Active volcanoes on Venus, heat gets out how?

Posted: June 20, 2015 by tchannon in volcanos

Michele dropped a link on Suggestions, here is the story

After the end of the ESA Venus mission rapidly changing hotspots are found in IR images, after earlier noticing large changes in Sulpur levels.Why now?

I’m not keen on ESA PR, doesn’t even link the GRL paper so I’ll add a good blog link afterwards.

Image

Title Brightness changes in Ganiki Chasma
Released 18/06/2015 2:00 pm
Copyright From E. Shalygin et al (2015)

18 June 2015

ESA’s Venus Express has found the best evidence yet for active volcanism on Earth’s neighbour planet.

Seeing the planet’s surface is extremely difficult due to its thick atmosphere, but radar observations by previous missions to Venus have revealed it as a world covered in volcanoes and ancient lava flows.

Venus is almost exactly the same size as Earth and has a similar bulk composition, so is likely to have an internal heat source, perhaps due to radioactive heating. This heat has to escape somehow, and one possibility is that it does so in the form of volcanic eruptions.

Some models of planetary evolution suggest that Venus was resurfaced in a cataclysmic flood of lava around half a billion years ago. But whether Venus is active today has remained a hot topic in planetary science.
ESA

Transient hot spots on Venus: Best evidence yet for active volcanism

Posted By Emily Lakdawalla

2015/06/18 23:42 UTC

Topics: pretty pictures, Venus missions before 2000, Venus Express, Venus, geology, explaining science

In a paper released in Geophysical Research Letters today, Eugene Shalygin and coauthors have announced the best evidence yet for current, active volcanism on Venus. The evidence comes from the Venus Monitoring Camera, which saw transient hot spots in four locations along a system of rifts near Venus’ equator. They saw the hot spots in two distinct episodes in 2008 and 2009.

The press release describes the science pretty well, so I won’t belabor that here; I thought I’d show you some pretty pictures of the region, made from Magellan data. Magellan obtained radar images of more than 97% of the planet, which have been merged into several enormous global data sets. To get the best-quality Magellan data you have to interact with an extremely klunky interface through the USGS, but it’s well worth the effort. Here is the region in which Shalygin et al. report observing the hot spots.

The Planetary Society

So this is what runaway AGW looks like. Anything to add ESA? Or the other lot? No?

The Soviets getting down more than once, with a camera, still rankles others as does relying on Russian supplied heavy lift engines. We are fortunate they did get there, drew a line in the sand dulling fictional imagination through clouds, remote sensing.

A question now is by how much do active volcanoes, probably very large, change what is supposed to be known about the Venus conditions?

Post by Tim

Comments
  1. “…by how much do active volcanoes, probably very large, change what is supposed to be known about the Venus conditions?”

    The comparison of Venus and Earth atmospheric temperatures, over the range of Earth tropospheric pressures, shows the Venus/Earth temperature ratio is a constant that is precisely determined by the two planets’ distances from the Sun, with no surface effect (such as the greenhouse effect with its “backradiation”). So surface volcanoes certainly do not affect the Venus atmospheric temperatures from about 50 km on up, and there is no reason they should affect the temperatures further down, as the constant lapse rate is not at all due to the amount of heat passing through it from the surface (and the greater the pressure, all the more stable should be the hydrostatic condition that alone sustains the lapse rate). If there are active volcanoes there, the heat gets out the same way it does on Earth: It rises naturally, “down” the temperature gradient, from surface to top of troposphere, basically by conduction (local stabilization of the hydrostatic pressure distribution), not convection or radiation. The very fact that they can “see” these hot spots tells us the heat from them is not lost to the atmosphere, but basically passes right through it.

  2. Some wavelengths must be fairly transmissive, Why do they not say what wavelengths avoid SO2, H2SO4, and CO2 absorption? ESA reports only a wide angle multispectral camera!

  3. tchannon says:

    It is an old spacecraft and mission, on the other hand it was designed knowing the conditions.

    We also need to consider the hostile space conditions nearer the sun for a prolonged mission. In addition it is a very thick atmosphere, camera signal to noise with I assume little cooling available would preclude high sensitivity.

  4. I finally found the bands used:
    F3 (uv-)___0.365 micron___0.04 micron fwhp__looking for O2
    F4 (vis-)___0.513 micron___0.05 micron fwhp__looking for nb visable
    F5 (nir1)___0.965 micron___0.07 micron fwhp__looking for H2O @ 70km
    F3 (nir2)___1.010 micron___0.02 micron fwhp__looking for H2O @<70km, sirface

  5. Brett Keane says:

    Will Janoschka says: harrydhuffman (@harrydhuffman) says:
    June 21, 2015 at 1:47 am
    June 21, 2015 at 3:19 am Maybe another hint to us of the hidden complexities of physics (oh well, to me anyway). There is something I’m trying to grasp about what the Venus-Earth comparison shows us re albedo/absorption/emissivity/optical depth. Apart from the wee fact that the gas laws rule of course, never ghg’s. A lab experiment we did re Beer-Lambert light extinction with minced-uo leaf chlorophyll suspended in water, keeps haunting me. It was designed to explore the effects of leaf area and depth on plant energy harvesting… Will – OT, but could you explain why and how you say that there is no atmospheric water as gas/vapour around Earth? Thanks, Brett PS- to all Poms, well done in the Cricket!

  6. Brett Keane says: June 21, 2015 at 5:43 am
    Will Janoschka says: harrydhuffman (@harrydhuffman) says:
    June 21, 2015 at 1:47 am
    June 21, 2015 at 3:19 am “… Will – OT, but could you explain why and how you say that there is no atmospheric water as gas/vapour around Earth? Thanks, Brett PS- to all Poms, well done in the Cricket!”

    When and where have I ever written such a thing?

  7. Brett Keane says:

    Will – in the convection post now ongoing, several times iirc. You seemed to be saying that, certainly in convective activity, it entered other phases. Perhaps in jest? Brett

  8. Brett Keane says: June 21, 2015 at 7:03 am

    Will – in the convection post now ongoing, several times iirc. You seemed to be saying that, certainly in convective activity, it entered other phases. Perhaps in jest? Brett

    Here or in convection point out such a thing! The atmosphere always contains much WV and airborne water condensate going back and forth from dayside to nightside!🙂

  9. wayne says:

    “I finally found the bands used:
    F3 (uv-)___0.365 micron___0.04 micron fwhp__looking for O2
    … ”

    Will, I’m drawing a blank on fwhp. At first that looked like a range but seems more like a different unit. Any help?

  10. Full width half power “bandwidth” 🙂

  11. Michele says:

    Precise date ?
    I want read full paper.

    Quote : “one fixed surface hot spot is inferred, labelled ‘Object A’, which shows an increase in brightness between 22 and 24 June 2008 followed by a decrease.”

    January-December 2008 on the earth (earthquakes M7.5 +)
    June is midway

    Bye,
    Mic

  12. wayne says:

    Will, ok, thanks, thats clear now. Aren’t many clear frequencies all of the way to the surface are there?🙂

    Take a peek at the chart i just posted on that “convection” thread. That might explain to you a bit clearer what I have been trying to get everyone to just consider what it seems to so clearly indicate.

  13. Mike Flynn says:

    Just as a matter of interest, if a body with a surface hotter than the environment is left alone, it will cool. If the core is hotter than the surface, it will cool.

    You can try this yourself. Heat an iron sphere until it is just below softening point. Surround it with anything you like. CO2, methane, the world’s finest insulating material, pixie dust, it doesn’t matter.

    Leave it in the Sun. You can’t stop the surface cooling. You can’t stop the core cooling. Eventually,it will reach the same temperature as an identical sphere you didn’t apply extra heat to, at all.

    If Venus is hotter than 4K, the surface will cool. Advection, heat from the Sun, clouds, CO2, nothing will stop it, until the body is isothermal throughout, beyond the influence of the Sun.

  14. blob says:

    There is still no explanation for Harry’s observation. It can only be chalked up to coincidence, which we all know as the “things” that build up to be explained until the current paradigm is dropped. Maybe it is a coincidence (I doubt it), but we need more undeniable observations like that.

  15. Brett Keane says:

    @blob says:
    June 27, 2015 at 7:19 am: Every solar system atmosphere measured by Nasa JPL etc, which is most of them, supports Harry’s hypothesis. That is, where they are thicker than our tropopause (i.e. not Mars); and above the super-critical high density layers of the gas giants. That albedo does not appear to matter, suggests that solar ‘hot’ IR does the job alone. So, phase changes such as that of water, and methane on Titan, seem to perform internal modulation to the return of energy to space, increasing efficiency but not altering long-term surface temperature means. It is mass, the particular mechanical properties of all fluid gases (the gas laws), and distance from the sun which rule. This understanding came to us around 2011, and the data has not been refuted.

  16. Brett Keane says:

    @blob: a couple more papers:
    THE “GREENHOUSE EFFECT”
    AS A FUNCTION OF ATMOSPHERIC MASS
    Hans Jelbring
    email: [mod: snip]

    Common 0.1 bar tropopause in thick atmospheres
    set by pressure-dependent infrared transparency
    T. D. Robinson and D. C. Catling

  17. Brett Keane says:

    @blob: and: Unifying Planetary Atmospheres
    By Chris Faesi ⋅ December 31, 2013 ⋅ Post a comment
    Filed Under exoplanets, habitability, planetary atmospheres, planetary science
    Paper: Common 0.1 bar Tropopause in Thick Atmospheres Set by Pressure-Dependent Infrared Transparency

    Authors: T.D. Robinson and D.C. Catling

    First Author’s Institution: NASA Ames Research Center, Moffett Field, CA

    Paper Status: Accepted to Nature Geoscience

  18. oldbrew says:

    It’s only a coincidence to those who for some reason adhere to the concept of planets as greenhouses – an obvious absurdity, as there are no similarities between planets and greenhouses.

  19. blob says:

    @Brett

    Thank you. I have actually read that paper earlier but I agree it is exactly the type of information we need to move forward. In fact, the reason it caught my eye in the first place was the Venus “coincidence”.

  20. blob says:

    Previous post was meant to be directed towards Brett Keane. I apologize for any offense. [fixed, mod]