Hi all,
Since the extent to which climate change is human induced was a point of discussion during our meeting today, I thought I'd post a few resources which address this questions:
From the Intergovernmental Panel on Climate Change (IPCC):
http://www.ipcc.ch/about/about.htm: About the IPCC
http://ipcc-wg1.ucar.edu/wg1/wg1-report.html: This is the IPCC's 4th Assessment (2007), from Working Group #1, discussing the physical basis for climate change.
http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch09.pdf: Chp. 9 of the assessment, which specifically addresses the role of anthropogenic forces and other influences.
http://ipcc-wg1.ucar.edu/wg1/Report/AR4_UncertaintyGuidanceNote.pdf: This explains some of the probabilistic terminology used.
From the BBC:
http://news.bbc.co.uk/2/hi/science/nature/6290228.stm: This is where I'd read that a study concluded that solar output has been decreasing recently. I'll grant you that the BBC sounds somewhat biased and that they aren't exactly the best source of info... :)
From the Program for Climate Model Diagnosis and Intercomparison:
http://www-pcmdi.llnl.gov/: Haven't explored this too much yet, but looks interesting!
Well, I'd like to post more, but I've got to get to our church potluck in a few minutes...I'll try to get back to post more later; in the meantime, I suppose this is good starting point for debate :)
In Christ,
Christine
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32 comments:
Christine: Thanks for the references you listed. I will take a look at them. Have you read anything by Dr. S. Fred Singer, Professor Emeritus of Envirnmental Sciences at the Univ. of Virginia? Ph. D. from Princeton, founding director of the U.S. National Weather Satellite Service, and served as vice chairman of the U.S. National Advisory Committee on Oceans and Atmosphere. His most recent book is Unstoppable Global Warming: Every 1,500 Years.
I have a copy of a lecture he delivered on the Hillsdale College campus on June 30, 2007, at a seminar entitled "Economics and the Environment." Bruce
Christine, Thanks for the links. I look forward to reviewing them and discussing them more.
I hope your potluck was great, and am sorry to have missed the fellowship on Saturday.
Regards,\
Ed
Hello all,
Bruce--nope, haven't read it...alas, I suppose one of the disadvantages of being young is not being well-read--but I'm working on that! I'll add that to my very long reading list :)
Feel free to post the lecture though if he'd be ok with that--I'd be interested in reading it.
Ed--missed having you there! The potluck was quite tasty :) By the way, is it possible to post responses to individual comments?
In Christ,
Christine
Bruce,
I just visited wikipedia (I know, not the best source out there) to see what they said about Dr. Singer; my impression based on what is written there is that his thesis is that climate change is occuring, but is due to variations in solar activity. If this is what his contention is (and do correct me if I'm wrong), what does he postulate concerning the rise in CO2 (and other greenhouse gases) concentrations in the atmosphere? Does he dispute them? If not, then is his contention that this does not contribute to warming and/or that this rise is not caused by humans? Just curious, since I probably won't get around to reading the book for awhile :)
In Christ,
Christine
I think what most skeptics are skeptical of is the AGW narrative - Anthropomorphic Global Warming- that is so popular today.
Of course GHGs contribute to the climate. What AGW imposes, however, is the belief that GHGs drive the climate. AGW does this at the expense of geologic causes of things like sea level changes, at the expense of paleo-climate evidence, and more. It becomes basically a story about CO2. I do not believe that the models or the evidence is anything like compelling to lay climate driving on CO2 alone.
A big issue today is that Hansen, and other climatologists who have pushed AGW so hard, are admitting big holes not only in their data sources but in their analysis of the temperature facts. Until just the last week or so, Hansen had never released the analytical tool he has used to make his AGW predictions.
I think what we are seeing in the long list of cites you posted is a self-referential list of conclusions, all based on very thin science.
Unlike the AGW true believers, I find the skeptical position to be more nuanced and open to new data. I see this demonstrated when climate results counter to those of AGW predicitons are still claimed as proof of AGW. I see this when studies that cast doubt on AGW, or scientists who question AGW, are vilified or accused of being corrupt.
I see more of a fundamental religion in extreme AGW than a science, frankly.
Christine: Here is an excerpt from Singer's presentation at June 30, 2007 seminar "Economics and the Environment" at Hillsdale College, sponsored by the Charles R. and Kathleen K. Hoogland Center for Teacher Excellence:
"Natural Causes of Warming
A quite different question, but scientifically interesting, has to do with the natural factors influencing climate. Natural factors include continental drift and mountain-building, changes in the Earth's orbit, volcanic eruptions, and solar variability. Different factors operate on different time scales. But on a time scale important for human experience - a scale of decades, let's say - solar variability may be the most important.
Solar influence can manifest itself in different ways: fluctuations of solar irradiance (total energy), which has been measured in satellites and related to sun spot cycle; variability of the ultraviolet portion of the solar spectrum, which in turn affects the amount of ozone in the stratosphere; and variations in the solar wind that modulate the intensity of cosmic rays (which, upon impact into the earth's atmosphere, produce cloud condensation nuclei, affecting cloudiness and thus climate).
Scientists have been able to trace the impact of the sun on past climate using proxy data (since thermometers are relatively modern). A convenient proxy for temperature is the ratio of the heavy isotope of oxygen, Oxygen-18, to the most common form, Oxygen-16.
A paper published in published in Nature in 2001 describes the Oxygen-18 data (reflecting temperature) from a stalagmite in a cave in Oman, covering a period of 3000 years. It also shows corresponding Carbon-14 data, which are directly related to the intensity of cosmic rays striking the earth's atmosphere. One sees there a remarkably detailed correlation, almost on a year-by-year basis. While such research cannot establish the detailed mechanism of climate change, the causal connection is quite clear: Since the stalagmite temperature cannot affect the sun, it is the sun that affects climate."
Hello all,
I don't have a lot of time (am just finishing up my lunch break at the moment), but I wanted to post a quick response to the comments...
By the way--who posted #5?
"I think what most skeptics are skeptical of is the AGW narrative - Anthropomorphic Global Warming- that is so popular today.
Of course GHGs contribute to the climate. What AGW imposes, however, is the belief that GHGs drive the climate. AGW does this at the expense of geologic causes of things like sea level changes, at the expense of paleo-climate evidence, and more. It becomes basically a story about CO2. I do not believe that the models or the evidence is anything like compelling to lay climate driving on CO2 alone."
As far as I have read, AGW science does not conclude that GHGs drive the climate at "the expense of" geologic causes; rather, it states that these influences are not enough to explain present observations, and that what is CURRENTLY the dominant (but not only force) influencing the climate is an increase in GHG atmospheric levels due to human activities. Also, I'm sure you're aware that although CO2 is primary culprit for AGW, there are many other GHGs which have resulted from human activities including: methane, nitrous oxide, sulfur hexafluoride, CFCs, and HCFCs. Many of these are more potent GHGs than CO2; indeed, proponents of AGW are actively engaged in finding ways to reduce these other GHGs as well. So, I wouldn't characterize AGW as being "basically a story about CO2".
"A big issue today is that Hansen, and other climatologists who have pushed AGW so hard, are admitting big holes not only in their data sources but in their analysis of the temperature facts."
Can you cite case(s) where Hansen and others have admitted "big holes"? I am aware that recently they made a very small correction (on the order of a hundreth or thousandth of a degree) to the data, but my understanding is that this did not change the underlying trends.
"I think what we are seeing in the long list of cites you posted is a self-referential list of conclusions, all based on very thin science.
Well, I wouldn't say that I posted a "long list" of references :) That was just meant to be a starting point...
"Unlike the AGW true believers, I find the skeptical position to be more nuanced and open to new data."
Although I'm not a climate scientist myself, I would consider myself to be a "true believer" in AGW; I would also say I am open to new evidence, in so far as I'm able to evaluate it myself. Of course, that becomes more difficult when it is outside my field of study, as is true for all of us.
"I see this demonstrated when climate results counter to those of AGW predicitons are still claimed as proof of AGW."
Could you cite case(s) in which evidence contrary to AGW is used as evidence for it? I realize that evidence can surface in which AGW needs to be refined or modified (as with any other scientific theory), but I don't recall any cases where evidence has been cited for AGW that completely undermined it.
"I see this when studies that cast doubt on AGW, or scientists who question AGW, are vilified or accused of being corrupt.
I see more of a fundamental religion in extreme AGW than a science, frankly."
Obviously, I wouldn't support suppression or vilification of scientists who are asking honest questions and scrutizing the evidence at hand. And certainly, I will grant you that there are some who become so extreme as to have a sort of "religious" zeal for it. But I think this could be said about some "deniers" as well, and more generally, such is probably the case for all scientifically controversial issues (i.e. evolution vs. creationism). However, I don't believe that this represents the majority of AGW proponents.
Regarding the excerpt on cosmic rays, I'm not sure I follow the argument...is he arguing that because oxygen and carbon isotopes in this stalagmite are correlated, and because the carbon isotopes are influenced by cosmic rays, that this provides evidence that cosmic rays have a signficant impact on the climate? Three related questions: 1) it's been awhile since I studied caves--are the isotopes representative of the isotopes contained in the water, the cave's atmosphere, or both? 2)if the cave's atmosphere is a factor in this, how does he account for the differences between the cave's atmosphere and the surface atmosphere (both in terms of chemistry and meteorlogy attributes (temperature, etc))? 3)Surely there are other factors influencing the levels of oxygen and carbon isotopes, yes? What are these and how are these accounted for?
From an AGW website, a discussion of their interpretations regarding the cosmic ray theory:
http://www.realclimate.org/index.php/archives/2007/03/cosmoclimatology-tired-old-arguments-in-new-clothes/
Finally, from the excerpt:
"While such research cannot establish the detailed mechanism of climate change, the causal connection is quite clear: Since the stalagmite temperature cannot affect the sun, it is the sun that affects climate."
I find it remarkable that although he "cannot establish the detailed mechanism of climate change" with the research he cites, he nevertheless makes the sweeping statement that the "causal connection is clear". Correlation does not prove causation, and it would seem anything but clear to me. Also, what AGW scientist doesn't think that the Sun affects the climate? I don't find this statement very helpful, and it certainly does not negate the role that GHGs play (human influenced or otherwise).
In Christ,
Christine
OK--well, so much for not a lot of time...will have to stay late today... :)
Christine,
Thank you for your comments. I appreciate your patience a lot. I posted comment#5 (Ed). I ended up being tagged with the name of the blog, for some reason.
It is late, and I have to get to bed, but I will offer a small example of how AGW believers seem to take all results as proof of AGW in another post. Again, thanks for taking the time for such a thoughtful post.
Just wanted to say I read all these with interest, and am continuing to follow the discussion! I don't have anything to add yet; Christine's asked good questions and I await Bruce and Ed's answers.
Hello all,
As an FYI--through an unrelated thread on the main ASA listserv, I learned that C14 can form secondarily by nitrogen in the rocks capturing neutrons given off during normal uranium radioactivity. Not sure if you already knew that (it was news to me, anyway) but figured that might be pertinent to the cosmic ray/stalagmite discussion.
In Christ,
Christine
My guess on the O and C isotopes in the caves is that it's the isotopic composition of the groundwater that filters down into the cave and from which the CaCO2 in the stalagmites precipitates. I would guess that any isotopic fractionation processes occuring in the groundwater path to the cave or in atmospheric exchanges in the cave would be small and probably constant and therefore should not drive the correlation he's finding. The oxygen-18 isotope thermometer I've always heard of is temperature-related fractionation of oxygen isotopes in seawater in the open ocean due to different amount of evaporation due to temperature. I don't think any temperature or chemical fractionation processes on the Earth's surface would be strong enough to change that signature very much when it trickles down into a cave - and as I said, I think those minor changes would be constant.
That would be my guess as to the degree of influence of C-14 from N due to neutron capture from uranium as well. Should be constant, not fluctuating.
It seems he's proposing that cosmic ray flux increases when solar solar wind shielding Earth decreases (and vice-versa), and solar wind flux is related to solar activity (whether inversely or directly, I don't know), and he sees a correlation between C-14 as a proxy for cosmic ray flux and oxygen-isotope variations as proxies for global surface temperatures over the last 1,500 years.
I agree with Christine that it would be good to know if he's advocating this as the driver of climate change, dominating all other factors such as GHGs. Judging by his title, I'd guess that he is.
I still need to read some of the references Christine gave, to see how they come to the conclusion that GHGs drive climate change at present. The IPACC document seems like a fundamental reference to have read on this subject, since it is supposed to be the consensus of world governments and world scientists on the subject.
Hello all,
On the subject of isotope fractionization in groundwater, I opened up my dusty geochem. book (Principles and Applications of Geochemistry, by Gunter Faure, 2nd Ed. 1998) to see what I could dig up...here's some excerpts:
Under the section: "Isotope Fractionation in the Hydrosphere":
There is a "latitude effect on the [O18 and D] isotope composition of meteoric water caused by 1) progressive isotope fractionation association with condensation of water vapor and the removal of water droplets from the air mass 2) the increase of the isotope fractionation factors caused by a decrease in temperature 3) the reevaporation of meteoric water from the surface of the Earth, and 4) evapotranspiration of water by plants. Since H and O occur together in water molecules and since both experience the same sequence of events during the migration of air masses, the [delta symbol]D and [delta symbol]O18 values of meteoric water are strongly correlated and satisfy an emperical equation known as the meteoric water line [refers to figure and equation]"
and later...
"The strong dependence of the isotope fractionation factors of O and H in meteoric water on the temperature of evaporation/condensation gives rise to a relationship between the [delta symbol]O18 value of meteoric precipitation and average monthly temperatures...The temperature dependence of [delta symbol]O18 and [delta symbol]D values of snow accumulating in the polar regions is reflected in seasonal variations of these parameters, which thereby record long-term changes in climatic conditions."
From the section "Groundwater and Geothermal Brines":
"The isotope compositions of O and H in groundwater are altered by isotope exchange reactions with the rocks in which the water occurs. The magnitude of this effect increases primarily with temperature and with the subsurface residence age of the water, but depends also on the mineral composition of the rocks and on the presence of other substances such as hydrocarbons and H2S(g). Several of these environmental properties, including temperature and residence age of the water, may increase with depth below the surface."
It then goes on to describe five different types of groundwater: meteoric (derived from surface water & precipitation), connate water (deposited with sediments), diagentic (released through chemical reactions in minerals), formation ("exists in layers of sed. rocks prior to drilling regardless of its origin"), and brine (salty).
A mathematical/technical discussion with examples follows, and the section concludes with:
"Evidently, the isotope composition of groundwater can be understood also as a result of mixing of waters of different compositions and origins. Meteoric water percolating downward from the Earth's surface may mix at depth with brines that may themselves be mixtures of connate water and highly reequilibrated old meteoric water. The resulting water compositions also lie in the area of reequiliabrated meteoric water [refers to Figure]. Therefore, mixing is an important process affecting the isotopic and chemical composition of groundwater in ways that may be indistinguishable from the results of progressive chemical and isotopic equilibration between rocks and water in the subsurface (refers to Lowry et. al, 1988)."
A number of questions come to mind...if there's a latitude dependence on O18, was this addressed in the Nature study? (maybe someone who has a subscription to Nature could bring this to the next meeting to look at?) I don't know how applicable the groundwater and geothermal brines section is to a more generalized understanding of O18 isotopes in groundwater, but it would seem to me that this would at least indicate the need to characterize the specific geologic conditions around and in the cave environment--was this done in the study? Did they make any adjustments or assumptions in this regard?
As to the C14 data...it occurs to me--what is the "C14 data" being referred to? Organic material deposited by the water? C14 absorbed by the water directly from the atmosphere (cave or otherwise?) as part of the typical CO2 absorbtion process? I'm not trying to be annoying with these questions--just trying to better understand a topic that is admittedly not my forte....
In Christ,
Christine
Hello again,
Okay, I just wrote up a long post only to have it disappear on me when I tried to edit my preview--not happy!! :I
I will try to reconstruct what I wrote...
I found the paper that Singer referred to; you can read it here:
http://www.geo.umass.edu/climate/papers/neffetalnature2001.pdf
The paper clarified several of my questions:
- The C14 data mentioned is tree ring data, and is being used as a proxy for solar activity and cosmic rays
- The O18 data is being used as a proxy for rainfall intensity, not temperature.
- The stalagmite was dated using U-Th
The paper's conclusions are:
"In summary, the d18O record of the stalagmite H5 from Hoti cave
represents a precisely dated high-resolution time series of the
intensity of Indian Ocean monsoonal rainfall. The strong similarity
between the smoothed secular variation curves of the H5 d18O
isotopic record and the D14C recordĂtogether with their spectral
analysesĂsuggest that both are responding to the same climate
forcing. Much of the variation in D14C is attributed to solar forcing
through variations in solar activity and intensity7."
They then present the following interpretation:
"The variations in solar irradiance necessary to cause
the observed changes in D14C are probably of the order of a few
tenths of one per cent (ref. 2). Such minor variations are unlikely to
have directly caused signi®cant differences in sensible heating of the
Tibetan plateau. It is more likely that solar variability leads to
changes in atmospheric or oceanic circulation that amplify this
initial input."
Here's my perspective/critique (again!!):
1) Judging by the provided excerpt, I think Singer overstates the conclusions of this paper. Singer stated that "One sees there a remarkably detailed correlation, almost on a year-by-year basis." However, in the paper, the authors state that "We emphasize
that the tuning was done while always remaining within the
measurement error of each of the 12 Th±U ages along the pro®le,
so that the net shift of any part of the d18O curve is only 190 years at
most (Fig. 3)." It would seem to me that a shift of up to 190 years is not "almost year-by-year". Further, the unsmoothed and smoothed correlations were listed as having the values r=0.55 and r=0.6, respectively. Although this is a good agreement, I would think that if the correlation were "almost year-by-year" that the correlation value would be a lot higher.
2)I find it interesting that although Singer states the influence of cosmic rays on climate is because it changes cloud dynamics, the paper itself concludes it is amplification of small variation in solar activity amplified by other climatic differences (non-cosmic ray related) which do this. I would think that if cosmic rays were an important climatological factor to consider, the authors would at least have evaluated this as a possibility.
3)On the subject of cosmic rays...it is my understanding that cosmic rays are supposed to influence climate by producing more cloud condensation nuclei (CCN), thereby enhancing cloud formation. However, as far as I can tell, this mechanism is tenuous at best, and still very controversial. Moreover, it's my understanding that the atmosphere already contains an abundance of CCN--thus, it would seem to me that you would have to show that clouds formed *preferentially* on CCN generated from cosmic rays in order to show a signficant climatological influence. Likewise, if cosmic rays come from not only the Sun, but also the rest of the galaxy, then wouldn't you have to be able to separate out the cosmic ray CCNs coming from solar activity vs. other cosmological sources, in order to show that solar activity is the culprit? And also, the AGW link I posted earlier specifcally says that according to our measurements, cosmic rays have not shown a declining trend within the past 50 years, which would be necessary, presumably, to show that fewer clouds are being formed and we are receiving more solar radiation, thereby warming the planet.
4)I also found it interesting that the paper noted that the solar activity changes would not have generated "signficant differences in sensible heating" which I presume would refer to surface temperatures. In many parts of the world today, we are seeing noticeable changes in temperature averages; if the increased solar activity did not cause such changes then, why should we assume that such changes would be evident now in response to changes in solar activity? I suppose one could argue that today's variations in solar activity are being amplified by other climatological systems, and that temperature changes are resulting from those, but I think we'd need to flesh this hypothesis out some before applying it to the current warming trends.
5)After all of this, I still have to ask the question--what about the rise in GHGs? We have records of a significant increase in GHGs beginning right around the Industrial Revolution, which correlates well with increases in global mean temperatures. The models must include human-generated GHGs (along with other natural influences) in order to accurately simulate the historical climate. If it is cosmic rays and solar activity driving present day climate change, why isn't this factor showing up more strongly in the modeling? I suppose you could argue that the mechanisms for solar activity influences are wrong in the models, and that the incorporation of the GHGs just coincidentally correlates well, thereby hiding the error...but it seems to me that this does not make sense. We know with a high degree of certainty what GHGs are, what their role is in the climate (greenhouse effect), and about how much we've put out; and when we evaluate this hypothesis, we see the results seem to fit. It seems to me that this is the simpler explanation, and that even if cosmic rays are shown to play a role, that this will never be as large of a factor as GHGs.
Anyway, I that's enough for the moment (again). Happy analyzing!
In Christ,
Christine
PS--one more point I wanted to highlight...the paper states that "The parallel evolution of d18O and D14C
seems very unlikely to have occurred by chance. Rather, the high
correlation provides solid evidence that both signals are responding
to the same forcing." I'm not sure I'd be so quick to see this correlation as "solid evidence". As you know, correlation does not equal causation; rather, it indicates relationships. There could be other spurious variables involved. Maybe it was just a word limit that kept them from doing so, but I would like to have seen an evaluation of what other variables could have explained the correlation.
Hello all,
A new study has been published in Nature describing an overall increase in humidity levels which the authors specifically attribute to AGW. Here's the link to the abstract:
http://www.nature.com/nature/journal/v449/n7163/abs/nature06207.html
If you're like me and don't have a subscription to Nature, you can get the general summary of their research here:
http://www.nature.com/news/2007/071011/full/news.2007.158.html
In Christ,
Christine
Christine,
That is a very interesting article. What they are basically saying, if I understand it, is that if the air is warmer then it can hold more moisture. They are not actually stating, it seems, that the air is more humid, only that its H2O capacity is larger. But at its core, this is yet another paper that takes the basic assertion of AGW and showing a rather well-known attribute of warmer air - increased H2O capacity. It still does not speak to the core issue - are we heating up much, will we heat up much, and is human activity uniquely responsible for it if it is happening?
Hello,
I am speaking somewhat from ignorance here, since I don't have access to the actual article (perhaps I should get a subscription!); but in the abstract the authors state that:
"We identify a significant global-scale increase in surface specific humidity that is attributable mainly to human influence. Specific humidity is found to have increased in response to rising temperatures, with relative humidity remaining approximately constant."
I had thought one of the links I posted specified this increase, but it didn't; here it is mentioned in a different article:
http://www.chron.com/disp/story.mpl/ap/science/5204399.html
"The amount of moisture in the air near Earth's surface rose 2.2 percent in less than three decades, the researchers report in a study appearing in the journal Nature."
Where this fits into the scheme of AGW is this: water vapor is a GHG, but because it has a short residence time in the atmosphere (on the order of days or perhaps weeks in the troposphere), it is unable to initiate climate change. However, if climate change is initiated by other factors (such as a rise in long-lived GHG concentrations in the atmosphere), then water vapor can amplify the impacts (feedback)--in this specific case, since the air is warmer, the atmosphere can contain more moisture, and if there's more water vapor in the air, that will amplify the day-to-day impacts of climate change.
Here's the AGW website's discussion of water vapor feedback vs. forcing:
http://www.realclimate.org/index.php/archives/2005/04/water-vapour-feedback-or-forcing/
In this, they make a point of noting that the models *predict* that although specific humidity will rise, relative humidity will remain about constant, which is presumably why the authors were sure to note this in their abstract.
Hope this helps clarify :)
In Christ,
Christine
Christine,
Thank you. This is exactly the kind of article that I find so frustrating. To assert that the moisture holding capacity of the air will rise with temperature as a proof of AGW seems to me to be using the known physical nature of air and suddenly attributing it to a new cause. Why is there any surprise at all that warmer air will hold more moisture, whatever the cause of the heat. Moisture capacity is an effect of air temperature. These studies frustrate me becuase they claim a known attribute of warm air - its moisture capacity is proof of a desired cause. They are implying that uniquely the current air moisture content is due to AGW, when they offer no proof of this at all.
Hello again,
My understanding is this:
1) The increase in global specific humidity is evidence that the the air is warmer on average than it used to be. As you note, this fact alone does not show climate change to be human-induced; it only supports the assertion that climate is changing.
2) The authors are stipulating the link to *humans* (+ natural influences) because the observations cannot be explained on the basis of modeling climate with natural factors alone. In order for modeling to fit the observations, human influences must be included. Thus, they are not "using the known physical nature of air and suddenly attributing it to a new cause.", nor are they "surprise[d]...that warmer air will hold more moisture."--they are using observational data and physical laws as a basis to test a variable (human influence) in a model to differentiate between two hypotheses. If the Case B model (human + natural) predicts the observational data but the Case A model (natural only) does not (which is what the authors are saying), then I see only three possibilities: 1) case B is the (primary) cause of the observations 2) the model is deficient in some fundamental manner to the extent that it would change the substance of the conclusions and/or 3) the observational data is deficient in some fundamental manner to the extent that it would change the substance of the conclusions.
As I have not read the study, I cannot speak specifically to the data the authors used in order to evaluate #3--although, given the years studied (beginning in 1979), I find it difficult to believe that our understanding of how to measure humidity was so grievously wrong back then that it would change the substance of the conclusions. From what I've read about climate models, I do not think #2 is true, although I'm not claiming to be a climate model expert by any means. Therefore, I believe that #1 is the most plausible interpretation of the data and the model's results.
I guess I'm still struggling to understand your perspective. The scientific basis of AGW seems very logical to me: GHGs retain heat; humans emit large quantities of GHGs that would not otherwise have been emitted naturally in such a short time period; the atmospheric concentration of GHGs is increasing; more heat is retained; temperatures are increasing on average; humidity is increasing on average. This is obviously a very simplistic way of describing it, but still--Which step(s) in this process do you question, and why? Do you have an alternative explanation that you prefer (I know Bruce mentioned cosmic rays and solar influences--do you share his perspective? If so, could you address some of the questions I posed earlier?)
I appreciate your patience and dialog on this issue. :)
In Christ,
Christine
Hi all,
Here's a link to another BBC article discussing cosmic rays and climate change :)
http://news.bbc.co.uk/2/hi/science/nature/7092655.stm
In Christ,
Christine
Hello again,
It occurred to me that in the previous IPCC links I posted, this one should have been included:
http://ipcc-wg1.ucar.edu/wg1/Comments/wg1-commentAgree.html
This link will allow you access to the comments and responses made to the IPCC report during the review process.
In Christ,
Christine
Hello again,
Not sure if anybody still checks this, but I thought I'd post an article illustrating a new finding on a natural cause of (local) warming being factored into the bigger picture. http://news.yahoo.com/s/livescience/20071213/sc_livescience/magmamaybemeltinggreenlandice Happy reading :)
In Christ,
Christine
thank you for keeping up with this important issue. I very much enjoy and benefit from your perspective on this.
Merry Christmas and a Blessed New Year.
Regards,
Ed
Merry Christmas to all!!!
There is a new book out entitled "Cool It" by Bjorn Lomborg. Lomborg - previously the author the best-selling "The Skeptical Environmentalist's Guide to Global Warming" and named one of Time magazines 100 most influential people in 2004 - does believe that global warming is occurring, but not to the degree, or at the pace, that alarmists like Al Gore would have us to believe. Nor are the consequences all bad - in fact, some are, and will be, very good, not only for our species but for others. The key, Lomborg believes, is to assess the facts and approach whatever problems need to be addressed in a rational way - which means not wasting all our energy and resources on Chicken-Little hysteria when there are more pressing problems facing the world.
"Cool It" gives the facts and documentation behind hundreds of "politically incorrect" revelations like these:
1) Sea levels will rise about one foot over the next century, according to the UN's 2007 IPCC report - the same rise that has occurred since 1860. A 20-foot rise, such as the one seen in "An Inconvenient Truth" is hypothetical at best.
2)Global polar bear populations, contrary to environmentalist's claims, are generally stable, and two populations around the Arctic Sea are actually growing. The most substantial drops in polar bear populations are a result of recreational hunting, not global warming.
3)The recent increase in impact from hurricanes and storms has nothing to do with global warming and everything to do with the rising concentrations of population and infrastructure in coastal areas. The data available today does not support unequivocal claims that global warming is worsening storms.
4) Though such global warming as may actually occur will mean more heat-related deaths - about 40,000 more in the United States in 2050 - there will also be 200,000 fewer cold deaths by then in the U.S.
5) The Kyoto Protocol is both impossible ambitious and environmentally inconsequential. It would cost $180 billion a year for the rest of the century but would only postpone global warming by five years in 2100.
Christine,
I finally had time to review your link and had trouble getting it to work.
Here are some links I am enjoying on the topic right now:
http://icecap.us/images/uploads/Evans-CO2DoesNotCauseGW.pdf
http://science-sepp.blogspot.com/2007/12/press-release-dec-10-2007.html
http://nzclimatescience.net/index.php?option=com_content&task=view&id=155&Itemid=1
Hello all,
Nice to see some new posts :) Merry Christmas to you all too!
I'll answer each post separately, as I haven't yet had time to look at Ed's links (by the way, the links don't appear to work if you copy & paste them directly into the browser...seems you need to put them into a text file or word doc., (retype them?), and then copy & paste them back to the browser)...
Bruce—
To begin, a word on politics…you’ll note that in all my posts, I have not once brought up Al Gore, the Kyoto Protocol, or the Inconvenient Truth…mainly because, none of these form the scientific basis upon which global climate change as a theory has developed. The closest of these to “science” is an Inconvenient Truth, but this only presents one interpretation of the climate change data, and is targeted towards a lay audience at that. As such, I don’t see them as useful for discussion, at least not until we come to some type of agreement regarding the basic merit (or lack thereof) of AGW. Therefore, I would hope that we could move beyond these references in our discussion to a more technical discussion of the science in question.
In that spirit….you cite:
“1) Sea levels will rise about one foot over the next century, according to the UN's 2007 IPCC report - the same rise that has occurred since 1860. A 20-foot rise, such as the one seen in "An Inconvenient Truth" is hypothetical at best.”
It is true that the IPCC report is more conservative in its estimates for sea level rise than others are; as an aside, I believe this is one illustration of a point I made during our discussion at our ASA meeting—that the IPCC, being based on consensus, is more conservative in general, and as such, I think that gives them a certain amount of credibility. Back to the main point though…the estimates for sea level rise were among the most contentious during the development of the IPCC report. Some wanted to include the most recent studies (they had a cut off point of looking at studies in 2005 or 2006 I think), which indicated higher estimates than what they ended up including in the IPCC report.
To expand on the reference given, here is an excerpt from the IPCC report (my apologies for the length). To see the full text, read here: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter5.pdf
IPCC Report: “Global sea level rose by about 120 m during the several millennia that followed the end of the last ice age (approximately 21,000 years ago), and stabilised between 3,000 and 2,000 years ago. Sea level indicators suggest that global sea level did not change significantly from then until the late 19th century. The instrumental record of modern sea level change shows evidence for onset of sea level rise during the 19th century. Estimates for the 20th century show that global average sea level rose at a rate of about 1.7 mm yr–1.
Satellite observations available since the early 1990s provide more accurate sea level data with nearly global coverage. This decade-long satellite altimetry data set shows that since 1993, sea level has been rising at a rate of around 3 mm yr–1, significantly higher than the average during the previous half century. Coastal tide gauge measurements confirm this observation, and indicate that similar rates have occurred in some earlier decades.
In agreement with climate models, satellite data and hydrographic observations show that sea level is not rising uniformly around the world. In some regions, rates are up to several times the global mean rise, while in other regions sea level is falling. Substantial spatial variation in rates of sea level change is also inferred from hydrographic observations. Spatial variability of the rates of sea level rise is mostly due to non-uniform changes in temperature and salinity and related to changes in the ocean circulation.
. . .
Global sea level is projected to rise during the 21st century at a greater rate than during 1961 to 2003. Under the IPCC Special Report on Emission Scenarios (SRES) A1B scenario by the mid-2090s, for instance, global sea level reaches 0.22 to 0.44 m above1990 levels, and is rising at about 4 mm yr–1. As in the past, sea level change in the future will not be geographically uniform, with regional sea level change varying within about ±0.15 m of the mean in a typical model projection. Thermal expansion is projected to contribute more than half of the average rise, but land ice will lose mass increasingly rapidly as the century progresses. An important uncertainty relates to whether discharge of ice from the ice sheets will continue to increase as a consequence of accelerated ice flow, as has been observed in recent years. This would add to the amount of sea level rise, but quantitative projections of how much it would add cannot be made with confidence, owing to limited understanding of the relevant processes.”
Bruce cites:
“2)Global polar bear populations, contrary to environmentalist's claims, are generally stable, and two populations around the Arctic Sea are actually growing. The most substantial drops in polar bear populations are a result of recreational hunting, not global warming.”
The U.S. Fish & Wildlife Service has proposed that the polar bear should be protected as a “threatened” species under the Endangered Species Act; they recently finished receiving public comment on this proposal, and will render a final rule next year. See here for more info.: http://alaska.fws.gov/fisheries/mmm/polarbear/issues.htm.
You will see here that they state the “primary threat to polar bears is the decrease of sea ice coverage.” Further, “generally stable” is misleading, as the polar bear assessment cites the following as just one example of a destabilization in the population (again, I apologize for the length): “Recent studies indicate that polar bear distributions are changing and that these changes are strongly correlated to similar changes in sea ice and the ocean-ice system. Specifically, in Western Hudson Bay, breakup of the annual sea ice now occurs approximately 2.5 weeks earlier than it did 30 years ago (Stirling et al. 1999, p. 299). The earlier spring breakup was highly correlated with dates that female polar bears came ashore (Stirling et al. 1999, p. 299). Declining reproductive rates, subadult survival, and body mass (weights) have resulted from longer periods of fasting on land as a result of the progressively earlier breakup of the sea ice caused by an increase in spring temperatures (Stirling et al. 1999, p. 304; Derocher et al. 2004, p. 165). Stirling et al. (1999, p. 304) reported a significant decline in the condition (weights) of both male and female adult polar bears since the 1980s in Western Hudson Bay, as well as lower natality rates. A positive relationship between body mass of females with cubs and survival of cubs was also established; survival of cubs of mothers in better condition (heavier) was greater than survival of cubs from lighter mothers (Derocher and Stirling 1996, p. 1248). Stirling et al. (1999, p. 304) cautioned that although downward trends in the size of the Western Hudson Bay population had not been detected, if trends in life history parameters continued downward ‘‘they will eventually have a detrimental effect on the ability of the population to sustain itself.’’ Population declines have now been determined based on a recent analysis of an ongoing mark-recapture population study, and the earlier predictions of Stirling et al. (1999; p. 304) have been proven. Between 1987 and 2004, the number of polar bears in the Western Hudson Bay population declined from 1,194 to 935, a reduction of about 22 percent (Regehr et al. in prep.). Progressive declines in the condition and survival of cubs, subadults, and bears 20 years of age and older, likely initiated the decline in the size of the Westen Hudson Bay population; these declines appear to have been initiated by progressively earlier sea ice breakup. Once the population began to decline, existing harvest rates of this population contributed to the reduction in the size of the population (Regehr et al. in prep.).”
Bruce cites:
“3)The recent increase in impact from hurricanes and storms has nothing to do with global warming and everything to do with the rising concentrations of population and infrastructure in coastal areas. The data available today does not support unequivocal claims that global warming is worsening storms.”
I will largely agree with that statement. It is still an unsettled question as to whether or not tropical weather has worsened due to climate change, either in frequency, intensity, or both. And claims to this effect based on monetary losses are indeed misleading. I would also add to this that there are factors to tropical weather development that we are just beginning to understand. Just this morning I read on article describing the cooling effect of Saharan dust and how that seems to have toned down tropical storm development during the 2006 hurricane season. Nevertheless, the hypothesis that warmer ocean temperatures induced by climate change will worsen tropical storm development is a reasonable one. We will just have to wait and see what happens as we gather more data.
Bruce cites:
“4) Though such global warming as may actually occur will mean more heat-related deaths - about 40,000 more in the United States in 2050 - there will also be 200,000 fewer cold deaths by then in the U.S.”
I have heard this as well, and don’t necessarily question its validity (I haven’t really investigated that specific claim). However, there are other factors in play here. For example, warmer climates will likely mean an expansion of the area into which mosquito-born and other climate-dependent illnesses can occur. Likewise, warmer climates will enhance ground-level ozone formation, which has known negative health impacts.
My assessment of the net impacts of climate change is this: yes, there will be some benefits, and yes, there will be some negatives. However, I think the potential negatives are more numerous than the potential benefits. Why? In *principle* I don’t see anything wrong with a changing climate. The problem is the rate of change…at a very fundamental level, human civilization is constructed upon a few assumptions about life, one of which is having a relatively predictable *climate* (as opposed to weather). If, as the models suggest and observations are beginning to bear out, we are to experience a rapid change in climate (on the order of decades rather than centuries or longer), entire societies are going to undergo a great deal of turmoil as we adapt to these changes, and existing problems (such as poverty) will be aggravated. Large scale societal/global turmoil generally is not conducive to strong economies, world peace, and prosperity. We are sinful by nature, and when put under stress (particularly if part of that stress is induced by resource shortages), that nature tends to reveal itself in ugly ways. So although you could in theory, just wait out climate change with an optimistic view that technology will save us or that it won’t be as bad as we think, I don’t think its worth the gamble.
Anyway, my apologies for the very lengthy post…
In Christ,
Christine
Hello again everyone,
Just wanted to quickly post a couple of links:
http://news.bbc.co.uk/2/hi/science/nature/7207335.stm
http://www.agu.org/sci_soc/policy/positions/climate_change2008.shtml
The first link is a BBC story saying that the American Geophysical Union (which, as several of us are geologists, I know we will all be familiar with) had revised its statement on climate change. The second link is the actual revised statement posted on the AGU website.
In Christ,
Christine
Christine,
Thanks for this. I have been following the AGW statement since it was posted. There seems to be a probelm at the AGU, where a committee has asserted that its personal statement of opinion whould speak for the entire AGU.
http://dotearth.blogs.nytimes.com/2008/01/24/earth-scientists-express-rising-concern-over-warming/#comment-8649
Here is the essential problem of AGW, as I see it:
It is not falsifiable.
No matter the weather reality, it is *proof* of AGW.
When you read the comments of the AGW promoters, you read about belief, faith, battling against evil conspiracies. Skeptics, if they are lucky, are only called 'deniers'. Ofthen they are called 'riminals' or 'planet killers'. That is not how people who actually have something real behave. That behavior is a faith-based response. That implies strongly that the underlying belief is faith-based.
When you read skeptics, you read about lack of evidence, inconsistent evidence, bad measurements, lack of precisison, lack of historical context.
That is the normal way science is tested. Here is a revers example:
In evolutionary science, when evolution is challenged, scientists produce evidence. In fact, when scientists do produce evidence, they win.
When AGW is questioned, the questioners are vilified. They are not challenged with eveidence. Instead they are shouted down with a long list of ever changing contradictory claims.
Read the AGU statement. it is ridiculous on its face. It makes claims about the climate that are not known. It claims by implication that there is something un-natural in the climate patterns of today.
That is simply untrue.
Not only is it untrue, it is ridiculously untrue.
Christine,
Thanks for this. I have been following the AGW statement since it was posted. There seems to be a probelm at the AGU, where a committee has asserted that its personal statement of opinion whould speak for the entire AGU.
http://dotearth.blogs.nytimes.com/2008/01/24/earth-scientists-express-rising-concern-over-warming/#comment-8649
Hello all,
Hope all is going well for everyone!
I finally got some time (about 7-8 hours) to sit down and review the links that Ed posted earlier; also wanted to respond to his latest posts as well…
Ed:
I wasn’t able to find the first link you posted directly, but I think I found it by accident through the New Zealand site you pointed to in the third link (never did find what you were pointing to in third link). Is this the one you were looking at in the first link?: http://nzclimatescience.net/images/PDFs/devansco2.pdf
My response to the material presented in this article…first, was this published in a peer-reviewed scientific journal? As far as I can see, it doesn’t appear to have been…second, regarding the “CO2 lag”…yes, it’s true that in geological time, rising temperatures have initiated rises in CO2 levels. The study which they’re referring to (though they don’t reference it) is probably this one: http://icebubbles.ucsd.edu/Publications/CaillonTermIII.pdf) It is well-known that other factors, such as the Milankovich Cycle, can also induce climate change, and that increasing temperatures tend to release naturally stored greenhouse gases from their “sinks” (i.e. the ocean, permafrost, etc.)—AGW proponents do not deny this. However, just because temperature can cause an effect on CO2, it does not follow that CO2 cannot cause (initiate) an effect temperatures. Indeed, it is thought that the greenhouse gas releases in previous climate change episodes enhanced the overall warming effect (and vice-versa—when other changes induced cooling, atmospheric CO2 was reduced and cooling was enhanced). In fact, the very paper they appear to be referencing even mentions this in their closing paragraph: “Finally, the situation at Termination III differs from the recent anthropogenic CO2 increase. As recently noted by Kump (38), we should distinguish between internal influences (such as the deglacial CO2 increase) and external influences (such as the anthropogenic CO2 increase) on the climate system. Although the recent CO2 increase has clearly been imposed first, as a result of anthropogenic activities, it naturally takes, at Termination III, some time for CO2 to outgas from the ocean once it starts to react to a climate change that is first felt in the atmosphere. The sequence of events during this Termination is fully consistent with CO2 participating in the latter _4200 years of the warming. The radiative forcing due to CO2 may serve as an amplifier of initial orbital forcing, which is then further amplified by fast atmospheric feedbacks (39) that are also at work for the present day and future climate.” See also: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter6.pdf (FAQ 6.1), http://gristmill.grist.org/story/2006/12/22/231145/76, http://gristmill.grist.org/story/2006/12/26/224933/67, http://www.realclimate.org/index.php/archives/2004/12/co2-in-ice-cores/. In short—AGW proponents are not arguing against the evidence from ice cores and past geologic periods of warming; rather, we’re arguing on the basis of that evidence that since greenhouse gas concentrations in the past have had a global influence on climate (whether by enhancing or dampening it), human activities that have led to a rise in greenhouse gas concentrations will have a similar effect on the global climate now.
Second—the “hot spot” missing in the tropics. This is an area of active research, and from what I can gather, has still not been entirely resolved yet. Here is realclimate.org’s discussion of it—they believe that the discrepancy is a result of measurement error: http://www.realclimate.org/index.php/archives/2005/08/the-tropical-lapse-rate-quandary/. I confess I don’t have enough technical expertise in this area to more critically assess it myself. However, I strongly question Evan’s statement of: “There is no hotspot in the tropics at 10 km up, so now we know that greenhouse warming is not the (main) cause of global warming — so we know that carbon emissions are not the (main) cause of global warming.” This is a highly simplistic and unwarranted conclusion that seems to assume 1) there could be no other reason for the discrepancy, 2) there’s no other evidence supporting climate change theory, and 3) that this “hotspot” is so fundamental to climate change theory that if something conflicts with the prediction, then the whole theory must be thrown out, which is not true. Additional alarm bells go off in my head when I read this: “Of course, these observations need to be repeated by other researchers before we can be completely sure, but they are made by top-notch researchers and reported in top-of-the-line peer-reviewed journals so at this stage they look solid:” Anyone interested in upholding the integrity of science, that uses data of others to support their ideas without actually citing (or even so much as giving the title and author of) those papers, should have a problem with this statement.
With respect to clouds…predicting clouds and precipitation has always been acknowledged as one of the more complex and uncertain tasks in climate modeling and prediction. For example, the IPCC states here: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter8.pdf that “Significant uncertainties, in particular, are associated with the representation of clouds, and in the resulting cloud responses to climate change. Consequently, models continue to display a substantial range of global temperature change in response to specified greenhouse gas forcing (see Chapter 10). Despite such uncertainties, however, models are unanimous in their prediction of substantial climate warming under greenhouse gas increases…” They further state that “8.6.3.2.2 Interpretation of the range of cloud feedbacks among climate models: In doubled atmospheric CO2 equilibrium experiments performed by mixed-layer ocean-atmosphere models as well as in transient climate change integrations performed by fully coupled ocean-atmosphere models, models exhibit a large range of global cloud feedbacks, with roughly half of the climate models predicting a more negative CRF [cloud radiative forcing] in response to global warming, and half predicting the opposite (Soden and Held, 2006; Webb et al., 2006).” Beginning on page 635 in Chapter 8 (see link referenced above), they have an extensive discussion on Clouds and the role they play in the modeling. I think it is unfair for Evans to characterize the IPCC’s assumptions so simplistically; nevertheless, even if he were right, it only lessens the extent to which global climate change occurs—it does nothing to undermine the scientific merit of the theory. As an aside, Evans again casually states that, “In September 2007 he [Roy Spencer] reported that in reality warming is associated with fewer high clouds.” Really? Where did he report this? Again, no references…
With respect to “Warming is Waning”…Evans first states that “The only temperature data we can trust are satellite measurements, and they only go back to 1979. (Ground-station data is corrupted by an unknown amount of urban heat island effect.)”. This is absolutely wrong. First off, “temperature data” does not only include direct measurement via a thermometer, it also encompasses proxy data such as historical descriptions of weather events, ice core and tree ring data, etc. Secondly, scientific studies at present show that the urban heat island effect (UHI) has a negligible impact on the temperature record. See: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter3.pdf (beginning on page 243), http://www.realclimate.org/index.php/archives/2004/12/the-surface-temperature-record-and-the-urban-heat-island/, http://gristmill.grist.org/story/2006/10/31/15216/865, and http://gristmill.grist.org/story/2006/10/26/224634/48. Evans goes on to state that “Satellite temperature data shows that there has been no warming in the southern hemisphere, and that the warming trend in the northern hemisphere has waned since 2001:” Apparently, the author was unaware, or chose not to address, issues relating to adjustments and error. See: http://www.realclimate.org/index.php?p=170. The IPCC also covers this in Chapter 3 (referenced in an earlier link).
With respect to your second link (Singer’s press release)….I was not able to find or get access to the actual study being referenced…the closest I could come was the abstract posted on the International Journal of Climatology website: http://www3.interscience.wiley.com/cgi-bin/abstract/117857349/ABSTRACT. So, I can’t critique the actual paper. Here is the extensive discussion of it on realclimate.org: http://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends/. Aside from the study itself, I would point out one thing regarding the press release. They state that: “These results [from their study] are in conflict with the conclusions of the United Nations Intergovernmental Panel on Climate Change (IPCC) and also with some recent research publications based on essentially the same data. However, they are supported by the results of the US-sponsored Climate Change Science Program (CCSP).”
However, if you actually go to the CCSP website (see here: http://www.climatescience.gov/Library/pressreleases/pressrelease16feb2007.htm), you will see the following: “CCSP assessment activities significantly contributed to the IPCC’s increased confidence attributing much of the temperature increase since the mid-20th century to human activities. . . “CCSP participates in and accepts the findings of the IPCC,” said Dr. William Brennan, acting director of CCSP. “Through the focused efforts of the CCSP, we are making true breakthroughs in our understanding of how our planet’s climate is continuing to change, and there is no better example than our program’s contribution to the latest IPCC report which strongly links humans to climate change,” said Dr. Brennan.”
At best, it seems to me that the press release is highly misleading by stating that the CCSP agrees with their conclusions.
Now, to your more recent posts. You refer to questions being raised about the AGU’s revised statement on climate change by linking to this blog: http://dotearth.blogs.nytimes.com/2008/01/24/earth-scientists-express-rising-concern-over-warming/ where a Senate staffer stated (in part) the following: “It appears that the AGU Board issued a statement on climate change without putting it to a vote of the group’s more than 50,000 members. Its sweeping claims were drafted by what appears to be only nine AGU committee members. . . Bottom line, this new AGU statement appears to in no way represent the views of the AGU rank-and-file members.”
I strongly disagree with the concept behind this statement. Anyone who understands the democratic process will realize that you will never have 100% of the people in your organization fully in agreement with the leadership of that organization. Nevertheless, in the words of a commenter on the blog who is an AGU Fellow: “As an AGU member (Fellow, in fact) I fully endorse the AGU statement on global warming. I am not a member of the council, and had no role in writing this statement myself. In response to Mr. Morano, I’ll echo one of the other commenters in pointing out that AGU is a democracy, and the officers are elected by vote of the entire membership. If any significant part of the leadership were notably out of tune with the membership, they would be voted out of office pretty swiftly, or would never have risen to the posts they have. To deny the significance of this statement on the grounds that it is a product of the council is like denying the legitimacy of US law because we have a representative democracy.”
Or in our context: Is every instance in which Randy Isaac (Exec. Director of ASA) and/or the ASA council speak just merely their own personal opinion, having no mandate or authority to speak on behalf of the larger ASA organization? I don’t think so.
Moving on to your last post….you write:
“Here is the essential problem of AGW, as I see it: It is not falsifiable. No matter the weather reality, it is *proof* of AGW.”
First point—weather does not equal climate. Weather describes the short-term meteorological characteristics of a place—i.e. it is sunny and 76 degrees today. Climate describes the long-term statistical trends and patterns associated with a particular locale—i.e. On average, summer highs in Houston are about 95 degrees and rainfall is approximately 10 inches (or whatever it is in reality—I just made up those numbers). In other words, if you were flipping a coin, “climate” says that about 50% of the time you’ll get heads and about 50% of the time you’ll get tails; “weather” says that on one particular toss, you got tails. Thus, the “weather reality” (of a particular day, place, or time) has nothing to do with “proving” AGW.
Second point—AGW is falsifiable. AGW as a scientific theory states that human activities are generating an increase in atmospheric greenhouse gas concentrations, and that these activities will change the global climate (and that *overall* the change will be that the earth will warm). There are three points of potential falsification 1) you could show that human activities are not increasing atmospheric greenhouse gas concentrations, 2) you could show that the increase in greenhouse gases will not result in climate change, and 3) you could show that the overall change of the global climate will not be warming. None of these are beyond the ability of science to speak to (in other words, they’re not metaphysical/philosophical questions) nor are the beyond the ability of current science to actually measure (we have the technology and scientific understanding to address the questions).
Ed writes:
“When you read the comments of the AGW promoters, you read about belief, faith, battling against evil conspiracies. Skeptics, if they are lucky, are only called 'deniers'. Ofthen they are called 'riminals' or 'planet killers'. That is not how people who actually have something real behave. That behavior is a faith-based response. That implies strongly that the underlying belief is faith-based.
When you read skeptics, you read about lack of evidence, inconsistent evidence, bad measurements, lack of precisison, lack of historical context.
That is the normal way science is tested.”
I strongly disagree with what you write here in a number of ways.
First—I am an “AGW promoter”—please point out to me in what way I have denigrated my opponents or spoken of “evil conspiracies”. Likewise, the IPCC report is the authoritative document on global climate change—please point out specifically where in that report they denigrate their opponents or speak of “evil conspiracies”. Please show me how I or the IPCC or any of the posts I have linked to have neglected evidence, measurements, uncertainties, or the history of the issue. In contrast, on this very blog, AGW proponents have been described as “alarmists” who display “chicken-little hysteria”; implicitly, they were characterized as irrational and politically correct to the detriment of the truth. In previous posts, you have described your *beliefs* that AGW is “thin science” based on a list of “self-referential conclusions” that is more of a “fundamental religion” than a science. You have described your “frustration” about studies showing “no proof at all”, and then you state that the AGU statement is “not only untrue, it is ridiculously untrue.” Yet what evidence, what scientific studies, what specific data have you and others cited to back these claim up or contradict the information that I have presented? What alternative theories have you articulated? How many of the questions that I raised did you and others address? The only items approaching actual science that we have dialogued on are 1) cosmic rays, 2) humidity, 3) the links I just addressed in this post, and much more briefly: polar bears, hurricanes, human impacts, and sea level. I ask you, based on a reading of this blog, who has been more engaged with the science: “AGW promoters” or the “skeptics”? I write all of this, not because I want to turn this into an “us versus them” debate, but only to demonstrate that I think your characterization of “AGW promoters” is very unfair. While pointing out the splinter in other’s eyes, let us not neglect the log in our own.
Second….I take issue with your usage of the word “faith” here. Although on a secular blog, we may forgive the careless usage of the word given the context, I feel obliged to point out that we are posting on a Christian blog, and the word “faith” carries with it connotations and meanings that directly relate to our claims about Christ. I find it highly disturbing that you equate a “faith-based response” to an uncharitable defense of an empty claim (or what you believe is an empty claim). The kind of defensiveness and spitefulness you describe can be true of any person defending any claim, with or without evidence…it is a completely emotional and immature reaction on the part of a person who has no interest in a loving, constructive dialogue. Likewise, you imply that a “faith-based” claim is empty—but as a people of faith, and particularly as a people of faith dialoguing in science, we hold that faith can be both rational and represent a truthful claim of reality. Faith does not equal empty or untrue.
Third, I would also point out that fundamentally, science is faith-based. Faith-based in the sense that there are certain axioms that scientists must accept in order to claim that science itself has any meaning or reality. To paraphrase David O. on the ASA listserv, reason itself requires a belief/faith in its own credibility that cannot be proven by reason. On a more practical level, even as we operate with a healthy (and necessary) skepticism within science, we must also have a certain amount of faith that in disciplines and fields that are not our own, we can trust the veracity of their conclusions—otherwise, for example, I would not be able to trust that humans descended from primates or that smoking causes lung cancer, because I haven’t analyzed all the relevant studies personally and become an expert in those fields.
Fourth, raising questions about “lack of evidence, inconsistent evidence, bad measurements, lack of precisison, lack of historical context.” is only part of the way that “science is tested”. It would be more complete and more true to the scientific method to say that hypotheses are tested by running an experiment in which you hold everything else constant (control), alter one parameter (variable), and then see which outcome better fits your hypothesis (model). The normal way of testing science is not merely raising questions about the results of others (reactive), it is also proactive (constructing your own models and gathering your own data). And of course, science also relies upon (has faith in) the integrity of the scientist conducting the research and/or raising the questions. Simply collecting data or simply questioning a conclusion doesn’t constitute science unless it is done in a manner that is honest and (as much as possible) unbiased.
Finally, you write:
“Read the AGU statement. it is ridiculous on its face. It makes claims about the climate that are not known. It claims by implication that there is something un-natural in the climate patterns of today.
That is simply untrue.
Not only is it untrue, it is ridiculously untrue.”
I have read the AGU statement. Much of the material is drawn from the IPCC report, some of which I have also read and referenced in our discussions here. Which claims do you specifically believe are “not known”, and why? Why do you believe that it is unreasonable or untrue to claim that humans have anything to do with it? Even if this statement represented the opinion only of the AGU council (which it doesn’t), on what basis do you feel its warranted to characterize their conclusions as “ridiculously untrue” given their experience and position? Please note on this last question, that I am not saying that it is wrong or unwarranted to question someone who is more experienced and/or is in a higher position of authority than yourself; rather, I think it is incumbent on the challenger to (at a minimum) provide a justification for the claim.
To wrap-up, I leave you with the words of Loren Haarsma from the ASA listserv—he was speaking in more general terms and more within the context of the evolution debate, but I think his words apply equally well here, and are a good reminder to ALL of us:
“There is often the sin of pride. If you are aware that your claim is outside the consensus of most experts, it ought to make you humble and cautious in your claims, not proudly proclaiming that you and your small group are obviously right and the consensus of experts is obviously both wrong and stupid.
Real harm comes to people who hear the pseudoscience repeated, since this can hinder them from ultimately getting at the truth. (And in the case of medical quackery, it can cause real physical harm to people.)
Real harm comes to the good reputation hard-working experts whose consensus opinion is discarded whenever pseudoscience claims are accompanied (as they often are) by the claim that those experts are all stupid, biased, immoral, or all of the above.
Real harm comes to the cause for which the pseudoscience is being advanced. Those who hear the pseudoscience and recognize it as pseudoscience will be prone to think badly of the cause behind it. It is a terrible shame when the cause being hurt this way is the gospel of Christ and the church.”
May we continue to dialogue in truth and love, seeking to uphold both the integrity of science and of our Christian faith…
In Christ,
Christine
Christine,
Please accept my thanks for your very thoughtful and thought provoking answer. I have read it earlier today, and have been considering it all day. I am very busy this day, and will answer you properly as soon as time permits.
I appreciate your care and thoroughness greatly.
Hi all,
Ed--thanks for your reply...I look forward to your response when you get the time :)
In the meantime, this came across the ASA listserv from Randy Isaac...thought it might of interest :)
In Christ,
Christine
"One of the symposia I was able to attend at the AAAS meeting was on the study of the ocean for insight into historical patterns of global climate. The two papers I heard were by Jim Zachos from U. Cal-Santa Cruz and Mark Pagani from Yale.
Here are a few tidbits I gleaned that I thought were interesting.
1. Ocean surface concentrations of the isotopic ratio C-13/C-12 can be reconstructed historically from corals and forams. The data obtained in this way correlate well with atmospheric data reconstructed from trees. The data over the past millenium show a constant ratio until the mid 19th century at which point the ratio drops rapidly to its present level. That reduction can be traced to the release of carbon from fossil fuels which have approximately 60% lower C-13/C-12 ratio than current atmospheric levels. In other words, the carbon-13 ratio provides conclusive evidence that the rise in atmospheric carbon dioxide concentration since the mid-19th century is due to anthropogenic burning of fossil fuels.
2. The symposium focused on detailed analyses of the climate over the last 65 million years as deduced from oceanic data. The time from now to 35Mya is dubbed the icehouse era while 35-65Mya is the hothouse era. The carbon levels were also much higher in that hothouse era.
In the hothouse era there is a fascinating dip in temperature at the Paleocene-Eocene transition at 55Mya. The global temperature peaked at 52Mya at around 8C warmer than today. But at the 55Mya mark there is a sharp dip and recovery of around 3C. A very careful study of fossils around that time frame allowed them to correlate the carbon concentration and the temperature. The rate of the transition is definitely less than 4,000 years and could be less than 1,000 years. More study of this dip and recovery would be of considerable interest in understanding how fast the earth responds.
At the peak temperature at 52Mya, there was no freezing temperature at the North Pole and that's when the swamps and vegetation thrived in that area, ultimately becoming the oil fields now of interest. There was no ice on the earth (in marked contrast to around 600 Mya or so when it was all ice!). The Antarctica ice formation happened at the hothouse/icehouse transition at 35 Mya. Pagani reported that a very thorough study had cleared up discrepancies in the carbon data and that the resulting data showed a steep gradient of carbon concentration that matched the temperature change very well at that transition.
Although I couldn't follow all the details, they also stated that during this "icehouse" period, there had been a lot of bewilderment about how the temperatures and carbon levels correlated but that these were now better understood and consistent with a 3C/doubling of carbon concentration.
Finally, they noted that around 5 Mya there was a period when the atmospheric carbon dioxide concentration was around 400--about what it is now. At that time the global temperature was 3C higher than today and the sealevel was 25 meters higher. Although some parameters may be different, this is a reasonably good estimate of what the equilibrium temperature and sealevel might be for today's carbon concentration. In fact, we might say that this much temperature rise is baked into the system. We just don't know how long it will take to get there. That is a critical parameter since the urgency and the impact depend very much on the rate of transition.
Several of you have commented that your remaining hesitance about global warming has been the uncertainty of the global climate computer modeling. In this analysis from the oceans, no such complex models are used. The C-13 data clearly nails the origin of the carbon increase and the historical data give good indication of the equilibrium temperature and sealevels. What remains is the time scale for reaching equilibrium. The models are focused on doing that. The fossil records in the oceans do indicate, especially at the Paleocene-Eocene transition--that the response of the earth can be quite rapid, though precision cannot get into the range of a hundred years.
Randy"
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