If this is true,with the biomass photosynthesis of CO2 and converting it to oxygen, it would seem to point to a self regulating effect of the biosphere on climate.The new study goes with this item reported on WUWT in June 2008.
Surprise: Earths’ Biosphere is Booming, Satellite Data Suggests CO2 the Cause
The SeaWiFS instrument aboard the Seastar satellite has been collecting ocean data since 1997. By monitoring the color of reflected light via satellite, scientists can determine how successfully plant life is photosynthesizing. A measurement of photosynthesis is essentially a measurement of successful growth, and growth means successful use of ambient carbon. This animation shows an average of 10 years worth of SeaWiFS data. Dark blue represents warmer areas where there tends to be a lack of nutrients, and greens and reds represent cooler nutrient-rich areas which support life. The nutrient-rich areas include coastal regions where cold water rises from the sea floor bringing nutrients along and areas at the mouths of rivers where the rivers have brought nutrients into the ocean from the land.
See an animation of the Earth;s Biosphere: 512×288 (30 fps) MPEG-1 10 MB. More here at NASA SVS
More oxygen – colder climate
From the University of Copenhagen news release. 9 September 2009
Using a completely new method, researchers have shown that high atmospheric and oceanic oxygen content makes the climate colder. In prehistoric times, the earth experienced two periods of large increases and fluctuations in the oxygen level of the atmosphere and oceans. These fluctuations also lead to an explosion of multicellular organisms in the oceans, which are the predecessors for life as we know it today. The results are now being published in Nature.
Everybody talks about CO2 and other greenhouse gases as causes of global warming and the large climate changes we are currently experiencing. But what about the atmospheric and oceanic oxygen content? Which role does oxygen content play in global warming?
This question has become extremely relevant now that Professor Robert Frei from the Department of Geography and Geology at the University of Copenhagen, in collaboration with colleagues from Departamento de Geologı´a, Facultad de Ciencias in Uruguay, Newcastle University and the University of Southern Denmark, has established that there is a historical correlation between oxygen and temperature fluctuations towards global cooling.
The team of researchers reached their conclusions via analyses of iron-rich stones, so called banded iron formations, from different locations around the globe and covering a time span of more than 3,000 million years. Their discovery was made possible by a new analytical method which the research team developed. This method is based on analysis of chrome isotopes – different chemical variants of the element chrome. It turned out that the chrome isotopes in the iron rich stones reflect the oxygen content of the atmosphere. The method is a unique tool, which makes it possible to examine historical changes in the atmospheric oxygen content and thereby possible climate changes.
“But we can simply conclude that high oxygen content in seawater enables a lot of life in the oceans “consuming” the greenhouse gas CO2, and which subsequently leads to a cooling of the earth’s surface. Throughout history our climate has been dependent on balance between CO2 and atmospheric oxygen. The more CO2 and other greenhouse gases, the warmer the climate has been. But we still don’t know much about the process which drives the earth from a period with a warmer climate towards an “ice age” with colder temperatures – other than that oxygen content plays an important role. It would therefore be interesting to consider atmospheric and oceanic oxygen contents much more in research aiming at understanding and tackling the causes of the current climate change,” says Professor Robert Frei.
The results Professor Frei and his international research team have obtained indicate that there have been two periods in the earth’s 4.5 billion year history where a significant change in the atmospheric and oceanic oxygen content has occurred. The first large increase took place in between 2.45 billion years and 2.2 billion years ago. The second “boost” occurred for only 800 to 542 million years ago and lead to an oxidisation of the deep oceans and thereby the possibility for life to exist at those depths.
”To understand the future, we have to understand the past. The two large increases in the oxygen content show, at the very least, that the temperature decreased. We hope that these results can contribute to our understanding of the complexity of climate change. I don’t believe that humans have a lot of influence on the major process of oxygen formation on a large scale or on the inevitable ice ages or variations in temperature that the Earth’s history is full of. But that doesn’t mean that we cannot do anything to slow down the current global warming trend. For example by increased forestry and other initiatives that help to increase atmospheric and oceanic oxygen levels,” explains Professor Robert Frei, who, along with his research team, has worked on the project for three years so far.
Oh great!!! Now the AGW crowd will blame increased C02 on increased plant life, increased O2 and therefore … Global Cooling!
Pretty amazing to see the effect that the Congo River has all the way across the Atlantic Ocean.
“I don’t believe that humans have a lot of influence on the major process of oxygen formation on a large scale or on the inevitable ice ages or variations in temperature that the Earth’s history is full of.” That was an interesting comment made by Professor Robert Frei?!
Let me guess? The role of atmospheric oxygen has not yet been factored in to the GCM’s?
Al Pipkin (16:56:16) :
Oh great!!! Now the AGW crowd will blame increased C02 on increased plant life, increased O2 and therefore … Global Cooling!
As the subject of Oxygen already has been claimed as the “next scare” I would not worry too much about that.
Especially because your remark contains a contradiction:
We are still in a learning process, trying to understand the complex system that creates our climate.
Hopefully we will get the answers before we are send back into the Medieval Ages thanks to Collective Ignorance and Marxist Loons.
There were at least two other periods of very high oxygen levels.
300 million years ago during the Carboniferous which contained an ice age, low CO2 and very high vegetation output (lots of coal and oil comes from this period). O2 may have been as high as 35% of the atmosphere and forest fires would have been unstoppable without lots of rain.
100 million years ago during the Cretaceous when O2 was as high as 30%, CO2 was relatively low and temperatures were likely the highest in Earth’s history that we know about (4C higher than the PaleoEocene Thermal Maximum). Lots of oil and coal comes from this period as well. Sea levels may have risen 250 metres above today and flooded 20% of the continents.
So I’m not sure this proposition really holds throughout the record.
The press release still seems to focus on “greenhouse gas” as primary regulator of the earth’s climate, though affected by oxygen level.
So, oxygen may have as much of a positive effect on cooling as C02 has on warming; meaning, very little. “Increased forestry” sounds good in theory, not sure it has much practical value. How about better forestry practices, and not cutting or burning down rain forests to grow bio-fuels?
“The more CO2 and other greenhouse gases, the warmer the climate has been. ”
No. The warmer the climate has been the more CO2 and other greenhouse gases there have been in the atmosphere.
I have difficulty with the implication that it’s the gas that is making the temperature change.
We know that plants transpire one heck of a lot of water and self regulate their leaf temperature. This has been clearly measured. I could just as easily dream up a case where it was the trees cooling the place off and the O2 is just a side effect.
Or a scenario where the total convection of water vapor to altitude (from other drivers) disposed of a lot of excess heat, but also came down as extra rain, leading to more plant growth (both on land from the water and at sea from eroded nutrients.)
I don’t get it. Why is everyone so eager to leap off a cliff of conclusion about causality?
I would be much more willing to believe a paper that said, roughly, “We considered all the things that we thought might correlate and this is the list ranked by best supporting evidence. We like #2 best for these theoretical reasons, but #1 has more support in the data.”
For example, we’re all “wrapped around the axle” about CO2 warming the planet, yet what I’ve seen in GIStemp is that it has more to do with asphalt than with air. Yet only here do we hear folks say “maybe it’s the thermometer being over the asphalt.” Well maybe the O2 is just a side effect as well.
FWIW, Anthony, you really need to add an “Islands” thermometer validation project to http://www.surfacestations.org for the simple reason that in GIStemp, it can use a single bad surface station on an island to ‘warm’ the surrounding 20 degrees of latitude and longitude. Ellie pointed me at a couple of highly warming sites in the pacific. These two were Guam and the Marshall Islands. Guam, last I looked, was under the U.S.A. umbrella … so I think it rightly belongs in your audit of “U.S.A. Land Stations”.
Basically, in STEP3 of GIStemp when it pegs the (already molested) land data to grids and boxes, 2 island airports in the middle of the ocean can warm an area roughly the size of the entire continental U.S.A.; and it is pretty clear that the thermometers are often at major International Airports and Military bases. That has just got to have an impact…
http://chiefio.wordpress.com/2009/09/08/gistemp-islands-in-the-sun/#comment-854
Just a nitpick, the light-dependent part of photosynthesis, which lead to water photolysis, produces O2 and 2H+. Oxygen is simply a waste product that comes from water.
CO2 and the 2H+ from water photolysis are then used to make sugars in the light-independent part of photosynthesis, giving water as the waste product. So it’s somewhat misleading to say that CO2 is converted to oxygen.
The news release is puzzling because the paper abstract doesn’t say a thing about temperatures. Sounds like editorializing by the author and friends.
What if it’s not about warming or cooling at all?
I mean, CO2 fertilizes plants and creates lot’s of lush plant life. That lush plant life uses lot’s of CO2, and creates lot’s of O2. All that could happen independent of any “forcing” going on by the gases involved.
Now, if it just so happens that warming planet creates more CO2, and also increases water vapor which increases rainfall, then, as the planet does some cooling, we use up this CO2 and make O2, you have the same thing happen, but the linkages are different.
As always, correlation does not prove causation.
I know this isn’t directly towards the idea behind the article, but if burning carbon-based materials is an exothermic reaction (generates heat), then is photo synthesis endothermic (absorbs heat) and if so, where does that heat drawn from?
more natural forests
less pavement
keep it simple stupid
(no need for CO2 mythology)
Carl (19:12:01) :
I know this isn’t directly towards the idea behind the article, but if burning carbon-based materials is an exothermic reaction (generates heat), then is photo synthesis endothermic (absorbs heat) and if so, where does that heat drawn from?
Sunlight, more specifically blue and red/orange wavelengths.
“there is a historical correlation between oxygen and temperature fluctuations towards global cooling.”
Right. Scientists who can’t get into their thick skulls that correlation doesn’t mean causation. Superfantastic.
“This method is based on analysis of chrome isotopes – different chemical variants of the element chrome. It turned out that the chrome isotopes in the iron rich stones reflect the oxygen content of the atmosphere.”
What the hell is “the element chrome” that has “chrome isotopes”? I can’t find that one on my periodic table. It’s very difficult to take seriously a “science” article that can’t get the correct name of an element.
REPLY: It is a UCLA press release, and the element is Chromium which has the symbol Cr and atomic number 24. – Anthony
I too thought use of the term “chrome” rather than chromium detracted from the article and unfortunately it does reflect unfavourably on this blog. It might be a thought to highlight that sort of sloppy reporting and state that the source is not Anthony Watts but whatever it happens to be. I can see it could be quite difficult but if not it provides further ammunition for the crowd at open mind and realclimate who spend hours denigrating WUWT.
There is no way that the biosphere could have created all of that O2. The conversion of CO2 AND H2O into hydrocarbons and O2 is nice and simple chemistry, but look at the amount of atmospheric oxygen involved. The biosphere is almost steady state more or less. Most atmospheric oxygen is the result of solar disassociation of water into O2 that gravity holds and H2 that drifts off into space. Only a water planet can have an oxygen enriched atmosphere. A large and dirty ocean will limit CO2, no photosynthesis needed.
The biosphere is an added modifier, not the main cause. The very early Iron bands are before the existence of the biosphere.
Bill Illis (17:33:29) : There were at least two other periods of very high oxygen levels.
300 million years ago during the Carboniferous which contained an ice age, low CO2 and very high vegetation output (lots of coal and oil comes from this period). O2 may have been as high as 35% of the atmosphere and forest fires would have been unstoppable without lots of rain.
100 million years ago during the Cretaceous when O2 was as high as 30%, CO2 was relatively low and temperatures were likely the highest in Earth’s history that we know about (4C higher than the PaleoEocene Thermal Maximum). Lots of oil and coal comes from this period as well. Sea levels may have risen 250 metres above today and flooded 20% of the continents.
So I’m not sure this proposition really holds throughout the record.
Bill Illis is absolutely correct. The combination of high O2 concentrations and high temps in the Carboniferous and Cretaceous utterly deflate and disprove Frei’s theory. Further, the high O2 during those periods fueled massive fires, possibly continental conflagrations, the evidence of which is abundant fusain (fossil charcoal, ash, and other pyrolysis byproducts) found in coal.
The best reference for a complete and comprehensive examination of fusain is:
A. C. Scott. 2000. The Pre-Quaternary history of fire. Palaeogeography, Palaeoclimatology, Palaeoecology Volume 164, Issues 1-4, December 2000, Pages 281-329.
doi:10.1016/S0031-0182(00)00192-9
Dr. Andrew Scott of Royal Holloway, University of London, is one of the premier paleobotanists in the world. His work and that of his students is unsurpassed. Paleobotany is key to understanding paleo climates.
Perhaps they are confusing cause and effect….lower water temperatures means higher solubility of oxygen….doesn’t mean the temperature drop was caused by the oxygen….
In addition to defining a new element “chrome”, the press release throws in the comment “chrome isotopes – different chemical variants of the element chrome”
Oh dear, I hope the the people who actually did the work have a quiet word with their public relations dept.
I know that it is a press release, but the language interests me, it is designed to pander(Panda?) to the general audiences attraction to newness.
Examples……”using a completely new method”
“everybody talks”
“new analytical method”
“the method is a unique tool”
Certainly not a sober referred paper…..but wait!……
“To understand the future, we need to understand the past”
Now ya talkin’…..!
Note that the study does not state that O2 related to photosynthesis will induce a global cooling. Moreover, I would like to draw your attention to the fact that, in this case, the additional CO2 comes from the burning of fossil fuels which actually CONSUMES oxygen. There’s a high chance that the global balance is very close to zero, if not negative given that CO2 atmopsheric concentrations tend to increase.
The carbon sequestration people must be jumping of joy… they have the means to bury CO2 AND the oxygen used in the combustion process.
I also read once that molecular hydrogen is also a very potent global cooling gas… bye bye hydrogen fuel cells.
Mike D. (21:35:54) (and Bill Illis):
The Carboniferous was NOT a warm period. There was massive continental glaciation in Gondwana. The common idea that this was a warm interval is due to the huge coal deposits that accumulated in coastal swamps in tropical areas. However this was actually caused by glaciation too. The rapid shifts in sea-level caused by glacial/interglacial cycles kept flooding the equatorial lowlands causing the typical cyclical coal/shallow marine/coal/shallow marine structure of the coal measures.
Two points…
1. Correlation IS NOT Causation.
2. From comments, it looks like even the correlation isn’t very good.
Another cause/effect or effect/cause issue, which is unlikely to be resolvable using the Paleoclimatology methods available today.
For the last 100 years or so since atmospheric oxygen has been measured, levels have been at at 21% (within the error of the differing measuring techneques used over the period).
The perctage of total oxygen trapped within atmpospheric carbon dioxide is vanishingly small. If all of it was released it would not show up as a detectable signal on the O2 levels which are a nearly a hundred times bigger. In any case the process would be self regulating. As CO2 was converted into carbon and O2 the rate of photosynthesis would reduce, particularly if the increased O2 correlated with lower temperatures as well. So even if O2 was correlated with temperature, which seems very unlikely, linking this with CO2 is just nonsensical.
The Carboniferous was about 350 million years ago, the sun would have been notably weaker, perhaps more than 3%.
3% of 288K is 279K or an average of only 3C. What prevented a planet wide ice age?
What amount of oxygen are we talking about? I don’t think the atmosphere will increase its oxygen content up to 30% by the year 2012. If there is some increase, it would be in the parts per million range. Not significant if you compare to the actual 21% the atmosphere has nowadays. It seems to me very difficult to measure an increment in the part per million when the actual amount of oxygen in the atmosphere is 21%. I don’t think there is any quantitative correlation.
This reminds me too of the anthropogenic radiative forcings described at the IPCC AR4 where the anthropogenic ozone error bands cover from negative to positive values. In other words, they don’t know whether anthropogenic ozone variations cools or warms. Oh, they can also study how this minuscule increment of oxygen concentration may affect the concentration of ozone in upper atmosphere, and its cooling/warming effects.
Regarding the chrome thing, i googled ‘chrome’ and I had around 74,4 million results. They didn’t coin a new word. What webster has to say about chrome? two entries:
The use of chrome instead of chromium may have come from the Facultad de Ciencias in Uruguay. Cromo is Spanish for chromium. Anybody knows what is danish for chromium? Maybe it is actually chrome. The chemistry part of the press release needs a lot of polishing.
It is funny to see how etymology works in English, seems that all English words that comes from Greek and Latin have to pass through the French filter.
BTW, small typo. it is Geología. (it seems you tried to write an accent by switching to spanish or french keyboard but somehow it didn’t work, you wrote a dot-less lowercase i, I am trying to reproduce that but I can’t)
“Anybody knows what is danish for chromium? Maybe it is actually chrome. ”
“krom”, so yes chrome is almost certainly “danglish”. As a french acquaintance once said “the language of science is bad english”.
dorlomin:
Temperature is not linear with respect to insolation.
However what you mention is known as the “faint young sun paradox”.
It should have been much colder in the past, but there has been unfrozen oceans on Earth for at least 3,8 billion years and except for the two intervals mentioned in this thread (2,4-2,2 and 0,7-0,5 billion years ago) there are almost no traces of precambrian ice ages.
LS, DK
Chromium is “krom” in Danish.
LS
So if co2 increases as a percentage of the atmosphere, and oxygen increases as a percentage of the atmosphere, what decreases?
Or does the atmosphere get bigger??
Or what???
tty (03:14:57) :
However what you mention is known as the “faint young sun paradox”.
It should have been much colder in the past, but there has been unfrozen oceans on Earth for at least 3,8 billion years and except for the two intervals mentioned in this thread (2,4-2,2 and 0,7-0,5 billion years ago) there are almost no traces of precambrian ice ages.
And yet the sun warms as it ages. What kept the earth at a livable temperature in the past……
Chrome is English for the use of Chromium when used as electroplating for metal surfaces. I thought it was common usage but perhaps not.
Once again I think papers like this should be viewed as examples that what we don’t know about climate is vast.
PG 21:06
I could not disagree with you more.
Photosynthesis by the earliest forms of plant life during the Archean period began to produce significant amounts of oxygen. As oxygen began to be produced large amounts of iron which had accumulated in the early ocean were attacked by the accumulating oxygen. When oxygen (O2) reacts with iron (Fe) containing substances such as FeS2 (pyrite), iron ores are produced. Oxide rocks such as limonite, hematite, magnetite (a magnetic rock), and siderite are among the iron ores. Rocks such as these are mined today, and the iron (Fe) they contain is extracted.
Over a period of a billion years, huge deposits of iron ores were laid at the bottom of the sea. This activity took place between 3.5 and 2.5 billion years ago. Iron ores mined today in the United States, Australia, and South Africa, are part of the huge deposits laid down at that time. Once the oceans were swept clean of iron, then the oxygen could begin to accumulate in the atmosphere, and respiration by sophisticated life forms could begin in earnest. It took a billion years for this process to complete.
Thanks
William
The name Chromium comes, if I recall correctly, from the fact that many of the salts of Chromium are strongly coloured; ‘chroma’ being the Greek word for ‘colour’ I think. This is all dragged back from a not-often used part of my brain which was busy way back in the mists of time… I’ll see if I can find some examples.
oxygen is like co2- it lags not leads!
PG at 21:06 said: “The conversion of CO2 AND H2O into hydrocarbons and O2 is nice and simple chemistry, …”
If that chemistry were so simple, we would not be concerned with energy resources. We obviously have a handle on the combustion of hydrocarbons to CO2 and H2O products. If PG has a “nice and simple” means to convert CO2 and H2O back to methane and molecular oxygen, I certainly wish he’d let me in on the secret: I’d like to retire with a summer estate in Scotland and a winter villa in Tuscany.
These guys are hyperventilated, too much brain oxygenation. It is irrelevant if there was or if there is more oxygen or CO2, air heat capacity is too low compared with water. This is the same CO2/gw mantra, as seen from the other side.
“The more CO2 and other greenhouse gases, the warmer the climate has been.”
Well that’s not true is it? Late in the Ordovician for example, CO2 levels were around 5000 ppm, yet temperatures plummeted into a glacial epoch.
It’s a good thing that this study was done in part by the University of Copenhagen. The researchers won’t have to purchase carbon offsets for their travel to the upcoming “Sky Is Falling” conference.
The geologic record suggests that increasing earth temperature eventually leads to increasing atmospheric CO2. We also know that CO2 is less soluble in warmer water; which leads to the assertion that the ocean is warming and hence giving off more CO2; yet other measured data says the ocean isn’t warming, so how can it be giving off CO2. Then others add, that the increasing CO2 is proof that the oceans are warming. What a mess.
Well the oceans CAN outgas CO2 without warming; so how could that work.
Here’s just a thought for your consideration.
1/ We know that the oceans have a temperature gradient, being warmer at the surface and cooler as you go deeper. (generally) My diving friends say that it cools at a certain rate down to some depth, and then the rate of decline drops, but it still cools as you go deeper; but at a much slower rate.
2/ We know CO2 is more soluble in colder; and hence deeper waters, and also that Henry’s Law sets the equilibrium level of dissolved CO2 versus atmospheric CO2 partial pressure; and yes I know that the CO2 in the ocean chemistry is more complex than just a dissolved gas; but it is still more soluble in colder water.
3/ The fact that CO2 is more soluble in colder water means that there is a constant diffusion; a temperature gradient driving of CO2 from warmer surface waters to deeper colder waters; which thus tends to deplete the warmer surface waters, enabling additional CO2 passing from the atmosphere into the surface waters.
4/ As a result of this constant depletion of the warmer surface waters by the temperature gradient driven diffusion, the surface waters never reach their equilibrium level of dissolved CO2, as set by Henry’s law. This is one of the mechanisms by which excess CO2 is constantly being removed from the atmosphere.
5/ If the ocean surface temperatures suddenly increase, due to El Ninos or ENSOS or whatever, this does not mean that there will be a sudden rush of CO2 back into the atmopshere from those warmer surface waters; they are already below the Henry’s law equilibrium concentration and can remain below it even with a small temperature increase. The problem is the surface waters are depleted by the pumping action of the temperature gradient.
6/ In order to get more CO2 out of the warmer ocean surface into the atmosphere, you need some turnover of the ocean waters, to bring some of that colder CO2 enriched water back to the surface, where it can mix with the surface waters, and raise the surface concentration of CO2 back to where the surface is now in CO2 excess versus Henry’s Law; and then the oceans can outgas more CO2.
Now I realize their are all kinds of rate situations to these processes, and all you chemists out there know more about that than I do; so I’ll let you work on the details; but as you can see, it is possible for the oceans to give up more CO2 to the atmosphere, without noticeably warming; but it takes a mixing that overcomes the former depleted surface condition by bringing stored CO2 up from colder waters (with the water by convection; not by diffusion).
Also the biological processes that take place in those nutrient laden cooler waters result in the food chain storage of CO2 in skeletons of defunct critters which falls to the bottom to make carbonate rocks.
So no; CO2 emission from the oceans is not (necessarily) proof of warming oceans.
George
“”” Jimmy Haigh (06:49:38) :
The name Chromium comes, if I recall correctly, from the fact that many of the salts of Chromium are strongly coloured; ‘chroma’ being the Greek word for ‘colour’ I think. This is all dragged back from a not-often used part of my brain which was busy way back in the mists of time… I’ll see if I can find some examples. “””
Don’t know if your Chromium = color story is true or not Jimmy; but it works for me. So here’s some examples.
Aluminium Oxide, Al2O3 in single crystal form is quite colorless; and we call it “Sapphire”. Gem sapphires can come in all colors of the rainbow, due to the inclusion of impurities into the crystal; but most people think of sapphires as being blue. They can be yellow, green and even red; well the red ones are more of a pink.
But of course there are true deep red sapphires, and the most common cause of that deep red color is that the doping impurity in the sapphire is Chromium; and by definition, red sapphires that are red due to chromium doping are called Rubies (but there are red sapphires that are not rubies).
The State mineral of Colorado is a cubic crystal called Rhodochrosite. These crystals are spectacular brilliant red and clear as a bell (free of inclusions). The chromium ion turns up in lots of situations in that brilliant red color; Cerise might be a more accurate description of the hue.
I’m not sure whether that is the Cr+2 or the Cr+3 ion, but it is one of those two; there is also a cr+6, dunno how rare that is.
And of course the original Ruby laser was made from a synthetic Chromium doped sapphire (Ruby) and emitted a red laser line.
So I’ll take your Greek story as gospel Jimmie.
“”” Carl (19:12:01) :
I know this isn’t directly towards the idea behind the article, but if burning carbon-based materials is an exothermic reaction (generates heat), then is photo synthesis endothermic (absorbs heat) and if so, where does that heat drawn from? “””
Well one thing that photosynthesis is not, is “endothermic”. You can take plant leaves and heat them all you like and they will not absorb CO2 and emit oxygen; but if you get them hot enough they will do the opposite, and absorb Oxygen and emit CO2 along with ashes.
But if you really wated to know where does the ENERGY come from in photosynthesis, then that comes from the sun; and it does result in cooling because instead of that solar energy being converted to waste “heat” it is converted to plant materials along with CO2 remocal and O2 emission.
But it is wrong to call the reaction “endothermic”; nothing cools down as a result of photosynthesis; but it may heat up less, than if photosynthesis doesn’t take place.
George
“”” Phil. (20:17:26) :
Carl (19:12:01) :
I know this isn’t directly towards the idea behind the article, but if burning carbon-based materials is an exothermic reaction (generates heat), then is photo synthesis endothermic (absorbs heat) and if so, where does that heat drawn from?
Sunlight, more specifically blue and red/orange wavelengths. “””
Norty norty ! see my comment to Carl above.
Also it is well known that Chlorophyl containing plant materials strongly reflect the near IR say in the 700-900 nm range and register as reds on Infra-Red film which is not too responsive to wavelenghts much longer.
So is it true that orange/reds which would be 600-700 nm actually take part in Photosynthesis, rather than the higher energy photons; that is only about 2 eV photon energy ?
George
George,
A reaction’s endo- or exo-thermicity is defined by the change in the state function known as enthalpy (delta H) which, under constant pressure constraints is also what is called “heat of reaction” or q_p. If the products of a reaction have a higher enthalpy than the reactants, then the reaction is by definition endothermic. Since enthalpy is a state function, or, if you prefer, an exact differential, it is path or process independent: changes in enthalpy depend only on initial and final state (reactants and products if the process is a chemical reaction). Thus, it matters not whether the energy input to the reactants takes place via absorption of a photon; via thermal excitation; via ultrasonic techniques or by one step or twenty: the overall process is still “endothermic.”
Gary (18:42:12) :
The news release is puzzling because the paper abstract doesn’t say a thing about temperatures. Sounds like editorializing by the author and friends.
I was puzzled, too. You are correct, there is a huge disconnect between the press release and the abstract. The title of the press release “More Qxygen – Colder Climate”, is grossly misleading. As you note, the abstract does not say a thing about global warming, global cooling or CO2. The actual study probably does not either, but I’m not going to spend $32 to find out. The author is a geochemist who specializes in isotope dating. His curriculum vitae is most impressive, but it shows no experience in climatology. (See: http://geo.ku.dk/english/staff/cv/?personid=111368). I would take his editorial comments on global warming with a grain of salt…
If the purpose of the press release was to seek publicity, it achieved it’s goal. After all, it was posted on WUWT.
“”” Aelric (11:34:25) :
George,
A reaction’s endo- or exo-thermicity is defined by the change in the state function known as enthalpy (delta H) which, under constant pressure constraints is also what is called “heat of reaction” or q_p. If the products of a reaction have a higher enthalpy than the reactants, then the reaction is by definition endothermic. Since enthalpy is a state function, or, if you prefer, an exact differential, it is path or process independent: changes in enthalpy depend only on initial and final state (reactants and products if the process is a chemical reaction). Thus, it matters not whether the energy input to the reactants takes place via absorption of a photon; via thermal excitation; via ultrasonic techniques or by one step or twenty: the overall process is still “endothermic.” “””
Well Aelric, one thing I am not is a chemist. I’m not sure I completely grasp all of your explanation; perhaps I should say I am sure I did not grasp all of your explanations, since it seems you are saying if there is more energy input than output, it is endothemic, and if the energy output exceeds the energy input then it is exothermic.
For example in one sense one would think that photosynthesis is a 100% efficient process; a photon is absorbed and some reaction takes place and all of the photon energy is taken up by that process, with no waste energy left over. I’m sure that is only true if the photon is of the exact energy required to complete the reaction. Presumably if the photon energy is higher than required, then there must be some excess energy which will manifest itself in the form of heat; assuming it isn’t emitted as a lower energy photon.
Well I guess I will have to hit the books to get to where your explanation makes sense to me.
Thanks for the lesson; nothing goes to waste here.
George
Not quite. Energy outputs cannot exceed inputs, or vice versa. Enthalpy is not about total energy, only direction of heat flow.
Exothermic – Reaction in which a system RELEASES
heat to its surroundings.
Endothermic – Reaction in which a system ABSORBS
heat from its surroundings.
George E Smith.
This is best understood in the terms of Hess’s Law, plenty of good explanations on the web.
Kindest Regards
So OK I got the gist of Hess’s Law, and don’t have any problem with that concept; nor do I see it as relevent to the reaction being considered; i.e. photosynthesis.
My understanding was (silly me) that an Exothermic reaction would release “heat” energy (and therefore result in a temperature increase of the system) while an Endothermic reaction would absorb heat and thereby result in a reduction of the system temperature. Now I can see there are some problems.
For example, If I pass a current of 0.5 Amps through a 4 Ohm resistor, it takes 2 Volts across the resistor, and heat is generated at a rate of one Watt.
If I apply the same 0.5 Amp to a high efficiency LED at the same terminal voltage of 2 Volts, I am still consuming electricity at the same one Watt rate, but my LED may only be generating “heat” at one half a Watt rate, so it will get less hot than the resistor did; the remaining half Watt is emitted in the form of Light (em radiation).
Now of course ultimately that light is going to be absorbed into something, perhaps very remote, and will then likely be converted to heat at some remote location. So although my expectation is that the same total amount of “heat” will ultimately be produced my LED will still run cooler than the resistor.
But now what if that light beam is collected, and focussed on to an appropriate photo-diode, and reconverted to an electric current. Well you see this can go on for ever, and I can see that Hess’s law will apply no matter how complex the set of reactions.
But what happens to the sunlight that is absorbed by tree leaves and eventually converted along with CO2 into wood. It seems to me that that should not result in local heating.
A Stanford/Livermore Labs team claimed that it would result in local heating, whereas the snow that would be there, absent the trees, would reflect the sun, so in their view the trees would cause global warming, if they are grown in otherwise snowy regions.
In fact Dr Steve Running at Montana State (I think) called those authors on it, and basically scotched the idea; well I am sure they all got grant money out of the deal.
George
But for me, I would still like to see an endothermic reaction cool things down; like a refrigerator for example.
“But for me, I would still like to see an endothermic reaction cool things down; like a refrigerator for example.”
The reaction of barium hydroxide octahydrate (aq) with ammonium nitrate (aq) is a classic general chemistry experiment of this type. With the reactant solutions close enough to the freezing point the product solution will solidify. But don’t eat the barium containing ice cube!
Beverage chillers essentially do what you suggest. So, use this as an excuse to go enjoy “a cold one.” 🙂
Missing in virtually all astronomical and climatological studies is Planet Earth’s geophysical, plate-tectonic context. The analogy with Alfred Wegener is quite precise: Before deep-ocean (“bathymetric”) probes discovered otherwise, geologists assumed that continental landmasses differed little from “abyssal plains,” invalidating Wegener’s “continental drift” hypothesis because no geophysical mechanism could drive, for example, Africa and South America apart. Yet any child can see the two fit together beyond coincidence. Only in 1964 did science realize that features such as the Mid-Atlantic Ridge bore no resemblance whatsoever to the continents– that “sea-floor spreading” via upwelling magma and subduction zones made nonsense of any “static Earth” scenario.
A comparable revelation of near-equal import occurred about 2002, when geologists discovered that since the mid-19th Century vast, worldwide subsurface volcanism –“magmatic episodes”– has consistently affected global ocean basins. Even one fifty-thousandth of Earth’s 4,000-mile radius equals some 400 feet… “as if the Earth in fast, thick pants were breathing” [“fast” meaning centuries, if not millennia]. Earth alternately expands – contracts, pulsing in rhythms determining long-term climatic effects.
As warmer water rises to shallow continental shelves, accelerating evaporation –an “air conditioning” (cooling) process– drives hot air higher, drawing cold-air currents underneath. The result is flooding rains in summer, blizzard snows in winter… but even this widespread effect is marginal unless continental dispositions interfere with global atmospheric circulation.
For tens of millions of years now, North and South American continents have effectively walled off Eastern from Western Hemispheres; at one pole sits the Arctic Ocean, the other holds Antarctica. Over Earth’s current 1.8-million year Pleistocene Era, ice ages averaging 102,000 years interspersed with median 12,250-year interglacial epochs have occurred regular-as-clockwork.
Paleontological evidence puts a definitive end to continental ice-sheets about BC 8800 –10,800 years-before-present (YBP)– but a 1,500-year “cold shock” called the Younger Dryas reset the interglacial clock to 12,300 YBP. (Astronomers have known since 2006 that this extreme rebound stemmed from a swarm of cometary and meteorite debris spraying to the inner solar system when an extra-solar body disrupted Sol’s encompassing shell called the Oort Cloud.) On this basis, Earth’s current Holocene Interglacial Epoch was loosely due to end as of AD 2000 + (12,250 – 12,300) = AD 1950. Given a looming Dalton if not Maunder Minimum, Ice Time may be nigh upon us.
Since Earth’s “Cretaceous/Tertiary (K/T) Boundary” 65-million YBP, geological eras have averaged about 12-million years. This means the Pleistocene’s well-defined cyclical ice ages could persist at least another 10-million years, that is, until plate tectonics redistributes continental landmasses sufficiently to restore
benign global atmospheric circulation-patterns.
Neither botany nor climatology are empirical disciplines, formulating testable hypotheses, designing falsifiable experiments amenable to peer-group replication. In 1960, Edward Lorentz definitively showed that “sensitive dependence on initial conditions” aka Chaos Theory renders complex systems necessarily “non-random but indeterminate”– however detailed and sophisticated, computerized “climate models” are by mathematical definition incapable of making meaningful projections. Chaos Theory of course shades into Benoit Mandelbrot’s “fractal geometry,” self-similar on every scale, not to mention “Information Theory” as developed by Kurt Godel and Claude Shannon among others. Regardless of data inputs, the very notion of extrapolating putative climate-trends is nonsense on its face.
Gore, Hanson, Mann et al. aren’t right– they aren’t even wrong. Climate Cultists are no more scientists than are creationists, mystics, psychics of every stripe. Best consider such hubristic arrogance the work of Luddite sociopaths akin to Ehrlich, Holdren, Singer– terminal misanthropes celebrating human megadeaths in terms of “population bombs,” mass epidemics, resource depletion, you name it. Norman Borlaug of Green Revolution fame is Holdren’s particular bete noir– humanity is (and we quote) “a seething mass of maggots” better off exorcised, exterminated. Holdren’s subtext is an atavistic, virtually nihilist appeal to Lebensraum.
How long, O Lord, how long?
were slowly pulsating, lava wells up from oceanic rims.
George E Smith
Gosh I am a little taken aback, less by you, than Stanford- Livermore.
Golly gosh. Bear with me.
Yes your electronic example is perfectly correct.
And yes If I burn a hydrocarbon so it decomposes into H2O and CO2 the reaction is exothermic so heat is released to the universe.
To reverse this and turn C02 and H2O into some complex hydrocarbon by whatever exact route means I must supply energy, for instance sunlight, and you can describe the reaction as endothermic because it needs outside energy to cause it to happen.
Although strictly chemists use the term endothermic to describe reactions which adsorb the energy needed as heat rather than some other source of energy.
No matter.
Now all such processes, in this universe at least, are subject to the second law of thermodynamics, the Arrow of Time, which means they are irreversible.
For instance chemical reactions are reversible, X plus Y goes to XY and vice versa depending only on the change in energy between the separate states of X and Y and the compound XY.
Whih is why chemists write their equations with a reversible equals sign which my keyboard doesn’t seem able to do, to show that given the initial conditions the reaction will go one way or the other.
But even if you did the reaction X plus Y to produce XY and then reversed it to decompose XY back into X and Y there are losses in the process so overall some energy is lost as heat and cannot be recovered: and the entropy of the universe increases.
I hope I am making sense here, and not being condescending either, but if you are either puzzled or annoyed please say so: and I will try again.
Now as to trees as sunlight falls upon them overall they convert CO2 into complex chemicals that amongst other things make wood. In terms of energy the process is far from perfect so some energy must be released as heat.
So what? The tree and its leaves are not a perfect adsorber of sunlight, so some may be scattered and adsorbed by other trees or the earth and some reflected upwards.
Obviously if the sunlight falls upon virgin snow which, for the sake of argument, reflects it all perfectly, then the trees by comparison have indeed adsorbed solar energy.
Again so what? If the sunlight fell upon black earth it would have adsorbed all its energy. And in warming radiated some of it backto space but being colder than the trees less than they do.
So quite what the Stanford Livermore people are saying beyond the obvious I do not understand.
That an Earth covered with snow and ice would adsorb less energy from sunlight than one where the land has vegetation?
Amazing give the lad a PHD and a grant at once.
By the way I would be wary of referring to refrigeration processes as being endothermic, there are a few, such as sachets with a clip you can buy, but for all practical purposes natural and mechanical ones are not.
Hope this helps.
Kindest Regards.
Flanagan; re consuming oxygen and producing oxygen from CO2. You are partly correct there is a balance in burning fossil fuels; Coal – about 6 Btpy but there is also 45 Mtpy limestone used in flue gas desulphurization, 2.5 Btpy of limestone burned in making cement and lime, 100 Btpy as a flux in making steel (150kg/ton of steel), plus other metallurgical use for base metals….. I judge you to be a smart guy but perhaps more like a smart teenager who is skilled in apriori reasoning because he doesn’t have experience. It would be nice if you took off your collegiate debating cap and provided us with more quantitative data.
John Blake (19:55:11) : ” Missing in virtually all astronomical and climatological studies …
Thank you, John.
Gary Pearse (21:10:45) : “… there is a balance in burning fossil fuels; Coal – about 6 Btpy …
Can you assist me here, Gary? I have read of a very basic “X ounces of coal can drive a steam locomotive Y miles” ratio and would like that information in some form (and not only for my children and grandchildren…).
Gary: yes, limestone gets oxidized in these processes (I guess, because you seemingly don’t care about giving details). How exactly is thus supposed to INCREASE the atmospheric content of O2?
Btw, I’m not a “teenager”. Are you?
Flanagan is right: this is _not_ an example of a “self-regulating effect on climate” because the excess CO2 that leads to increased plant growth (and O2 emissions) mostly comes from C+O2 from combustion processes. So as long as CO2 concentrations are going up, O2 concentrations are likely to be going down. And, because people here like observations, a decrease in atmospheric O2 has indeed been observed: see the biogeochemistry chapter of the IPCC 4th assessment report, or use google.
this message re coal for locomotives was for
Roger Carr (23:14:08) :
http://hypertextbook.com/facts/2006/LunChen.shtml
An average value for the thermal energy of coal is approximately 6150 kilowatt-hour (kWh)/ton.” (8,240 horsepower-hours). You would have to have values for the traction load being hauled, the speed of the train and an efficiency factor for the steam engine (the larger the more efficient). My father was a firemen on the Canadian National as a young man and with 100 cars loaded – approx 10,000sht ton gross wt, he shoveled 20t per rail division of about 125 miles – roughly 6 miles per ton of coal. We used to laugh at the miner’s song “Sixteen Tons” – hey loading 16t was considered wussy’s work by locomotive firemen.
Flanagan,
Apologies for teenager remark. (I had 6 of them in that age group at one time and I remember the exasperating nature of bright children’s argument style – with fondness I might add). I don’t dare argue with them now – especially one of them who is a post doc physicist starting at JPL in October, having completed a post doc at Scripps. She now can be exasperating because she’s kind to me in arguments.
The limestone is not oxidized but rather CO2 is driven off. My point was that there is lots of extra Anthropo CO2 that could feed plants to generate extra oxygen. Wouldn’t it be nice if we could resolve the whole issue by greening up the planet a bit more.
Gary Pearse (10:49:08) : “An average value for the thermal energy of coal …
Many thanks, Gary.
@John Blake (19:55:11) :
Hear! Hear! You called it pretty much the way I see it. We’ll get real climate change when the continents make a major shift in position. Meanwhile, on geologic time scales, the glacials and interglacials are just “weather.”
I wonder; how would climate change if the Isthmus of Panama disappeared?
“”” a jones (20:29:30) :
George E Smith
Gosh I am a little taken aback, less by you, than Stanford- Livermore. “””
No problemo a, I understand all of that; but can’t say I always have it at my fingertips.
For me, Chemistry stopped my last year in high school; just when things were starting to get treally interesting; so consider my self to be very weak on Chem, specially Organic; but I have no problerm with the general idea expressed in Hess’s Law. I have always held that adding oxygen to a gasoline fuel as we are mandated to do in California; by adding either an alcohol (ethanol) or previously an ether (MTBE), is tantamount to adding water to the gasoline, from the point of view oif the avaiable energy of combustion. My car has an engine, whose function is to add oxygen to the gasoline to release energy, so why would I want them to release that energy in the additive factory.
I’m happy with the notion that an exothermic reaction adds heat to its surroundings, while an endothermic reaction extracts heat from its surroundings. I guess it depends on the question of isolated versus closed, versus open systems. Also agree that refrigerators was not a great analogy.
In any case my basic point was that the boreal forests absorb solar energy (and CO2) and grow wood; and that is far more enviromentally useful that simply having some snow reflect what very little sunlight reaches those places anyway. There’s a reason that it is cold there; and also conifer forests are like optical anechoic chambers, and very efficient at trapping sunlight, in order to survive in those latitudes.
I actually contacted Prof Running about his public comments re the Stanford/Livermore snafu.
George