Tag Archives: co2

Liquid cerium catalyst.

New process could capture CO2 and make it coal again

Instead of burning coal and releasing CO2, new research plans to absorb CO2 and produce coal.


Image via Pixabay.

A new breakthrough could allow us to burn our coal and have it, too. Researchers from Australia, Germany, China, and the US have worked together to develop a carbon storage method that can turn CO2 gas into solid carbon particles with high efficiency. Their approach could help us scrub the atmosphere of (some of) the greenhouse emissions we produce — with a certain dash of style.

Coal idea

“While we can’t literally turn back time, turning carbon dioxide back into coal and burying it back in the ground is a bit like rewinding the emissions clock,” says Torben Daeneke, an Australian Research Council DECRA Fellow and paper co-author.

The idea of permanently removing CO2 from the atmosphere isn’t new — in fact, it’s heavily considered as a solution to our self-induced climate woes. We’ve developed several ways to go about it, but they simply aren’t viable yet. Current carbon capture technologies turn the gas into a liquid form, which is then carted away to be injected underground. However, the process requires high temperatures (which means high costs) and there are environmental concerns regarding possible leaks from storage sites.

The team’s approach, however, relies on an electrochemical technique to capture atmospheric CO2 and turn it into solid, easy to store carbon.

“To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially unviable,” Daeneke explains. “By using liquid metals as a catalyst, we’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scalable.”

“While more research needs to be done, it’s a crucial first step to delivering solid storage of carbon.”

The liquid metal cerium (Ce) catalyst has certain surface properties that make it a very good electrical conductor — the current also chemically activates the catalyst’s surface.

Liquid cerium catalyst.

Schematic of the catalytic process.
Image credits Dorna Esrafilzadeh, (2019), Nature.

The whole process starts with the team dissolving carbon dioxide gas in a liquid-filled beaker and a small quantity of the liquid metal. When charged with electrical current, this catalyst slowly starts converting the CO2 into solid flakes of carbon on its surface and promptly falls off, so the process can be maintained indefinitely.

“A side benefit of the process is that the carbon can hold electrical charge, becoming a supercapacitor, so it could potentially be used as a component in future vehicles,” says Dr Dorna Esrafilzadeh, a Vice-Chancellor’s Research Fellow in RMIT’s School of Engineering and the paper’s lead author.

“The process also produces synthetic fuel as a by-product, which could also have industrial applications.”

The paper “Room temperature CO2 reduction to solid carbon species on liquid metals featuring atomically thin ceria interfaces” has been published in the journal Nature.


New design hotfix could make artificial leaves better than actual leaves

A new design could bring artificial leaves out of the lab to convert CO2 into raw materials for fuel.


Image credits Jeon Sang-O.

The idea behind artificial leaves isn’t very complicated — just make them do the same job regular leaves perform, but faster, if possible. Despite this, we’ve had a hard time actually delivering on the idea outside of laboratory conditions. New research, however, could improve on the technology enough to make it viable in the real world.

Leaf it to the catalysts

The sore point with our present artificial leaves is that they simply don’t gobble up CO2 at the concentrations it’s found in the atmosphere.

“So far, all designs for artificial leaves that have been tested in the lab use carbon dioxide from pressurized tanks. In order to implement successfully in the real world, these devices need to be able to draw carbon dioxide from much more dilute sources, such as air and flue gas, which is the gas given off by coal-burning power plants,” said Meenesh Singh, assistant professor of chemical engineering in the UIC College of Engineering and corresponding author on the paper.

While artificial leaves are meant to mimic photosynthesis, even our most refined leaves only work if supplied with pure, pressurized CO2 from tanks in the lab. It’s good that they work, it means we’re on the right track, but they’re not useable in practical applications. Because they only work with high concentrations of CO2, they can’t be used to scrub this gas out of the wider atmosphere, which is what we want to do with them.

Researchers at the University of Illinois at Chicago, however, propose a design solution that could fix this shortcoming. Their relatively simple addition to the design would make artificial leaves over 10 times more efficient than their natural counterparts at absorbing CO2. The gas can then be converted to fuel, they add.

Singh and his colleague Aditya Prajapati, a graduate student in his lab, say that encapsulating artificial leaves inside a transparent, semi-permeable capsule filled with water is all we need to do. The membrane allows water inside to evaporate which, as it passes through the quaternary ammonium resin membrane, pulls in CO2 from the air.

Artificial leaf.

A schematic showing the main principles behind this process.
Carbon dioxide (red and black) enters the leaf as water (white and red) evaporates from the bottom of the leaf. An artificial photosystem (purple circle at the center of the leaf) made of a light absorber coated with catalysts converts carbon dioxide to carbon monoxide and converts water to oxygen (double red spheres) using sunlight.
Image credits Meenesh Singh.

The artificial photosynthetic unit inside the capsule then converts carbon dioxide to carbon monoxide, which can be siphoned off and used to make fuel. Oxygen is also produced and can either be collected or released into the surrounding environment.

“By enveloping traditional artificial leaf technology inside this specialized membrane, the whole unit is able to function outside, like a natural leaf,” Singh said.

The duo estimates that 360 such leaves, each measuring 1.7 meters by 0.2 meters (5.5 by 0.6 feet), could produce around half a ton of carbon monoxide per day. Spread over a 500 sq meter area, the leaves could reduce CO2 levels by 10% within 100 meters of the array in a single day, they add.

“Our conceptual design uses readily available materials and technology, that when combined can produce an artificial leaf that is ready to be deployed outside the lab where it can play a significant role in reducing greenhouse gases in the atmosphere,” Singh said.

The paper “Assessment of Artificial Photosynthetic Systems for Integrated Carbon Capture and Conversion” has been published in the journal ACS Sustainable Chemistry & Engineering.

CO2 emissions.

Atmospheric greenhouse gas levels hit new record. Just like in 2017… and 2016

Greenhouse gases in the atmosphere have hit a record high — again.

CO2 emissions.

Image credits Climate and Ecosystems Change Adaptation Research University Network / Flickr.

United Nations (UN) officials reported last week that greenhouse gas concentrations in the atmosphere have hit a record high. The report, published in preparation for the COP24 climate summit to be held in Poland next month, also warns that the time to act is running short.

Too much bad gas

“Without rapid cuts in CO2 and other greenhouse gases, climate change will have increasingly destructive and irreversible impacts on life on Earth,” the head of the World Meteorological Organization Petteri Taalas said in a statement.

“The window of opportunity for action is almost closed.”

The Greenhouse Gas Bulletin — the flagship annual report of the UN’s weather agency, WMO (World Meteorological Organization) — has been tracking the content of various gases in the atmosphere since 1750. This year’s report (covering data for 2017), puts CO2 content in the atmosphere at 405.5 ppm (parts per million). This is the single highest value we’ve ever seen during our time on the planet — it’s up from 403.3 ppm in 2016 and 400.1 ppm in 2015. Both years were record-setters in the CO2-content department themselves.

However, it’s not the first time our planet has experienced such levels of carbon dioxide. The WMO has reliable CO2 concentration estimates for the last 800,000 years, drawn from analysis of air bubbles locked in the ice sheets of Greenland or Antarctica. It also has rough estimates of the gas’ concentration in our atmosphere spanning the last five million years, mostly drawn from chemical analysis of fossils.

“The last time the Earth experienced a comparable concentration of CO2 was 3-5 million years ago, when the temperature was 2-3°C warmer,” Taalas said.

The agency also points to rising concentrations of methane, nitrous oxide, and ozone-depleting gases (such as CFC-11) in addition to CO2. Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) all broke new records in 2017, with CO2 at 405.5 ppm, CH4 at 1859 ppm, and N2O at 329.9 ppb. These values represent, respectively, 146%, 257%, and 122% of pre-industrial (before 1750) levels.

We need to scrub

All in all, this isn’t good news. While the amount of greenhouse gas in the atmosphere is indeed a direct consequence of emissions, that’s only part of the picture. Emissions are how much of such compounds we release into the wild; the levels reported on by the WMO are what stays there after plants, oceans, and all sorts of other players are done absorbing their share. ‘Their share’ amounts to roughly 25% of all emissions for oceans and the biosphere, plus a little extra that goes into the lithosphere (i.e. rocks) and cryosphere (i.e. ice).

These atmospheric concentrations reported on by the WMO are, then, the year-after-year build-up of emissions that our planet can’t process. According to the UN’s Intergovernmental Panel on Climate Change (IPCC), the body tasked with reviewing climate science and organizing the international effort against climate change, net emissions must be brought to zero in order to limit warming to below 1.5°Celsius.

This basically means either not emitting anything in the first place (which is highly unlikely to happen right now), or scrubbing as much greenhouse gas out of the air as we put out — whether this is done through natural or technological means isn’t really important. If we can’t rise up to the challenge, notes WMO’s deputy chief, Elena Manaenkova, all that CO2 will end up in the atmosphere and oceans — and plague us for hundreds of years. To put it in context, the cost of climate-related disasters topped $2.25 trillion worldwide from 1998 to 2017. The U.S. had “the worst” losses with $944.8 billion, followed by China with $492.2 billion, and Japan with $376.3 billion, Niall McCarthy writes for Forbes. The UN reports that 17 of the 18 hottest years on record have occurred since 2001. A warmer climate means more and more powerful disasters (such as droughts, storms, or disease).

“There is currently no magic wand to remove all the excess CO2 from the atmosphere,” she said. “Every fraction of a degree of global warming matters, and so does every part per million of greenhouse gases,” she said.

UN rights chief Michelle Bachelet warned in an open letter addressed to all member states at COP24 that the world faces dire consequences if we don’t change our ways. “Entire nations, ecosystems, peoples, and ways of life could simply cease to exist,” she said. She cited evidence that nations are not on track to meet the commitments made in Paris in support for her claims.

In response to a recent tweet from US president Donald Trump — “Brutal and Extended Cold Blast could shatter ALL RECORDS – Whatever happened to Global Warming?” — deputy WMO chief Elena Manaenkova chose to simply tell reporters that the science on global warming is “unequivocal.”


The report “WMO Greenhouse Gas Bulletin (GHG Bulletin) – No. 14: The State of Greenhouse Gases in the Atmosphere Based on Global Observations through 2017” is available on the WMO’s page here.


Researchers hack corn to grow fatter and absorb more carbon dioxide

An international team of researchers wants to level up corn by boosting its ability to capture CO2 from the atmosphere.


Image credits Juraj Varga.

Corn (or maize) is a fruit and one of the most important staple foods on the planet, exceeding even rice or wheat in quantity grown per year. However, in Australia, while corn has the widest geographical spread of all field crops, it lags behind its counterparts (such as wheat or rice) in yield.

One of the main issues maize has to grapple with in the land down under are harsh environmental conditions. In a bid to help the crop bloom to its full potential, an international team of researchers has been toying with its genome, to boost the plant’s ability to photosynthesize.

Sunny maize

“We developed a transgenic maize designed to produce more Rubisco, the main enzyme involved in photosynthesis, and the result is a plant with improved photosynthesis and hence, growth. This could potentially increase tolerance to extreme growth conditions,” said lead researcher Dr. Robert Sharwood from the ARC Centre of Excellence for Translational Photosynthesis, led by The Australian National University (ANU).

While all plants rely on photosynthesis to capture carbon dioxide from the atmosphere, they go about it in different ways. Plants like wheat and rice use an older and less efficient photosynthetic path (the ‘C3’ path), while other plants such as maize and sorghum use the more efficient C4 path.

Some of the most important food crops today (as well as many that are used for animal feed and biofuel production) rely on the C4 pathway. C4 plants are specially adapted to thrive in hot and dry environments — ones that are expected to be more prevalent in future decades.

“There is an urgent need to deliver new higher-yielding and highly adapted crop species, before crops are affected by the expected climate change conditions. These conditions will increase the threats against global food security, and the only way to prepare for them is through international research collaborations.”

One of the molecules that underpins photosynthesis is an enzyme known as Rubisco — which converts CO2 into organic compounds. Rubisco’s activity is much improved in C4 plants, making the process faster and more water-efficient. As a result, these plants are more tolerant to heat and drought, and tend to be more productive than their C3 counterparts. Maize has one of the most efficient Rubisco enzymes and uses “less nitrogen” to grow than other crops.

“So, our main question was, if we increase Rubisco content in maize, what would it do for the plant?” says co-author David Stern, from the Boyce Thompson Institute.

“We found that by boosting Rubisco inside the maize cells, we get an increase in crop productivity,”

Overall CO2 assimilation and crop biomass increased by 15%, the team reports. While quite excited with their results so far, the researchers plan to further increase the “pool of active Rubisco” in the plant to increase this percentage even further. Until then, however, they hope to pit their maize against real-field conditions — the crop has, thus far, only been tested in glasshouse and cabinet conditions.

However, if the team’s maize proves itself hardy enough to survive farmland, it could pave the way for further C4 crop species to receive the same treatment.

The paper “Overexpression of Rubisco subunits with RAF1 increases Rubisco content in maize” has been published in the journal Nature Plants.

Rice is losing its nutritional value due to rising CO2 levels

Increasing carbon dioxide levels in the atmosphere due to human activity are lowering the nutritional value of rice, according to a new study published in Science Advances. 

Credit: Pixabay.

After wheat, rice is the second most important food crop in the developing world. Over two billion people in Asia and hundreds of millions in Africa and Latin America depend on rice for their daily calorie needs. It’s estimated that more than 40,000 varieties of cultivated rice (the grass species Oryza sativa) exist.

Rice is also an important source of protein and vitamins, which is why the latest findings by researchers at the University of Tokyo are so worrisome. Their experiments suggest that rising CO2 levels in the atmosphere are lowing the nutritional value of rice, specifically iron, zinc, protein, and vitamins B1, B2, B5, and B9.

The team grew rice at sites in China and Japan using an open-field method called FACE (free-air CO2 enrichment). Professor Kazuhiko Kobayashi and colleagues at the University of Tokyo decided to grow the rice in an open field because plants raised in a closed greenhouse do not grow as they would in normal field conditions. Air with higher carbon dioxide concentrations, as expected in the second half of this century (568 to 590 parts per million), was blown through 17-meter-wide (56-foot-wide) plastic pipe octagons at about 30 centimeters (1 foot) above the tops of plants within standard rice fields.

In total, the researchers analyzed 18 different varieties of rice for protein, iron, and zinc levels. Nine varieties of rice grown in China were used for the vitamin B1, B2, B5, and B9 analyses.

Experimental rice field near Tsukuba, Japan.Dr. Toshihiro HASEGAWA (National Agriculture and Food Research Organization of Japan).

Experimental rice field near Tsukuba, Japan.Dr. Toshihiro HASEGAWA (National Agriculture and Food Research Organization of Japan).

The two FACE experiments have provided a unique opportunity to investigate how a crop fares in response to predictably elevated levels of CO2 in the atmosphere. But like with any other unique science experiment, the Japanese researchers had to overcome some challenges, including the presence of uninvited guests.

“The unique experiments attracted other species. An example was raccoons in my own experience. We did the FACE experiment in farmer’s fields, where we installed plastic tubes to sample air from the field and measure CO2 concentrations in the experimental plots. Raccoons came out of the nearby mountains at night and tested the strength of their teeth against the plastic tubes. They eventually cut the air sampling tubes, which fell into the flooded water in the rice field jeopardizing our experiment. We then had to raise the tubes higher than their reach. The higher CO2 concentrations in the experimental plots also attracted blood-sucking insects, which we had to fight against while working in the plots,” Kobayashi told ZME Science.

Little is known about the mechanisms responsible for the decline in nutrient concentrations associated with elevated CO2. Some authors have proposed “carbohydrate dilution” whereby CO2-stimulated carbohydrate production by plants dilutes the rest of the grain components, but studies so far have been inconclusive. What’s certain is that it’s happening.

In many countries, rice is so important that they’re literally synonymous with food. The Chinese word for rice is the same as the word for food, in Thailand when you call your family to a meal you say, “eat rice”, and in Japan, the word for cooked rice is the same as the word for meal.

The Japanese don’t consume as much rice as they used to during the 1960s, for instance, relying on only about 20 percent of their daily calorie intake from the crop. However, people in Bangladesh, Cambodia, Indonesia, Lao People’s Democratic Republic, Myanmar, Vietnam, and Madagascar who receive at least 50 percent of their calories and protein from rice are the most vulnerable to poorer nutritional content.

Zinc deficiency is already linked to around 800,000 deaths among under-fives, in whom it can seriously exacerbate such conditions as diarrhea, pneumonia, and malaria, while iron deficiency is the main cause of anemia, a condition that contributes to around one in every five maternal deaths around the world.

“Our finding has demonstrated another reason why we have to be concerned about the nutrition for the poorer fractions of the population in less developed countries. Any measures to improve their nutrition would effectively alleviate the negative effects of the lower nutrient content under higher CO2 level. The measures could be better policies and/ or better varieties, but must reach the target population,” Kobayashi wrote in an e-mail.

As the world’s population continues to swell, not only will developing countries have to grow more rice and improve their yield, they will also have to find ways to offset the poorer nutritional value of the crops. Of course, rice won’t be alone. Previous studies have found that rising levels of carbon dioxide in the atmosphere reduce the nutritional value of other staple crops, such as wheat or soy.

“This is one of the multitudes of challenges of climate change due to the energy production based on fossil fuel burning. We, in the so-called developed countries, take advantage of the fossil fuel energies, while having little troubles with the less nutritious grains, because we take the nutrients from other food stuffs. On the other hand, those in the less-developed countries depend grains for their nutrient intake, and would be affected by the changes in grain nutrient content. And, they are much less responsible for the climate change than we are on per person basis. This is really a shame on us, I think,” Kobayashi concluded.

Scientific reference: C. Zhu, K. Kobayashi, I. Loladze, J. Zhu, Q. Jiang, X. Xu, G. Liu, S. Seneweera, K. L. Ebi, A. Drewnowski, N. Fukagawa, L. H. Ziska, Carbon dioxide (CO2) levels this century will alter the protein, micronutrients, and vitamin content of rice grains with potential health consequences for the poorest rice-dependent countries. Sci. Adv. 4, eaaq1012 (2018).

Trump Administration shuts down CO2 monitoring program, as greenhouse gas levels skyrocket

The Trump Administration just castrated an important carbon monitoring program run by NASA — just as the ever increasing CO2 levels that have surpassed a new alarming threshold.

Weather stations at the Mauna Loa Observatory in Hawaii registered CO2 levels constantly above 410 parts per million (ppm) throughout the whole month of April. Just a year ago, the station recorded the first blip over 410 ppm. The last time CO2 levels were this high was about 3.6 million years ago, during the mid-Pliocene warm period. Today, that’s new normal. Back then, Earth’s sea levels were roughly 20 meters (66 feet) higher than today and the atmosphere was a lot warmer. The big difference is that we’ve moved towards mid-Pliocene CO2 levels in the span of less than a century, whereas 3 million years ago CO2 levels were sustained over far longer periods of time.

NASA’s Carbon Monitoring System (CMS) costs about $10 million but with this relatively modest budget (approximately equivalent to a US production tank), scientists were able to monitor the flow of carbon across the entire planet. The program tracks not only the sources of carbon and its movement around the atmosphere but also carbon sinks (oceans and forests), where some of it is eventually sucked in and deposited. For instance, the U.S. Forest Service used data amassed by the CMS to conduct inventories of carbon stocks within Alaska’s remote interior. In total, at least 65 different projects have directly benefitted from CMS data.

In the absence of CMS, it will be very difficult now for scientists to assess the efficacy of cutting emissions at the national level, among other things. Being unable to accurately measure emissions means the country will face difficulty meetings it Paris Agreement pledge, which entails reducing emissions by 26–28% of 2005 levels by 2025. That probably doesn’t bother the current administration one bit seeing how it started the procedure to withdraw the US from the agreement. 

Withdrawing CMS funding is the latest in a string of White House executive decisions meant to undermine NASA’s Earth Science programs, many of which are important to climate research. Government spokesperson Steve Cole attributed the project’s scrapping to “budget constraints and higher priorities within the science budget.” However, according to Kelly Sims Gallagher, director of Tufts University’s Center for International Environment and Resource Policy in Medford, Massachusetts, the move may actually be intended to jeopardize plans to verify the national emission cuts agreed to in the Paris climate accords.

 “If you cannot measure emissions reductions, you cannot be confident that countries are adhering to the agreement,” she told Scienceadding “[canceling the CMS] is a grave mistake.”

The timing could not have been worse. NASA is preparing to launch several space-based carbon trackers, including the OCO-3, which is set to be mounted on the International Space Station later this year. The CMS program would have been an important component that bridged all of these observations, providing a better overview.

The good news is that all of this doesn’t mean that the world is at risk of inaccurately measuring carbon in the atmosphere from now on. As it so happens in similar situations since President Trump came to office, Europe is prepared to take over the reins and assume a leadership position. The world won’t end tomorrow. But it’s just a shame to see CMS go when common sense said it was doing so much good — a damn shame.

Apollo Beach power plant.

Average atmospheric CO2 levels last month were the highest we’ve ever recorded, ever

Atmospheric concentrations of carbon dioxide have set a new and worrying record: for the first time in recorded history, levels averaged higher than 410 parts per million (ppm) throughout the whole month.

Apollo Beach power plant.

Apollo Beach power plant.
Image via Wikimedia.

Last year, CO2 levels in the atmosphere hit the highest concentration they’ve reached in millions of years — 410 ppm. It wasn’t a pretty sight, and it was a testament to humanity’s advancements: for better or worse, we had become a geological force.

This April, we’ve reached an even more ignoble record: we’ve seen average atmospheric CO2 levels rise above the 410 ppm mark and stay there throughout the whole month for the first time in history.

A worrying development

“We keep burning fossil fuels. Carbon dioxide keeps building up in the air. It’s essentially as simple as that,” says Scripps Institution of Oceanography geochemist Ralph Keeling.

When it comes to atmospheric CO2 levels, Keeling is the guy to talk to. You could say he was born and bred for it — the chart we use to keep track of these levels, the Keeling Curve, is based on the work of the late Charles David Keeling, Ralph’s father. It was this curve that first hinted to the possibility of anthropogenic contribution to the greenhouse effect and global warming.

The readings on which the Keeling Curve is based first began at the Mauna Loa Observatory in 1958. At the time, measurements indicated a CO2 concentration of roughly 315 ppm. Just 60 years later, we’ve passed the 410 ppm threshold. This April, the average concentration was 410.31 ppm, according to data published by the Scripps Institution of Oceanography.

This is the first time in the observatory’s history that a monthly average exceeded 410 ppm, the institution adds.

It’s not, strictly speaking, the first time atmospheric CO2 levels have reached 400 ppm. We know of at least one previous case where it happened — we call it the Pliocene warm period, and it lasted from around 5.3 to 2.6 million years ago. What was going on during that time? So glad you asked.

Earth in the mid-Pliocene doesn’t seem very different from that of today at first glance — in general, it was 2 to 3°C warmer than nowadays. Carbon dioxide levels were, again, about the same as today. The seas, however, not so much — the global sea level was about 20 to 25m higher than it is today. The Northern hemisphere couldn’t maintain almost any permanent ice sheets up until very near the end of the Pliocene, around 3 million years ago, and all that liquid water swelled the oceans.

Other things the Pliocene lacked in spades were coastal cities, globalized economies, or masses of people to suffer from the environmental damage.

What’s particularly worrying for researchers today isn’t the CO2 concentrations themselves — it’s how fast we’re increasing them. The Pliocene level “was sustained over long periods of time, whereas today the global CO2 concentration is increasing rapidly,” according to scientists in the Fourth National Climate Assessment, Volume 1, a federal report published last year.

Before the Industrial Revolution, CO2 levels fluctuated very slowly, over thousands of years. According to researchers at the Scripps Institute, however, these levels never once exceeded 300 ppm once in the past 800,000 years. Around 1880, CO2 levels peaked at about 280 ppm. That makes today’s levels a staggering 46% higher than those just over a century ago.

“It’s as if we discovered that something we eat every day is causing our body to run a fever and develop all kinds of harmful symptoms — and instead of cutting back, we right keep on eating it, more and more,” tweeted climate scientist Katharine Hayhoe about the findings.

“If that isn’t alarming, I don’t know what is.”

How Roman priests walked through the “Gates to Hell” — and came back

Romans staged elaborate sacrificial rituals in which castrated priests walked through the “Gates to Hell,” carrying with them healthy bulls. The priests would return unscathed, while the sacrificial animals would succumb to the Gods. Now, a new study has found the secret to this ancient ritual.

Roman ruins at Hierapolis. Image credits: Kisch / Wikipedia.

The Gate to Hell

In 2013, archaeologists made an intriguing discovery in the Greco-Roman city of Hierapolis, now in modern-day Turkey. Known as Pluto’s Gate, or Ploutonion in Greek, the cavern was a gate to the underworld.

Archaeologists dug up its temple, pool, and steps leading down to the ceremonial cave, all matching ancient historical depictions of the place.

Back in the Ancient times, the Greek geographer, philosopher, and avid traveler Strabo, (64/63 BC to 24 AD) described it thusly:

“This space is full of a vapor so misty and dense that one can scarcely see the ground. Any animal that passes inside meets instant death. I threw in sparrows and they immediately breathed their last and fell.”

Strabo also described how sacrificial rituals were carried at the site. Castrated priests would be left unharmed, while animals were killed without any human intervention. There’s no reason to doubt his and others’ recollection of the events. But what was really happening there?

Ruins of the temple around the grotto. Image credits: Ömerulusoy / Wikipedia.

Geology and magic

Hierapolis itself lies in a geologically active area. Its geothermal waters were a major attraction, with many people believing they have magical healing powers. But beneath the city, a massive fissure (the Babadag fracture zone) leaks volcanic carbon dioxide, which is barely visible as a mist. The same phenomenon is happening today.

Volcano biologist Hardy Pfanz at the University of Duisburg-Essen in Germany wanted to measure these emissions, so he took a portable gas analyzer system to map the CO2 concentration at the ancient temple. In the study, he writes:

“The concentrations of CO2 escaping from the mouth of the grotto to the outside atmosphere are still in the range of 4–53% CO2 depending on the height above ground level. They reach concentrations during the night that would easily kill even a human being within a minute.”

He goes on to say that this could easily be understood as the door to the underworld.

“These emissions are thought to reflect the Hadean breath and/or the breath of the hellhound Kerberos guarding the entrance to hell.”

The CO2 concentration 40 centimeters above the arena floor reaches 35% — more than enough to asphyxiate animals or even humans. However, the concentration falls rapidly with height. This means that the priests were simply tall enough, their noses being above the CO2 blanket, where the air was safe to breathe.

But they also had a few other tricks up their sleeves. While Strabo believed their ability to survive the grotto was owed to their castration, Pfanz believes the priests were aware of the nature of the environment.

Strabo also wrote that priests only went in a bit far in the cave, and sometimes held their breath. As the animals got dizzier and dizzier, they would let their heads more and more down — but priests would pay attention and keep their heads up. Pfanz also learned that the carbon dioxide concentration varies with the time of day. So sacrifices would be carried out during the morning or evening hours when the concentration of the gas was highest. But outside of the sacrifices, the priests would stay well away from the cave, only coming close during noon, when levels were at their lowest. Even today, emissions are still dangerous, as archaeologists reported that several birds and other small animals were unfortunate enough to venture over the emissions zone, and fell to its effects.

It’s wonderfully exciting that researchers were able to bring together so many different aspects of science. Linking modern chemistry to ancient rituals and archaeology is exciting and opens up a unique window to the past. Just imagine, the priests had at least some idea of what was going around, but for the average viewer, you would be witnessing the Gods in action, taking the soul of the unfortunate sacrifice. It must have been a hell of a show.

Journal Reference: Hardy Pfanz, Galip Yüce, Ahmet H. Gulbay, Ali Gokgoz. Deadly CO2 gases in the Plutonium of Hierapolis (Denizli, Turkey).

scorched ground

Every other summer expected to break heat records by 2030

By the next decade, every second summer will likely be record-setting hot — hotter than any summer before it in the past 40 years. What’s more, if today’s warming trend continues unabated, by 2050, virtually every subsequent summer will be the ‘hottest ever’.

scorched ground

Credit: Pixabay.

Already, the last couple of years this decade have been unusually hot. It’s tiring to report how almost every year is ‘the hottest yet’ or at least features a ‘record-breaking hot summer’. Although it’s not even over, 2017 is set to be one of the hottest three years on record, according to the World Meteorological Organization (WMO).

“The past three years have all been in the top three years in terms of temperature records. This is part of a long term warming trend. We have witnessed extraordinary weather, including temperatures topping 50C in Asia, record-breaking hurricanes in rapid succession in the Caribbean and Atlantic reaching as far as Ireland, devastating monsoon flooding affecting many millions of people and a relentless drought in East Africa,” Petteri Taalas, secretary general of the WMO, told The Guardian earlier this month.

Now, a new study published in the journal Earth’s Future suggests such news will become yearly mundanities. According to Francis Zwiers, director of the Pacific Climate Impacts Consortium at the University of Victoria, Canada, and his colleagues, record hot summers are now 70 times more likely than they were in the past 40 years over the Northern hemisphere. As a result, heat waves will intensity and more people will risk losing their lives. A different study published in 2017 estimates a 50-fold increase in lives lost due to freak weather in the old world, from 3,000 today (mean average between 1981-2010) up to 152,000 by 2100.

Zwiers’ team employed a ‘fingerprint’ analysis that compares climate models and observational records for temperature and humidity over the past 40 years. Their analysis suggests with “95 percent confidence” that man-made CO2 emissions and other greenhouse gases like methane are the primary cause for the huge uptick in hot summers. Today, CO2 levels in the atmosphere are 44 percent higher than they were 150 years ago.

This is just the most recent study from a long list of research that found upcoming years will only get hotter and hotter. Another study published in Nature Climate Change found that about 30 percent of the world’s population is already vulnerable to life-threatening heat waves for 20 days a year. By 2010, three in every four people could be exposed deadly heatwaves. This, along with other dire consequences like sea level rise and more frequent extreme weather, unless the world urgently puts the breaks on fossil fuels and greenhouse gas emissions.

Even though overall CO2 emissions have been relatively flat from 2014 to 2016, atmospheric concentrations saw a record increase in 2015 and 2016 (bars) due to El Niño conditions. Scientists expected CO2 emissions to grow in 2017 (red dots), but they expected the growth in atmospheric concentrations (red bar) to be lower in 2017 compared to 2015 and 2016, in the absence of an El Niño event. Credit: Nature Climate Change.

After three flat-line years, global carbon emissions are back on the rise

From 2014 to 2016 man-made CO2 emission growth entered a hiatus, although the economy was, and still is, on an upward trend. Some had hoped this three-year flatline signified a turning point in history, when humanity peaked fossil fuel use. Alas, it was not to be. Reporting from Bonn, Germany, where world leaders gathered at the same COP conference where the now-famous Paris Agreement was signed, scientists working at the Global Carbon Project claim that CO2 emissions are projected to rise to a record high in 2017.

Even though overall CO2 emissions have been relatively flat from 2014 to 2016, atmospheric concentrations saw a record increase in 2015 and 2016 (bars) due to El Niño conditions. Scientists expected CO2 emissions to grow in 2017 (red dots), but they expected the growth in atmospheric concentrations (red bar) to be lower in 2017 compared to 2015 and 2016, in the absence of an El Niño event. Credit: Nature Climate Change.

Even though overall CO2 emissions have been relatively flat from 2014 to 2016, atmospheric concentrations saw a record increase in 2015 and 2016 (blue bars) due to El Niño conditions. Scientists expected CO2 emissions to grow in 2017 (red dots), but they expected the growth in atmospheric concentrations (red bar) to be lower in 2017 compared to 2015 and 2016, in the absence of an El Niño event. Credit: Nature Climate Change.

The landmark Paris Agreement from 2015, now literally signed by every nation in the world except the USA under Trump’s Administration, aims to limit warming to no more than 2 degrees Celsius past the average recorded at the start of the industrial revolution. However, the individual pledges that each nation has submitted are no way near ambitious enough.

Scientists working with the Global Carbon Project estimate that world emissions will rise by 2 percent to a record 37 billion metric tons in 2017. What’s more, deforestation and other changes in land use are expected to add another 4 billion metric tons of CO2, rounding off the total number of CO2 emissions for 2017 to 41 billion metric tons.

What’s mainly driving this upward trend in greenhouse gas emissions is China, which pledged under the Paris Agreement to peak emissions by around 2030 and to get 20 percent of its energy from non-fossil sources. China accounts for roughly a quarter of all man-made industrial emissions, so any upward or downward swing in the nation is sure to have a global influence. There were reasons to be optimistic as the government announced plans to cancel a hundred coal plants and is investing heavily in cleaner sources like solar, wind, and nuclear. The country also plans to sell millions of electric vehicles in the years ahead.

 CO2 emissions from fossil fuel use and industry since 1960 for China, the United States, the European Union, India, and the rest of the world (ROW). Credit: Environmental Research Letters.

CO2 emissions from fossil fuel use and industry since 1960 for China, the United States, the European Union, India, and the rest of the world (ROW). Credit: Environmental Research Letters.

Even though China’s economy has been growing, coal use began to taper off in the last three years. This year, however, emissions in China are expected to rise by 3.5 percent, driven by heavy infrastructure works aimed to boost the economy and unfavorable rain patterns that reduced hydropower output.

There is some good news, though. According to the same report released by the Global Carbon Project, 21 countries have managed to reduce their carbon emissions over the past decade, while simultaneously growing their economies. Among them are the United States, Britain, France, Germany, and Sweden.

It seems like the low-hanging fruit has been picked dry, though. In many developed countries, the rate of emission reductions has fallen considerably compared to the start of the decade. Industrial emissions in the United States are projected to fall by only 0.4 percent in 2017, compared to the 1.2 percent year-to-year average for the last decade. Oil use increased and a rise in natural gas prices slightly increased coal use. A similar situation is experienced by the European Union, whose emissions are expected to fall by just 0.2 percent this year, compared to the 2.2 percent average annual decline of the previous decade.

Surprisingly, India will only see 2 percent emissions growth for 2017, marking a huge improvement over the 6 percent year-to-year average rise in emissions it usually sees. It’s not clear how long this will last, as the country scrambles to offer electricity to its 300 million citizens still living in the dark.

The important announcement arrives while climate experts and world leaders gathered in Bonn, Germany, for the 23rd edition of the Conference of the Parties (COP). This is a tense conference, following President Trump’s announcement that he will see to it that the United States will withdraw from the Paris Agreement — which as of last year has entered into force. The rest of the world seems determined, however, to continue on its mission to decarbonize society in hope for a better, cleaner, safer future. The Paris Agreement is larger and far more important than the whims of any person.

Right now, many of the Paris pledges remain fairly opaque. It’s clear from today’s news that the world is not yet on track to reach its climate goals. More ambitious action is required so that, hopefully, we might see emissions peak in 2018, instead of rising again.

C02 flavor pic.

There hasn’t been this much CO2 in the air in 3 million years. We have to stop, UN warns

Atmospheric CO2 levels reached a record high in 2016– the highest the Earth has seen over in the last 3 million years. More worryingly, the World Meteorological Organization (WMO, part of the UN) reports that last year’s increase was 50% higher than the average over the last 10 years, and points to the appearance of a wildcard that could shatter the temperature goals set in Paris.

Researchers say that several factors, most notably human activity and the 2016 El Niño, powered the surge.

C02 flavor pic.

Image via Zappys Technology Solutions / Flickr.

Looking for a seriously spooky costume idea this Halloween? The WMO‘s latest Gas Bulletin might be just what you need. The document is produced each year by the WMO using data recorded by research stations in 51 countries. These measure concentrations of greenhouse gases such as carbon dioxide, methane, and nitrous oxide after the planet’s sinks (such as the biosphere or oceans) scrubbed all they could of these gasses from the atmosphere — so the WMO’s report doesn’t show the sum of gases pumped into the atmosphere, only what’s beyond the Earth’s ability to clean up.


It doesn’t look pretty. Overall, the document reports, in 2016, atmospheric concentrations of CO2 hit 403.3 parts per million (ppm), up from 400ppm in 2015.

“It is the largest increase we have ever seen in the 30 years we have had this network,” Dr Oksana Tarasova, chief of WMO’s global atmosphere watch programme, told BBC news.

“The largest increase was in the previous El Niño, in 1997-1998, and it was 2.7ppm; and now it is 3.3ppm. It is also 50% higher than the average of the last 10 years.”

El Niño phenomena can impact carbon levels in the atmosphere by causing droughts over wide areas, stifling plant growth and thus limiting their ability to absorb CO2.

There is a piece of good news in the report: human emissions have slowed down in the last couple of years. However, Dr. Tarasova warns that it’s not simply new emissions but rather the total levels in the atmosphere that matter; CO2 can remain airborne and active as a greenhouse gas for centuries. Over the last 70 years, the report notes, carbon dioxide levels in the atmosphere have started increasing 100 times faster than at the end of the last ice age due to population growth, intensive agriculture, deforestation, and industrialization. Overall, CO2 concentrations have more than doubled since that baseline.

CO2 comparison.

Image credits: WMO.

We’re already seeing the effects of this build-up. Since 1990, scientists have recorded a 40% increase in total radiative forcing — the difference between how much energy the Earth receives and how much it vents out. The higher the total radiative forcing gets, the more energy stays on Earth in the form of heat. Greenhouse gasses drive radiative forcing up by preventing energy in the atmosphere from radiating to outer space.

It’s a huge rise in concentration in what, geologically speaking, is an extremely short span of time — “like an injection of a huge amount of heat,” according to Dr. Tarasova.

“The changes will not take 10,000 years, like they used to take before; they will happen fast. We don’t have the knowledge of the system in this state; that is a bit worrisome!”

The last time our planet harbored similar CO2 concentrations was in the mid-Pliocene, a geological epoch spanning from three to five million years ago. The climate was 2 to 3 °C (3.6 to 5.4 °F) warmer back then, and sea levels were 10 to 20 m (32.8 to 65.6 ft) higher than today, pushed up by meltwater from the Greenland and West Antarctic ice sheets.


One more worrying trend seen by the WMO is a currently-unexplained increase of atmospheric methane, also larger than the average over the past decade. Growth was strongest in the tropics and subtropics, and carbon isotope analysis has revealed the growth is not released by burning fossil fuels; it’s not clear where it is coming from. The worst-case scenario, researchers fear, is that we’re looking at the start of a feedback mechanism.

Gasses bulletin.

Image credits WMO.

Methane is a much more powerful greenhouse gas than CO2, but it’s also less chemically stable, so it breaks down faster. A climate-driven, methane-based feedback mechanism, however, has the potential to drive up temperatures astoundingly fast. Such an event starts with methane from decaying biomass being generated much faster and in larger quantities than usual since we’re making it warmer. That methane will, in turn, raise average temperatures, which starts the loop again and generates even more methane before it can fully break down in the atmosphere.

It’s a particularly troubling find since the Paris Agreement didn’t foresee such an increase in methane levels — in effect, it’s a wildcard that could throw a major wrench in our plans. Overall, the WMO says, their new report doesn’t bode well at all for the targets governments around the world set in Paris.

“The numbers don’t lie. We are still emitting far too much and this needs to be reversed,” said Erik Solheim, head of UN Environment.

“We have many of the solutions already to address this challenge. What we need now is global political will and a new sense of urgency.”

WMO released the report a week in advance of the UN climate talks, to be held in Bonn. The authors urge policymakers to step up countermeasures to reduce the risk of global warming exceeding the Paris climate target of between 1.5C and 2C. The talks will carry on despite the US’ intended withdrawal from the Paris Agreement.

The WMO predicted 2017 will again break records for concentrations of CO2 and methane, but with lower growth rates because since is no El Niño effect.

Do volcanoes really emit more CO2 than humans?

No matter how you look at it, even during massive eruptions, mankind still emits much more carbon dioxide than volcanoes. In total, volcanoes barely emit 1% of mankind’s emissions. By itself, the US emits ten times more CO2 than volcanoes do.

Atmospheric CO2 levels measured at Mauna Loa observatory in Hawaii (NOAA) and Stratospheric Aerosol Optical Thickness at 50nm (NASA GISS).

There’s a big disparity between what scientists know about climate change and how the media presents the situation. Perhaps not surprisingly in this situation, numerous nonscientific or outright false arguments have made their way into the discourse. Among them, there’s this idea that mankind’s emission just don’t matter — volcanoes output so much CO2, some people say, it massively overshadows everything we do. Let’s see what the data says.

Volcanic CO2

The United States Geological Survey (USGS), alongside several other similar organizations, monitors volcanic emissions. According to their data, volcanoes (both land and underwater volcanoes) emit 200 million tons of carbon dioxide (CO2) annually. Of course, it’s not exactly a linear figure and major eruptions can bring dramatic changes.

Volcano eruptions can change a lot of things, but they’re not responsible for climate change. Image credits: Christina Neal, AVO/USGS.

The eruption of Mount Pinatubo, for instance, brought vast changes to the atmosphere. It ejected roughly 10 billion tonnes of magma, bringing vast quantities of minerals, toxic metals, and of course, greenhouse gases. It spewed more aerosols than any eruption since Krakatoa in 1883. By the time it was all finished, 42 million tonnes of CO2 were ejected into this atmosphere. But even with this eruption, volcanic activity didn’t match human activity. Ironically, aerosols from Pinatubo’s eruption formed a layer which dropped global temperatures by about 0.5 °C (0.9 °F) in the years 1991–93.

The data from the British Geological Survey, the British equivalent of the USGS, is quite different. Their estimations claim that volcanoes emit 300 million tonnes CO2 on an average year. This is, as far as we could find, the higher estimation for volcanic CO2. However, that is also not even close to the anthropic contribution.

Mankind CO2

While estimates for volcanic CO2 vary mostly between 200 and 300 million tons, our own CO2 emissions range around 24 billion tons — and that figure speaks for itself. No matter how you look at it, 2.4 gigatons are much more than 0.3.

Mankind’s activity dwarfs the of volcanoes, and our emissions are constantly growing, year after year. As volcanologists emphasize, it doesn’t even make much sense to compare the two.

“In fact, present-day volcanoes emit relatively modest amounts of CO2, about as much annually as states like Florida, Michigan, and Ohio,” writes USGS scientist Terrence M. Gerlach. “Anthropogenic CO2 emissions—responsible for a projected 35 gigatons of CO2 in 2010 [a figure that has grown significantly since] — clearly dwarf all estimates of the annual present-day global volcanic CO2 emission rate. Indeed, volcanoes emit significantly less CO2 than land use changes (3.4 gigatons per year), light-duty vehicles (3.0 gigatons per year, mainly cars and pickup trucks), or cement production (1.4 gigatons per year).

In case you’re wondering, there’s really not a lot of uncertainty around this. If volcanoes would be the driving factor of the atmospheric CO2 rise, we would see a correlation between volcanic eruptions and this steep rise in CO2 — and we don’t. Furthermore, a global volcanic CO2 output exceeding 35 gigatons per year would mean that the annual mass of volcanic CO2 is more than 3 times greater than the mass of erupted magma (~10.8 gigatons per year), and that’s simply not believable. Lastly, even if these estimates are a bit off, and even if they are way off, there’s still no term of comparison between volcanic and human CO2 emissions.

The bottom line

CO2 is a greenhouse gas and it is the main culprit we blamed for climate change. Volcanoes emit a significant amount of carbon dioxide into the atmosphere, but nowhere near what humans emit. We know this with a great degree of certainty.

Frozen Earth.

Coal formation sucked so much CO2 out of the atmosphere that Earth nearly froze over 300 million years ago

A new paper showcases the massive effect CO2 levels in the atmosphere have on Earth’s climate, describing its link to the great cooling period in the Carboniferous and Permian ages.

Frozen Earth.

Image credits Kevin Gill / Flickr.

We call it a ‘greenhouse’ gas for a reason. Today, it’s most widely known for the part it plays in climate change — but 300 million years ago, CO2 was involved in one of the most severe cooling events in Earth’s history. Using a large ensemble of computer simulations, Georg Feulner from the Potsdam Institute for Climate Impact Research was able to model how coal formation in the late Paleozoic came inches away of locking Earth into a ‘snowball state’.

A leaky greenhouse

In the very distant geological past, Earth was a much warmer place. Overall, it had a more uniform, tropical, humid climate than exists today, and plant life was going rampant. Vegetation resembled what you’d expect to see in a jungle setting today, but even more bountiful. Trees especially (they were still recent-ish technology at the time) were turbocharged by warm temperatures and swampy environments, growing to huge sizes. They lacked tree-rings, suggesting they could sustain growth throughout the year. All off this eventually led to Pangea (the only continent at the time) becoming plastered with immense quantities of biomatter. Some 300 million years ago,

Swampy, plant-infested areas are prime breeding spots for coal. Since that was basically all of the dry land at the time, most of the quality coal we’ve ever mined formed in this period. So much so that geologists know one subdivision of this time as the Carboniferous, which translates to ‘the coal-bearer’.

One unexpected side-effect of all this coal being formed, however, was that CO2 in the atmosphere was increasingly sequestered underground. Because of this, the Earth began to rapidly cool down. By the end of the Carboniferous, a full-fledged Ice Age had developed, one which came very close to lock our planet in a permanently frozen state.

“This illustrates the enormous dimension of the coal issue,” Feulner says. “The amount of CO2 stored in Earth’s coal reserves was once big enough to push our climate out of balance. When released by burning the coal, the CO2 is again destabilizing the Earth system.”

His research shows that some of the changes in temperature at the time can be attributed to other planetary factors, such as the axis tilt and the planet’s orbit. However, it also shows that CO2 concentrations in the atmosphere played the prime role in shaping the climate during the Carboniferous. Estimates drawn from samples of ancient soils and leaves show that CO2 levels fluctuated widely during this period, at one point dipping to about 100 parts per million (ppm) in the atmosphere — which is extremely low. Feulner’s models show that when atmospheric CO2 levels dip under 40 ppm, global glaciation is virtually guaranteed.

The flipside of Feulner’s findings is that burning coal today releases the CO2 captured over 300 million years ago. Today, we’re past the 400 ppm mark, which is above the 350 ppm deemed safe by the ICCP, but still under 450 ppm — a point where our chances of stabilizing the climate before planetary-scale irreversible damage is done are basically 50-50.

That’s because CO2 traps incoming heat in the Earth’s atmosphere, warming up the planet. Higher concentrations mean a higher percentage of incoming energy is trapped.

“It is quite an irony that forming the coal that today is a major factor for dangerous global warming once almost lead to global glaciation,” Feulner adds. “We should definitely keep CO2 levels in the atmosphere below 450 parts per million to keep our climate stable, and ideally much lower than that. Raising the amount of greenhouse gases beyond that limit means pushing ourselves out of the safe operating space of Earth.”

“Earth’s past teaches us that periods of rapid warming were often associated with mass extinction events. This shows that a stable climate is something to appreciate and protect.”

The paper “Formation of most of our coal brought Earth close to global glaciation” has been published in the journal PNAS.



Trump Forest wants to compensate for the POTUS’ climate policy by planting 100 new billion trees

In an effort to offset the US’s move away from the Paris goals, a trio of veteran climate campaigners want everyone to join in on planting the Trump Forest. A global forest of over 100 billion new trees.


Image credits David Mark.

The plan took off because of the organizers’ frustration over the POTUS “ignorance” on climate science, they say. Seeing as the president’s views on issues such as climate change won’t improve, they set out to beef up our planet’s ability to soak up the damage. Under the project, christened Trump Forest, people can either plant locally or pay for trees to be planted in a number of poorer countries which are most at risk from shifting climate.

All in all, the organizers say they need to plant a forest “the size of Kentucky” to balance out the effect Trump’s policy will have on the planet.

Billions of trees

The New Zealand-based project took off in March this year and has gained backing from around 730 people all around the world. Some 15,000 trees were pledged in the first month alone, and it’s since gone just shy of 200,000. The backers paid for all these trees to be planted in forest restoration projects in Madagascar, Haiti, Ethiopia, and Nepal, or bought and planted a tree themselves and sent a copy of the receipt to the project.

The organizers say they hope to tap into the growing global sense of frustration over the administration’s climate policy, which has seen the US leave the Paris agreement and undo many Obama-era climate policies.

“We’ve met some of the people on the front lines of climate change in Bangladesh, Mongolia and in other countries, and we found it extremely upsetting that Mr Trump’s ignorance is so profound,” said Adrien Taylor, a co-founder of Trump Forest.

“So we started to do something about it. Only a small percentage of the world voted him in, but we all have to deal with the consequences of his climate ignorance.”

The goal of Trump Forest is to offset 650 megatonnes of CO2 equivalent by 2025, which is their estimate of the effect Trump’s presidency will have. All in all, that means they need to plant over 100 billion new trees. That’s a massive undertaking, but the organizers are confident it can be done. They’ve had “a bit of hate mail” from people who support Trump’s policies, but generally have seen a lot of public support for the initiative, despite concerns that the project’s name goes to stroke the president’s ego.

“We want to plant a global forest that will offset all of the emissions that the Trump administration puts in the atmosphere. It sounds a bit ridiculous but it is completely feasible,” said Dr Daniel Price, another co-founder.

“We kind of want him to love the forest; this is his forest after all. We would love it if he tweeted about it,” Taylor added. “All we’re trying to do is pick up the slack he has created and do the work for him. So if he wants to take ownership of this forest just like Trump vodka and Trump Tower, we would welcome that; the phone line is open. So, Mr President, if you are reading this…”

Of course, they’re still a ways away from achieving their goal, but grassroots movements like this can make a significant difference and they’re something everyone can get involved in, setting a positive example. Lord knows we need them such examples.

Trees by themselves probably won’t stop climate change for us, no matter how many we plant. But they’d certainly help. So if you want to be part of the global forest, visit Trump Forests‘ website and see how you can help.

Scientists call out Pruitt’s false view of climate change

A few days ago, the head of the Environmental Protection Agency (EPA), Scott Pruit, said in an interview that he doesn’t believe “the science is in” and CO2 doesn’t cause climate change. Now, thirty prominent researchers, including a Nobel laureate, sent an open letter to Pruitt, calling him out on his false statements.

Science vs Politicians

In one corner, we have one hundred and fifty years of research, thousands of the world’s most brilliant minds, Nobel Prize winners, and effects which can easily be seen worldwide. In the other corner, there’s Trump, the fossil fuel lobby, and their henchmen. Image shows Scott Pruitt. Credits: Gage Skidmore.

Even ignoring the absolute absurdity of the situation in which the head of the EPA is clearly anti-environment, his statements are blatantly false. The letter reads:

“As scientists who study the Earth’s climate system, we are deeply troubled by your recent statement that there is ‘tremendous disagreement’ about whether carbon dioxide from human activities is ‘a primary contributor to the global warming that we see.’ That statement is incorrect.”

That’s a burn right there. In the world of science, definite statements such as the one above are rarely used, but this is absolutely necessary in this case. Scott Pruitt, head of the EPA, is a lawyer and a Republican politician. His scientific qualifications are limited at best — which was evident from the get-go. But now, as fact-checking organization Snopes reports, he just went against a scientific consensus that has lasted for over a century. Yes, the realization that CO2 warms the atmosphere dates back to the late 1850s and the pioneering work of British professor John Tyndall.

The letter continues:

“In fact, we know with exceptionally high degree of confidence that most of the climate warming over at least the last six decades has been caused by rising levels of carbon dioxide and other greenhouse gases in the atmosphere due to the burning of fossil fuels and other human activities. Further, we know that if we continue to increase the atmospheric levels of greenhouse gases, the Earth will continue to heat up, with serious consequences for economies and ecosystems across the globe.”

Sticking your head in the ground won’t solve any problem, but I’m not sure solving problems is what Pruitt is after. At this point, it seems extremely clear that Pruitt (and the Trump administration as a whole) does not have an unbiased view of climate change. This is not about a political disagreement of sorts, it’s about a government refusing to accept simple scientific principles — something which can have dire consequences for everybody. With the US being the world’s second largest polluter, their lack of action will cost us all.

“Just as there is no escaping gravity when one steps off a cliff, there is no escaping the warming that follows when we add extra carbon dioxide and other greenhouse gases to the atmosphere,” the scientists wrote. The group included Nobel laureate chemist Mario Molina of the University of California, San Diego, and eight members of the National Academies of Science.

Michael Oppenheimer, an atmospheric scientist at Princeton University, who also signed the letter said that there are two possibilities: either Pruitt is ignorant, or he’s simply lying. If the first possibility is true, then Oppenheimer declared his availability to brief Pruitt on climate change, but if the latter is true… there’s not much that can be done.

“I have no idea how he made this error, whether it’s intentional spinning of the facts, or, as I prefer to think, he really doesn’t know,” Oppenheimer said. ” We and any number of climate scientists would be perfectly happy to brief him about what’s known and what isn’t known and what the uncertainties really are.”

The correlation between atmospheric CO2 and global average temperatures. Image credits: Wiki Commons / U.S. Department of Energy

“Alternative facts”

In a very short time, the Trump administration has made a name for itself in its refusal of reality and its acceptance of what they call “alternative facts.” The term was coined by U.S. Counselor to the President Kellyanne Conway. Conway’s used the phrase “alternative facts” to describe what are demonstrably falsehoods promoted by the White House — and nowhere is this more evident than in their climate policies.

Again, just stop for a moment and think that the leader of the EPA just went on national television and said that CO2 doesn’t cause climate change. That’s literally the opposite of what the EPA itself states on its website:

“It is extremely likely that human activities have been the dominant cause of that warming,” and then, “Carbon dioxide is the primary greenhouse gas that is contributing to recent climate change.”

This letter sent by some of the world’s most respected scientists, but it’s not like that was the only such response. Earlier, the American Meteorological Society (AMS) also forwarded a letter to Pruitt with an official response underlining the key role that CO2 has played in raising our climate’s temperatures. This has been affirmed by thousands of independent scientists and numerous scientific institutions around the world based on multiple lines and independent evidence. AMS executive director Keith Seitter further emphasized this consensus by saying: “We are not familiar with any scientific institution with relevant subject matter expertise that has reached a different conclusion.”

The American Geophysical Society gave a similar response, pointing to their position on climate change, which “leaves no doubt that increasing atmospheric concentrations of carbon dioxide resulting from human activity is the dominant source of climate change during the last several decades.”

NASA says the same thing, NOAA says the same thing, there’s thousands and thousands of studies that say the same thing — it’s laughable that this is still being discussed. Unfortunately, that’s what it has gotten to.

The forests won’t fix our CO2 problem — in fact, they’ll scrub less than we assumed

Carbon dioxide absorption by growing biosphere may have been overestimated up to now, a new study concludes. This is due to previous estimates not taking into account the limiting factor of essential nutrients on plant development.

Image via Pixabay.

One effect of rising concentrations of CO2 in our atmosphere is that plants have more of the gas — a prime source of carbon — to metabolize, improving growth rates. It also raises average temperatures in cold areas, promoting plant growth. Satellite imagery has shown that while growth has declined in some areas, our planet is getting greener overall.

Climate scientists have pointed out that this increased quantity of plants will be able to scrub even more CO2 out of the atmosphere, forming a natural carbon sink, and helping mitigate our emissions. But they have overestimated just how much the biosphere will grow, and thus how much more carbon it will soak. By testing the effect of higher CO2 levels on forests growing in tropical and subtropical soils, a team from the Western Sydney University in Australia has found that the biosphere will likely grow less than what previous estimates have projected.

Plenty of carbon, scarce phosphorus

The team, led by David Ellsworth of Western Sydney University in Australia, says that forests will absorb around a tenth less CO2 than previously expected, meaning CO2 levels will rise even faster than our current models predict. The main limiting factor opposing CO2’s fertilizing effect is the lack of phosphorous in tropical and subtropical regions, they explain.

To determine how much the biosphere will grow, the team artificially raised CO2 levels in six plots of a mature eucalyptus forest near Sydney, which were growing in characteristically phosphorus-poor soil. The plots were covered in a mix of individuals of diverse species and ages.

Previous similar work in temperate forests (whose soils are much richer in phosphorus) found that CO2 increase could boost growth by as much as 20%. Ellsworth’s team found no evidence of growth boost in their plots at all. They attribute this difference to the limiting effect of phosphorous (a key nutrient) on growth. The results are backed by previous results, showing plant growth in the past 30 years didn’t see as much an increase as we estimated.

Another (very) limiting factor is human activity. Although some forests will grow faster if left to their own devices, we have a pretty consistent habit of cutting them down. Martin Brandt et al. show that while there’s overall more woody vegetation in Africa, the effects of warmer climate and rising levels of CO2 are offset by deforestation for raw materials and arable land in highly populated, humid areas, leading to a decrease in woody vegetation for these regions. The biggest increase in forests was seen in dry areas with low human populations, but it’s unclear if this makes up for the losses in vegetation elsewhere.

Ellsworth also points out that an increase in plant growth doesn’t necessarily translate to an increase in CO2 absorption and storage by plants.

Where does this leave us? Well, while it would be a nice turn of events it seems unlikely that the trees will clean our mess. So overall the situation takes a turn for the worse. Our best bet, as up to now, is to limit emissions and find ways to sequester CO2. In the meantime, we should also try as much as possible to mitigate the damage.

The full paper “Elevated CO2 does not increase eucalypt forest productivity on a low-phosphorus soil” has been published in the journal Nature Climate Change.


Scientists are trapping more and more CO2 into volcanic basalt

As we previously reported, researchers have been testing a method of underground CO2 storage: injecting it into basaltic rock. Now, building on that work, undiluted CO2 was stored and in a much higher quantity: 1,000 tonnes of fluid carbon dioxide were safely stored in underground basalts in Washington.

That’s trapped CO2. Image credits: PNNL.

Even in the most optimistic scenarios, we can’t completely eliminate all our greenhouse gas emissions. So if we want to become carbon-neutral or as close to it as possible, we’re going to need some ways of developing more “negative emissions”. Negative emissions are, as the name puts it, a way of retracting emissions from the atmosphere. Forests and kelp beds are often regarded as ways to reduce emissions, but they are only carbon sinks – they take existing carbon from the atmosphere and move it in the biosphere, a process which can be reversed by cutting trees or wildfires for example. Not to say that reforestation isn’t going to play a key role – because it is – but it’s technically not a negative emission.

Instead, researchers were thinking about something else: injecting carbon dioxide into the underground. Carbon Capture and Storage (CCS) is a field of science where CO2 is extracted from the atmosphere and stored underground. Geologists have mostly focused on existing voids, such as former oil fields, but that’s tricky because the fields are susceptible to leakage. So instead, they’re now turning to mineralizations – turning CO2 into minerals. Until now, this process was thought of as unpractical because it takes too long to solidify the CO2, but researchers from Columbia University, University of Iceland, University of Toulouse and Reykjavik Energy have found a way to make it work in recent years.

But while they first dissolved CO2 in water and injected it into a basalt formation, this new effort stored undiluted CO2. A team from the US Department of Energy’s Pacific Northwest National Laboratory (PNNL) had already shown that the chemical reactions could happen in lab conditions so they set out to test it in the field.

“Now we know that this mineral trapping process can occur very quickly, it makes it safe to store CO2 in these formations,” says researcher Pete McGrail. “We have been conducting laboratory tests on basalts from the region for several years that have conclusively demonstrated the unique geochemical nature of basalts to quickly react with CO2 and form carbonate minerals or solid rock, the safest and most permanent form for storage in the subsurface,” he added. “We know now that in a short period of time the CO2 will be permanently trapped.”

While previous efforts took place in Iceland, this time, they injected the fluid carbon dioxide into hardened lava flows some 900 meters (2,952 feet) underground, near the town of Wallula in Washington State. At that depth, basalt formations are rich in calcium, iron, and magnesium. When the CO2 is injected, these elements become unstable and then dissolve, forming ankerite, a carbonate material similar in some regards to limestone.

Their experiment was a definite success, and the carbon was bound to the basalt, never to escape again.

“[The CO2] can’t leak, there’s no place for it to go, it’s back to solid rock,” explains McGrail. “There isn’t a more safer or permanent storage mechanism.”

However, scaling this technique still remains problematic. Carbon storage is also expensive, and it’s unclear at this point how attempts to scale it up will affect its overall costs. The good thing is that basalt formations are plentiful around the world, but it’s also not clear just how big the absorptive capacity of the basalt really is. Global carbon emissions from fossil fuel use alone were 9.795 gigatonnes in 2014 and we’ve yet to understand just how much of that the basalts can suck up. So let’s not get overly excited just yet. It’s a promising technique and one that can definitely make a difference for global emissions, but we’re still miles away from actually make it work on a large scale. Let’s all head to the ‘cautiously optimistic’ room for now.

The findings are published in Environmental Science & Technology Letters

The catalyst is made of copper nanoparticles embedded into tiny carbon spikes. Credit: Oak Ridge National Laboratory

Cheap catalyst reverses combustion and turns CO2 into ethanol fuel

co2 to ethanol

Credit: Pixabay

Scientists at the Department of Energy’s Oak Ridge National Laboratory found a low-cost solution to turning CO2, a byproduct of combustion, into ethanol. The one-step reaction operates at room temperature and is set off by a novel catalyst made from readily available materials. The ‘secret sauce’ was the nanofabrication of the catalyst.

From CO2 to alcohol

Adam Rondinone and colleagues were investigating a multi-step reaction process to turn CO2 into a fuel but they soon found out that their catalyst was doing the entire reaction on its own.

“We discovered somewhat by accident that this material worked,” Rondinone said.

The serendipitous catalyst was made of carbon, copper, and nitrogen. However, the novelty lies in the way these materials were used on the nano level. Specifically, copper nanoparticles were embedded in carbon spikes to create a texture that drives and facilitates the CO2 to ethanol reaction. In doing so, this method enabled the creation of a powerful catalyst without the need for rare metals like platinum which are typically used for such purposes and are prohibitively expensive.

“They are like 50-nanometer lightning rods that concentrate electrochemical reactivity at the tip of the spike,” Rondinone said.

The catalyst is made of copper nanoparticles embedded into tiny carbon spikes. Credit: Oak Ridge National Laboratory

The catalyst is made of copper nanoparticles embedded into tiny carbon spikes. Credit: Oak Ridge National Laboratory

In the presence of this catalyst and a voltage, the solution of carbon dioxide dissolved in water turned into ethanol with a yield of 63 percent, scientists reported in their paper. Remarkably, this whole process took place at room temperature.

“We’re taking carbon dioxide, a waste product of combustion, and we’re pushing that combustion reaction backwards with very high selectivity to a useful fuel,” Rondinone said. “Ethanol was a surprise — it’s extremely difficult to go straight from carbon dioxide to ethanol with a single catalyst.”

Given the low-cost nature of this solution, the researchers envision an industrial scaled-up version of their catalytic converter that might one day turn thousands of tons of CO2 captured from the atmosphere into ethanol. The process could also work well as a storage medium for renewable energy, where the excess energy that can’t be fed to the grid is used to drive the reaction instead.

Of course, pulling CO2 — a greenhouse gas that warms the planet — from the air to turn into ethanol so it can be burned again doesn’t sound like the best environmental solution. Nor does using clean renewable energy to make a combustible fuel with greenhouse gasses as a byproduct. However, the United States is already making ethanol from corn and other crops. In the short term, this catalytic conversion of CO2 ought to be beneficial by offsetting the amount of net CO2 that ends up in the atmosphere. In the long run, we’ll have no need for such solutions because society should be sufficiently technologically advanced to make liquid fuels, or any combustible material for that matter, obsolete. Until then, the global energy problem needs to be met with a mix of solutions. There is no such thing as a one size fits all approach in this case.


‘We won’t ever see a month below 400ppm,’ said NASA’s chief climate scientist

Though September is historically the ‘freshest’ month of the year after plants had a whole summer at their disposal in the Northern Hemisphere to grow and suck CO2 out of the atmosphere, scientists announced today that a dangerous threshold has been crossed. Virtually all weather stations around the world seem to have registered carbon dioxide levels above 400 parts per million (ppm). And it seems like we’ll be locked above 400 ppm permanently. There’s no way but up!

Anyone who has breathed air with less than 300 ppm CO2 is now over 100 years old!

The first weather station that registered 400ppm was the Mauna Loa Observatory in Hawaii back in 2013. It would soon be joined by other stations along the northern hemisphere — an inevitable event that was only a matter of “when” not “if”.

Inevitable, because we humans have irreparably altered CO2 concentrations in the atmosphere since we invented farming, but really went to work once the Industrial Revolution was cranked into gear in the mid-19th century. The graph below is most revealing, as it traces how CO2 concentrations follow a saw pattern due to yearly variability. This time, we seemed locked in 400ppm — a CO2 concentration that hasn’t been seen in millions of years, up from 280ppm before the mid-19th century.


“Brief excursions toward lower values are still possible, but it already seems safe to conclude that we won’t be seeing a monthly value below 400 ppm this year – or ever again for the indefinite future,” wrote Ralph Keeling, the scientist who runs the Scripps Institute for Oceanography’s carbon dioxide monitoring program, in a recent blog post.

In March of this year, CO2 levels topped 400 ppm worldwide for an entire month. Then, in May, Antarctica — the last place where 400 ppm hadn’t been recorded — joined the rest of the pack as well. The latest critical threshold announced by scientists is that we’ve crossed 400 ppm and we’ll never see anything lower, not during our lifetimes for sure.

That’s because even if by some stroke of miracle all man-made CO2 emissions would stop tomorrow, the greenhouse gases already spewed are still trapped in the atmosphere. Greenhouse gas molecules emitted today can stay in the upper atmosphere for centuries before they break down. “In my opinion, we won’t ever see a month below 400 ppm,” said Gavin Schmidt, NASA’s chief climate scientist for Climate Central.


Credit: Climate Central

Today’s news was expected for some time, as we reported earlier that this year’s unusually strong El Niño event ought to push CO2 levels.

This figure, 400ppm, doesn’t pose a scientific significance, but it’s a very disheartening symbolic milestone. That’s because the last time the planet had 400ppm was 3 million years ago. Prior to the industrial revolution, natural climate variations caused atmospheric CO2 to vary between about 200 ppm during ice ages and 300 ppm during the warmer periods between ice ages.

Antarctica Ice

Global warming causes plants and soils to ‘burp’ more CO2

Antarctica Ice

Credit: Pixabay

A study of ice cores samples drilled from Antarctica decades ago has confirmed a long-standing assumption: as the planet warms, the biosphere releases more CO2 in a positive feedback loop.

The findings are extremely consequential for a lot of reasons. First of all, carbon budgets — the amount of greenhouse emissions governments can emit before passing a one degree Celsius warming threshold, for instance — need to be revised. Secondly, it reinforces the idea that the biosphere is a complex web whose interactions are difficult to sum up. We’re often surprised and we often underestimate, which is all the more reason to start serious climate change mitigation now.

Sweating CO2

The landmark study was made by a group of international researchers, among them Australian climate scientist Dr David Etheridge who has already participated in several ice core drilling expeditions. These sort of field studies are no walk in the park as researchers often have to battle against freezing temperatures ranging anywhere from minus 5 C to minus 40, as well as sickening winds.

The Nature Geoscience paper, however, made more use of previous ice core samples drilled from the 1980s well into the late 2000s. It is by peering inside the trapped gas bubbles of the ancient ice that scientists learn about glacial-interglacial cycles, changing atmospheric carbon dioxide levels, and climate stability over the last 10,000 years. Of particular interested were those gas bubbles trapped in the ice during the Little Ice Age (LIA), a brief period of global cooling which lasted for 250 years since the early 1500s. Volcano activity and a slightly weaker sun triggered this event which saw the world cool by around half a degree Celsius.

What was striking about this lil’ ice age was that the amount of carbon dioxide in the atmosphere also dropped in tune with the temperature. This oddity has been often pinned on less intense farming activities around this time due to wars and pandemics, but many were left unconvinced.

Now, analysis of carbonyl sulfide compounds from the ice cores suggests a direct biological relationship between the biosphere’s own carbon emissions and atmospheric temperatures. This looks like a more reasonable explanation.

Carbonyl sulfide concentration is linked to changes in gross primary production, namely the amount of chemical energy as biomass that primary producers create in a given length of time. In other words, when this chemical in the atmosphere jumps, it signals that plants are storing more carbon.

By studying the fluctuations of carbonyl sulfide compounds, the researchers came to the conclusion that increased temperatures are causing plants and soil to release more CO2, which causes more warming. That’s why feedback loops can be extremely dangerous once outputs pass a critical threshold which breaks equilibrium. And yes, plants do release CO2 — all the time actually as a metabolic byproduct of respiration.

Plants respire all the time because their cells need energy to stay alive, but plants can only photosynthesise when they are in the light. That’s why during daytime, when there’s light to trigger photosynthesis, plants turn CO2 into molecular oxygen, among other things. During the night, however, plants do not have enough energy (sunlight) to fix carbon, but need to respire to stay alive hence they become CO2 emitters.

Of course, the vast majority of plants are net fixers of CO2 and producers of O2. What the Nature paper suggests is that this balance is shifting towards the CO2 producing side as the planet warms. In regard to soil, it’s well established that cooler soil fixes more carbon.

“More warming, leads to more CO2 from the terrestrial biosphere, which leads to more warming,” Etheridge told The Guardian.

“We show that a decrease in gross primary production and a larger decrease in ecosystem respiration is the most likely explanation for the decrease in atmospheric CO2 and increase in atmospheric carbonyl sulfide concentrations. Therefore, temperature change, not vegetation re-growth, was the main cause of the increased terrestrial carbon storage,” the papers authors wrote.

At the moment, global CO2 emissions are rising at an unprecedented rate. It’s very likely that neither of us will get to see CO2 global average readings below 400 parts per million during our lifetimes. Again, the urgency of tackling climate change hasn’t been more real than ever.