Venus really sucks. It’s as hot as an oven with a dense, poisonous atmosphere. But how did it get that way?
Venus sucks. Seriously, it’s the worst. The global temperature is as hot as an oven, the atmospheric pressure is 90 times Earth, and it rains sulfuric acid. Every part of the surface of Venus would kill you dead in moments.
Let’s push Venus into the Sun and be done with that terrible place. Its proximity is lowering our real estate values and who knows what sort of interstellar monstrosities are going to set up shop there, and be constantly knocking on our door to borrow the mower, or a cup or sugar, or sneak into our yard at night and eat all our dolphins.
You might argue that Venus is worth saving because it’s located within the Solar System’s habitable zone, that special place where water could exist in a liquid state on the surface. But we’re pretty sure it doesn’t have any liquid water. Venus may have been better in the past, clearly it started hanging out with wrong crowd, taking a bad turn down a dark road leading it to its current state of disrepair.
Could Venus have been better in the past? And how did it go so wrong? In many ways, Venus is a twin of the Earth. It’s almost the same size and mass as the Earth, and it’s made up of roughly the same elements. And if you stood on the surface of Venus, in the brief moments before you evacuated your bowels and died horribly, you’d notice the gravity feels pretty similar.
In the ancient past, the Sun was dimmer and cooler than it is now. Cool enough that Venus was much more similar to Earth with rivers, lakes and oceans. NASA’s Pioneer spacecraft probed beneath the planet’s thick clouds and revealed that there was once liquid water on the surface of Venus. And with liquid water, there could have been life on the surface and in those oceans.
Here’s where Venus went wrong. It’s about a third closer to the Sun than Earth, and gets roughly double the solar radiation. The Sun has been slowly heating up over the millions and billions of years. At some point, the planet reached a tipping point, where the water on the surface of Venus completely evaporated into the atmosphere.
False color radar topographical map of Venus provided by Magellan. Credit: Magellan Team/JPL/NASA
Water vapor is a powerful greenhouse gas, and this only increased the global temperature, creating a runaway greenhouse effect on Venus. The ultraviolet light from the Sun split apart the water vapor into oxygen and hydrogen. The hydrogen was light enough to escape the atmosphere of Venus into space, while the oxygen recombined with carbon to form the thick carbon dioxide atmosphere we see today. Without that hydrogen, Venus’ water is never coming back.
Are you worried about our changing climate doing that here? Don’t panic. The amount of carbon dioxide released into the atmosphere of Venus is incomprehensible. According to the IPCC, the folks studying global warming, human activities have no chance of unleashing runaway global warming. We’ll just have the regular old, really awful global warming. So, it’s okay to panic a bit, but do it in the productive way that results in your driving your car less.
The Sun is still slowly heating up. And in a billion years or so, temperatures here will get hot enough to boil the oceans away. And then, Earth and Venus will be twins again and then we can push them both into the Sun.
I know, I said the words “climate change”. Feel free to have an argument in the comments below, but play nice and bring science.
OCO-2 leads the international Afternoon Constellation, or A-Train, of Earth-observing satellites as shown in this artist's concept. Japan’s Global Change Observation Mission - Water (GCOM-W1) satellite and NASA’s Aqua, CALIPSO, CloudSat and Aura satellites follow. Credit: NASA
NASA’s first spacecraft dedicated to studying Earth’s atmospheric climate changing carbon dioxide (CO2) levels and its carbon cycle has reached its final observing orbit and taken its first science measurements as the leader of the world’s first constellation of Earth science satellites known as the International “A-Train.”
The ‘first light’ measurements were conducted on Aug. 6 as the observatory flew over central Papua New Guinea and confirmed the health of the science instrument. See graphic below.
NASA’s OCO-2 spacecraft collected “first light” data Aug. 6 over New Guinea. OCO-2’s spectrometers recorded the bar code-like spectra, or chemical signatures, of molecular oxygen or carbon dioxide in the atmosphere. The backdrop is a simulation of carbon dioxide created from GEOS-5 model data. Credit: NASA/JPL-Caltech/NASA GSFC
Before the measurements could begin, mission controllers had to cool the observatory’s three-spectrometer instrument to its operating temperatures.
“The spectrometer’s optical components must be cooled to near 21 degrees Fahrenheit (minus 6 degrees Celsius) to bring them into focus and limit the amount of heat they radiate. The instrument’s detectors must be even cooler, near minus 243 degrees Fahrenheit (minus 153 degrees Celsius), to maximize their sensitivity,” according to a NASA statement.
The team still has to complete a significant amount of calibration work before the observatory is declared fully operational.
OCO-2 was launched just over a month ago during a spectacular nighttime blastoff on July 2, 2014, from Vandenberg Air Force Base, California, atop a the venerable United Launch Alliance Delta II rocket.
OCO-2 arrived at its final 438-mile (705-kilometer) altitude, near-polar orbit on Aug. 3 at the head of the international A-Train following a series of propulsive burns during July. Engineers also performed a thorough checkout of all of OCO-2’s systems to ensure they were functioning properly.
“The initial data from OCO-2 appear exactly as expected — the spectral lines are well resolved, sharp and deep,” said OCO-2 chief architect and calibration lead Randy Pollock of JPL, in a statement.
“We still have a lot of work to do to go from having a working instrument to having a well-calibrated and scientifically useful instrument, but this was an important milestone on this journey.”
Artist’s rendering of NASA’s Orbiting Carbon Observatory (OCO)-2, one of five new NASA Earth science missions set to launch in 2014, and one of three managed by JPL. Credit: NASA-JPL/Caltech
OCO-2 now leads the A-Train constellation, comprising five other international Earth orbiting monitoring satellites that constitute the world’s first formation-flying “super observatory” that collects an unprecedented quantity of nearly simultaneous climate and weather measurements.
Scientists will use the huge quantities of data to record the health of Earth’s atmosphere and surface environment as never before possible.
OCO-2 is followed in orbit by the Japanese GCOM-W1 satellite, and then by NASA’s Aqua, CALIPSO, CloudSat and Aura spacecraft, respectively. All six satellites fly over the same point on Earth within 16 minutes of each other. OCO-2 currently crosses the equator at 1:36 p.m. local time.
OCO-2 poster. Credit: ULA/NASA
The 999 pound (454 kilogram) observatory is the size of a phone booth.
OCO-2 is equipped with a single science instrument consisting of three high-resolution, near-infrared spectrometers fed by a common telescope. It will collect global measurements of atmospheric CO2 to provide scientists with a better idea of how CO2 impacts climate change and is responsible for Earth’s warming.
During a minimum two-year mission the $467.7 million OCO-2 will take near global measurements to locate the sources and storage places, or ‘sinks’, for atmospheric carbon dioxide, which is a critical component of the planet’s carbon cycle.
OCO-2 was built by Orbital Sciences as a replacement for the original OCO which was destroyed during the failed launch of a Taurus XL rocket from Vandenberg back in February 2009 when the payload fairing failed to open properly and the spacecraft plunged into the ocean.
The OCO-2 mission will provide a global picture of the human and natural sources of carbon dioxide, as well as their “sinks,” the natural ocean and land processes by which carbon dioxide is pulled out of Earth’s atmosphere and stored, according to NASA.
Here’s a NASA description of how OCO-2 collects measurements.
As OCO-2 flies over Earth’s sunlit hemisphere, each spectrometer collects a “frame” three times each second, for a total of about 9,000 frames from each orbit. Each frame is divided into eight spectra, or chemical signatures, that record the amount of molecular oxygen or carbon dioxide over adjacent ground footprints. Each footprint is about 1.3 miles (2.25 kilometers) long and a few hundred yards (meters) wide. When displayed as an image, the eight spectra appear like bar codes — bright bands of light broken by sharp dark lines. The dark lines indicate absorption by molecular oxygen or carbon dioxide.
It will record around 100,000 precise individual CO2 measurements around the worlds entire sunlit hemisphere every day and help determine its source and fate in an effort to understand how human activities impact climate change and how we can mitigate its effects.
OCO-2 mission description. Credit: NASA
At the dawn of the Industrial Revolution, there were about 280 parts per million (ppm) of carbon dioxide in Earth’s atmosphere. As of today the CO2 level has risen to about 400 parts per million, which is the most in at least 800,000 years, says NASA.
OCO-2 is the second of NASA’s five new Earth science missions planned to launch in 2014 and is designed to operate for at least two years during its primary mission. It follows the successful blastoff of the joint NASA/JAXA Global Precipitation Measurement (GPM) Core Observatory satellite on Feb 27.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
The Orbiting Carbon Observatory-2, NASA’s first mission dedicated to studying carbon dioxide in Earth’s atmosphere, lifts off from Vandenberg Air Force Base, California, at 2:56 a.m. Pacific Time, July 2, 2014 on a Delta II rocket. The two-year mission will help scientists unravel key mysteries about carbon dioxide. Credit: NASA/Bill Ingalls
The Orbiting Carbon Observatory-2, NASA's first mission dedicated to studying carbon dioxide in Earth's atmosphere, lifts off from Vandenberg Air Force Base, California, at 2:56 a.m. Pacific Time, July 2, 2014 on a Delta II rocket. The two-year mission will help scientists unravel key mysteries about carbon dioxide. Credit: NASA/Bill Ingalls
The Orbiting Carbon Observatory-2, NASA’s first mission dedicated to studying carbon dioxide in Earth’s atmosphere, lifts off from Vandenberg Air Force Base, California, at 2:56 a.m. Pacific Time, July 2, 2014 on a Delta II rocket. The two-year mission will help scientists unravel key mysteries about carbon dioxide. Credit: NASA/Bill Ingalls
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Following a nearly three-year long hiatus, the workhorse Delta II rocket successfully launched NASA’s first spacecraft dedicated to watching Earth breathe by studying Earth’s atmospheric carbon dioxide (CO2) – the leading human-produced greenhouse gas and the principal human-produced driver of climate change.
The Orbiting Carbon Observatory-2 (OCO-2) raced to orbit earlier this morning, during a spectacular nighttime blastoff at 2:56 a.m. PDT (5:56 a.m. EDT), Tuesday, July 2, 2014, from Vandenberg Air Force Base, California, atop a United Launch Alliance Delta II rocket.
The flawless launch marked the ‘return to flight’ of the venerable Delta II and was broadcast live on NASA TV.
Blastoff of NASA’s Orbiting Carbon Observatory-2 dedicated to studying carbon dioxide in Earth’s atmosphere, from Vandenberg Air Force Base, California, at 2:56 a.m. Pacific Time, July 2, 2014. Credit: Robert Fisher/America/Space
A camera mounted on the Delta II’s second stage captured a breathtaking live view of the OCO-2 spacecraft during separation from the upper stage, which propelled it into an initial 429-mile (690-kilometer) orbit.
The life giving solar arrays were unfurled soon thereafter and NASA reports that the observatory is in excellent health.
“Climate change is the challenge of our generation,” said NASA Administrator Charles Bolden in a statement.
“With OCO-2 and our existing fleet of satellites, NASA is uniquely qualified to take on the challenge of documenting and understanding these changes, predicting the ramifications, and sharing information about these changes for the benefit of society.”
NASA’s Orbiting Carbon Observatory-2, or OCO-2, inside the payload fairing in the mobile service tower at Space Launch Complex 2 on Vandenberg Air Force Base in California. The fairing will protect OCO-2 during launch aboard a United Launch Alliance Delta II rocket, which occurred at 5:56 a.m. EDT on July 2. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. Credit: NASA/30th Space Wing USAF
Over the next three weeks the OCO-2 probe will undergo a thorough checkout and calibration process. It will also be maneuvered into a 438-mile (705-kilometer) altitude, near-polar orbit where it will become the lead science probe at the head of the international Afternoon Constellation, or “A-Train,” of Earth-observing satellites.
“The A-Train, the first multi-satellite, formation flying “super observatory” to record the health of Earth’s atmosphere and surface environment, collects an unprecedented quantity of nearly simultaneous climate and weather measurements,” says NASA.
Science operations begin in about 45 days.
The 999 pound (454 kilogram) observatory is the size of a phone booth.
OCO-2 is equipped with a single science instrument consisting of three high-resolution, near-infrared spec¬trometers fed by a common telescope. It will collect global measurements of atmospheric CO2 to provide scientists with a better idea of how CO2 impacts climate change and is responsible for Earth’s warming.
OCO-2 poster. Credit: ULA/NASA
During a minimum two-year mission the $467.7 million OCO-2 will take near global measurements to locate the sources and storage places, or ‘sinks’, for atmospheric carbon dioxide, which is a critical component of the planet’s carbon cycle.
OCO-2 was built by Orbital Sciences as a replacement for the original OCO which was destroyed during the failed launch of a Taurus XL rocket from Vandenberg back in February 2009 when the payload fairing failed to open properly and the spacecraft plunged into the ocean.
The OCO-2 mission will provide a global picture of the human and natural sources of carbon dioxide, as well as their “sinks,” the natural ocean and land processes by which carbon dioxide is pulled out of Earth’s atmosphere and stored, according to NASA.
“This challenging mission is both timely and important,” said Michael Freilich, director of the Earth Science Division of NASA’s Science Mission Directorate in Washington.
“OCO-2 will produce exquisitely precise measurements of atmospheric carbon dioxide concentrations near Earth’s surface, laying the foundation for informed policy decisions on how to adapt to and reduce future climate change.”
It will record around 100,000 precise individual CO2 measurements around the worlds entire sunlit hemisphere every day and help determine its source and fate in an effort to understand how human activities impact climate change and how we can mitigate its effects.
At the dawn of the Industrial Revolution, there were about 280 parts per million (ppm) of carbon dioxide in Earth’s atmosphere. As of today the CO2 level has risen to about 400 parts per million.
“Scientists currently don’t know exactly where and how Earth’s oceans and plants have absorbed more than half the carbon dioxide that human activities have emitted into our atmosphere since the beginning of the industrial era,” said David Crisp, OCO-2 science team leader at NASA’s Jet Propulsion Laboratory in Pasadena, California, in a statement.
“Because of this, we cannot predict precisely how these processes will operate in the future as climate changes. For society to better manage carbon dioxide levels in our atmosphere, we need to be able to measure the natural source and sink processes.”
OCO-2 is the second of NASA’s five new Earth science missions planned to launch in 2014 and is designed to operate for at least two years during its primary mission. It follows the successful blastoff of the joint NASA/JAXA Global Precipitation Measurement (GPM) Core Observatory satellite on Feb 27.
Prelaunch view of NASA’s Orbiting Carbon Observatory-2 and United Launch Alliance Delta II rocket unveiled at Space Launch Complex 2 at Vandenberg Air Force Base in California. Credit: Robert Fisher/America/Space
The two stage Delta II 7320-10 launch vehicle is 8 ft in diameter and approximately 128 ft tall and was equipped with a trio of first stage strap on solid rocket motors. This marked the 152nd Delta II launch overall and the 51st for NASA since 1989.
The last time a Delta II rocket flew was nearly three years ago in October 2011 from Vandenberg for the Suomi National Polar-Orbiting Partnership (NPP) weather satellite.
The next Delta II launch later this year from Vandenberg involves NASA’s Soil Moisture Active Passive (SMAP) mission and counts as another of NASA’s five Earth science missions launching in 2014.
Stay tuned here for Ken’s continuing OCO-2, GPM, Curiosity, Opportunity, Orion, SpaceX, Boeing, Orbital Sciences, MAVEN, MOM, Mars and more Earth & Planetary science and human spaceflight news.
NASA’s Orbiting Carbon Observatory-2 (OCO-2) at the Launch Pad. This black-and-white infrared view shows the launch gantry, surrounding the United Launch Alliance Delta II rocket with the Orbiting Carbon Observatory-2 (OCO-2) satellite onboard. The photo was taken at Space Launch Complex 2, Friday, June 27, 2014, Vandenberg Air Force Base, Calif. OCO-2 is set for a July 1, 2014 launch. Credit: NASA/Bill Ingalls
NASA’s Orbiting Carbon Observatory-2 (OCO-2) at the Launch Pad
This black-and-white infrared view shows the launch gantry, surrounding the United Launch Alliance Delta II rocket with the Orbiting Carbon Observatory-2 (OCO-2) satellite onboard. The photo was taken at Space Launch Complex 2, Friday, June 27, 2014, Vandenberg Air Force Base, Calif. OCO-2 is set for a July 1, 2014 launch. Credit: NASA/Bill Ingalls[/caption]
After a lengthy hiatus, the workhorse Delta II rocket that first launched a quarter of a century ago and placed numerous renowned NASA science missions into Earth orbit and interplanetary space, as well as lofting dozens of commercial and DOD missions, is about to soar again this week on July 1 with NASA’s Orbiting Carbon Observatory-2 (OCO-2) sniffer to study atmospheric carbon dioxide (CO2).
OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas and the principal human-produced driver of climate change.
The 999 pound (454 kilogram) observatory is equipped with one science instrument consisting of three high-resolution, near-infrared spectrometers fed by a common telescope. It will collect global measurements of atmospheric CO2 to provide scientists with a better idea of how CO2 impacts climate change. OCO-2’s Delta II Rocket, First Stage At Space Launch Complex 2 on Vandenberg Air Force Base in California, the mobile service tower rolls away from the launch stand supporting the first stage of the Delta II rocket for NASA’s Orbiting Carbon Observatory-2 mission. Three solid rocket motors (white) have been attached to the first stage. The photo was taken during operations to mate the rocket’s first and second stages. Credit: NASA/Randy Beaudoin
The $467.7 million OCO-2 mission is set to blastoff atop the United Launch Alliance (ULA) Delta II rocket on Tuesday, July 1 from Space Launch Complex 2 at Vandenberg Air Force Base in California.
Liftoff is slated for 5:56 a.m. EDT (2:56 a.m. PDT) at the opening of a short 30-second launch window.
The California weather prognosis is currently outstanding at 100 percent ‘GO’ for favorable weather conditions at launch time.
OCO-2 poster. Credit: ULA/NASA
The two stage Delta II 7320-10 launch vehicle is 8 ft in diameter and approximately 128 ft tall. It is equipped with a trio of strap on solid rocket motors. This marks the 152nd Delta II launch overall and the 51st for NASA since 1989.
The last time a Delta II rocket flew was nearly three years ago in October 2011 from Vandenberg for the Suomi National Polar-Orbiting Partnership (NPP) weather satellite.
The Delta II will boost OCO-2 into a 438-mile (705-kilometer) altitude, near-polar orbit. Spacecraft separation from the rocket occurs 56 minutes 15 seconds after launch.
It will lead a constellation of five other international Earth monitoring satellites that circle Earth.
NASA’s Orbiting Carbon Observatory-2, or OCO-2, inside the payload fairing in the mobile service tower at Space Launch Complex 2 on Vandenberg Air Force Base in California. The fairing will protect OCO-2 during launch aboard a United Launch Alliance Delta II rocket, scheduled for 5:56 a.m. EDT on July 1. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. Credit: NASA/30th Space Wing USAF
The phone-booth sized OCO-2 was built by Orbital Sciences and is a replacement for the original OCO which was destroyed during the failed launch of a Taurus XL rocket from Vandenberg back in February 2009 when the payload fairing failed to open properly.
OCO-2 is the second of NASA’s five new Earth science missions launching in 2014 and is designed to operate for at least two years during its primary mission. It follows the successful blastoff of the joint NASA/JAXA Global Precipitation Measurement (GPM) Core Observatory satellite on Feb 27.
Orbiting Carbon Observatory-2 (OCO-2) mission will provide a global picture of the human and natural sources of carbon dioxide, as well as their “sinks,” the natural ocean and land processes by which carbon dioxide is pulled out of Earth’s atmosphere and stored, according to NASA..
“Carbon dioxide in the atmosphere plays a critical role in our planet’s energy balance and is a key factor in understanding how our climate is changing,” said Michael Freilich, director of NASA’s Earth Science Division in Washington.
“With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future.”
Artist’s rendering of NASA’s Orbiting Carbon Observatory (OCO)-2, one of five new NASA Earth science missions set to launch in 2014, and one of three managed by JPL. Credit: NASA-JPL/Caltech
It will record around 100,000 CO2 measurements around the world every day and help determine its source and fate in an effort to understand how human activities impact climate change and how we can mitigate its effects.
At the dawn of the Industrial Revolution, there were about 280 parts per million (ppm) of carbon dioxide in Earth’s atmosphere. As of today the CO2 level has risen to about 400 parts per million.
Stay tuned here for Ken’s continuing OCO-2, GPM, Curiosity, Opportunity, Orion, SpaceX, Boeing, Orbital Sciences, MAVEN, MOM, Mars and more Earth & Planetary science and human spaceflight news.
Blastoff of twin GRAIL A and B lunar gravity mapping spacecraft on a Delta II Heavy rocket on Sept. 10, 2011, from Pad 17B Cape Canaveral Air Force Station in Florida at 9:08 a.m. EDT. Credit: Ken Kremer/kenkremer.com
Artist's conception image of a young star surrounded by a disk (made up of rings) (Credits: NASA/JPL-Caltech)
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Catching a ring – or accretion disk – around a star isn’t unusual. However, catching a sharply defined carbon-dioxide ring around a young, magnetic star that’s precisely 1 AU away with a width 0.32 AU or less might raise a few eyebrows. This isn’t just any disk, either… It’s been likened as a “rope-like structure” and there’s even more to the mystery. It’s encircling a Herbig Ae star.
Discovered with the European Southern Observatory’s Very Large Telescope, the edges of this accretion disk are uniquely crisp. Located in the constellation of Centaurus at about 700 light years distant, V1052 (HD 101412) is a parent star with an infrared excess. “HD 101412 is most unusual in having resolved, magnetically split spectral lines which reveal a surface field modulus that varies between 2.5 to 3.5 kG.” says C.R. Cowley (et al). Previous studies “have surveyed molecular emission in a variety of young stellar objects. They found the emission to be much more subdued in Herbig Ae/Be stars than their cooler congeners, the T Tauri stars. This was true for HD 101412 as well, which was among the 25 Herbig Ae/Be stars they discussed. One exception, however, was the molecule CO2, which had a very large flux in HD 101412; indeed, only one T Tauri star had a higher CO2 flux.”
It’s not unusual for carbon dioxide to be found near young stars, but it is a bit more normal for it to be distributed throughout the disk region. “It’s exciting because this is the most constrained ring we’ve ever seen, and it requires an explanation,” explains Cowley, who is professor emeritus at the University of Michigan and leader of the international research effort. “At present time, we just don’t understand what makes it a rope rather than a dish.”
Because V1052 itself is different could be the reason. It is hypothesized the magnetic fields may be holding the rings in the disk structure at a certain distance. The idea has also been forwarded that there may be “shepherding planets”, much like Saturn’s ring structure, which may be the cause. “What makes this star so special is its very strong magnetic field and the fact that it rotates extremely slow compared to other stars of the same type,” said Swetlana Hubrig, of the Leibniz Institute for Astrophysics Potsdam (AIP), Germany.
One thing that is certain is how clean and well-defined the disk lines are centered around the Earth/Sun distance. This accords well with computer modeling where “A wider disk will not fit the observations.” These observations – and the exotic parent star – have been under intense scrutiny since 2008 and the findings have been recently published on-line in Astronomy and Astrophysics. It’s work that helps deepen the understanding of the interaction between central stars, their magnetic fields, and planet-forming disks. It also allows for fact finding when it comes to diverse systems and better knowledge of how solar systems form… even unusual ones.
“Why do turbulent motions not tear the ring apart?” Cowley wondered. “How permanent is the structure? What forces might act to preserve it for times comparable to the stellar formation time itself?”
When it comes to Herbig Ae stars, they are not only rare, but present a rare opportunity for study. In this case, it gives the team something to be quite excited about.
Pitted "swiss cheese" terrain at Mars' south pole hints at sublimation of underground CO2
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Scientists have spotted an underground reservoir near Mars’ south pole the size of Lake Superior… except that this lake is filled with frozen carbon dioxide – a.k.a. “dry ice”!
A recent report by scientists at the Southwest Research Institute in Boulder, CO reveals variations in Mars’ axial tilt can change how much carbon dioxide gets released into the atmosphere, affecting factors from the stability of water on its surface to the power and frequency of dust storms.
Thickness Map of Buried CO2 Ice Deposit
The Mars Reconnaissance Orbiter’s ground-penetrating Shallow Radar identified a subsurface deposit of frozen material, confirmed as carbon dioxide ice by its radar signature and visual correlation to the surface pitting seen above. As the polar surface warms during the Martian spring, underground CO2 deposits evaporate (or “sublime”) leaving behind round depressions in the frozen ground. (This has been aptly dubbed “swiss cheese terrain” by researchers on the HiRISE imaging team.)
While scientists were aware of seasonal CO2 ice layers atop the water ice this new discovery brings to light nearly 30 times more frozen CO2 than was previously believed to exist. In fact this particular deposit alone contains 80% the amount of CO2 currently present in the planet’s entire atmosphere.
The importance of this finding is how the carbon dioxide ultimately affects the global Martian climate as it freezes and thaws. When the CO2 is frozen and locked away in subsurface deposits like this, it’s not free to enter the atmosphere and do what CO2 does best: warm the planet… as well as increase atmospheric pressure. This means that liquid water cannot last as readily on the surface since it will either freeze or boil away. Also with less air pressure the strength of wind is decreased, so dust storms are less frequent and less severe.
When factored in with the axial tilt difference – and thus variations in the amount of sunlight hitting the poles – researchers’ models show that Mars’ average atmospheric pressure may at times be 75% higher than it is today.
These shifts in the orientation of the Red Planet’s axis occur on 100,000-year intervals… long by human standards but geologically very frequent. Mars may have had liquid water existing on its surface fairly recently!
Mars' south polar ice cap, seen in April 2000 by Mars Odyssey. NASA/JPL/MSSS
Although this may sound that Mars has had its own share of global warming due to CO2 emissions in its history, it must be remembered that Mars and Earth have very different atmospheric compositions. Earth’s atmosphere is much thicker and denser than Mars’, so even when doubling its CO2 content Mars’ atmosphere is still too thin and dry to create a strong greenhouse effect… especially considering that the polar caps on Mars increase cooling more than additional CO2 in the atmosphere raises global temperature. Without oceans and atmosphere to collect and distribute heat, the effect of any warming quickly radiates out into space…and eventually the planet swings back into a freeze-dried state.
“Unlike Earth, which has a thick, moist atmosphere that produces a strong greenhouse effect, Mars’ atmosphere is too thin and dry to produce as strong a greenhouse effect as Earth’s, even when you double its carbon-dioxide content.”
– Robert Haberle, planetary scientist at NASA’s Ames Research Center
High concentrations of carbon dioxide (in red) tend to congregate in the northern hemisphere during colder months, when plants can't absorb as much from the atmosphere. This picture is based on a NASA Goddard computer model from ground-based observations and depicts concentrations on March 30, 2006. Credit: NASA's Goddard Space Flight Center/B. Putman/YouTube (screenshot)
What if it were possible to just suck all the harmful pollutants out of the air so that they wouldn’t be such a nuisance? What if it were also possible to convert these atmospheric pollutants back into fossil fuels, or possibly ecologically-friendly bio fuels? Why, then we would be able to worry far less about smog, respiratory illnesses, and the effects that high concentrations of these gases have on the planet.
This is the basis of Carbon Capture, a relatively new concept where carbon dioxide is captured at point sources – such as factories, natural-gas plants, fuel plants, major cities, or any other place where large concentrations of CO² are known to be found. This CO² can then be stored for future use, converted into biofuels, or simply put back into the Earth so that it doesn’t enter the atmosphere.
Description:
Like many other recent developments, carbon capture is part of a new set of procedures that are collectively known as geoengineering. The purpose of these procedures are to alter the climate to counteract the effects of global warming, generally by targeting one of the chief greenhouse gases. The technology has existed for some time, but it has only been in recent years that it has been proposed as a means of combating climate change as well.
Schematic showing both terrestrial and geological sequestration of carbon dioxide emissions from a coal-fired plant. Credit: web.ornl.gov
Currently, carbon capture is most often employed in plants that rely on fossil fuel burning to generate electricity. This process is performed in one of three basic ways – post-combustion, pre-combustion and oxy-fuel combustion. Post-combustion involves removing CO2 after the fossil fuel is burned and is converted into a flue gas, which consists of CO2, water vapor, sulfur dioxides and nitrogen oxide.
When the gases travel through a smokestack or chimney, CO² is captured by a “filter” which actually consists of solvents that are used to absorb CO2 and water vapor. This technique is effective in that such filters can be retrofitted to older plants, avoiding the need for a costly power plant overhaul.
Benefits and Challenges:
The results of these processes have so far been encouraging – which boast the possibility of up to 90 % of CO² being removed from emissions (depending on the type of plant and the method used). However, there are concerns that some of these processes add to the overall cost and energy consumption of power plants.
According to 2005 report by the Intergovernmental Panel on Climate Change (IPCC), the additional costs range from 24 to 40% for coal power plants, 11 to 22% for natural gas plants, and 14 to 25% for coal-based gasification combined cycle systems. The additional power consumption also creates more in the way of emissions.
Vehicle emissions are one of the main sources of carbon dioxide today. Credit: ucsusa.org
In addition, while CC operations are capable of drastically reducing CO², they can add other pollutants to the air. The amounts of kind of pollutants depend on the technology, and range from ammonia and nitrogen oxides (NO and NO²) to sulfur oxides and disulfur oxides (SO, SO², SO³, S²O, S²O³. etc.). However, researchers are developing new techniques which they hope will reduce both costs and consumption and not generate additional pollutants.
Examples:
A good example of the Carbon Capture process is the Petro Nova project, a coal-fired power plant in Texas. This plant began being upgraded by the US Dept. of Energy (DOE) in 2014 to accommodate the largest post-combustion carbon-capture operation in the world.
Consisting of filters that would capture the emissions, and infrastructure that would place it back in the Earth, the DOE estimates that this operation will be capable of capturing 1.4 million tons of CO2 that previously would have been released into the air.
In the case of pre-combustion, CO² is trapped before the fossil fuel is even burned. Here, coal, oil or natural gas is heated in pure oxygen, resulting in a mix of carbon monoxide and hydrogen. This mix is then treated in a catalytic converter with steam, which then produces more hydrogen and carbon dioxide.
When complete, the US Department of Energy’s (DoE) Petro Nova will be the largest post-combustion carbon capture operation in the world. Credit: DOE
These gases are then fed into flasks where they are treated with amine (which binds with the CO² but not hydrogen); the mixture is then heated, causing the CO² to rise where it can be collected. In the final process (oxy-fuel combustion), fossil fuel is burned in oxygen, resulting in a gas mixture of steam and CO². The steam and carbon dioxide are separated by cooling and compressing the gas stream, and once separated, the CO² is removed.
Other efforts at carbon capture include building urban structures with special facilities to extract CO² from the air. Examples of this include the Torre de Especialidades in Mexico City – a hospital that is surrounded by a 2500 m² facade composed of Prosolve370e. Designed by Berlin-based firm Elegant Embellishments, this specially-shaped facade is able to channel air through its lattices and relies on chemical processes to filter out smog.
China’s Phoenix Towers – a planned-project for a series of towers in Wuhan, China (which will also be the world’s tallest) – is also expected to be equipped with a carbon capture operation. As part of the designers vision of creating a building that is both impressively tall and sustainable, these include special coatings on the outside of the structures that will draw CO² out of the local city air.
Then there’s the idea for “artificial trees“, which was put forward by Professor Klaus Lackner of the Department of Earth and Environmental Engineering at Columbia University. Consisting of plastic fronds that are coated with a resin that contains sodium carbonation – which when combined with carbon dioxide creates sodium bicarbonate (aka. baking soda) – these “trees” consume CO² in much the same way real trees do.
A cost-effective version of the same technology used to scrub CO² from air in submarines and space shuttles, the fronds are then cleaned using water which, when combined with the sodium bicarbonate, yields a solution that can easily be converted into biofuel.
In all cases, the process of Carbon Capture comes down to finding ways to remove harmful pollutants from the air to reduce humanity’s footprint. Storage and reuse also enter into the equation in the hopes of giving researchers more time to develop alternative energy sources.
CO2 is more than just the stuff that comes out of smokestacks, tailpipes, cigarettes and campfires. It is also a crucial element here on planet Earth, essential to life and its processes. It is used by plants to make sugars during photosynthesis. It is emitted by all animals, as well as some plants, fungi and microorganisms, during respiration. It is used by any organism that relies either directly or indirectly on plants for food; hence, it is a major component of the Carbon Cycle. It is also a major greenhouse gas, hence why it is so closely associated with Climate Change.
Joseph Black, a Scottish chemist and physician, was the first to identify carbon dioxide in the 1750s. He did so by heating calcium carbonate (limestone) with heat and acids, the result of which was the release of a gas that was denser than normal air and did not support flame or animal life. He also observed that it could be injected into calcium hydroxide (a liquid solution of lime) to produce Calcium Carbonate. Then, in 1772, another chemist named Joseph Priestley came up with of combining CO2 and water, thus inventing soda water. He was also intrinsic in coming up with the concept of the Carbon Cycle.
Since that time, our understanding of CO2 and its importance as both a greenhouse gas and an integral part of the Carbon Cycle has grown exponentially. For example, we’ve come to understand that atmospheric concentrations of CO2 fluctuate slightly with the change of the seasons, driven primarily by seasonal plant growth in the Northern Hemisphere. Concentrations of carbon dioxide fall during the northern spring and summer as plants consume the gas, and rise during the northern autumn and winter as plants go dormant, die and decay.
Traditionally, atmospheric CO2 levels were dependent on the respirations of animals, plants and microorganisms (as well as natural phenomena like volcanoes, geothermal processes, and forest fires). However, human activity has since come to be the major mitigating factor. The use of fossil fuels has been the major producer of CO2 since the Industrial Revolution. By relying increasingly on fossil fuels for transportation, heating, and manufacturing, we are threatening to offset the natural balance of CO2 in the atmosphere, water and soil, which in turn is having observable and escalating consequences for our environment. As is the process of deforestation which deprives the Earth of one it’s most important CO2 consumers and another important link in the Carbon Cycle.
As of April 2010, CO2 in the Earth’s atmosphere is at a concentration of 391 parts per million (ppm) by volume. For an illustrated breakdown of CO2 emissions per capita per country, click here.
We have written many articles about Carbon Dioxide for Universe Today. Here’s an article about the Carbon Cycle Diagram, and here’s an article about Greenhouse Effect.
