Of note: “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.”
NASA Orbiter Reveals Big Changes in Mars’ Atmosphere
PASADENA, Calif. — NASA’s Mars Reconnaissance Orbiter has discovered the total amount of atmosphere on Mars changes dramatically as the tilt of the planet’s axis varies. This process can affect the stability of liquid water, if it exists on the Martian surface, and increase the frequency and severity of Martian dust storms.
Researchers using the orbiter’s ground-penetrating radar identified a large, buried deposit of frozen carbon dioxide, or dry ice, at the Red Planet’s south pole. The scientists suspect that much of this carbon dioxide enters the planet’s atmosphere and swells the atmosphere’s mass when Mars’ tilt increases. The findings are published in this week’s issue of the journal Science.
The newly found deposit has a volume similar to Lake Superior’s nearly 3,000 cubic miles (about 12,000 cubic kilometers). The deposit holds up to 80 percent as much carbon dioxide as today’s Martian atmosphere. Collapse pits caused by dry ice sublimation and other clues suggest the deposit is in a dissipating phase, adding gas to the atmosphere each year. Mars’ atmosphere is about 95 percent carbon dioxide, in contrast to Earth’s much thicker atmosphere, which is less than .04 percent carbon dioxide.
“We already knew there is a small perennial cap of carbon-dioxide ice on top of the water ice there, but this buried deposit has about 30 times more dry ice than previously estimated,” said Roger Phillips of Southwest Research Institute in Boulder, Colo. Phillips is deputy team leader for the Mars Reconnaissance Orbiter’s Shallow Radar instrument and lead author of the report.
“We identified the deposit as dry ice by determining the radar signature fit the radio-wave transmission characteristics of frozen carbon dioxide far better than the characteristics of frozen water,” said Roberto Seu of Sapienza University of Rome, team leader for the Shallow Radar and a co-author of the new report. Additional evidence came from correlating the deposit to visible sublimation features typical of dry ice.
“When you include this buried deposit, Martian carbon dioxide right now is roughly half frozen and half in the atmosphere, but at other times it can be nearly all frozen or nearly all in the atmosphere,” Phillips said.
An occasional increase in the atmosphere would strengthen winds, lofting more dust and leading to more frequent and more intense dust storms. Another result is an expanded area on the planet’s surface where liquid water could persist without boiling. Modeling based on known variation in the tilt of Mars’ axis suggests several-fold changes in the total mass of the planet’s atmosphere can happen on time frames of 100,000 years or less.
The changes in atmospheric density caused by the carbon-dioxide increase also would amplify some effects of the changes caused by the tilt. Researchers plugged the mass of the buried carbon-dioxide deposit into climate models for the period when Mars’ tilt and orbital properties maximize the amount of summer sunshine hitting the south pole. They found at such times, global, year-round average air pressure is approximately 75 percent greater than the current level.
“A tilted Mars with a thicker carbon-dioxide atmosphere causes a greenhouse effect that tries to warm the Martian surface, while thicker and longer-lived polar ice caps try to cool it,” said co-author Robert Haberle, a planetary scientist at NASA’s Ames Research Center in Moffett Field, Calif. “Our simulations show the polar caps cool more than the greenhouse warms. 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.”
The Shallow Radar, one of the Mars Reconnaissance Orbiter’s six instruments, was provided by the Italian Space Agency, and its operations are led by the Department of Information Engineering, Electronics and Telecommunications at Sapienza University of Rome. NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter project for NASA’s Science Mission Directorate at the agency’s headquarters in Washington. Lockheed Martin Space Systems in Denver built the spacecraft.
h/t to WUWT reader Dennis
source: http://www.nasa.gov/mission_pages/MRO/news/mro20110421.html
Since they are so very good at modeling Earth’c climate, what confidence do we have in this? I would take their consideration of CO2’s effects with lots of grains of NaCl. I would start with their definition of a greenhouse and then see if they are using the IPCC’s constants for CO2’s thermodynamics or the real values.
100,000 year cycle?
Oh, yes, an Ice Age cycle.
Not at all ‘unlike Earth’.
Hmmmm……..messages from the Red Planet.
If Percival Lowell were alive today, he’d be ROFL.
“A tilted Mars with a thicker carbon-dioxide atmosphere causes a greenhouse effect that tries to warm the Martian surface, while thicker and longer-lived polar ice caps try to cool it,” said co-author Robert Haberle, a planetary scientist at NASA’s Ames Research Center in Moffett Field, Calif.
=========
Anything else to report??
Your statement is old news, some say the science is well understood and a consensus has been reached.
Not even a flicker of something new, anything, I assume we are still exploring?
With the Mars Orbiter taking high quality pictures, we should be able to round up the SUVs causing this problem in short order.
OMG they model on Mars, too. Who-da thunk it.
“Another result is an expanded area on the planet’s surface where liquid water could persist without boiling. ”
Fascinating! How much does the axial tilt change and which way is the ’tilt’ progressing currently? To greater exposure of the south pole or lesser? When might the atmospheric pressure be sufficient to sustain water without ‘boiling’?
Since H2O is the only effective GHG, they’d do better to track water-ice transitions.
😉
Mars’s atmospheric pressure is ~1% of Earth and its CO2 content is ~96%. Earth’s atmosphere is ~0.04% CO2. Thus Mars has about 25 times as much CO2 in its atmosphere than Earth. That is, there are around 25 molecules intercepting IR for each molecule in Earth’s atmosphere. Assuming my arithmetic is correct.
So how does the “thinness” Mars’s atmosphere reduce the magnitude of the greenhouse effect when compared to Earth? I’m not saying it should necessarily be 25 times greater, just that seems it should be greater, rather than less.
The earth also has a very thin CO2 atmosphere. Almost none at all, measured in the parts per million.
The temperature of Venus, Earth and Mars shows much better correlation with the thickness of the atmosphere than with CO2 concentration.
Both Venus and Mars are mostly CO2 atmosphere, one is hot, the other cold. Earth with very little CO2 is in the middle. Where is the correlation?
Venus with a thick atmosphere is hot, Mars with a thin atmosphere is cold, and Earth with an atmosphere in the middle has a temperature in the middle. Much better correlation, even when adjusted for distance from the sun.
[[[Of note: “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.”]]]
These statements seem to be pulled out of thin dry air and fail to have any strong greening effect on me….
The location of these deposits near the south pole of Mars may tie in with the southern location of magnetic fields claimed to be as strong as on earth that would protect these deposits from solar wind erosion.
http://science.nasa.gov/science-news/science-at-nasa/2001/ast31jan_1/
ferd berple said @ April 21, 2011 at 10:27 pm
“Venus with a thick atmosphere is hot, Mars with a thin atmosphere is cold, and Earth with an atmosphere in the middle has a temperature in the middle. Much better correlation, even when adjusted for distance from the sun.”
Which is what I believe to be the case. But I am told by ever so many radiative physicists that the relative temperature of Earth’s atmosphere is not due to the lapse rate; it’s the CO2. And it still seems to me that 25 molecules of CO2 ought to be absorbing and reradiating 25 times as many photons as one molecule.
I seem to be missing something. Perhaps it’s because I’m cognitively dysfunctional 😉
That is the proof, that Aliens live on mars and produce CO2!
Gosh.
These “scientists” know as much about the effects of CO2 on climate on Mars as they do about the effects of CO2 on climate on Earth.
Y’know? I reckon that’s about right!
“even when you double its carbon-dioxide content.”
As Mars has an atmopshere comprised of 95% CO2, doubling it might be a problem?
How does an atmosphere of 95% carbon dioxide “double”?
Since the Greenhouse Effect violates the Laws of Thermodynamics let us look at the real reason for part of atmospheric heating, apart from solar. This is adiabatic which relies on atmospheric density. Since the atmosphere of Mars has a density far lower than Earth’s the adiabatic heating effect is far lower.
Planetary heating has nothing to do with the GHG effect of CO2. Jupiter has a warm atmosphere, similar to Earth at the 1000mbar level and there are no so called greenhouse gasses on Jupiter at all. That atmosphere is mainly hydrogen.
We are told Long Wave Radiation passes through most of the atmosphere only to be trapped by GHGs. Therefore we must conclude that non-GHGs are irrelevant to the so called greenhouse effect and that only GHGs matter.
If the above is true, then Mars, with so much more CO2 in it’s atmosphere must demonstrate a stronger greenhouse effect. Whether non-GHG gasses are present or not is irrlevant because they are “invisible” to radiation.
If Mars doesn’t demonstrate a strong greenhouse effect, the proponents of the greenhouse theort need to explain why not.
If someone is wiling to explain it, I’m willing to learn.
I seem to recall Mars South Pole was melting back in 2004. NASA had time lapsed picture of this event. Later NASA said that “dust storms” was causing the melting. I guess now it’s do to tilted Mars. Well it the time several other planets were experiencing warming including our planet. What I’m I to think? All the planets either tilted their axis or they all had massive dust storms at the same time. Of course the the Sun had nothing to do with it. Then again, it could be, driving SUVs over heated the whole system. Evil SUV drivers.
Mars does have dust devils, so one presumes that there is convectional activity going on, which means the atmosphere must have a troposphere that exists at the adiabatic lapse rate. So convection would represent a significant method of heat loss, as it does on earth. This means that temperature would be a function of the simple thickness of the atmosphere.
Why would the presence of moisture in the martian atmosphere matter? The atmosphere is already warmed to the adiabatic lapse rate, so adding more GHG is irrelevant surely.
Louis Hissink says:
April 22, 2011 at 1:59 am
and
H.R. says:
April 22, 2011 at 2:16 am
An atmosphere of 95% carbon dioxide “double” can be shown in the following example:
Assume the Martian atmosphere consists of 100 “parts”. There are 95 parts of CO2, and 5 parts “other”, where other is the sum total of nitrogen (2.7 parts), argon (1.6 parts), oxygen (0.13 parts), and traces of additional gases. Now, if we hold the “other” parts constant at 5, but double the CO2, the atmosphere consists of 190 parts CO2 and 5 parts “other”, for a total of 195 parts. We’ve doubled the CO2 parts (95 to 190), but the percentage of of CO2 has changed from 95% to 97.4% (190/195).
However, if your question is really about how to add CO2 to the Martian atmosphere, I’ll gladly volunteer to drive an ‘evil’ CO2-spewing SUV on Mars, if someone will cover the interplanetary travel expenses. 🙂
1) The “doubling of CO2 content” they refer to is the melting of the dry ice cap, which they estimate to contain almost as much CO2 as the atmosphere itself.
2) There is a word for the carbon hysteria that leads people to claim that CO2 drives temperature more strongly than distance from the sun or atmospheric mass, but it would be impolite to use it. Let’s just say it’s a byproduct of equestrian pursuits.
@Louis Hessink:
Nicely spotted, Louis! Heh heh – ‘“even when you double its carbon-dioxide content.”
Of course, the scientist who wrote that really meant “double its carbon-dioxide quantity”. But, heck, why would we expect a scientist to use scientifically correct language, eh? If they did that, we might also expect them to use the scientific method…
Pompous Git says: April 21, 2011 at 11:22 pm
And it still seems to me that 25 molecules of CO2 ought to be absorbing and reradiating 25 times as many photons as one molecule.
The amount of sunlight at mars’ orbit is much less than here, I believe it diminishes by the square of the distance from the source. So while there is much more relative CO2, there is much less light to play with, and no mass to hold the heat.
Mars had water not that long ago or the landscape would have been decimated by meteor strikes. Within the last 500 million years.
So, essentially, CO2 might be driven by that vast empty depressive nothingness called . . . space and everyt’ing in it? :p
Poor Martians. They have overstretched their economy to the point of no return while sequestering all that carbon industriously near the South Pole just to Save the Planet, so they’ve gone extinct and all this for naught. The careless warrior-god turns its Pole to the sun and re-releases the nasty stuff which was eagerly waiting in the pipeline. Isn’t it dismal a bit?
“Planetary heating has nothing to do with the GHG effect of CO2. Jupiter has a warm atmosphere, similar to Earth at the 1000mbar level and there are no so called greenhouse gasses on Jupiter at all. That atmosphere is mainly hydrogen.”
When corrected for the distance from the sun, venus has a temperature almost identical to earth at the 1000mbar level, and its atmosphere is CO2.
So here we have 3 atmospheres. One CO2, one N2/O2, and one H2. All showing similar temperatures at similar pressures. This is impossible if the Greenhouse Theory is correct.
This in itself should have falsified the GHG theory if science was not so politicized. However, scientists rely on funding, which means their ideas must coincide with those that grant the funding.
Findings that are likely to lead to funding cuts are not likely to be published. How many scientists have the courage to publish a finding that is going to put them out of work? How many publishers are going to publish a finding that is likely to hurt their readership numbers?
Consider the example of medicine. If has been widely published that ulcers are caused by infection. Prior to this discovery, medicine believed that ulcers were “man-made”. That the patient was responsible for creating their own problem through a combination of diet and stress. The solution prescribed was a combination of diet change and stress reduction.
The numbers are convincing. Treatment of ulcers with antibiotics has a high cure rate. Treatment with diet and stress reduction has a low cure rate. Yet many doctors persisted in their belief that the patient, not infection was the causes of ulcers, for many years afterwards.
We have similar situation with climate science. There is a tendency among experts, when they cannot find the cause of something, to blame the problem on someone else. They don’t stop to consider that the problem is their lack of knowledge. So, doctors didn’t stop to consider that just maybe the problem with ulcers was a lack of knowledge. Instead, when the cause could not be found, doctors blamed the disease on the patient.
In the case of Global Warming, experts are not able to explain the rise in temperature in the late 20th century. So, according to the IPCC, the reason must be man-made CO2. Exactly the same psychology as with ulcers. If we cannot find the cause, then blame the problem on other people. Do not stop to consider that the reason the experts cannot explain the warming is due to a lack of knowledge. That would force the experts to admit that they are not really as expert as they would like you to believe.
Well said Fred Berple.
I had noticed the venus issue a long time ago myself. At the same pressure, temperature is almost the same as here, even for a sulfuric acid/CO2 atmosphere! But this shouldn’t be surprising: PV=nRT. Since a planetary atmosphere is not in an enclosed space, V can be ignored, and instead substitute in gravity. Lapse rate is what’s important: the movement of heat from the surface up to where it can radiate away. GHG can affect the lapse rate, but when looking at other planets with very disparate atmospheres, it seems that effect is not all that great. The science really needs more investigation; other planetary bodies provide us the only place where the variables are different from here, for us to test hypotheses against. We really need to start looking into that more.
Mars: gravity 0.38 Earth, distance to Sun, 1.54 Earth, Atmopsheric pressure 7-9 mb vs 1000 sealevel Earth.
Mars receives 0.42X the sun power of earth, or 143.6 W/m2. The average temperature is -63C vs +14.5C for Earth. The escape velocity is 0.44 of Earths. That one area in the article has about “80% as much CO2 as in the current atmosphere, so if Mars could warm up it would have a surface pressure of (approx) 15 mb plus what other gases that would contribute as they boiled out of the ground. Could we guess at another 30, for an all-in of 45 mb? Assuming that NASA has Mars figured out.
Mars used to have a LOT of atmosphere. There used to be enough to have surface waters in large amounts, with rain and rivers. Details of the surface show sanddunes. Considering the thinness of the atmosphere, even a hurricane force (I’ve read) won’t do much but whisper on our skin (should we be able to expose our skin). I consider the energy required on Earth to create sanddunes and wonder how Mars could create them with such a thin atmosphere. Dust storms, yes, including the dust devils mentioned, but sand dunes? Not enough power.
Methinks the Red Planet has more atmosphere tied up somewhere than we understand. The escape velocity doesn’t seem low enough relative to the Earth and Venus to have lost through boiling off into space its oxygen content it must have had (for the red surface and the previous presence of water). Seems odd (note: astronomy buffs can correct me here re the escape velocity needed to lose one’s atmosphere.)
Is it possible that the insolation loss that created the ice ages cooled Mars enough that the atmosphere froze out and is still there but buried beneath a thin layer of dust (and in the caps)? Is the UV enough to disassociate all the water, such that the hydrogen disappears and the remaining oxygen oxidizes the surface? so that the atmosphere is still there, but now bound up and non-retrievable?
We think we know everything about how Earth and Mars and other things operate, yet I suspect our knowledge is very shallow indeed. We have climate change pinned but we don’t know why 1810 to 1855 was so cold. We say we know why 1940 – 1965 cooled (pollution) but that seems kinda self-serving for the Clean Air Act crowd. As if nobody else polluted the air before or after. Including China.
ferd berple says: April 22, 2011 at 8:11 am
“The temperature of Venus, Earth and Mars shows much better correlation with the thickness of the atmosphere than with CO2 concentration. ”
This is certainly true. In my understanding, the average distance from the sun (ie total power input) and the overall thickness of the atmosphere (ie lapse rate) are the two biggest factors in surface temperature. The amount of GHGs are simply a correction that slightly adjusts the affect of the first two. (If there were no GHGs AT ALL in an atmosphere, then I believe that would have a significant impact).
However, since the earth’s average distance from the sun and the earth’s average atmosphere are pretty constant, then the GHGs can become a significant factor for adjusting the temperature above or below the effect of the distance & thickness.
“So here we have 3 atmospheres. One CO2, one N2/O2, and one H2. All showing similar temperatures at similar pressures. ….This in itself should have falsified the GHG theory….”
First, I assume you mean Jupiter for the H2 atmosphere. At 1 bar, the temperature on Jupiter is 165 K (-108 C), so it is hardly “similar” . This in itself falsifies your falsification. 🙂
Also, Venus is significantly different from earth in that is it covered 100% by clouds. This means that no IR radiation from the surface escapes to space, while a significant amount of IR radiation from earth does. The top of the cloud layer on Venus would be expected to have a similar temperature to earth, not the surface of Venus.
These differences are enough that a simple “greenhouse theory” would not be expected to predict surface temperatures based merely (or even primarily) on GHG concentrations.
Doug Proctor says: April 22, 2011 at 9:51 am
“The escape velocity doesn’t seem low enough relative to the Earth and Venus to have lost through boiling off into space its oxygen content it must have had ”
Here is a handy image. http://abyss.uoregon.edu/~js/images/atmos_ret.gif Mars is warm enough to have lost its water to space, but not O2. However, oxygen would also have been absorbed to oxidize the surface. Indeed, the early earth is thought to have had much less oxygen (see http://en.wikipedia.org/wiki/Atmosphere_of_Earth#Evolution_of_Earth.27s_atmosphere for example). The O2 increased primarily due to the presence of plant life, which Mars does not currently have (and may well never have had).
Of course they have CO2 problems, the idiot Martians cut down all the trees!
ferd berple says:
April 21, 2011 at 10:27 pm
“The temperature of Venus, Earth and Mars shows much better correlation with the thickness of the atmosphere than with CO2 concentration.”
Yes, and with distance from the Sun taken into account this correlation ecomes causation.
John Marshall says:
April 22, 2011 at 2:21 am
“Since the Greenhouse Effect violates the Laws of Thermodynamics let us look at the real reason for part of atmospheric heating, apart from solar.”
Yes, indeed!
Baa Humbug says:
April 22, 2011 at 2:45 am
“If someone is wiling to explain it, I’m willing to learn.”
Same here.
Please see “Understanding the Thermodynamic Atmosphere Effect”, at http://www.oarval.org/ThermoAtmos.htm (Joseph E. Postma, March 2011)
Pompous Git says:
April 21, 2011 at 10:07 pm
“Mars’s atmospheric pressure is ~1% of Earth and its CO2 content is ~96%. Earth’s atmosphere is ~0.04% CO2. Thus Mars has about 25 times as much CO2 in its atmosphere than Earth. That is, there are around 25 molecules intercepting IR for each molecule in Earth’s atmosphere. Assuming my arithmetic is correct.
So how does the “thinness” Mars’s atmosphere reduce the magnitude of the greenhouse effect when compared to Earth? I’m not saying it should necessarily be 25 times greater, just that seems it should be greater, rather than less.”
For the same reason Venus, which has an atmosphere 92 times thicker than Earth, has surface temps of over 600 degrees, despite the fact that 99.9% of its sunlight is reflected away from it by sulfur dioxide clouds. Even though nitrogen and oxygen aren’t “warming” gasses, they still hold heat, and the 99x higher pressure of Earth vs Thicker atmospheres, tho, typically moderate the temp differential between dayside and nightside versus what you would see for a black body without any atmosphere.
While Mars has a lot more CO2 than Earth does, there isnt the O2 or N2 there to create pressure or hold heat, nor is there much of any atmospheric moisture, which also holds heat. There also aren’t any oceans to act as rather large heatsinks like they do on Earth, so the Martian surface radiates away its absorbed daytime heat rather quickly at night.
Pompous Git says:
April 21, 2011 at 11:22 pm
Which is what I believe to be the case. But I am told by ever so many radiative physicists that the relative temperature of Earth’s atmosphere is not due to the lapse rate; it’s the CO2. And it still seems to me that 25 molecules of CO2 ought to be absorbing and reradiating 25 times as many photons as one molecule.
——————————————————————————————-;
The lapse rate, namely 6.5C/km, is calculated from the Earth’s temperature.
First you use Stefan-Boltzman Law and the Sun to estimate the average temperature of the Earth, namely, -18C degreess. This is the radiative part.
Second, you find the height in the atmosphere where this temperature occurs – for the Earth it’s roughly 5 km – then use the equations of state (usually the atmosphere is assumed to be an ideal gas) and calculate average pressure exerted on the Earth by the atmosphere. From this pressure you can calculate the average temperature on the surface, namely, 33C. This is the thermodynamic part.
There is no need for the greenhouse conjecture unless you ignore the atmosphere gravity.
Venus reflects roughly 2/3 of the sunlight yet it’s extremely hot on the surface. It’s trivial to calculate the correct average surface temperature using gravity and the thermodynamics.
I remember a paper posted here a few months back where they falsified the GH theory, and everyone pooh-pooh it. I found one equation in that document that I thought was quite useful:
TSI = σ*Ts⁴*(Rs²/(Rs² + Rp²)),
where σ is the Stephan-Boltzmann constant, Ts is the surface temperature of the Sun, Rs is the radius of the Sun, and Rp is the planetary distance from the Sun.
I looked on the web for TSI values for Mercury, Venus, Earth, and Mars with their perihelion and aphelion distances in astronomical units. These are the values I found:
Mercury = 14446 – 6272 W/m² (0.3075 – 0.4667 AU)
Venus = 2647 – 2576 W/m² (0.7184 – 0.7282 AU)
Earth = 1413 – 1321 W/m² (0.9833 – 1.017 AU)
Mars = 715 – 492 W/m² (1.382 – 1.666 AU)
If I use 5.6704E-8 W/(m²*K⁴) for the Stephan-Boltzmann constant, 5778K for the surface temperature of the Sun, 695500 km for the Sun’s radius, and 149597870.7 km for an astronomical unit I get:
Mercury = 14443.68 – 6271.17 W/m²
Venus = 2646.772 – 2576.014 W/m²
Earth = 1412.816 – 1320.737 W/m²
Mars = 715.2309 – 492.1686 W/m²
It’s pretty good agreement for a simple formula from a paper everyone didn’t like.
Jim