.
“In summary, we have found a very dynamic situation in this region, which also appears to be related with the development of the Black Sea since the last ice age,” says Riedel.
Around 20,000 years ago, the water level was around 100 meters (328 feet) lower in the Black Sea, meaning less pressure on the sea bed. The water was significantly cooler too. As far as the free methane gas is concerned, those conditions haven’t yet changed.
As with any study of the effects of climate change, this research is going to help in future climate modeling. There’s currently a huge volume of gas hydrate deposits underneath the Arctic, for instance, and it’s important to know how they might react to increases in temperature in the years ahead.
The scientists emphasize that their findings should be interpreted cautiously, with many different factors in play and plenty more scope for study – but they also stress the importance of in-situ measurements and quality data for an analysis such as this.
“For our investigations we used our drilling device MARUM-MeBo200 and broke all previous depth records with a maximum depth reached of almost 145 meters [476 feet],” says geologist Gerhard Bohrmann, from the University of Bremen in Germany.
The research has been published in Earth and Planetary Science Letters.
