Acidic Ocean

[MCsaxmaster]

I said it above, but I really think the point is worth making again, and stressing:

Climate change and ocean acidification are two DIFFERENT phenomenon.

It is logistically feasible to have one without the other. However, since atmospheric CO2 affects both climate and oceanic pH the two can co-occur as well.

Just a quick comment on one point made above, and one I see made here and there. The comment is related essentially 'how do we know that atmospheric CO2 is increasing due to human activities and not due to natural processes?'

The question is perfectly reasonable in and of itself, but IME it is often asked not by those truely interested in the answer, but simply as a diversion meant to cast a general sentiment of doubt on climate change, ocean acidification, etc.

The answer, however, is quite simple. We know pretty precisely how much CO2 we're releasing to the atmosphere by burning fossil fuels, cement manufacture, and deforestation. The quantity of CO2 in the atmosphere, however, has only increased by half as much as what we would see if everything we were emitting stayed there. As Mike says above, these sources of CO2 and other naturally occuring sources have different istopic signatures--not quite as good as a fingerprint, but pretty close. As such, we can (and have for decades) measure changes in the isotopic composition of plants, marine carbonates, etc. to determine where the "missing" half of our CO2 has gone. Most of the half that isn't in the atmosphere has gone into the ocean. A small portion of it has gotten sucked up by vegetation on land. Over the last decade or so, however, the ocean has been sucking up CO2 at a slowing rate, which is expected for several reasons (including well understood chemical effects, e.g., see Revelle factor).

Given what we do know about how C moves around the biosphere, it is utterly silly to suggest that atmospheric CO2 is increasing due to increased production from natural sources: we would be able to measure that in the isotopic data, and that is diametrically opposite of what those data show. Instead we know where the CO2 is coming from and why the atmospheric concentration is increasing: burning fossil fuels, cement manufacture and deforestation have left their isotopic fingerprint all over. The increase in atmospheric CO2 is also only HALF the quantity of CO2 released.

So, are human activities responsible for the increase in atmospheric CO2? No, they're responsible for DOUBLE the increase in atmospheric CO2. The ocean and terrestrial biomes have sucked up half of that CO2 for us, though that service is slowing.

For anyone that is honestly curious about how we know what we know, I hope that the above helps to make it a bit clearer.

Chris

 

[greenbean36191]

As for solar activity's impacts on warming and cooling cycles, EVERY major global climate model includes this factor. The sun is dismissed as the source of the recent trend though because the variation in output is orders of magnitude too small to account for it, even taking into account the uncertainty in the measurements.

I forgot to mention as well that the pattern of warming is inconsistent with warming due to changes in solar input. What we see is that the lower portions of the atmosphere are warming while the stratosphere cools. That is consistent with warming due to greenhouse gases, but inconsistent with warming from solar variation. In that case the whole depth of the atmosphere should be warming.

 

[Beaun]

I guess a current question that has yet to be answered is how much CO2 can the ocean absorb/handle, and what happens when it is unable to take any more, when is it at the saturation point?

We know how much is going in currently and the ocean has been a carbon sink for a long time, but what happens if it is unable to be a carbon sink? This all goes along with the idea of modles not being perfect. While they do great modeling with some very powerful computers, they are only as good as the information that is input into them, there is a lot we dont know about these very complex systems.

I also think the entire safer SUV idea is very interesting. People buy SUV's because they want to feel safe, while they are endangering other smaller vehicles on the road. It's off topic, but an interesting discussion none the less.

 

[power boat jim]

<a href=showthread.php?s=&postid=14679960#post14679960 target=_blank>Originally posted</a> by Beaun
I guess a current question that has yet to be answered is how much CO2 can the ocean absorb/handle, and what happens when it is unable to take any more, when is it at the saturation point?

I also think the entire safer SUV idea is very interesting. People buy SUV's because they want to feel safe, while they are endangering other smaller vehicles on the road. It's off topic, but an interesting discussion none the less.

Good question, I hope our Marine Biologists can shed a bit of light on this.

In regards to the other part of the "dual topic" in this thread, I Know some people have suv's in order to feel safe, but if you rember in the 1970's you could take the kids,dog and two weeks of luggage and toss all of it in the Bonneville and go. Whats more if you wanted to take the camper or boat with you it was no problem. Those old cars would do it and not lose a step.

Thats the reason I own an Avalanch it is for the utility part not the safety part.The family car of the 70's has been replaced by the suv. Though those cars were largly legislated out of existance by milage regulations, their purpose was not. Suv's were immune to the CAFE laws early on and were a refuge to people who still needed a way to continue to do what Americans have done since the 50's.

Now there is pressure to get rid of suv's but no one has yet to come up with a vehicle that can replace what a 1971 full size car could do, let alone todays suv.

The only way to get rid of the demand for suvs is to get rid of the need to go on family vacations, tow a boat or never have a need to move anything bigger then a suitcase.

 

[MCsaxmaster]

There is a saying (I'm not sure who coined it): no model is perfect, but some are useful.

Something to keep in mind is that every time we forecast future events--whether we are judging how to catch a fly ball, the influence of smoking on lung health, or the progression of spring to summer to fall to winter and so on--we are relying on a model, either implicitly or explicitly.

Simply put, it is impossible to predict ANY event without a model of some sort. The important question is not do we use models to get an idea of future events, the question is how accurately our models come to predicting specific, well-defined phenomenon. Any model can be perfectly useful for one task, and useless for another. Newtonian mechanics don’t tell us how to bake an apple pie, nor will a cook book help with airbag design. Hence, our tests have to be clearly defined.

We can confidently say that a dropped object will accelerate toward the Earth (in a vaccum) at 9.8 m/s2. We aren't even close to understanding everything about how gravity works. At a very fundamental level gravity is still deeply mysterious. However, we know enough about gravity that I can confidently predict what would happen to me if I were to walk off a tall building... Newtonian mechanics is very useful in an application where it can be used.

We understand enough about climate to provide extremely useful forecasts. The models certainly can and will be improved significantly in coming years, but what we have now (and in fact, what we've had for 20 yrs) does a pretty remarkably good job.

One quick example: Mt. Pinatubo erupted in 1991, causing temporary global cooling of ~0.5 C (for several months). Not only did the models at the time correctly predict cooling from the event, they were correct on the magnitude to within 0.1 C. That's pretty darn good. They're better nowadays. Yes they can and will be improved, but to pretend that they aren't already doing a pretty spectacular job of predicting the trajectory of the climate is silly at best, and dishonest at worst.

They're not perfect, but they are useful.

And again, climate change and ocean acidification are DIFFERENT phenomenon.

Now as for the ocean losing the ability to sink carbon: the ocean will continue to be a carbon sink as long as we don’t destabilize a bunch of methane hydrates, or something like that. As long as we don’t get into wicked positive feedback territory (in which case the ensuing climate change and ocean acidification will be worse than what we are likely to cause, and out of our control) then the ocean will continue to be a sink for CO2 emissions.

The SIZE of the oceanic sink, however, has been decreasing in recent decades, likely due to well understood chemical effects (buffer intensity, Revelle factor). The ocean will continue to suck up CO2 as we emit it, but it will not continue to suck up the PROPORTION of our CO2 emissions it currently is (or was a few decades ago) indefinitely. For instance, over the last 200 yrs ~48% of our emissions have been sunk by the ocean (reducing oceanic pH ~0.1 units). Today only around 1/3 of our emissions are being taken up by the ocean. Throughout the future the ocean will continue to take up CO2 from our emissions, though that capacity will diminish a bit over time, as oceanic pH drops (due to reduced buffer intensity).

Again, all of this is well understood, easily measured in the laboratory, fairly easily measured in the field, and well modeled. These sorts of relationships are highly certain, and when I say highly certain I mean like I would fall and go splat if I walked off a tall building is highly certain

Chris

 

[wld1783]

<a href=showthread.php?s=&postid=14679301#post14679301 target=_blank>Originally posted</a> by greenbean36191
I forgot to mention as well that the pattern of warming is inconsistent with warming due to changes in solar input. What we see is that the lower portions of the atmosphere are warming while the stratosphere cools. That is consistent with warming due to greenhouse gases, but inconsistent with warming from solar variation. In that case the whole depth of the atmosphere should be warming.

As far as solar changes I was referring to the ionization of the upper atmosphere which effects cloud formation...Cloudy days are cooler days. Cloudy decades are cooler decades.

Thanks for your detailed response. I’ve read arguments and talking points on both sides and still feel that the models are not reliable. Take into account this winter. Also don't forget about the profit being made with carbon credits. I'm not a conspiracy nut but follow the money. I also cannot buy that seismographs can give an accurate representation of the amount of gas each eruption releases.

As far as CO2 in the ocean, I dump a lot of CO2 into my reef via a calcium reactor and my ph is between 8.1 and 8.3. Algae and bacteria are wonderful buffers along with aragonite. My reef continues to grow under said conditions. I'm sure it’s the same for the ocean. I think temperature would have more of an impact in the way it affects certain enzymes within coral tissue and how certain pathogens thrive in a warmer environment.

As far as reefs I'm under the belief that costal development and over fishing impact the reefs in the most significant manner.

Just out of curiosity I wonder what the CO2 levels and average temperature were when the Cretaceous Great Barrier Reef formed. Not sure but I think O2 levels were significantly higher.


Bill

 

[geno7]

Man, I don't have the education level to argue your points and I find them all interesting. Now this brings me to my question. In 1 or 2 million years or maybe 2 billion the sun is going to run out of fuel. What are we to do? Makes it seem kind of point less doesn't it?

 

[wld1783]

<a href=showthread.php?s=&postid=14685618#post14685618 target=_blank>Originally posted</a> by geno7
Man, I don't have the education level to argue your points and I find them all interesting. Now this brings me to my question. In 1 or 2 million years or maybe 2 billion the sun is going to run out of fuel. What are we to do? Makes it seem kind of point less doesn't it?

If I live that long I plan on trying Ice Fishing. I hear it's an excuse to get out of the house. BTW Ice was pretty thick this year.

Bill

 

[MayorOfWhoVille]

First off, thanks guys for an interesting read. It's nice to see that some people are thinking about this problem that are actually interested in the nitty-gritty. I do notice that there are a few factors that have not been accounted for, or have been but only barely. Any feedback by people in the know or opinions about any of the following is certainly appreciated. Sorry for the rant, but...

First, I wonder if anyone making these models are accounting Henry's Law: at a constant temperature, the amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid (I assume this is accounted for). Basically, more CO2 in the air means more CO2 in the water. Another factor possibly being overlooked is the fact that the CO2 solubility in water decreases with a rise in temperature. So even as we pump more CO2 into the air and the poor ocean does it's best to follow Henry's Law at constant Temp, the world and ocean warm and the ability of the ocean to dissolve CO2 is decreased (the concentration of CO2 in the ocean still goes up, but not in a linear fashion with partial pressure). I also wonder how one accounts for the non-ideal aspect of this situation, namely the fact that the CO2 reacts with the solvent to produce H2CO3, an equilibrium that is also affected by temperature. Maybe these effects are too small to be of importance? I suppose the actual increase in temperature is fairly small and probably negligible, but hey, this is a planet's worth of ocean we are talking about here: is even a small effect really negligible?

Second, there seems to be a general consensus that the fluctuation of the suns' radiation is not and will not be a major factor in global warming. Assuming that the trends in the data collected from roughly 40 years of monitoring the sun from space and roughly 200 years of earthly observation of sun spots holds true for the foreseeable future, this may well be the case. However, I sincerely doubt that the sun only functions on this ~11 year cycle. I suppose we have enough to worry about without the sun increasing or decreasing its activity level over a period of more than a couple of hundred years. I only bring this up because of an article I read awhile ago talking about the flareups of other stars of similar solar mass and composition, suggesting that the seemingly docile nature of our star is an illusion based on the brevity of reliable observation.

Third, I seem to notice a trend in the reports coming from committees and scientists concerned with global warming. The trend is for the models and data to suggest mild to moderate warming over the course of the next century or so, until the next report comes out which suggests mild to moderate warming in the next fifty years, until the next report comes out suggesting mild to moderate warming over the next 20 years. This is a disturbing trend. The predicted rate of glacial and ice sheet melting seems to follow this trend as well. In short it seems that the more we look into the problem the more it looks like we are totally screwed over in a shorter and shorter interval. One of the most comical aspects of these reports seems to be the insistence of the scientists that they base their calculations on the current level of human related CO2 production (which they assume will remain constant over the relevant time frame). Have the scientists not seen the projected curves of CO2 production? The ones that have the rate increasing at an increasing rate? It really seems like they are only using the most optimistic approach possible for their modeling, like maybe if humans were extinct tomorrow then the warming will only be mild over the next 20 years. Maybe these scientists have never heard of China, or any of the other developing nations. Or maybe they think that American companies care about global warming and will enact some major initiative to hold or reduce the current levels of CO2 production. What a joke. It could be that they are still afraid of losing funding if they blow the whistle (thanks for that Bush). I would like to see a projection of global warming based upon the projection of CO2 production. Maybe they are counting on some unforeseen technology that will magically solve the problem of global warming. Like this guy from the University of Michigan that seems to think that we can solve the CO2 aspect of global warming by pumping CO2 into the deep ocean where it will dissolve...ummmm, is this guy a retard?

http://blogs.zdnet.com/emergingtech/?p=68

Is he single-handedly trying to kill the ocean? Because we all know that the deep ocean is totally unconnected to the surface and the ocean is totally unaffected by huge increases in the amount of dissolved CO2. Not to be pessimistic or anything, but I really doubt all of the flowery predictions where everything gets to go on as usual with no ill effects until those in charge (of policy) are all dead. That just seems too convenient. Maybe I'm just skeptical of the established hierarchy that got us into this problem in the first place (along with pollution in general and maybe even the economic collapse, but that is reaching a little...or is it).

Maybe we should just have faith in the George Bushes of the world (after all, they have been doing a great job so far) and assume global warming is a farce perpetrated by the liberal tree-hugging hippie scientists and all of their 'data'. Silly scientists, when will they learn that God will save us from our folly? While we are at it, we should totally put lead back in gasoline and finish cutting down the rain forest - useless bunch of trees.

 

[Poorcollegereef]

Well, water vapor (from my memory of a guest lecture for a NOAA modeler that receive part the the Nobel that Gore... marketed...uggg. in any case,) is actually a greenhouse gas that has as much if not more impact on climate (as wld began to allude to), but it traps heat. The difference with CO2 is that the "water cycle lifespan" (not using over technical terms) is short lived... hours, days, sometime weeks. CO2 on the other hand cycles over hundreds of years. This is the problem with CO2 sinks and natural remediation. We pump CO2 out in a much faster rate than it can be absorbed (as MCsaxmaster has elegantly put it). Even with high vegetation absorption, it takes an extremely long time for CO2 to be remove from the atmosphere.

As for vehicle choice. It is all about paradigm shifts. We feel we need them... but we don't. With the exception of a significant few... most of the SUV capabilities are not used with most trips. Look around on the next work day for those who are just driving by themselves to work. Company SUVs fine, but even Realtors drive the SUV to sell the McMansion lifestyles... its image and perception. I have no problems with V8 full size cars or auto lifestyles. I consider myself auto addicted and I love to drive for the sake of a drive. I still use transit and walk (I based my living area on a walkable distance on nice days) I know people to drive out of habit and yet live closer. Some even park further way than it would take them to walk from home. (I know the university setting is different but there are other abilities to live closer to work and yet we choose not to) Most turn the key and putter along without thought to the art and connection to the machine. I try and know every quirk of the drive and my car. it pains me not to wash my black car due to water restrictions. A sunday afternoon with "Pearl" is #2 in my hobby time sink next to the tank. But she sits dirty and pollen covered because there are issues such as drought that take priority over my auto addiction. The problem is when the unaware drivers are driving out of unaware habit without a thought of their overall actions... that is a problem when they insist on SUV's to maintain an dated lifestyle. I like big cars too, I remember my family's old '91 Cadillac Deville. It could get 30mpg highway... I got it as high as 33mpg on a trip from knoxville tn to richmond va(over mountains). The trick is that we assume we need the big vehicles for everyday use. (we buy them for vacations ect). The prius (although midsize) has as much rear leg room as the Caddy, more than the Lincoln towncar too. Im 6'3 and I can ride comfortably in the rear seats for hours. In fact, several 6ft+ males drive up to DC fairly often. My future father in law's four door (suicide doors) Silverado is tiny in legroom. He raises cattle so a truck is fine, but a school teacher does not need it. We have tricked ourselves into a way of thinking and refuse to leave. Station wagon can provide the same interior space as suvs but they are not "manly" enough... god forbid a minivan. Heck, the motor companies found the loophole in the emissions area, sold the "manly" and power image (works for female drives, especially the driving positions, fiancee included), sold them as "safe", and could have higher profits since they were light truck and cheaper to build. Funny thing is that the SUV were even marketed as "green/getting closer to nature". If one wants a "man machine, get a Pontiac G8... or a sportscar... thats fine. trucks (SUVs) are for work. Drive a real car when you ain't haulin' lumber, livestock, or machinery. It wasn't a fair fight, you could even get tax bonus for classifying the SUV as a work vehicle despite private use. It is just like transit, it was never a fair fight. Transit is subsidized, roads are funded... it is the same thing just different words and political reactions.

Ok, enough on the auto culture, but our lifestyles drive how we consume resources and create pollutions. I don't advocate going back to bang rocks together in mud huts, but we can't continue with the current pattern either. The world is showing the effects of our actions. We need to either create a new technology (that sifts the pollution burden to another arena) or we need to manage out resources better. There is just alot of inertia and old thinking (I am an expert on old thinking, I live in South Carolina!! ahaha ) that impedes progess. Change is scary and people are afraid of loosing their current understand of the world. The problem is that we are making it more difficult in preserving what we do because we refuse the need to acknowledge change. The benefits are not guaranteed and therefore people shy away form the new options until they are "proven" (still people don't adopt them)

Edit: wow my grammar is bad... still it is too late and I have writing papers all day... to lazy to correct it, forgive me.

 

[greenbean36191]

As far as solar changes I was referring to the ionization of the upper atmosphere which effects cloud formation...Cloudy days are cooler days. Cloudy decades are cooler decades.

It's possible, but so are lots of things that we don't have evidence for. We have no reason to assume it's the case though without evidence. There's just no clear evidence that it makes a substantive difference. Using only proven forcings already produces useful models, so it's wishful thinking to believe that this would be a game-changer if it did turn out to be true. We would simply have more precise models.

Take into account this winter.

What about it? It was unusually cold in the Northeast, but unusually warm on the west coast and parts of the South. At the same time it was summer in the southern hemisphere and an exceptionally warm one for large parts of Australia in particular. These are all examples of weather and aren't relevant to a discussion of climate or useful in evaluating projections. Not every year is expected to be warmer than the next and winter will certainly still be cold, even under the most extreme projections.

Also don't forget about the profit being made with carbon credits. I'm not a conspiracy nut but follow the money.

Look how many fortune 500 companies peddle in carbon credits. Look how many of them hire lobbyists. Look how many climatologists are getting rich these days.

What certain politicians or various groups have to say on the issue has no bearing on the science, which is unambiguous on the questions of whether CO2 is increasing, global temperature is increasing, and humans are having a hand in both. Whether entrepreneurs can figure out a way to exploit it to their gain is irrelevant.

I also cannot buy that seismographs can give an accurate representation of the amount of gas each eruption releases.

No, but it does allow us to detect when, where, and how big underwater eruptions are for better accounting type estimation. They make it very unlikely that there are many active undersea volcanoes that we don't know about, especially any producing orders of magnitude more CO2 than all the vulcanism we can account for.

Again though, this isn't the primary way we know the contribution of volcanoes vs. humans. Whether we did these estimates at all we would still know that anthropogenic CO2 is orders of magnitude more than volcanic CO2 based on the isotopic signature of the carbon in it. Volcanic CO2 and CO2 from fossil fuels is measurably different. We know the rough values of different sources and their relative contributions from direct measurement of atmospheric CO2.

We have direct measurements of change in atmospheric CO2 over time. We have direct measurements of the isotopic signature of that CO2 to tell us what sources it's coming from. We have accounting estimates to check against. If there are underwater volcanoes producing so much CO2 as to make our data unreliable, where is it all going? Why doesn't it alter the isotopic signature? Why can all other known sources account for the CO2 increase without including it? How is it affecting the climate yet remaining undetectable?

As far as CO2 in the ocean, I dump a lot of CO2 into my reef via a calcium reactor and my ph is between 8.1 and 8.3.

Think about what the calcium reactor does. You are adding the CO2 to drive down the pH to the point that the media, which is chemically the same as coral skeletons, dissolves and the carbonate from it neutralizes the carbonic acid (which is why the pH in the main tank is unaffected). I don't think most people would consider dissolving the worlds corals to buffer the ocean's pH an acceptable outcome.

My reef continues to grow under said conditions. I'm sure it’s the same for the ocean. I think temperature would have more of an impact in the way it affects certain enzymes within coral tissue and how certain pathogens thrive in a warmer environment.

How far temp can push coral reefs before they break is a pretty new area of study, but so far the data really don't support your supposition that it's a more urgent issue than acidification. Many reefs are close to their absolute temperature limits, but many aren't, and even under the worst case scenario of projected temp increase it would be close to the end of the century before temperature made all of the oceans inhospitable to reef growth.

Acidification on the other hand could realistically make all of the oceans inhospitable to net reef growth within ~40 years.

The reason is that reef growth in the ocean and in your tank are not comparable. Natural reefs are in a constant balance between positive growth from accretion and growth of corals and negative growth from breakage, dissolution, predation, and bioerosion. The net effect is that most reefs only have very marginally positive net growth and a large portion haven't seen positive growth in decades. Increasing negative growth or decreasing positive growth even slightly can cause a phase change from positive net growth to negative.

In reef tanks we don't have storms, have few coral predators, almost no bioeroders, and we try to maximize chemistry for growth vs. dissolution. As a result net reef growth is almost always strongly positive. You could frag a little more aggressively, lose a few corals here and there, or just slow growth due to poor water quality, and usually still come out way on top.

This means that a fairly minor change to your tank (say dropping the pH to 7.8) might have little effect, but in the wild, doing so would be disastrous.

As far as reefs I'm under the belief that costal development and over fishing impact the reefs in the most significant manner.

Currently, yes. In the near future, no.

Just out of curiosity I wonder what the CO2 levels and average temperature were when the Cretaceous Great Barrier Reef formed. Not sure but I think O2 levels were significantly higher.

The GBR and all modern coral reefs are much younger than the Cretaceous. The GBR is only a little more than half a million years old.

For part of the Cretaceous, CO2 and temp were much higher. Reefs did not fare well, which is the history Chris and I keep mentioning. Hard corals slowly stopped calcifying as CO2 increased and eventually stopped completely. There were no coral reefs for about the last 1/3 of the Cretaceous. Corals were replaced as the reef builders by a group of bivalves that went extinct themselves by the end of the Cretaceous. For the next several million years there was no reef building of any kind.

 

[greenbean36191]

Austin, first of all, per the user agreement religion and politics are both off limits here. They may be relevant to the discussion, but they breed bad blood, so we have to avoid them if we want to keep the thread open.

First, I wonder if anyone making these models are accounting Henry's Law

Yes. All of the major ocean and coupled GCM models take in into account the relationship between the solubility and temp as well as the interconversion of CO2<~>CO3(-2). Calculating the equilibrium values of all the intermediate species at various temps and atmospheric concentrations isn't trivial work, but it's very straightforward chemistry.

However, I sincerely doubt that the sun only functions on this ~11 year cycle.

It doesn't. There are several solar cycles ranging from decades to millennia long which are accounted for in the models.

One of the most comical aspects of these reports seems to be the insistence of the scientists that they base their calculations on the current level of human related CO2 production (which they assume will remain constant over the relevant time frame). Have the scientists not seen the projected curves of CO2 production? The ones that have the rate increasing at an increasing rate?

I'm not aware of any major study (other than theoretical exercises) that bases projections on a static CO2 value. The IPCC projections for example use non-linear increases in CO2 as well as breaking them down into business as usual, high economic growth, and low economic growth projections which make different assumptions about the rate of CO2 increase.

The trouble is that the projections have to assume some rate of CO2 increase, which is highly economically dependent and not constant. Things like recessions or rapid industrialization change the rate of CO2 increase. Unfortunately economics is hard to project, or we would all be rich.

...which brings up one of the key differences between projections and predictions. Predictions are what you get from a psychic and they don't rely on assumptions to test their validity. They either pan out or they don't. Projections assume that certain events in the future happen and then give a range of results that are likely to occur as a result. If the assumptions made in the projection turn out to be invalid then you don't have a valid test of the results. For example, the pre-1991 projections assumed no major volcanic eruptions (because they're random events). When Mt. Pinatubo erupted in 1991 the projections had to be revised downward because an assumption was violated.

I'm not sure if you meant to, but you do bring up an excellent point, which is that there is uncertainty in the models, but it's a two-way street. People who harp on the uncertainty of modeling often do so to suggest that it's likely the projections are too high. However, they usually fail to acknowledge that it's equally likely the uncertainty has resulted in a projection that's too low.

 

[MCsaxmaster]

Oh boy… Okay, there are few points raised above that I think are particularly important to respond to.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
As far as solar changes I was referring to the ionization of the upper atmosphere which effects cloud formation...Cloudy days are cooler days. Cloudy decades are cooler decades.

Actually, the evidence suggests that cosmic ray influx does not significantly affect cloud formation, or climate. See recent work in Lockwood and Frolich, 2007. Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature. Proceedings of the Royal Society; and Shiermeier, 2007. No solar hiding place for greenhouse skeptics. Nature.

There’s also no evidence for long-term trend in low cloud cover. To suggest that variation in cosmic ray influx, as related to solar activity, could be related to climate change for at least the last 30 yrs is simply false. The evidence demonstrates the opposite.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
Thanks for your detailed response. I’ve read arguments and talking points on both sides and still feel that the models are not reliable.

Not reliable how? They certainly do a good job of projecting climate trajectories. They’re less good at projecting trajectories over small spatial scales or very short timescales, hence no one claims that we can project that.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
Take into account this winter.

In the Eastern US we had a chilly January. In the Western US they had a warm January. In South Australia they had a severe heat wave. None of these observations means much for the long term. By analogy, a cold snap in March does not mean that summer will not come; an Indian Summer in October doesn’t mean winter isn’t on its way. A hot or cold few weeks in small area (relative to the globe) really doesn’t mean anything meaningful for climate.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
As far as CO2 in the ocean, I dump a lot of CO2 into my reef via a calcium reactor and my ph is between 8.1 and 8.3.

Ha, well you inject CO2 into a chamber isolated from the main tank for the purpose of dissolving aragonite (raising alkalinity and calcium), and then allow excess CO2 to degas from the tank into the room air as quickly as possible, thereby suppressing pH only slightly. That’s not the same process as ocean acidification, and by a long shot

If you were to raise the pCO2 in the room to a high level, aerate heavily, and have only a tiny amount of solid CaCO3 relative to the volume of your tank, then you’d begin to approach replicating ocean acidification in the coastal ocean. As in the real ocean, calcium and alkalinity would be about constant and pH and CO3= concentration would drop like a rock.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
Algae and bacteria are wonderful buffers along with aragonite.

In order to prevent oceanic pH from dropping around coral reefs it would take a massive increase in photosynthesis to suck up all the excess CO2, and thereby prevent pH from dropping. If that actually happened, atmospheric CO2 would be a constant, when clearly it is not Most marine algae actually experience no change, or very little change, in the rate of photosynthesis upon CO2 enrichment. Hence, they don’t suck up the extra CO2/HCO3- and oceanic pH remains suppressed. That’s what we would expect based on the physiology, and that’s what we have measured in the real world.

Aragonite doesn’t begin to dissolve until the water becomes undersaturated. Hence, aragonite dissolution is an insignificant buffer against ocean acidification, at least on timescales less than thousands of years (see work by Andersson et al. and Archer for more detail).

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
My reef continues to grow under said conditions. I'm sure it’s the same for the ocean.

Sure, at normal pH and normal to high alkalinity and calcium all sorts of marine organisms do great, just as in your tank. The issue here is what happens with reduced pH (and associated changes in chemistry) with normal calcium and alkalinity (although both are low, geologically speaking). As above, we have telling geologic evidence. The last time something similar to this happened coral reefs disappeared for several million years and the ocean experienced widespread extinctions.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
I think temperature would have more of an impact in the way it affects certain enzymes within coral tissue and how certain pathogens thrive in a warmer environment.

Yes, the effects of temperature on physiology and on pathogens are very important issues as well.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
As far as reefs I'm under the belief that costal development and over fishing impact the reefs in the most significant manner.

Indeed, one would think that severe local impacts (coastal development, fishing) would have had a major impact, even if not as large as regional stressors, such as ocean warming. I certainly would have thought so, but several recent studies (e.g., Selig et al.) have found precisely the opposite. While local impacts can and do have an impact on local reefs, corals that have been protected for years to decades fair no better than those subject to pretty significant exploitation. MPAs can help protect fish, but they don’t do a darn thing for corals, it turns out. Instead it’s the really big impacts (regional to global bleaching events, disease outbreaks, COTS outbreaks, etc.) that are driving coral health and abundance on most reefs.

<a href=showthread.php?s=&postid=14685491#post14685491 target=_blank>Originally posted</a> by wld1783
Just out of curiosity I wonder what the CO2 levels and average temperature were when the Cretaceous Great Barrier Reef formed. Not sure but I think O2 levels were significantly higher.


Bill

Reef formation was strong during the early Cretaceous, but petered out toward the end, and disappeared entirely for several million years at the K/T mass extinction. Most coral species went extinct. In fact, most genera went extinct, and the families that got through barely did.

CO2 levels near the end of the Cretaceous were ~ 1000 uatm, but were higher earlier in the Mesozoic (as high as 2000-3000 uatm). Calcium concentration and alkalinity were also substantially higher though. Calcium was 3-5x present day levels (1200-2000 ppm) during different parts of the Mesozoic while alkalinity was perhaps 2-3x what it is today (~4-6.5 meq/l). Magnesium was also about half of what it is today, which has important implications on CaCO3 polymorph selection.

An important point to keep in mind is that atmospheric CO2 is only one of several components that help to determine rates of CaCO3 precipitation and biomineralization. Calcium concentration and alkalinity are just as important a consideration as atmospheric CO2.

During the Mesozoic we had high calcium, alkalinity, and CO2. Unsurprisingly, we got lots of biomineralization. During the preindustrial we had low calcium, alkalinity, and CO2 (geologically speaking) and got lots of biomineralization. We are rapidly changing the situation such that we will have low calcium and alkalinity, but high CO2. What happens to the biota when those changes take place? As with the PETM, mass extinction and the global disappearance of reefs are among the more worrisome outcomes.

cj

 

[MCsaxmaster]

<a href=showthread.php?s=&postid=14686123#post14686123 target=_blank>Originally posted</a> by MayorOfWhoVille
First, I wonder if anyone making these models are accounting Henry's Law: at a constant temperature, the amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid (I assume this is accounted for). Basically, more CO2 in the air means more CO2 in the water.

Without belaboring the point, yes, the partitioning of CO2 between the atmosphere ocean (Henry’s law is a piece of that puzzle) is one of the basics. We just haven’t mentioned it much here

<a href=showthread.php?s=&postid=14686123#post14686123 target=_blank>Originally posted</a> by MayorOfWhoVille
Another factor possibly being overlooked is the fact that the CO2 solubility in water decreases with a rise in temperature. So even as we pump more CO2 into the air and the poor ocean does it's best to follow Henry's Law at constant Temp, the world and ocean warm and the ability of the ocean to dissolve CO2 is decreased (the concentration of CO2 in the ocean still goes up, but not in a linear fashion with partial pressure). I also wonder how one accounts for the non-ideal aspect of this situation, namely the fact that the CO2 reacts with the solvent to produce H2CO3, an equilibrium that is also affected by temperature. Maybe these effects are too small to be of importance? I suppose the actual increase in temperature is fairly small and probably negligible, but hey, this is a planet's worth of ocean we are talking about here: is even a small effect really negligible?

As above, all of these effects are very well understood and are taken into effect, we just haven’t been discussing them here

<a href=showthread.php?s=&postid=14686123#post14686123 target=_blank>Originally posted</a> by MayorOfWhoVille
Second, there seems to be a general consensus that the fluctuation of the suns' radiation is not and will not be a major factor in global warming. Assuming that the trends in the data collected from roughly 40 years of monitoring the sun from space and roughly 200 years of earthly observation of sun spots holds true for the foreseeable future, this may well be the case. However, I sincerely doubt that the sun only functions on this ~11 year cycle. I suppose we have enough to worry about without the sun increasing or decreasing its activity level over a period of more than a couple of hundred years. I only bring this up because of an article I read awhile ago talking about the flareups of other stars of similar solar mass and composition, suggesting that the seemingly docile nature of our star is an illusion based on the brevity of reliable observation.

We actually have good estimates of solar activity for much longer periods of time. The best, most complete data cover the last 30 yrs or so, but we have data extending back much further than that.

The issue is not whether or not variation in solar activity can affect climate: clearly it can and does. The issue is how much the possible range of variation in solar activity can affect climate. If the sun got ‘stuck’ in a mode of low output for the rest of this century the cooling effect would be counteracted by only ~ 5 yrs of CO2 increase at our current rate. While variation in solar output has an effect, the range of possible variation is much smaller than the effect of increasing greenhouse gas concentration.

Again, all of this is taken into account in the range of expected outcomes, we just haven’t been discussing it.

<a href=showthread.php?s=&postid=14686123#post14686123 target=_blank>Originally posted</a> by MayorOfWhoVille
Third, I seem to notice a trend in the reports coming from committees and scientists concerned with global warming. The trend is for the models and data to suggest mild to moderate warming over the course of the next century or so, until the next report comes out which suggests mild to moderate warming in the next fifty years, until the next report comes out suggesting mild to moderate warming over the next 20 years. This is a disturbing trend.

I’m not necessarily sure that’s so: our estimates of the range of warming for a given increase in greenhouse gas forcing haven’t changed much. Really what has improved is 1) our understanding of what a temperature change of X will do to parameters A, B, and C, and 2) our the increase in CO2 emissions are rising faster than expected even just a few years ago.

<a href=showthread.php?s=&postid=14686123#post14686123 target=_blank>Originally posted</a> by MayorOfWhoVille
The predicted rate of glacial and ice sheet melting seems to follow this trend as well.

In the sea level projections by the IPCC they have taken into account thermal expansion only, and not ice sheet dynamics because, until very recently, our understanding of ice sheet dynamics weren’t good enough to make confident projections on their contribution to sea level rise. When taking into account only thermal expansion we expect ~1-2 ft of sea level rise by 2100, without mitigation, which is why these projections underestimate sea level rise over recent decades. When taking into account thermal expansion AND the contribution of melting ice sheets we expect more like 3-6 ft of sea level rise by 2100, without mitigation, which is in good agreement with observational data.

<a href=showthread.php?s=&postid=14686123#post14686123 target=_blank>Originally posted</a> by MayorOfWhoVille
In short it seems that the more we look into the problem the more it looks like we are totally screwed over in a shorter and shorter interval. One of the most comical aspects of these reports seems to be the insistence of the scientists that they base their calculations on the current level of human related CO2 production (which they assume will remain constant over the relevant time frame). Have the scientists not seen the projected curves of CO2 production? The ones that have the rate increasing at an increasing rate?

Huh-uh, all projections use several different scenarios that capture the range of possible human behavior, with regard to emissions. However, CO2 emissions are actually above the classical “business as usual” scenario, IS92a, and are about on the A1F1 scenario, which would get us to ~980 uatm CO2 by the end of the century.

cj

 

[Megalodon]

<a href=showthread.php?s=&postid=14586439#post14586439 target=_blank>Originally posted</a> by Randy Holmes-Farley
Folks reading this should recognize that the "30% more acidic" they mention corresponds to a drop of 0.11 pH unit.

So however you choose to interpret it, folks with reef tanks at pH 7.7 to 7.9 are experiencing conditions much more acidic than the article is referring to.

pH 7.7 is more than 300% more acidic than NSW at pH 8.2.

Hi Randy!

I'm just curious to know what you think of all this. What effects is this currently having on the ocean?

If CO2 levels continue to rise, what effects then do you think it could have in the future?

 

[Megalodon]

<a href=showthread.php?s=&postid=14663503#post14663503 target=_blank>Originally posted</a> by wld1783
e tend to make things worse like putting out forest fires or driving a Chevy Prius...lota of heavy metals in that battery, not good for land fills.

Nasty chemicals indeed, but those batteries are recycled, aren't they?

 

[wld1783]

greenbean36191

Thanks again for the detailed response. I do agree that politics and religion are unacceptable in this forum. Some may argue that Climate Change is both I disagree and would like to keep former president and vice president bashing out of this discussion.

I am truly curious and the facts. I would like to skip the talking points and would like someone to "show me the money" I would like to know a hard number of how many millions of tons of CO2 mother nature produces and not a guess using a seismograph to measure CO2, and I would like a refresher on how many million tons we produce.


Quote" quote:
--------------------------------------------------------------------------------
As far as CO2 in the ocean, I dump a lot of CO2 into my reef via a calcium reactor and my ph is between 8.1 and 8.3.
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“Think about what the calcium reactor does. You are adding the CO2 to drive down the pH to the point that the media, which is chemically the same as coral skeletons, dissolves and the carbonate from it neutralizes the carbonic acid (which is why the pH in the main tank is unaffected). I don't think most people would consider dissolving the worlds corals to buffer the ocean's pH an acceptable outcome."

I try to focus on what is. To keep a narrow view on things is like a horse with the blinders on. It only sees what the driver wants it to. There are a few grains of sand in the ocean and I'm sure that will help along with algae. I really don’t think a 10% increase in CO2 would be "dissolving the worlds corals". It may or may not warm things up though. That is only my opinion and I might be wrong.

I've always believed an ecosystem is much like a true market economy. I am neither a professor nor a PHD only a MA, but my job leaves me ample time to read. In a true market economy and you discover oil and then make gasoline. You make it for 10 cents a gallon and offer it for sale. All of a sudden cars start popping up everywhere maybe even a statistically proven unsafe SUV. These cars then consume the gas till eventually there will be none. Algae, plants some bacteria all consume CO2 like a car consumes gasoline. The more available CO2 the happier and more abundant these organisms become and so do the organisms that feed on them. Then they die. Some rot and release CO2 back others sink to the bottom through the natural food chain. This may be our next proven oil reserve millions of years from now as much of the middle east was once a vast reef. As long as we have an adaptable ecosystem I don’t worry about CO2. Coastal development and over fishing are a different matter.

As far as the quote" You're confusing weather and climate. Statistically speaking weather is noise and climate is signal. Noise is chaotic and hard to predict and signal is the long term average once you smooth the noise out. It's less prone to randomness."

A Total Talking Point and misleading. As a Jet Captain I relay on this chaotic noise on a daily basis. I know with a high degree of certainty what the weather will be like at my destination several hours away and what it will be like the next day, and in most cases the day after. Nobody can tell me what the winds will be like next week or weather or not (pun intended ) that front will produce that thunderstorm over my destination at my arrival time. When the models do that then I might start drinking the cool aid. As of now they cannot predict the rainfall in the Mid West this spring. Think of the advantage farmers will have if they have an accurate estimate on the spring rainfall. Am I really supposed to believe that they can predict the temperature 30 years from now.

BTW using a 30 year reference IMHO is like judging the success of a student by one semester. They should be looking longer . And yes it was warmer down under but what was the total global temp change this year?

Bill

 

[wld1783]

MCsaxmaster

Thanks for you response I'll google Lockwood and Frolich, 2007. I read the cloud theory in scientific journal with no other supporting articles to back it up.

If the sand wont buffer the CO2 is their evidence of algae plankton and bacteria stepping up to the plate?

Excellent point about partial pressure its true with O2 at high altitude as well


Bill

 

[wld1783]

<a href=showthread.php?s=&postid=14692694#post14692694 target=_blank>Originally posted</a> by Megalodon
Nasty chemicals indeed, but those batteries are recycled, aren't they?

Bill

 

[Megalodon]

<a href=showthread.php?s=&postid=14692913#post14692913 target=_blank>Originally posted</a> by wld1783

The batteries for things like hybrids... the metals in them are recycled and reused (instead of ending up in landfills and having to be re-mined) aren't they?

I don't know, I'm just asking. I hope that's more clear.