Global warming milestone about to be passed and there's no going back.

originally posted by: Phage3) Oceanic pH levels are decreasing. This indicates that the ocean is absorbing CO2, not releasing it.

Is it even possible for us to measure ocean pH with any degree of reliability? I mean, for one thing, just think how big the damn ocean is. How many measurements of the ocean have we taken and how much of the ocean have we measured? I imagine there's some serious extrapolation involved. According to Wikipedia "Seawater pH is typically limited to a range between 7.5 and 8.4. However, there is no universally accepted reference pH-scale for seawater and the difference between measurements based on different reference scales may be up to 0.14 units". Also, pH is not just dependent on the concentration of aqueous CO2. There are other factors that can change pH, such as eutrophication/degradation, temperature, and land-based effluents. Also, even if the oceans are releasing CO2, they still could have absorbed more CO2 from human emissions than they have released. Humans have emitted about 2000 Gts of CO2 since 1850 according to the IPCC and the increase in CO2 has only been about 940 Gts. Hence the oceans must have absorbed more CO2 from humans, even if they have contributed significantly to the CO2 increase.

originally posted by: Phage2) The changes in the isotopic signature of atmospheric CO2 indicate that; a) it's origin is plant material b) it's origin is very, very old plant material. Not the ocean.

94% of all CO2 in the atmosphere is in fact isotopically-indistinguishable from natural CO2. Currently at the δ13C permil value of -8.3 about 6% (as a maximum) of CO2 in the atmosphere can be attributed to humans. The decrease in 14CO2 in the atmosphere is not proof that the increase in CO2 is anthropogenic because 14CO2 in the atmosphere would be expected to decrease simply by virtue of our emissions increasing and the atmospheric CO2 mass increasing.

a reply to: Nathan-D

As someone mentioned in this thread, pressure is proportional to temperature. If you increase pressure, temperature increases.

Yes. Is the surface pressure on Venus increasing?

This constant cycle I imagine would be possible on a planet because of convective overturning.

How so? How does convection affect pressure? Doesn't warm air rise because it is less dense that the surrounding air?

How can the greenhouse effect be maintaining such high temperatures at night when it is dependent on solar radiation to operate and when the night-side is not seeing any solar radiation for such prolonged periods?

The greenhouse effect prevents heat from escaping into space. That's sort of the point.

Also, even if the oceans are releasing CO2, they still could have absorbed more CO2 from human emissions than they have released.

Yes. The oceans are absorbing more CO2 than they are releasing. That means that the oceans cannot be responsible for increasing atmospheric CO2 levels. That's the point.

originally posted by: PhageYes. Is the surface pressure on Venus increasing?

Not to my knowledge. But as mentioned, there's a relationship between pressure and temperature. This described by the Ideal Gas law: PV = nRT. Where P is pressure, V is volume (1000 litres/m^3 here), n is the density/molecular mass, R is the Universal Gas constant (0.08314) and T is the absolute temperature. According to the Ideal Gaw law, from the pressure, molecular mass and density, we should expect a temperature on Venus of T = PV/nR = 92000*1000/(65000/43.45*0.08314) = 739.7°K. So, the temperature on Venus can be accounted for by pressure and no greenhouse is needed. See here/here. If the greenhouse was the main cause of the high temperatures on Venus then this would require CO2 to absorb 65 W/m2 (that is the solar radiation averaged out over the surface) and that 65 W/m2 would need to be amplified to 16,700 W/m2. But CO2 is an inert body and cannot create additional energy. It cannot re-radiate more energy than it absorbs.

originally posted by: PhageHow so? How does convection affect pressure? Doesn't warm air rise because it is less dense that the surrounding air?

The convection is what allows for the continuous compression of the atmosphere. As these atmospheric gases warm they expand, rise and then fall in the planet’s gravitational field, and as they fall they compress the atmospheric column below doing ‘work’ and heating it adiabatically.

originally posted by: PhageThe greenhouse effect prevents heat from escaping into space. That's sort of the point.

If the greenhouse effect were main source of heat (and the greenhouse effect is dependent on the Sun to operate) then shouldn't we would expect Venus to lose a good amount of heat over the 120 days that it is not receiving any sunlight? But this doesn't appear to be the case. The night side and day side are essentially the same temperature. This leads me to believe that there is another source of heat besides the greenhouse, and that source of heat I think could be pressure.

originally posted by: PhageYes. The oceans are absorbing more CO2 than they are releasing. That means that the oceans cannot be responsible for increasing atmospheric CO2 levels. That's the point.

Well, I think this depends if you agree with the IPCC's carbon-cycle figures showing how much the oceans are absorbing/releasing. I don't agree with them myself.

a reply to: intergalactic fire

But who is going to control this? We hear the same going on for ages with the GBR(great barrier reef), all the scare that it's dying, yet the GBR is in perfect shape. Sry not buying into this.

The Great Barrier Reef is not really fine... It is dying.. they have pictures.....

www.washingtonpost.com...

www.stuff.co.nz...

Asking who is going to control it is different than recognizing there is a problem in the first place... There is a problem... People are too busy arguing that it is not their fault... I don't understand how we blame nature, when the industrial Revolution and all the pollution were anything but natural... The earth is an ecosystem... A sphere with a specific volume called the atmosphere.. Adding or removing something from the system changes the system. Add X amount of a gas above that which is the natural process for 150 years and remove a large portion of the components that take that gas out of the air.. Repeat with thousands of other gases.. We have to add time in as a variable as well. Change is more possible than no change. In this case, it is warming of the system which is our planet. It is a simplification, but it is being discounted because of the belief that the Earth will fix itself and we can not effect the natural cycle. We believe the people who tell us it is not happening that make money selling us the things that add to the problem.. And we disbelieve those who tell us it is a problem now, because they might make money later with taxes, because we don't trust those guys. They have a motive to mislead people. But we know the biggest motive for this is money...

www.bloomberg.com...

You don't have to buy it... you already bought it.... They sold it.. The question is... Can you look without a preconceived notion of what is? A wise man knows he knows nothing, for if we think we know, we can not be open to new information. Science is not perfect... It was never meant to be.. It was about learning.... Scientific Method.... It is why looking at what they thought 10 years ago is logical but know that they were looking at something they were trying to understand... Look at their conclusions now as well. they never stopped working... people just stopped listening...

a reply to: Orionhunter88

research previous bleaching of coral reefs and you will find most of them have returned to their original state. I'd say it's just a scare. At least that's what marine biologist professor Peter Ridd says who'd studied the GBR. But you don't have to believe it, he is probably owned by oil corporations.

a reply to: intergalactic fire

Do you not want to reply to my last post?

a reply to: WeAre0ne

I've given my opinion in a comment to Phage.

a reply to: Nathan-D

So, the temperature on Venus can be accounted for by pressure and no greenhouse is needed.

No. The formula tells us the relationship between pressure, volume, amount (in moles), and temperature. It does not say one "accounts" for the other. Perhaps you can explain how the molar value for that liter of Venusian air was derived?

If the greenhouse was the main cause of the high temperatures on Venus then this would require CO2 to absorb 65 W/m2 (that is the solar radiation averaged out over the surface) and that 65 W/m2 would need to be amplified to 16,700 W/m2.

I don't know where how you arrive at that "amplificiation" value but there are elements additional to CO2 involved. lasp.colorado.edu...

The convection is what allows for the continuous compression of the atmosphere. As these atmospheric gases warm they expand, rise and then fall in the planet’s gravitational field, and as they fall they compress the atmospheric column below doing ‘work’ and heating it adiabatically.

As the gasses rise they and expand they cool (per the law you stated above). There is no net change in heat. There is no "continuous compression", there is a cycle. What you are saying would be the equivalent to overunity.

If the greenhouse effect were main source of heat (and the greenhouse effect is dependent on the Sun to operate) then shouldn't we would expect Venus to lose a good amount of heat over the 120 days that it is not receiving any sunlight? But this doesn't appear to be the case.

The greenhouse effect prevents heat from escaping into space. But also, the winds of Venus are consistent westerlies and very fast, rapidly transporting heat across the planet.

a reply to: intergalactic fire

Thanks for conveniently ignoring my questions. I think you got backed into a corner and that is your only way out.

a reply to: WeAre0ne

No, I hate repeating myself.
Getting too old and too long living on the stinking planet full of imbeciels, wish i could go back too the 60s, when life was an adventure.
Now answer my question, what do you care?

a reply to: intergalactic fire

That is total bullstuff. I am in the Florida keys right now, and myself and thousandsof 'conchs' can tell you the coral bleaching problem is real and serious.

I feel like you just want to down play the damage man is causing to this planet. The ignorance in regards to the environmental problems we cause upsets me.

originally posted by: Nathan-D

originally posted by: PhageYes. Is the surface pressure on Venus increasing?

Not to my knowledge. But as mentioned, there's a relationship between pressure and temperature. This described by the Ideal Gas law: PV = nRT. Where P is pressure, V is volume (1000 litres/m^3 here), n is the density/molecular mass, R is the Universal Gas constant (0.08314) and T is the absolute temperature. According to the Ideal Gaw law, from the pressure, molecular mass and density, we should expect a temperature on Venus of T = PV/nR = 92000*1000/(65000/43.45*0.08314) = 739.7°K. So, the temperature on Venus can be accounted for by pressure and no greenhouse is needed.

Where did that pressure come from?

So, why doesn't the super hot atmosphere radiate away its excess heat to space and lower the pressure and temperature simultaneously?

originally posted by: PhageAs the gasses rise they and expand they cool (per the law you stated above). There is no net change in heat. There is no "continuous compression", there is a cycle. What you are saying would be the equivalent to overunity.

That's a reasonable enough objection and I think that's the view most people take. I actually had a debate with someone about this some months ago. I would argue that the gravitationally induced pressure heat observed in stars and also on Jupiter would be active on other planets albeit to a lesser degree. Think about how stars are formed. They have nothing at their disposal apart from a bunch of molecules and gravity. And just with those things they're able to increase in temperature from essentially –273K to 10,000K (the temperature necessary for fusion). Before any chemical reaction, the temperature increase of stars, and also gaseous planets such as Jupiter, is created when the gases are compressed due to gravity. By my understanding, it is the sheer mass of the atmosphere pressing down on the molecules at the surface that increases their temperature by decreasing volume. Imagine a gas molecule at the centre of Jupiter compressed by the weight of the atmosphere above. It essentially has nowhere to go and pings around faster and faster until it manages to escape upwards, by which time it has more kinetic energy than the kinetic energy it had previously acquired by descending in the planet's gravitational field. I see no reason why this process should apply only to gaseous planets and not to any body with a large enough gravitational field. (Of course the molecule would lose that energy by the time it has reached higher in the atmosphere since it would collided with other molecules on its way up).

originally posted by: PhageThe greenhouse effect prevents heat from escaping into space. But also, the winds of Venus are consistent westerlies and very fast, rapidly transporting heat across the planet.

According to NASA the winds at the surface are 0.3 to 1.0 meters per second.

originally posted by: PhageNo. The formula tells us the relationship between pressure, volume, amount (in moles), and temperature. It does not say one "accounts" for the other. Perhaps you can explain how the molar value for that litre of Venusian air was derived?

Again, that's a reasonable objection. But if the temperature on Venus can be calculated correctly from simply pressure, density and molecular mass, then I would argue that we really have no need to invoke back-radiation.

originally posted by: PhagePerhaps you can explain how the molar value for that litre of Venusian air was derived?

Not sure what you mean here.

originally posted by: PhageI don't know where how you arrive at that "amplificiation" value but there are elements additional to CO2 involved. lasp.colorado.edu...

In the first paragraph of the PDF it gives 75% of solar radiation reflected by clouds, whereas the actual number seems closer to 84%. That seems like an error to me. The solar insolation for Venus is 2601.3 W/m2, and therefore incoming solar radiation averaged out over the surface on Venus is 650 W/m2 without albedo. Taking albedo into account this reduces to 65 W/m2. NASA gives an albedo for Venus of 0.9. So, I make that 84%, unless there is another source of reflectivity on Venus besides clouds, but I find that hard to imagine since the planet is blanketed in clouds many kilometers thick. The PDF gives 420K for the greenhouse warming from CO2, which works out at 1764 W/m2. So that's still an insane amplification factor. I mean, I don't know about anyone else here, but I would think that a CO2 molecule could not re-radiate more energy than it absorbs. If it is absorbing only 65 W/m2, then how is it re-radiating 1764 W/m2? I would think the 1st law of thermodynamics might have something to say about that. Assuming it's possible, why don't we just solve our energy-crisis by simply taking loads of CO2, adding some sunlight, and then living off the massive amplification of energy?

a reply to: Nathan-D

nssdc.gsfc.nasa.gov...

Bond Albedo 0.77

I mean, I don't know about anyone else here, but I would think that a CO2 molecule could not re-radiate more energy than it absorbs.
If it is absorbing only 65 W/m2, then how is it re-radiating 1764 W/m2?

Firstly, 2601 * 0.23 = 598 W/m^2 for the 'face on' 2-d cross sectional area.

Clearly the total outgoing to space non-optical radiation is close to 598 W/m^2. The extremely high greenhouse effect makes the equilibrium surface temperature very high of course. This will radiate from the ground a substantially high black body flux, but from the surface's point of view, the thick atmosphere is radiating down almost as much back. The radiation is bouncing up and down.

originally posted by: mbkennel
If it is absorbing only 65 W/m2, then how is it re-radiating 1764 W/m2?

I'm gob-smacked! NASA changed the albedo of Venus again! This pretty much discredits NASA as a credible source for me. Before 2012 the albedo for Venus was 0.75 and then they changed it to 0.9, and now it's 0.77. Just to prove that it was previously 0.9 Google 'NASA Fact sheet albedo 0.9 Venus' and go to page 2. So, total absorbed solar radiation by CO2 would be 2600/4*0.23 = 149.5 W/m2. NASA must have only changed the bond albedo very recently because Wikipedia is still using 0.9: en.wikipedia.org... Shame we can't see when it was changed.

a reply to: Nathan-D

Wouldn't NASA openly produce their equations, assumptions, changes/addendum, etc.? Maybe in an appendix? If something has truly changed and it's on the down-low that would be rather egregious (btw I haven't read any of the math/assumptions from NASA).

a reply to: Nathan-D

dp