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Venus: Stranger Than We Thought

2012/02/11 1 comment

Until now, there were many strange things already about Venus. Now, there is one more, with possible climate implications. From ESA’s Venus Express: Could Venus be shifting gear?

[…] ESA’s Venus Express spacecraft has discovered that our cloud-covered neighbour spins a little slower than previously measured. […]  Over its four-year mission, Magellan was able to watch features rotate under the spacecraft, allowing scientists to determine the length of the day on Venus as being equal to 243.0185 Earth days. . However, surface features seen by Venus Express some 16 years later could only be lined up with those observed by Magellan if the length of the Venus day is on average 6.5 minutes longer than Magellan measured. […]

A quick back-of-the-envelope calculation indicates that 6.5 minutes in 16 years translates in 1.56 watt per hour on each square meter of Venus’ surface, if all the rotational energy is converted into heat (I couldn’t double-check the results though). If this process is cumulative, it will certainly have huge consequences.

Venus Awakening

2010/05/07 9 comments

Steve Goddard in WUWT, May 7, 2010? Luboš Motl in the reference frame, same date?

Sure, but what about Omniclimate’s 4-part series starting Feb 27, 2008? (Here parts 2, 3 and 4)

Or Omnologos’ now ancient Aug 17, 2007 post?

Alas, there was some mention of it in a July 2007 Elsevier book. But who cares? What is important is that the stale orthodoxy about Venus’ “runaway greenhouse effect” is starting to dissipate.

As forecasted in “Venus Forecast” 35 months ago: “In a few years, the old ideas of Fred Singer will come back into fashion.

Venus’ retrograde rotation, incredibly massive atmosphere and relatively young (<500 million years) surface will be elegantly explained by the crash of a massive satellite half a billion years ago (with subsequent melting of much if not the whole crust, and humongous outgassing).

Current lead-melting surface temperatures will be just as beautifully explained by simple adiabatic processes.

The role of CO2 in the heating of the atmosphere via some “greenhouse effect” will be seriously reconsidered and almost completely dismissed.

UPDATE May 10: WUWT has a new post on Venus. Among the comments, a link to another blog making a similar point (Oct 7, 2009) and to a brief communication by Carl Sagan in the pages of the Astrophysical Journal (1967) estimating the surface temperature without a single mention of the “runaway greenhouse effect”.

Another Good Argument About The Greenhouse Venus Hypothesis

2009/03/23 6 comments

From JoNova’s “DeSmog accidentally vindicates The Skeptics Handbook

The next time a warmist yells Venus. Just yell back Mars. Its’ atmosphere is 95% carbon dioxide and yet, oops – it’s not 400 degrees, instead, it’s minus 40. The warmists with half a brain might come back at you with the explanation that Mars’s atmosphere is thin, but that’s just fine. That IS the point really isn’t it? Mars is cold because it’s atmosphere is so thin, and for exactly the opposite reason, that’s why Venus is Hot.

ps Hugs&kisses for linking to Omniclimate, of course! A list of my Venus-related blogs is available at this link.

Earth, then Mars…Venus Next in Line for “Giant Impact” Explanation

Big news today about Mars’ peculiar north-south terrain divide having been caused by the impact of a Moon-size object shortly after the planet formed. Since there is also strong evidence for Earth having undergone a similar impact, with a Mars-size planetoid, thereby forming our Moon, it would be odd to imagine that no such catastrophe ever occurred to Venus.

After all there’s lots still to explain about “Earth’s Twin”: a very slow retrograde rotation, an incredibly massive atmosphere and a relatively young (<500 million years) surface. To me, the whole setting cries out loud for an “impact” explanation, rather than the classic “it’s warm because of the CO2!” theory that says nothing about all the other peculiarities (and it’s not exactly necessary…).

Venus Atmosphere Still A Mystery

2008/03/26 5 comments

From Universe Today: “Although the bright haze of Venus’s atmosphere has been identified, many dark patches have also been observed. So far, there is no explanation for these patches of atmospheric chemicals absorbing solar UV“.

In the meanwhile, raypierre of RealClimate summarizes the latest info about the atmosphere of Venus, but somehow forgets to include the UV absorption mystery (it only shows up as an afterthought, comment #2).

One wonders why? Obsession with consensus and the need to demonstrate there exist such a thing as “climate science” spring to mind.

Venus and a Thicker-Atmosphere Earth

2008/03/06 4 comments

(fourth post in a series dedicated to the planet Venus as “example” of runaway greenhouse warming)
Venus post #1: Venus: Cool Greenhouse?
Venus post #2: Venus Warming Revisited
Venus post #3: Venus Missing Greenhouse Warming
Venus post #4: Venus and a Thicker-Atmosphere Earth

In reply to this comment

Ok n-g I presume we can now do assuming all niceties instead of repeating our thanks😎 so let’s try to clarify a few points.

To my mind, they act very differently

the rest of my question was “Wouldn’t moist convection for example drastically change the consequences of an increase in atmospheric CO2?”.

And the point was: when people say, look at Venus to see what GHG warming can do, the scientific answer should be that no comparison can be done with Earth as the whole mechanism of “warming” is very different (whatever CO2 may or may not be doing…if only because we have so much water vapor).

May I dare say we agree on this point?

When you’re looking at the planetary energy balance, the single number albedo is not just the starting point, but also the ending point

But surely an atmosphere, say, with low albedo in UV and high albedo to visible and IR does not behave as an atmosphere that is the other way around?

Earth’s for example is able to keep a bit warmer by the presence of UV-absorbing ozone in the stratosphere. That would mean a lower albedo in UV than in visible light, wouldn’t it?

The dry adiabatic lapse rate depends only on gravity and heat capacity

If the greenhouse effect is so strong on Venus, why isn’t the lapse rate much larger, and much larger than Earth’s, given the fact that the amount of CO2 decreases a lot between the surface and the height of 60km?

Surely the lower one gets, the more GHG there are, the higher the ability to trap heat.

Suppose there were no greenhouse effect on Venus

As you say, this is an argument, not proof

The fact that the IR emissions from Venus come from the atmosphere and not from the surface constitutes the proof

The fact that visible light comes from the atmosphere and not from the surface only proves there’s lots (lots!) of clouds on Venus. Why would the same observation regarding IR mean something else?

If the atmosphere of Earth were 100 times more massive

Let’s imagine Earth had a 10-km deep, reasonably large crater in the middle of a continent, with no liquid water on its bottom at all. What would be the temperature at the bottom of the crater? With a lapse rate for saturated air of 5.46K/km, 288+5.46*10=342K or 70C. Right? Wrong?

Venus Missing Greenhouse Warming

2008/03/02 8 comments

(third post in a series dedicated to the planet Venus as “example” of runaway greenhouse warming)
Venus post #1: Venus: Cool Greenhouse?
Venus post #2: Venus Warming Revisited
Venus post #3: Venus Missing Greenhouse Warming
Venus post #4: Venus and a Thicker-Atmosphere Earth

Let’s compute (in a simplified manner!) what would happen were Earth suddenly equipped with an atmosphere as massive as Venus’ (ie 90 times more than ours).

Given the similarities in mass and diameter of the two planets, we can assume this new atmosphere would behave similarly to Venus’, and in particular, purely adiabatically below 60km (instead of below 12km as at present).

For another simplification, let’s also imagine the new atmosphere to be just as our current one but without any water.

The lapse rate for dry Earth atmosphere is known and is 9.760 K/km.

How higher would the surface temperature be, with a dry atmosphere and a 60-km-thick troposphere?

9.760 * (60-12) = 468K higher than at present (288K)

The total for Earth is then 756K. Compare that to Venus’ surface temperature of 735K.

For an amazing coincidence, that’s 97% of the above, whilst the ratio of absorbed Solar radiation at Venus compared to Earth is… 96%.

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Note how the increase in temperature doesn’t depend on any greenhouse gas.

And so do we really need to believe in greenhouse warming when mere mass can explain the observations?

Venus Warming Revisited

2008/03/02 6 comments

(third post in a series dedicated to the planet Venus as “example” of runaway greenhouse warming)
Venus post #1: Venus: Cool Greenhouse?
Venus post #2: Venus Warming Revisited
Venus post #3: Venus Missing Greenhouse Warming
Venus post #4: Venus and a Thicker-Atmosphere Earth

In reply to Dr. John W. Nielsen-Gammon‘s comment published at Eric Berger’s SciGuy blog entry “Is the global temperature now falling?

I am the author of the Venus blog originally pointed out in a comment by Jim Mayeu.

I am all for understanding the behavior of atmospheres and the reasoning behind current scientific theories. Chances are, I have not discovered anything major, or nothing at all. But do allow me to probe this further.

(1) First question that springs to mind is, if the terrestrial and venusian atmospheres behave so differently, how could any “greenhouse effect” act similarly in both? Wouldn’t moist convection for example drastically change the consequences of an increase in atmospheric CO2?

Is it a matter then of asking people that mention Venus when talking of anthropogenic global warming, to please shut up in the name of Science?

(2) Also, the “albedo” as a single number for a whole planet is a good approximation to start from, but once again the differences between those atmospheres will surely reflect in different albedo/radiation frequency curves (not to mention how solar radiation diminishes the nearer it gets to the planetary surface).

(3) But let’s go back to the whole adiabatic business.

Lapse rates depend on gravity, and the heat capacity of the atmosphere. Gravity is similar between Venus and Earth, and CO2 responds to compression in a manner similar to air. Is that not enough to expect a similar lapse rate?

In fact, or at least in theory, the “dry” values are:

Venus: 10.468 K/km
Earth: 9.760

In practice, the Pioneer-Venus descent probes actually measured a lapse rate of 8K/km between 60 and 10km above the venusian (or shall I say, Cytherean) surface, and of around 2 between 120 and 60km.

Under normal conditionson Earth the lapse rate is assumed to be around 6.38, with a maximum for “dry” air of 10 and a minimum for 100% saturated air of 5.46.

(4) The “energy balance” computation you mention simply assumes a specific “greenhouse effect”. But we cannot use the thesis to demonstrate the hypothesis, so to speak.

All we know is that in terms of flux at the surface, there are 500K left to be explained.

For example, has anybody tried to compute the Earth’s surface temperature with 90-100 times more atmospheric pressure than it has, or better yet, Venus’s with 90-100 times less? (chances are, somebody has done that already). Any “greenhouse effect” would be on top, not instead of that.

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The elegance of the Fred Singer’s “explanation” recently partially revisited by John Huw Davies, a geodynamicist at Cardiff University in the UK, is after all the fact that it considers all of the Venus’ peculiarities.

Otherwise, we must imply it’s only by chance that the hottest temperatures belong to the youngest surface, in the one planet with an almost perfectly retrograde rotation (Uranus’ axial tilt is 98deg, Venus’ 177.36deg).

That’s 2.64deg away from the planet’s orbital plane’s vertical. If such a “coincidence” doesn’t scream for an explanation, I don’t know what does.

Venus: Cool Greenhouse?

2008/02/27 20 comments

(originally published as “Venus Forecast” on Aug 17. 2007):

(first post in a series dedicated to the planet Venus as “example” of runaway greenhouse warming)
Venus post #1: Venus: Cool Greenhouse?
Venus post #2: Venus Warming Revisited
Venus post #3: Venus Missing Greenhouse Warming
Venus post #4: Venus and a Thicker-Atmosphere Earth

In a few years, the old ideas of Fred Singer will come back into fashion.

Venus’ retrograde rotation, incredibly massive atmosphere and relatively young (<500 million years) surface will be elegantly explained by the crash of a massive satellite half a billion years ago (with subsequent melting of much if not the whole crust, and humongous outgassing).

UPDATE FEB 28 2008: Space.com: Venus Mysteries Blamed on Colossal Collision

Current lead-melting surface temperatures will be just as beautifully explained by simple adiabatic processes.

The role of CO2 in the heating of the atmosphere via some “greenhouse effect” will be seriously reconsidered and almost completely dismissed.

========

Some quick computations:

Ratio of available solar energy Venus/Earth: 190%

Earth, surface pressure: 1000 mbar; temperature: 288K
Venus, 50km altitude pressure: 1000 mbar; temperature: 330K
330K/288K = 114% < 190%

Venus, surface pressure: 90,000 mbar; temperature: 735K
Temperature of terrestrial air compressed from 288K/1,000mbar to 90,000mbar: 887K
735K/887K = 82.9% < 190%

Far from showing any CO2-induced global warming, Venus is much cooler than expected, likely because of the high-altitude clouds that prevent us from looking at the surface.

Why the NASA Planetary Atmospheres Website Doesn’t Mention Greenhouse Gases

2008/07/21 10 comments

Discussions with people holding a different view are obviously quite likely to help bring one’s reasoning forward (as long as there is no name-calling or other infantilism).

For an example of what can happen, look no further than this exchange with Ed Darrell at his Millard Fillmore’s Bathtub. The topic is, what is the relevance of the fact that the NASA Planetary Atmospheres website (PDS-A) doesn’t mention greenhouse gases.

To which my answer has been:

if the experts in the field don’t take it into consideration, I surely want to know why!!

Ed has replied with an interesting suggestion:

The site doesn’t pretend to be an exhaustive resource for all studies of all atmospheres everywhere. It’s a site to get a line into work NASA has actually done.

But if that’s true, it means that in all these years, NASA has seldom if ever looked at ways to investigate the same greenhouse effect that keeps Earth’s average temperature above freezing, and Venus with a surface temperature higher than an oven. And furthermore, there is a dearth of data in this most practical of planetary atmospheric fields!!

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Let’s try to figure out if Ed’s interpretation is right. In its About page, the PDS-A site says “As an additional service, the Atmospheres Node provides information on relevant planetary atmospheres topics for educational purposes”.

There are links for Educators, including to the NASA Planetary Data System College Student Investigators (CSI) webpage that states

The objective of this activity is to involve undergraduate students in research and development projects related to the holdings of NASA.s Planetary Data System (PDS). Through the PDS College Student Investigators activity, the PDS strives to prepare the next generation of PDS science investigators.

A recent proposal is about investigating the role of dust in the thermodynamics of the Martian atmosphere. Neither there nor elsewhere there is any mention of greenhouse gases, a topic that evidently and mysteriously does not interest “next generation of PDS science investigators”.

Going back to PDS-A, there are educational links also to “Broker Forums“. One of them is the web site for the “Sun-Earth Connection” at NASA’s Goddard Spaceflight Center, curiously linking to another website “Space Weather” containing a few unorthodox remarks on the Sun and Earth’s climate.

Another link for the Broker Forums goes to NASA’s Solary System Educational website where (finally!) there is some serious content about the greenhouse effect (GH).

And what does that refer to? Step forward ESA’s Venus Express, that lists among its scientific objectives the investigation of

what is the role of the radiative balance and greenhouse effect in the past present and future evolution of the planet?

==============

Chapeau to Ed Darrel, then…for all intents and purposes, NASA has dedicated no mission to the study of the greenhouse effect. That’s why there is no mention of it in the PDS-A site, the Planetary Data System for Atmosphere: simply, there is no data to report. Because nobody ever looked for those.

Is the current state of Climatology on this planet and everywhere else sad or what? If Goddard’s Director and climate worrier James Hansen is unable to gather funds for a terrestrial or planetary mission on the greenhouse effect; or worse, if even he is not interested enough to put one together: then how solid will the science of the climate ever be?

ps Still, the PDS-A Encyclopedia could have had a page on the GH effect. Its equations albeit simplified, still are possible

NASA Planetary Atmospheres Website Doesn’t Mention Greenhouse Gases

2008/07/15 6 comments

Looks like there is at least one NASA website dedicated to planetary atmospheres, that cares not a zilch about the greenhouse effect.

The Planetary Atmospheres Node (Atmospheres Node, or Atmos) of the Planetary Data System (PDS) is responsible for the acquisition, preservation, and distribution of all non-imaging atmospheric data from all planetary missions (excluding Earth observations). The primary goal of the node is to make available to the research community the highest quality data possible. To this end, data are reviewed and re-formatted where necessary in order to meet the documentation and quality standards established by the PDS

The Education/Outreach section at least, says nothing at all about the greenhouse effect, whilst going into the details of lots of other things, such as how to compute the adiabatic lapse rate (dry).

CO2 and “greenhouse” are vaguely mentioned in few of the Abstracts but for some reason haven’t made it to the Education pages.

ADDENDUM: I am discussing the above with Ed Darrell at his Millard Fillmore’s Bathtub.

ADDENDUM (2): It seems that we have an answer. That site doesn’t mention the GH effect because no interplanetary probe has bothered yet to study it. Things may be a-changing with ESA’s Venus Express.

On Satellite Observations and Climate Change

2008/07/08 7 comments

An open letter to the Planetary “Sponsored Global Warming” Society

Dear Directors of the Planetary Society, dear Editors of the society magazine “The Planetary Report”

Your decision to dedicate a whole issue of the Planetary Report magazine to Planet Earth is commendable.

Too often one forgets that for the study of the universe there is a celestial body available to study 24/7, without the need for expensive trips to outer space. And that “body” is our own planet, the “cradle of humanity”.

All “missions to planet Earth” in the forms of orbital satellites and probes are worthwhile almost de facto, as new data can help us better understand our “motherworld”, and together with the accompanying experience may allow us to build the satellites and probes needed to explore the rest of the Solar System, and beyond.

But the July/August issue of the Planetary Report is not a celebration of past “missions to planet Earth” nor a comprehensive description of all the challenges lying ahead, and of all the questions still unanswered about our planet.

It’s just a collection of articles about global warming.

Is that what I and surely many other members await two long months for, every time? (and yes, I do follow Emily Lakdawalla’s blog).

Let’s assume “global warming” is indeed a big planetary issue, if not an emergency. Is it not talked about already in countless newspaper articles, movies, Nobel Prize wins, parliamentary sessions the world over, and now even a major topic of discussion at the G-8 “major industrialized nations” meeting?

And what purpose could it ever serve for a space-advocacy group to throw in its lot, especially since the issue has become so heavily politicized? Then one reads behind the magazine’s cover, and the “partial sponsorship” by Northrop Grumman Corporation starts explaining things.

After all, They are definitely not the first ones to jump on the “global warming bandwagon”, as demonstrated by a recent article on the International Herald Tribune. In the Planetary Report, they are the Company using the picture of a polar bear to advertise on the back cover that their “satellites above are safeguarding life below”.

Too bad though, Northrop Grumman Corporation wouldn’t survive a week by sticking to the environmental satellites market, and has to build some other pieces of hardware far less safeguarding for the lives experiencing a close encounter with their weapons.

But the problem is not with Northrop Grumman. The issue is what is the Planetary Society doing by jumping head first in the “global warming” debate, and also how it is doing it: because oversimplifications and mistakes abound. And that is definitely a no-no for something like the Planetary Society, that bases all its work of course on Science and on precision.

Here a quick list of observations:

(1) Contrary to what the Editor Charlene M. Anderson writes in the opening column, the Earth’s climate is not being recorded as undergoing a “steady warming”. There has been no warming in the past 10 years. Previous decades have seen warming and cooling episodes. If we are undergoing a warming, it’s definitely “not steady”

(2) In “Earth is, after all, a planet”, Charles F Kennel talks about “moving from knowledge to action”, because “human actions change our planet in ways that are not beneficial”. Note that certitude in those words. Does Mr Kennel realize that those words could be used to demonstrate there is no real need for more satellites to observe our planet? On the other hand: if the “global perspective” can “be found only in space” and therefore more satellites are needed indeed, what is the certitude on global warming based upon?

(3) Editor Charlene M. Anderson is then back in action with a “Venus and Mars, Earth’ s sister worlds” box making improbable connections between Venus’s clouds of sulphuric acid and acid rains on Earth (the two phenomena have little in common apart from elementary chemistry) and between Mars’s tenuous atmosphere and the Antarctic “ozone hole” (UV levels for the former are way higher than for the latter).

(4) In the same piece, we are told that Mars and Venus have shown us how “fragile, precious and unique” Earth is: I am not sure how anybody familiar with the evidence of periodical “asteroidal bombardments” on the surface of the vast majority of solar system bodies could define Earth as “fragile”, given that it has deleted almost all traces of four billion years of impact.

(5) Finally some fresh air in Michael D King’s “The Earth’s changing environment as seen from space” that actually is a list of all that can be done with satellites to monitor our planet. King’s piece is a good reminder of what it means to stick to the facts, instead of trying to “knit” one’s preferred interpretation around them. On the same tone, Editor Charlene M. Anderson’s box “Here, there and not quite everywhere” about analogies (rather than forecasts of doom) between what is seen on Earth and what happens on other planets and on natural satellites.

(6) Things turn to the worse with 6 pages given to Richard J Sommerville to explain the results of the Intergovernmental Panel on Climate Change (IPCC). We are told that it is “90% certain” that us humans have caused “Earth’s atmosphere to warm up in recent decades” by emitting “greenhouse gases” in all our activities: too bad there is no space to explain where is this 90% figure coming from, for example why not 85.6% or 92.4%. We are just told it means “very likely” (why not stick to those words then).

(7) Furthermore, in the section “Recognizing climate change” Sommerville does nothing of the sort, and instead further dwells in the IPCC statements, before listing a rather selective group of observations (he forgets to mention the expansion of Antarctic ice, for example). And then after stating that “the IPCC does not specifically forecast what the climate will do”, Sommerville nevertheless writes that “sea level will rise perhaps by 18 to 59 centimeters”, with uncertainties due to scientists being unable to “assess the potential for further sea level rise”. Perish the thought of being unable to assess the potential for lower-than-expected sea level rise…

(8 ) In section “Absolute certain truth” we are told that the IPCC is “simply an honest and competent assessment of published peer-review science”. Hopefully so. But then on what basis did the IPCC get the Nobel Peace Prize? Not to mention the fact, reported by Sommerville, that the IPCC Working Group reports are approved line-by-line by governmental representatives.

The IPCC must have performed the miracle of uniting “honest”, “competent” and “government” under the same roof for the first time in history.

(9) The pictures accompanying Sommerville’s articles seem chosen for old-style PR purposes. There is a refinery emitting gases (those are not greenhouse gases); impressive satellite pictures before and after cyclone Nargis (that had nothing to do with climate change); and another satellite picture of the Ross ice shelf in Antarctica seemingly breaking up into icebergs (there is little indication that the southernmost continent is warming at all, apart from its Peninsula).

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Ironically, there are other ways to advocate for more “missions to planet Earth”, rather than parroting the most trite global warming slogans.

For example, there is no mention in the Planetary Report issue of the first chapter of the IPCC’s Working Group Two report, where it is clearly shown that the overwhelming majority of data confirming the climate is changing come from Europe alone.

We are talking 96% of evidence coming from 7% of the planet’s land area.

A major Earth observation plan is definitely in order: for the most basics of reasons, in order to observe and understand what is truly happening. If the first step instead is to declare our knowledge more or less settled, a couple of satellites will suffice.

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(10) As Berrien Moore III writes in the final article “As riders on the Earth together”, “to act wisely we require information and understanding”. Whoever is worried about global warming, they better concentrate on getting more environmental satellites up there, instead of declaring as a matter of principle that “we simply must take some of the pressure off Earth” as Mr Moore unfortunately states at the end of his article.

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Tellingly, we Members of the Society are not provided anything else from this issue of the Planetary Report. No Society news, no items on sale, no information about upcoming events, nothing about existing projects. Perhaps those folks at Northrop Grumman didn’t want to pay for the additional couple of pages. Or perhaps if climate change is afoot, all other activities of the Society will not be of interest any longer.

regards

maurizio morabito – london (uk)

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