Climate explained: why Mars is cold despite an atmosphere of mostly carbon dioxide

If tiny concentrations of carbon dioxide can hold enough heat to create a global warming impact on Earth, why is Mars cold? Its atmosphere is 95% carbon dioxide.

When we look at Earth, the balance of these ingredients makes our planet habitable. Changes in this balance can result in effects that can be felt on a planetary scale. This is exactly what is happening with the increase of greenhouse gases in the  of our planet.

Increased concentrations of , methane, sulphur hexafluoride and other gases in the atmosphere have been raising the temperature of our planet’s surface gradually and will continue to do so for many years to come.

As a consequence, places covered in ice start melting and extreme weather events become more frequent. This poses a growing challenge for us to adapt to this new reality.

Small concentration, big effect

It is surprising to realise how little the concentration of carbon dioxide (CO₂) and other greenhouse gases has to change to cause such a shift in our climate. Since the 1950s, we have raised CO₂ levels in the atmosphere by a fraction of a percent, but this is already causing several changes in our climate.

This is because CO₂ represents a tiny part of Earth’s atmosphere. It is measured in parts per million (ppm) which means that for every carbon dioxide molecule there are a million others. Its concentration is just 0.041%, but even a small percentage change represents a big change in concentration.

We can tell what Earth’s atmosphere and climate were like in the distant past by analysing bubbles of ancient air trapped in ice. During Earth’s ice ages, the concentration of carbon dioxide was around 200ppm. During the warmer interglacial periods, it hovered around 280ppm, but since the 1950s, it has continued to rise relentlessly. By 2013, CO₂ levels surpassed 400ppm for the first time in recorded history.

This rise represents almost a doubling in concentration, and it clear that, in the recipe for Earth’s surface temperature, carbon dioxide and other greenhouse gases are to be used in moderation.

The role of water

Like flour for a cake, water is an important ingredient of the Earth’s surface. Water makes temperature move slowly. That’s why the temperatures in tropical rainforests does not change much, but the Sahara desert is cold at night. Earth is rich in water.

Let’s have a look at our solid . Mercury is the closest planet to the Sun, but it has a very thin atmosphere and is not the warmest planet. Venus is very, very hot. Its atmosphere is rich in carbon dioxide (over 96%) and it is very dense.

The atmosphere of Mars is also rich in   (above 96%), but it is extremely thin (1% of Earth’s atmosphere), very dry and located further away from the Sun. This combination makes the planet an incredibly cold place.

The absence of water makes the temperature on Mars change a lot. The Mars exploration rovers (Spirit at Gusev Crater and Opportunity at Meridiani Planun) experienced temperatures ranging from a few degrees Celsius above zero to minus 80℃ at night: every single Martian day, known as sol.

Terraforming or terra fixing

One of the interesting challenges we face while building space payloads, like we do at Griffith University, is to build instruments that can withstand such a wide  range.

I love conversations about terraforming. This is the idea that we could fly to a planet with an unbreathable atmosphere and fix it by using some sort of machine to filter nasty gases and release good ones we need to survive, at the correct amount. That is a recurrent theme in many science fiction films, including AliensTotal Recall and Red Planet.

I hope we can fix our own atmosphere on Earth and reduce our planet’s fever.

Greta Thunberg needs to cross the Atlantic again. Here are her options

Climate change activist Greta Thunberg
Chasing the COP25 climate summit.

Environmental activist Greta Thunberg is a long way from where she needs to be. Since a UN speech in New York in late September, the 16-year-old Swedish campaigner has spent weeks traveling overland en route to the COP25 climate summit in Santiago, Chile. But a last-minute change of location due to that city’s anti-government protests—the event will now be held in Madrid, Spain—has left her scrambling for an eco-friendly lift across the Atlantic.

Thunberg, who started the now-international student climate strikes in late 2018, appealed to her fans to help her get to Madrid by Dec. 2, promising gratitude to whoever could help her find transport.

Supporters will doubtless do what they can to help her to reach the summit in time. But what are the options currently on the table?

Mode of transport: Cargo ship
Carbon impact: Negligible

The most obvious and climate-friendly solution is riding aboard a cargo ship, thousands of which cross the Atlantic each year. It’s a highly unusual means of transport, though not unheard of: In June 2018, fellow Swede Kajsa Fernström Nåtby took the 12-day journey aboard the freight ship La Traviata, at a cost of $100 a day.

While cargo ships don’t generally transport passengers, as Wired reports, they occasionally have “a handful of cabins for transporting real passengers, tucked away among the sun-dried colors of hundreds of freight containers.” It’s a headache to get aboard (paperwork, doctor’s visits, a specialized agent), but one perhaps worth the carbon savings. Speaking to the magazine, low-carbon shipping expert Tristan Smith explained that these ships emit much less greenhouse gases per ton than planes—and the effect of an extra passenger is as minimal as “a feather in a giant’s cap.”

Mode of transport: Yacht
Carbon impact: It’s complicated

But while her own trip may not have had any significant climate impact, some of the crew members who traveled with her returned to Europe on flights. Others were also flown out for the yacht’s transatlantic voyage. While these flights were offset, it would arguably have been less impactful for Thunberg to offset her one flight, rather than necessitating half a dozen people to do the same.

Mode of transport: Cruise ship
Carbon impact: Circa three tonnes of CO2

A cruise ship is probably the worst possible way for Thunberg to reach Madrid. These hulking luxury liners emit between three and four times as much CO2 per kilometer as a flight—while being more expensive and much more time-consuming than flying.

Mode of transport: Flying
Carbon impact: 0.935 tonnes of CO2 (assuming an economy class seat with no offsets)

As a rule, Thunberg doesn’t fly. It’s not hard to see why: A single transatlantic flight can exceed some people’s entire carbon budget, and the message she is trying to spread might be muddied if she’s thought to be a hypocrite. But unless she can find a spot on a cargo ship, this may be the least climate-negative way to travel—especially if she purchases carbon offsets to “counterbalance” the effect of the flight.

The World Is Not Going To Halve Carbon Emissions By 2030, So Now What?

EDITOR’S PICK20,631 views

Last year, the Intergovernmental Panel on Climate Change (IPCC) reported that “limiting global warming to 1.5°C would require rapid, far-reaching and unprecedented changes in all aspects of society.” Specifically, “Global net human-caused emissions of carbon dioxide (CO2) would need to fall by about 45 percent from 2010 levels by 2030, reaching ‘net zero’ around 2050.” Since then, many advocates and policy makers have proposed that target as a political goal.

Here I’ll show you the simple mathematics of what achieving the 2030 target entails. The evidence shows clearly that the world is far from being on a path that will come anywhere close to that goal. That is not an opinion, it is just math.

Of course, climate change poses risks to our future, and aggressive mitigation and adaptation policies make good sense. So getting policy making right is important.

Let’s begin with a few key numbers as starting points. According to the 2019 BP Statistical Review of World Energy, in 2018 the world consumed in total almost 14,000 million tonnes of oil equivalent (mtoe). That energy supports the lives, hopes, aspirations of more than 7 billion people.

Like wealth, energy consumption is deeply unequal around the world, and many who do not have access to a full range of energy products and services are working hard to secure that access. So we should expect energy demand to continue to grow over the next decade. From 2000 to 2018, according to BP, consumption grew at about 2.2% per year, and ranged from a drop of 1.4% in 2009 to an increase of 4.9% in 2004. In the analysis below, I use an assumed 2.2% growth per year to 2030.

To simplify the analysis, I assume that emissions reduction targets will be met through reductions in fossil fuel consumption which occur across all fossil fuels. That allows us to equate a reduction in fossil fuel consumption with a reduction in carbon dioxide emissions. It also keeps us from misinterpreting a reduction in emissions from a switch from coal to natural gas. If the ultimate goal is net-zero carbon dioxide, then eventually all energy consumption will have to be carbon-free, meaning that carbon dioxide-emitted natural gas will have to also be eliminated.

I’ll also ignore the possibility of technologies of “negative emissions” which would allow the continued use of fossil fuels. The main reason for ignoring such technologies is that they don’t presently exist at scale, and don’t appear to be just over the horizon.

OK, with these starting points in place, let’s now look at the IPCC target for 2030. A 45% reduction in emissions from 2010, implies an allowance of about 5,950 mtoe of fossil fuel consumption for 2030, and a reduction of about 5,800 mtoe from 2018. If consumption grows by 2.2% per year to 2030, that means that the world will consume about 4,200 mtoe more in 2030 than in 2018.  So the grand total of new, carbon-free consumption by 2030 needed to hit the 45% reduction target is about 10,000 mtoe.

That means that the world will need add about 1,000 mtoe of carbon-free energy every year over the next decade. Over the past decade, the world added about 64 mtoe of carbon-free energy every year, and in 2018 it added a record 114 mtoe. So the world would need to accelerate the deployment of carbon-free energy by 9 times or more the rate observed in 2018, and about 15 times greater than that of the past decade.

The deployment of new carbon-emitting energy would obviously have to cease immediately. Over the past decade fossil fuel consumption has increased annually by an average of about 150 mtoe. Last year’s record increase of 114 mtoe of carbon-free energy was dwarfed by an increase in fossil fuels of more than 275 mtoe. It is accurate to say that the world’s growing supply of carbon-free energy is additive, and not replacing fossil fuels.

Discussions of climate policy often center on the deployment of carbon-free energy supply, but rarely discussed is the corresponding requirement for the decommissioning of fossil fuel energy. As I have argued in a previous column, the magnitude of the net-zero by 2050 challenge is equivalent to the deployment of a new nuclear plant every day for the next 30 years, while retiring an equivalent amount of fossil fuel energy every day. Emissions reductions for 2030 consistent with the IPCC view of the 1.5°C temperature target require a much great rate of deployment than one nuclear power plant worth of carbon-free energy deployment every day, because about half of the required emissions reductions are squeezed into the next 10 years.

The bottom line of this analysis should be undeniable: There is simply no evidence that the world is, or is on the brink of, making “rapid, far-reaching and unprecedented changes in all aspects of society” that would be required for the deep decarbonization associated with a 1.5°C temperature target. Anyone advocating a 50% reduction in emissions by 2030 is engaging in a form of climate theater, full of drama but not much suspense. But don’t just take it from me, do the math yourself.

Despite the overwhelming evidence on the unlikelihood of meeting the 2030 target, such realism has yet to take hold in climate policy discussions. Some even go so far as to claim that presentation of this type of analysis amounts to climate denial. For those making such claims, I’ve got news for you – the world is going to miss the 2030 target whether we talk about that reality or deny it, so we had better get to work on rethinking climate policy.

The Earth is warming. Here are the top warning signs, according to experts

PHOTO: A layer of smog covers Downtown and the nearby areas in Los Angeles, August 14, 2019.Etienne Laurent/EPA-EFE/REX via Shutterstock
WATCHHow you can impact climate change

The amount of greenhouse gases being emitted into Earth’s atmosphere has reached such a high level that it will take major changes around the world to mitigate the effects on climate change, experts say.

Interested in Climate Change?

Add Climate Change as an interest to stay up to date on the latest Climate Change news, video, and analysis from ABC News.

Add Interest

Greenhouse gasses such as carbon dioxide, which trap the sun’s heat, are the “most significant driver of observed climate change since the mid-20th century,” according to the U.S. Environmental Protection Agency.

To illustrate the pace of change, the National Oceanographic and Atmospheric Administration’s greenhouse gas index, which measures the impact of the gasses on climate, indicates it took approximately 240 years to go from 0 to 1, based on a 1990 benchmark. In the less than three decades since, the index says it has risen another 43% above the baseline.

“Climate change is now affecting every country on every continent. It is disrupting national economies and affecting lives, costing people, communities and countries dearly today and even more tomorrow,” the UN says on its sustainable development site. “Weather patterns are changing, sea levels are rising, weather events are becoming more extreme and greenhouse gas emissions are now at their highest levels in history.”

Here are the top issues contributing to climate change, according to the experts:

Contributing factors

Extraction of fossil fuels

The extraction of fossil fuels is one of the top issues affecting climate change, said Elizabeth Yeampierre, executive director of UPROSE, a New York-based organization that promotes sustainability, and co-chair of the Climate Justice Alliance, a network supporting the climate justice movement.

“We’re literally going deeper and taking out fossil fuel when the science is telling us that we have to stop,” Yeampierre said.

Fossils fuels can’t continue to be burned at the current rate “if we want to have a stable climate,” said Lindsey Allen, executive director of the nonprofit Rainforest Action Network.

“We immediately need to stop expanding our extraction of coal, and oil and gas,” she said.

Burning fossil fuels emits large amounts of carbon dioxide and extraction generates methane, both of which are more abundant in the earth’s atmosphere than they have been in 800,000 years, according to the EPA.

Nitrous oxide, the third principal greenhouse gas, which is also produced by burning fuels, has increased 20 percent since the start off the Industrial Revolution with the fastest rise in 22,000 years over the last century, the EPA said.

PHOTO: In this August 26, 2019, file photo, coal is loaded onto a truck at a mine on near Cumberland, Kentucky.Scott Olson/Getty Images, FILE
In this August 26, 2019, file photo, coal is loaded onto a truck at a mine on near Cumberland, Kentucky.


The transportation sector generated the largest share of greenhouse gas emissions in the U.S. at 29% in 2017, according to the EPA.

The emissions primarily come from the burning of fossil fuels in cars, trucks, ships, trains and planes, and more than 90% of the fuel used for transportation is petroleum-based, according to the EPA.

Transportation accounts for nearly 20% of emissions worldwide, said Jason Smerdon, climate scientist at Columbia University’s Lamont Doherty Earth Observatory.

Electrification of transportation, which would include electric cars, is one of the solutions to transforming the transformation sector, Smerdon said, as well as the development of hydrogen fuel cells and improvement of battery storage.

“We’re in reach of what needs to be done to make all that happen,” he said.

PHOTO: A layer of smog covers Downtown and the nearby areas in Los Angeles, August 14, 2019.Etienne Laurent/EPA-EFE/REX via Shutterstock
A layer of smog covers Downtown and the nearby areas in Los Angeles, August 14, 2019.

Electricity production

Electricity accounted for more than 27% of greenhouse gas emissions from the U.S. in 2017, and emissions from homes and businesses — primarily from fossil fuels burned for heat — accounted for another 11.6%, according to the EPA.

Nearly 63% of electricity in the U.S. comes from burning fossil fuels, namely coal and natural gas, according to the EPA.

Globally, more than 40% of emissions come from electricity and heat production, Smerdon said.

The energy sector presents the easiest possibility to transition to renewable, non-carbon based energy sources, which are “the cheapest form of energy out there,” according to Smerdon.

While there is currently a “fairly rapid transition” to wind and solar energy, driven by economics, “the question is whether it’s happening fast enough to reduce our overall greenhouse gas emissions,” he said.

“We need to do a lot to accelerate that,” Smerdon said.

PHOTO: Central Maine Power Co. Cape Substation in South Portland, Maine, is shown in this July 2, 2018, file photo. Derek Davis/Portland Press Herald via Getty Images
Central Maine Power Co. Cape Substation in South Portland, Maine, is shown in this July 2, 2018, file photo.


All industrial sectors contribute to the emissions of greenhouse gases, Smerdon said. In the U.S., industry accounted for 22% of emissions in 2017, according to the EPA.

Direct emissions in this sector come from burning fuels or chemical reactions, the EPA said, and indirect emissions come from the power needed to run the plants and the fossil fuels burned for that.

The warning signs of climate change

The climate crisis is construed by some as a far-off event (or one that is not happening at all), but it’s crucial to understand that the negative impacts are already happening, according to experts.

The earth is warming

Temperatures on Earth are already happening, Smerdon said.

As the surface temperature rises, the amount of ice and snow is decreasing, and the number and intensity of heat waves are increasing, Smerdon said.

With the increase of storage of energy within the earth’s systems comes the increase in holding capacity of moisture in the atmosphere, he explained, which leads to bigger downpours, stronger hurricanes and unprecedented rain events.

“One-in-thousand-year events are happening every couple of years,” Smerdon said.

“Temperatures are rising, snow and rainfall patterns are shifting, and more extreme climate events – like heavy rainstorms and record high temperatures – are already happening,” the EPA says on its website. “Many of these observed changes are linked to the rising levels of carbon dioxide and other greenhouse gases in our atmosphere, caused by human activities.”

PHOTO: A fire burns a tract of Amazon jungle as it is cleared by loggers and farmers near Porto Velho, Brazil, August 27, 2019.Ricardo Moraes/Reuters, FILE
A fire burns a tract of Amazon jungle as it is cleared by loggers and farmers near Porto Velho, Brazil, August 27, 2019.

Rainforests are burning at unprecedented levels

Setting fire to rainforests has been a method farmers have been using to clear land in Brazil for decades, but now because of drought conditions that have been affecting Brazil, they are burning hotter, longer and faster, Allen said.

Then, not only is a major source of carbon absorption and fresh water reservoir destroyed, but so is the biological diversity that resides within it, she said.

1 million species are at risk of extinction

Up to one million animal and plant species are being threatened with extinction due to human activity, some within decades, according to a United Nations report on the state of biodiversity and ecosystems published in May.

More than 40% of amphibians, nearly 33% of coral reefs and about a third of marine mammals are threatened, according to the report. An estimated 10% of the insect population is being threatened.

Food supply could dwindle

As droughts and downpours continue to impact agricultural areas, it will severely impact food supply, Smerdon said. Prices may also eventually be impacted, the EPA said.

Consumers will also feel those effects on their pocket books as jobs are lost and supply chains are disrupted, Smerdon said.

Currently, more than a third of the world’s land surface and nearly 75% of freshwater resources are devoted to crop or livestock production, a UN report released Wednesday found.

Oceans are rising

The sea levels continue to rise as ice in the arctic continue to melt at a rapid pace, said Dr. Ayana Elizabeth Johnson, a marine biologist, environmental policy expert and founder of the Urban Ocean Lab, a think tank for urban coastal cities.

Oceans could rise by 1-2 feet by 2100, even if greenhouse gas emissions are sharply reduced, the UN report said.

Rising levels will then threaten coastal cities and islands with severe flooding. According to the EPA, the rate of flooding is increasing along areas of the East and Gulf Coasts.

Carbon dioxide levels have also risen in the oceans over the past couple of decades, according to the EPA, leading to an increase in acidity. Higher carbon dioxide levels have also led to a lower concentration of aragonite, which makes it more difficult for some marine animals to build their skeletons or shells, the EPA said.

PHOTO: People search for salvageable items as they make their way through an area destroyed by Hurricane Dorian at Marsh Harbour in Great Abaco Island, Bahamas on Thursday, Sept. 5, 2019.Al Diaz/Miami Herald via AP
People search for salvageable items as they make their way through an area destroyed by Hurricane Dorian at Marsh Harbour in Great Abaco Island, Bahamas on Thursday, Sept. 5, 2019.more +

Climate impacts are creating crises in the developing world

As the effects of climate change hits developing countries, it creates millions of climate refugees and exacerbates political instability, according to the experts.

The climate emergency is also a human rights issue, Allen said, and research shows a connection between higher climate temperatures to more conflict, Smerdon said.

This creates “complicated, cascading effects” of social structures and government structures, he said, and creates refugees as people leave their homes for safer climates, Johnson said.

“It is wrong to create hundreds of millions of climate refugees and then close our borders when they seek shelter on our shores,” Johnson said.

Here’s Why Plants Aren’t Just Growing Faster With All The CO2 in The Atmosphere

main article image
(Kasturi Laxmi Mohit/Unsplash)
19 OCT 2019

Rising atmospheric carbon dioxide (CO2) is warming our climate, but it also affects plants directly.

A tree planted in the 1850s will have seen its diet (in terms of atmospheric carbon dioxide) double from its early days to the middle of our century. More CO2 generally leads to higher rates of photosynthesis and less water consumption in plants. So, at first sight, it seems that CO2 can only be beneficial for our plants.

At night, plants release CO2 just like animals or humans, and if those respiration rates increase simultaneously, the turnover of carbon increases, but the carbon stock doesn’t. You can think of this like a bank account – if you earn more but also spend more, you’re not becoming any richer.

Even if plants grow more and faster, some studies show there is a risk for them to have shorter lifespans. This again can have negative effects on the carbon locked away in biomass and soils.

In fact, fast-growing trees (e.g. plantation forests) store a lot less carbon per surface area than old, undisturbed forests that show very little growth.

Another example shows that plants in the deep shade may profit from higher levels of CO2, leading to more vigorous growth of vines, faster turnover, and, again, less carbon stored per surface area.

Water savings

The effect of CO2 on the amount of water plants use may be more important than the primary effect on photosynthesis. Plants tend to close their leaf pores slightly under elevated levels of CO2, leading to water savings. In certain (dry) areas, this may indeed lead to more plant growth.

But again, things are much more complex and we don’t always see positive responses.

Research we published in Nature Plants this year on grasslands around the globe showed that while dry sites can profit from more CO₂, there are complex interactions with rainfall.

Depending on when the rain falls, some sites show zero or even negative effects in terms of biomass production.

Currently, a net amount of three gigatons of carbon are thought to be removed from the atmosphere by plants every year. This stands against over 11 gigatons of human-induced release of CO2.

It is also unclear what fraction of the three gigatons plants are taking up due to rising levels of CO2.

In summary, rising CO2 is certainly not bad for plants, and if we restored forested land at a global scale, we could help capture additional atmospheric carbon dioxide.

But such simulations are optimistic and rely on conversion of much needed agricultural land to forests. Reductions in our emissions are unavoidable, and we have very strong evidence that plants alone will not be able to solve our CO2 problem.

Frozen Earth in ‘Snowpiercer’ Is a Grim (and Possible) Future for Our Warming Planet

Supertrain "Snowpiercer" barrels across a frozen Earth, in a new TNT series about the aftermath of a global climate catastrophe.

Supertrain “Snowpiercer” barrels across a frozen Earth, in a new TNT series about the aftermath of a global climate catastrophe.
(Image: © TNT)

NEW YORK — In the not-so-distant future, humanity’s last survivors ride a vast, never-stopping train across a frozen Earth. The fictional world of “Snowpiercer,” a new TV series airing on TNT in early 2020, is a grim one. A botched attempt to reverse runaway global warming has left Earth blanketed in ice and snow. Only a few thousand people — some wealthy and privileged and many desperate and wretched — survive, saved by a billionaire’s pet project: a beast of a supertrain (named Snowpiercer) that extends for miles, equipped to ride the rails until Earth is habitable again.

The series is based on the 1982 French graphic novel “Le Transperceneige,” as was the 2013 movie “Snowpiercer,” directed by Bong Joon-Ho.

At New York Comic Con on Oct. 5, the show’s cast and creators presented a glimpse of this broken Earth, the strange “ark” that barrels ceaselessly onward and the surviving humans who ride onboard. TNT’s version of the tale unfolds seven years after the global climate catastrophe and the train’s departure, when untold millions of people (not to mention all of Earth’s animals and plants) were left behind to die.

Related: Doom and Gloom: Top 10 Post-Apocalyptic Worlds

Bleak as this story is, it represents “a logical extension of what happens when you continue to ignore science and you’re forced to make a rash decision about how to save your planet,” said actor Daveed Diggs, who plays ex-homicide detective Andre Layton on the show.

That dire scenario is especially relevant today. Unprecedented and human-driven climate change is raising sea levelserasing glaciers and sea ice; and spawning dangerous wildfires, widespread droughts and intense heat waves. In fact, recent climate-related news fueled a sense of urgency for Graeme Manson, executive producer and showrunner of “Snowpiercer.”

“It lit a fire under me to want to tell this story now,” Manson told Live Science.

At New York Comic Con, the "Snowpiercer" cast fielded questions about how a climate catastrophe set the stage for the show's desperate, dystopian world. Left to right: Alison Wright, Daveed Diggs, Jennifer Connelly, Mickey Sumner, Lena Hall, Steven Ogg, Sheila Vand.

At New York Comic Con, the “Snowpiercer” cast fielded questions about how a climate catastrophe set the stage for the show’s desperate, dystopian world. Left to right: Alison Wright, Daveed Diggs, Jennifer Connelly, Mickey Sumner, Lena Hall, Steven Ogg, Sheila Vand.

(Image credit: Getty Images for WarnerMedia Company)

Global ice ages have frozen Earth in the past. But with accelerating climate change heating things up, is a planet-wide deep freeze even possible anymore? And could trying to artificially cool Earth save the planet, or would it trigger a cascade of consequences that produce a frozen wasteland like that in “Snowpiercer” — or something that’s even worse?

Between 750 million and 580 million years ago, three to four dramatic ice ages froze nearly all of Earth’s surface for about 10 million years at a stretch. During these periods of intense cold, average global temperatures plummeted to minus 58 degrees Fahrenheit (minus 50 degrees Celsius); these frigid conditions earned the planet the nickname “snowball Earth.”

Lesser ice ages emerge about once every 120,000 years, driven by shifts in Earth’s orbit and changes in our proximity to the sun, Robin Bell, a professor at Columbia University’s Lamont-Doherty Earth Observatory (LDEO) in New York City and president of the American Geophysical Union (AGU), told Live Science in an email.

“We should be having one [ice age] soon, except for our ongoing experiment in atmospheric chemistry,” said Bell, referring to fossil fuel burning that pumps quantities of greenhouse gases like carbon dioxide (CO2) into Earth’s atmosphere, accelerating warming. A future ice age could still happen, but only if atmospheric CO2 is drastically reduced, Maureen Raymo, a LDEO paleoclimatologist and research professor, told Live Science in an email.

Could artificially cooling the planet through geoengineering trigger an ice age or create a snowball Earth? “Physically, it’s not inconceivable,” said Gavin Schmidt, a climatologist and director of the NASA Goddard Institute for Space Studies in New York City.

During one of Earth's past deep freezes, the planet may have resembled Saturn's frozen moon Enceladus, pictured here.

During one of Earth’s past deep freezes, the planet may have resembled Saturn’s frozen moon Enceladus, pictured here.

(Image credit: NASA/JPL-Caltech/Space Science Institute)

Schmidt outlined one such geoengineering method. “If you put stuff into the atmosphere that’s white and reflective, that reduces the amount of solar radiation coming in and makes the planet colder,” he told Live Science. “It’s similar to what happens when big volcanoes erupt.”

For example, in 1991, the eruption of Mount Pinatubo in the Philippines spewed 20 million tons of sulfur dioxide into the stratosphere, causing global temperatures to drop by about 1 degree F (0.5 degrees C) from 1991 to 1993, according to the U.S. Geological Survey.

Related: 8 Ways Global Warming Is Already Changing the World

Removing excess CO2 from the atmosphere could also cool the planet; one way to do that could be to infuse the ocean with nutrients to encourage the growth of phytoplankton, microscopic marine algae that take up CO2 during photosynthesis.


“They would draw down CO2 from the atmosphere that would sink into the bottom of the ocean,” Schmidt said. “Then, everything would be back to normal.”

But take these procedures too far — block too much solar energy or siphon off too much atmospheric CO2 — and the result could be a global deep freeze, Schmidt said. Current atmospheric CO2 levels are about 410 parts per million, while preindustrial levels hovered at around 280 ppm, Schmidt said. Dip down to 180 ppm, and “then you’re in ice age territory,” he said.

What’s more, there are serious ethical concerns about launching such drastic actions to reset Earth’s climate.

“If we didn’t live here, it’d be much easier to play with the planet’s climate, but the consequences involve potentially billions of people,” Schmidt said. “We can’t even get a global agreement to reduce CO2. So the chances that we’d have a global agreement to put stuff in the atmosphere and change the climate seem very slim.”

Persistent hope

For Snowpiercer’s passengers, the chance to avert the worst impacts of climate change is long gone — “this is a story about what happens after it’s too late,” Diggs told Live Science. Yet, in spite of everything, the characters still find room for hope.

“Hope is inherent through living, continuing on,” actor Steven Ogg, who plays the rebellious gang leader, Pike, told Live Science. “If you’re waking up every day, that means, inherently, you’re living with hope.”

“You may think, ‘Well, I’ll die before I ever see the world go back to normal,'” said Lena Hall, whose character, Miss Audrey, manages the train’s brothel and cabaret. “But I don’t want to die now. I want to live and pass along what I know, and hope that the next generation, maybe they’ll see the change,” Hall said.

As dire as the real world’s climate crisis may seem, hope lingers here as well, in ongoing global actions to eliminate fossil fuel use and establish strategies for adapting to a warming world. But politicians and leaders need to act quickly, or a scenario as dire as that in “Snowpiercer” might be closer than we think, said actor Alison Wright; her character, Ruth Wardle, handles hospitality on the train.


“It’s not that much of a stretch, and it’s not a fantasy situation anymore,” Wright said. “Our story is just one possible result of what could happen.”

“Snowpiercer” will debut on TNT in the spring of 2020; check local listings.

Originally published on Live Science.

Australia’s vast carbon sink releasing millions of tonnes of CO2 back into atmosphere

Australia’s mangroves and seagrass meadows absorb 20m tonnes of CO2 a year but report warns damage to ecosystems contributing to climate change

Mangroves at high tide on the western side of Curtis Island on the Queensland coast=
 Mangroves at high tide on the western side of Curtis Island on the Queensland coast. Australia’s vast coastlines represent 5%-11% of all the so called ‘blue carbon’ locked up in mangroves, seagrasses and tidal marshes globally. Photograph: Matthew Abbott/The Guardian

Australia’s mangroves, tidal marshes and seagrass meadows are absorbing about 20m tonnes of carbon dioxide every year, according to a major new study that is the first to measure in detail the climate benefits of the coastal ecosystems.

But the study, published in the journal Nature Communications, warns that degradation of these “vegetated coastal ecosystems” was already seeing 3 million tonnes of CO2 per year being released back into the atmosphere.

The study reveals Australia’s vast coastlines represent between 5% and 11% of all the so called “blue carbon” locked up in mangroves, seagrasses and tidal marshes globally.

Some 44 scientists from 33 different research institutions collaborated on the study, which began in 2014.

Dr Oscar Serrano, at Edith Cowan University’s Centre for Marine Ecosystems Research, said it found the coastal ecosystems stored between 4,000m tonnes and 6,300m tonnes of CO2. Australia’s annual emissions hit a record high in 2018 of 558.4m tonnes of carbon dioxide equivalent.

“Globally, vegetated coastal ecosystems are being lost twice as fast as tropical rainforests despite covering a fraction of the area.”

Coastal ecosystems store carbon in their soils as well as in the plants themselves and, once absorbed, the carbon can be locked away for thousands of years if undisturbed. They are able to absorb at up to 40 times faster than forests.

“They also protect the coasts from erosion, are important nurseries for fisheries and they clear up the water so it’s very important for several reasons that we preserve these ecosystems,” Serrano said.

He said the ecosystems were being impacted by coastal developments, dredging and by climate change.

The annual losses of carbon from the coastal ecosystems was the equivalent of a 12% to 21% increase in Australia’s land-use emissions from activities such as land-clearing.

In 2015, mangroves on the Gulf of Carpentaria suffered an unprecedented mass dieback along a 1,000-kilometre stretch of coastline that coincided with a major heatwave.

Prof Norman Duke, of James Cook University, who was not part of the study, said the advantage of quantifying the carbon stored in mangroves was that it created a “marketable commodity” that could be used as part of carbon trading schemes.

Duke, who is leading a project to assess the mass dieback event, said mangroves were a particularly powerful tool to cut emissions because they had about five times more capacity to store carbon than trees on the land.

He said: “Because we’re trying to reduce the release of carbon into the atmosphere, this gives us a very strong incentive [to protect them]. But that’s not the only benefits that mangroves deliver – they give habitats to fisheries and protect our coastlines.”

Recovery of mangroves in the gulf has been hampered by dead mangroves, broken up by subsequent storms, piling up on areas of new growth. A seperate study has found the Gulf of Carpentaria’s dead mangroves emit eight times the amount of powerful greenhouse gas methane than live mangroves.

Dr Andy Steven, coasts research director at CSIRO and a co-author of the research, said: “When we started this work in 2014, we had no real numbers. We didn’t know how significant it was, or even if they were worth thinking about. But we’ve shown demonstrably that these ecosystems are very significant.”

To calculate the carbon content of the ecosystems, the researchers combined satellite data on the extent of mangroves and tidal marshes with direct measurements of the carbon stored in soils and plants.

Serrano and Stevens said there was hope the methodology used to calculate the climate benefits of vegetated coastal ecosystems would be used as part of Australia’s official national greenhouse accounts in the future.

Serrano said the research could position Australia as a “world leader” in protecting blue carbon ecosystems, adding other countries could use their work to make their own national measurements.

‘This Is All Wrong,’ Greta Thunberg Tells World Leaders At U.N. Climate Session


Greta Thunberg has a message for world leaders at the United Nations this week: “We’ll be watching you.” Speaking at the Climate Action Summit in New York, Thunberg added, “This is all wrong. I shouldn’t be up here. I should be back in school, on the other side of the ocean.”

But instead, Thunberg, 16, is trying to convince politicians to take climate change seriously, and to do something to stop a global warming trend that will affect the world’s children more than it affects anyone who’s currently in power.

In an impassioned speech, Thunberg told those who hold office, “you all come to us young people for hope. How dare you? You have stolen my dreams and my childhood with your empty words, and yet I’m one of the lucky ones. People are suffering. People are dying. Entire ecosystems are collapsing.”

Saying that the world is now in the early stages of a mass extinction, Thunberg criticized those who still speak of the crisis in terms of money and economic growth.

“How dare you?” she asked again, growing increasingly emotional as the audience cheered at the 2019 Climate Action Summit.

Citing more than 30 years’ worth of scientific studies and warnings that greenhouse gases and other factors were establishing a dangerous new environmental trend, Thunberg criticized politicians for not developing solutions and strategies to confront that threat.

“We’ll be watching you,” Thunberg told world leaders Monday, speaking at the U.N. Climate Action Summit in New York City.

Johannes Eisele/AFP/Getty Images

“You say you hear us and that you understand the urgency. But no matter how sad and angry I am, I do not want to believe that. Because if you really understood the situation and still kept on failing to act, then you would be evil. And that I refuse to believe.”

Thunberg then drilled into one aspect of a current international plan, which includes the goal of cutting current emissions levels in half over the next 10 years.

But that plan, she said, only provides a 50% chance of keeping the warming trend below 1.5 degrees Celsius.

“Fifty percent may be acceptable to you,” Thunberg said, before listing the many assumptions that underlie the estimate and the challenges that could thwart success.

“They also rely on my generation sucking hundreds of billions of tons of your CO2 out of the air with technologies that barely exist. So, a 50% risk is simply not acceptable to us — we who have to live with the consequences.”

Thunberg’s speech at a U.N. climate conference last December continues to draw viewers, captured by her direct tone and the clarity of her analysis of a complicated issue. For Monday’s speech in New York, the Swedish activist shared the stage with U.N. Secretary-General António Guterres, who praised the youth movement for raising awareness for climate action.

In her remarks, Thunberg accused politicians of pretending that the world’s dire climate problems can be solved with technical solutions and “business as usual.”

To back up her point, she cited a report by the Intergovernmental Panel on Climate Change, which concluded that for the world to preserve its best chance of meeting the 1.5-degree goal, countries had a “total carbon budget” of 420 gigatons of CO2 at the start of 2018 — meaning that together, countries shouldn’t exceed that amount.

“Today, that figure is already down to less than 350 gigatons,” Thunberg said, adding that at current emission rates, the carbon budget laid out by the IPCC “will be entirely gone in less than eight and a half years.”

Thunberg added, “There will not be any solutions or plans presented in line with these figures here today, because these numbers are too uncomfortable and you are still not mature enough to tell it like it is.”

To those wielding power, the activist said, “You are failing us, but young people are starting to understand your betrayal. The eyes of all future generations are upon you. And if you choose to fail us, I say: We will never forgive you.”

“We will not let you get away with this,” she added. “Right here, right now is where we draw the line.”

Thunberg concluded her remarks by saying, “The world is waking up. And change is coming, whether you like it or not.”

In a sign of her growing prominence, Thunberg’s remarks at the climate summit immediately preceded speeches from leaders such as Pope Francis and New Zealand’s Jacinda Ardern.

President Trump made a surprise visit to the same auditorium where Thunberg spoke — but the U.S. president arrived shortly after she concluded her remarks, entering while India’s Prime Minister Narendra Modi spoke.

We Need Biodiversity-Based Agriculture to Solve the Climate Crisis

The Earth is living, and also creates life. Over 4 billion years the Earth has evolved a rich biodiversity — an abundance of different living organisms and ecosystems — that can meet all our needs and sustain life.

Through biodiversity and the living functions of the biosphere, the Earth regulates temperature and climate, and has created the conditions for our species to evolve. This is what NASA scientist James Lovelock found in working with Lynn Margulis, who was studying the processes by which living organisms produce and remove gases from the atmosphere. The Earth is a self-regulating living organism, and life on Earth creates conditions for life to be maintained and evolve.

The Gaia Hypothesis, born in the 1970s, was a scientific reawakening to the Living Earth. The Earth fossilized some living carbon, and transformed it into dead carbon, storing it underground. That is where we should have left it.

A few centuries of fossil fuel-based civilization have brought our very survival under threat by rupturing the Earth’s carbon cycle, disrupting key climate systems and self-regulatory capacity, and pushing diverse species to extinction at 1000 times the normal rate. The connection between biodiversity and climate change is intimate.

Extinction is a certainty if we continue a little longer on the fossil fuel path. A shift to a biodiversity-based civilization is now a survival imperative.

Take the example of food and agriculture systems. The Earth has roughly 300,000 edible plant species, but the contemporary global human community eats only 200 of them. And, according to the New Scientist, “half our plant-sourced protein and calories come from just three: maize, rice and wheat.” Meanwhile, only 10 percent of the soy that is grown is used as food for humans. The rest goes to produce biofuels and animal feed.

Our agriculture system is not primarily a food system, it is an industrial system, and it is not sustainable.

The Amazon rainforests are home to 10 percent of the Earth’s biodiversity. Now, the rich forests are being burned for the expansion of GMO soy crops.

The most recent Intergovernmental Panel on Climate Change (IPCC) report on land and climate highlights how the climate problem begins with what we do on land.

We have been repeatedly told that monocultures of crops with intensive chemical inputs of synthetic fertilizers, pesticides and herbicides are necessary for feeding the world.

While using 75 percent of the total land that is being used for agriculture, industrial agriculture based on fossil fuel-intensive, chemical-intensive monocultures produce only 30 percent of the food we eat, while small, biodiverse farms using 25 percent of the land provide 70 percent of the food. Industrial agriculture is responsible for 75 percent of the destruction of soil, water and biodiversity of the planet. At this rate, if the share of fossil fuel-based industrial agriculture and industrial food in our diet is increased to 40 percent, we will have a dead planet. There will be no life, no food, on a dead planet.

Besides the carbon dioxide directly emitted from fossil fuel agriculture, nitrous oxide is emitted from nitrogen fertilizers based on fossil fuels, and methane is emitted from factory farms and food waste.

The manufacture of synthetic fertilizer is highly energy-intensive. One kilogram of nitrogen fertilizer requires the energy equivalent of 2 liters of diesel. Energy used during fertilizer manufacture was equivalent to 191 billion liters of diesel in 2000 and is projected to rise to 277 billion in 2030. This is a major contributor to climate change, yet largely ignored. One kilogram of phosphate fertilizer requires half a liter of diesel.

Nitrous oxide is 300 times more disruptive for the climate than carbon dioxide. Nitrogen fertilizers are destabilizing the climate, creating dead zones in the oceans and desertifying the soils. In the planetary context, the erosion of biodiversity and the transgression of the nitrogen boundary are serious, though often-overlooked, crises.

Thus, regenerating the planet through biodiversity-based ecological processes has become a survival imperative for the human species and all beings. Central to the transition is a shift from fossil fuels and dead carbon, to living processes based on growing and recycling living carbon renewed and grown as biodiversity.

Organic farming — working with nature — takes excess carbon dioxide from the atmosphere, where it doesn’t belong, and puts it back in the soil where it belongs, through photosynthesis. It also increases the water-holding capacity of soil, contributing to resilience in times of more frequent droughts, floods and other climate extremes. Organic farming has the potential of sequestering 52 gigatons of carbon dioxide, equivalent to the amount needed to be removed from the atmosphere to keep atmospheric carbon below 350 parts per million, and the average temperature increase of 2 degrees centigrade. We can bridge the emissions gap through ecological biodiversity-intensive agriculture, working with nature.

And the more biodiversity and biomass we grow, the more the plants sequester atmospheric carbon and nitrogen, and reduce both emissions and the stocks of pollutants in the air. Carbon is returned to the soil through plants.

The more we grow biodiversity and biomass on forests and farms, the more organic matter is available to return to the soil, thus reversing the trends toward desertification, which is already a major reason for the displacement and uprooting of people and the creation of refugees in sub-Saharan Africa and the Middle East.

Biodiversity-based agriculture is not just a climate solution, it is also a solution to hunger. Approximately 1 billion people are permanently hungry. Biodiversity-intensive, fossil-fuel-free, chemical-free systems produce more nutrition per acre and can feed more people using less land.

To repair the broken carbon cycle, we need to turn to seeds, to the soil and to the sun to increase the living carbon in the plants and in the soil. We need to remember that living carbon gives life, and dead fossil carbon is disrupting living processes. With our care and consciousness we can increase living carbon on the planet, and increase the well-being of all. On the other hand, the more we exploit and use dead carbon, and the more pollution we create, the less we have for the future. Dead carbon must be left underground. This is an ethical obligation and ecological imperative.

This is why the term “decarbonization,” which fails to make a distinction between living and dead carbon, is scientifically and ecologically inappropriate. If we decarbonized the economy, we would have no plants, which are living carbon. We would have no life on earth, which creates and is sustained by living carbon. A decarbonized planet would be a dead planet.

We need to recarbonize the world with biodiversity and living carbon. We need to leave dead carbon in the ground. We need to move from oil to soil. We need to urgently move from a fossil fuel-based system to a biodiversity-based ecological civilization. We can plant the seeds of hope, the seeds of the future.

This story is part of Covering Climate Now, a global collaboration of more than 220 news outlets to strengthen coverage of the climate story.

Climate Emergency Declarations Are the First Step. Here’s What Comes Next.

Last week, the climate emergency movement reached a historic milestone – 1,000 governments across the world have declared a climate emergency. Cities and jurisdictions representing over 210 million people from New York, Paris, London and Sydney to New Haven, Austin and Sacramento have joined a movement that has spread to all parts of society including colleges and universities and a variety of religious and cultural institutions.

Worldwide growth of the climate emergency movement has been rapid. In May 2019, the number of climate emergency declarations stood at just over 500 – just four months later those numbers have doubled.

For The Climate Mobilization, an advocacy organization that is pushing for the adoption of climate emergency declarations and the development of a WWII-scale mobilization in the United States to address this emergency, climate emergency declarations are the first step toward shifting society into emergency mode, where we take all necessary action to address the crisis situation we face.

Local governments can take immediate action to mobilize people and resources toward addressing the climate emergency in their backyards through a three-pronged approach that can be characterized as “Ban, Plan, and Expand.”


“Ban” means that after a climate emergency declaration is passed, local governments should pursue a rapid, just, managed phase-out of coal, oil and gas within the next decade. The science is clear: We must keep remaining fossil fuels in the ground. Local governments and jurisdictions must begin to use all possible legal avenues toward phasing out fossil fuels, from zoning restrictions to prevent the construction of oil infrastructure, to mandating the shift away from oil and gas heating systems in new building construction.

Local governments should also adopt strategies similar to those used against South African apartheid. These include withdrawal of municipal investments and contracts with companies or industries contributing to the destruction of the planet, and divestment as a tool to removing the social license of the fossil fuel industry through rejecting direct ownership and the commingling of public funds with investment in fossil fuel companies.


“Plan” refers to the deliberate democratization of local action on the climate emergency. This process involves elevating the voices of citizens, and particularly those from marginalized and frontline communities, in a just and equitable way to ensure mobilization efforts do not represent the current state of inequality existing in our nation and around the world. Local governments must shift their resources and priorities toward building the democratic mandate for emergency climate response. We must begin to explore new democratic tools such as mini-publics — including citizens’ juries, community assemblies and other more deliberative forms of public engagement — to elevate and explore the public’s views and create consensus on the complex policies that restoring a safe climate will require.

These mini-publics could inform local governments in the creation of a new Climate Mobilization Action Plan. This plan would guide for the rapid mobilization of resources necessary to transition to a climate-safe economy and local community. It would dismiss any ideas of incrementalism and move immediately toward the strongest mobilization-scale strategies, actions and legislation possible on issues of energy efficiency, renewable energy, zero emissions transportation, ecosystem conservation, food security, and adaptation and resilience within their jurisdictions.

Necessary to steer the plan forward is the creation of state or local Climate Emergency Mobilization Department (CEMD), functioning with public oversight and transparency. This new agency would possess real authority regarding coordination of climate emergency planning and implementation efforts within a said jurisdiction. We see this process happening already in several cities that have declared a climate emergency: Los Angeles recently created a Climate Emergency Mobilization Department and is hosting community assemblies on the climate emergency response, while Boulder, Colorado, is creating a Climate Mobilization Action Plan with heavy community involvement, and New Haven, Connecticut, is convening a new Climate Emergency Mobilization Task Force to lead the course to zero emissions by 2030.


“Expand” refers to how we must work to expand the climate emergency movement, moving beyond incremental policy shifts to implement rapid and comprehensive action necessary to restore a safe climate. From the expansion of public transportation, widespread ecological restoration, the rapid increase of local renewable energy generationmandating emissions cuts from buildings, local implementation is key to responding to the climate emergency. Local government needs leaders to publicly advocate for the adoption of state and national climate emergency commitments, programs and legislation. Governments declaring climate emergency have a responsibility to use their collective political power to strategically advocate for national and international World War II-scale climate mobilization.

The goal is to not only expand climate-safe policies and laws but to utilize thoughtful collaborative projects, networking, education and engagement with other governments around the world, academic institutions, nonprofit organizations and businesses to create a culture which makes these positive steps sustainable.

It’s a heavy lift, but doable.

Five years ago, a few friends on a shoestring budget started The Climate Mobilization with the goal of telling the truth about the climate emergency. Less than two years ago, the first climate emergency declaration in the United States was passed in Hoboken, New Jersey. And today, The Climate Mobilization’s model has been expanded internationally with groups like Extinction Rebellion through the United Kingdom, Canada and Australia and other places. Momentum to declare a national climate emergency by Congress is building, with over 60 cosponsors in the House of Representatives and seven in the Senate – including five of the seven U.S. senators running for the Democratic nomination for president — for a concurrent congressional resolution calling for a whole-economy mobilization response to the climate emergency.

We helped start the climate emergency movement to push government leadership to take global warming seriously. Our hope was by helping local communities on this issue, we could begin the process of generating national support for the WWII type of mobilization necessary to prevent apocalyptic climate disaster. As the movement has grown, we’ve realized that the strongest and most effective solutions to the climate emergency are often those driven by local communities.

Because not only is saving our planet doable – it’s something we must all do, together.

This story is part of Covering Climate Now, a global collaboration of more than 220 news outlets to strengthen coverage of the climate story.