Arguments
Recent Comments
Prev 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 Next
Comments 119101 to 119150:
-
Argus at 02:35 AM on 19 May 2010Species extinctions happening before our eyes
#64 Ned, My apologies! I should have phrased my remark differently (or withheld it). My native language is not English, so maybe that made it come out even worse. But looking through the 100+ different topics or posts, I have a hard time finding one that is not based on the effects of an increasing percentage of CO2 in the atmosphere. But as you point out, that is the subject of this website (for which I am grateful). -
Phila at 01:54 AM on 19 May 2010Species extinctions happening before our eyes
#58 "Some of the science is over my head, but I appreciate and enjoy reading it never the less." When science is over my head, as it often is, I refrain from assuming that it's the scientists who are getting things wrong. I assume there's a failure of understanding on my part, not theirs. "Oh well LOL" isn't a coherent counterargument. "the author stated that he didn't consider Australia a continent, but an island." Australia is normally considered to be a continent, in both geological and geographical terms. The author you cite seems to calling it an island in order to discard inconvenient data. That should raise some red flags, I think. -
Steve L at 01:53 AM on 19 May 2010The significance of the CO2 lag
The data in 1b do not look linearly related to me. -
Spencer Weart at 00:48 AM on 19 May 2010The significance of the CO2 lag
Full citation is Scheffer et al., Geophys. Res. Lett.,33,L10702,doi:10.1029/2005GL025044,2006 online here -
VoxRat at 00:41 AM on 19 May 2010The significance of the CO2 lag
WAG: What's the one exception? -
WAG at 00:25 AM on 19 May 2010The significance of the CO2 lag
The real problem with this argument is that it is simply illogical. Just because CO2 lags temperature does not prima fascia rule out the possibility that CO2 can also cause temperature to increase. That's the beauty of global warming skeptics - of all the skeptic arguments, all of them except for one are not just scientifically wrong: they are simply logical fallacies. -
Ned at 00:18 AM on 19 May 2010Species extinctions happening before our eyes
Argus writes: [...] whereas this site blames everything on CO2 [...] Please let's be careful in our use of language. Yes, the article at the top of this thread focuses on climate change and doesn't discuss land use, invasive species, or other non-climate stresses on species. But I don't think anyone here is ignorant of or dismissive of the effects of those stresses. We mostly talk about climate change here because that's the subject of the website. Certainly, invasive species and land use change will exacerbate the problems of climate change for many species. -
Argus at 23:55 PM on 18 May 2010Species extinctions happening before our eyes
Thank you, Tom Dayton (#35) for the comprehensive and patient answer. I have also listened to the radio program, where they spent around 10 minutes on the problem, so I now have a much better understanding of the lizard problem. It seemed that, apart from endless presentations over and over again of all the titles of the professors present, most of the podcast was about other problems affecting flora and fauna than AGW, such as drought, urban development, and farming (whereas this site blames everything on CO2). Interesting aspects. Actually two listeners, calling, seemed to have interesting questions that promised to shed even more light on the topic of extinction, but they were cut off before they were allowed to get to the point (and falsely promised to be back after 'the break'). Disappointing practise! -
Ned at 23:51 PM on 18 May 2010The significance of the CO2 lag
Mythago, the details of this are very complicated, but the big picture isn't too bad. There is an equilibrium between CO2 in the atmosphere and CO2 in the ocean that shifts as a function of temperature. If you kept the total CO2 in the system constant but heated the ocean, CO2 would move from the ocean to the atmosphere (if you cooled the ocean, the opposite would happen). But we're not keeping CO2 constant, we're adding CO2 to the atmosphere at a rapid rate. This pushes it higher than the equilibrium value, so some of it gets taken up by the ocean (see below for references). But as it gets warmer, less gets taken up by the ocean than would happen if it were cooler. So, when CO2 was only a feedback rather than a forcing, the ocean would behave as described in the first paragraph of the article at the top of this thread (giving off CO2 when the ocean warmed). But now that CO2 is both a feedback and forcing, the ocean is "forced" to take up some CO2 even though it's warming, because there's so much going directly into the atmosphere. The other complicating factor here is the slow mixing time of the deep ocean. Originally (pre-1970s) most people weren't concerned about AGW because it was assumed that the deep oceans would take up more CO2 than we could ever emit. But from the 1950s to the 1970s evidence began to accumulate that this was incorrect. Because the surface layer takes a long time to mix with the deep ocean, the surface layer becomes saturated with CO2 much more rapidly, and its uptake is limited. Both of these factors mean that if you add a lot of CO2 to the atmosphere, the following chain of events will occur: (1) CO2 very rapidly increases in the atmosphere. (2) CO2 rapidly increases in the surface ocean, leading to a decrease in pH. (3) Because of (1), the atmosphere and surface ocean warm. (4) Because of (3), the surface ocean takes up less CO2, leading to a further increase in (1). (5) On long time scales (centuries to millennia) the CO2, warming, and low pH signal all propagate slowly into the deep ocean. Once you stop adding CO2 to the atmosphere, the following occur: (6) The atmosphere and surface ocean fairly rapidly come into equilibrium. (7) CO2 and temperature of the atmosphere and surface ocean very slowly decrease, and pH correspondingly slowly begins to return to normal. (8) The long memory of the deep ocean spreads out the process of returning to normal conditions over a timescale of millennia. A couple of useful papers (taken from our list here): Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans (Takahashi et al. 2009) The Oceanic Sink for Anthropogenic CO2 (Sabine et al. 2004) I hope this helps. It is indeed a very confusing subject. When I was in grad school in the 1990s we had a lecture & lab exercise on ocean/atmosphere CO2 exchange and the oceanic carbon cycle, and we had to reprise them twice over because the professor (former director of a world-class climate science research institute) kept discovering essential details that he'd left out of the previous, simpler version. All of us students had nightmares about that part of the course! -
JMurphy at 23:39 PM on 18 May 2010Species extinctions happening before our eyes
nofreewind, you state that some of the science is over your head but also that you don't believe that "a one to two degree change in temperature, from 92 to 94F say, is wiping out these lizards" because it doesn't make "common sense" to you. This would suggest that the science behind this particular thread is not over your head, i.e. you understand it and have come to the decision that it is wrong. But when you also say it doesn't make 'common sense' to you, that suggests that your view isn't based on the science but on, rather, something else - this 'common sense'. Could you provide the science you have used to determine your view or state what the 'common sense' is ? -
Arkadiusz Semczyszak at 23:24 PM on 18 May 2010Species extinctions happening before our eyes
With many of the speeches on abrupt climate change - short and long past - the survivors now living species (not only lizards) - I chose two, but one author: Richard Seager ... - "The Little Ice Age" (film): "In the early 14th century cooled off in just 10 years. The temperature was about 2 degrees lower than today. Change in solar activity was low and we need to find out why it had so great influence on the climate. " - in presentation to the New York Academy of Sciences: "These abrupt changes - the Dansgaard-Oeschger events of the last ice age and the Younger Dryas cold reversal of the last deglaciation - are well recorded in the Greenland ice core and Europe and involved changes in winter temperature of as much as thirty degrees C!" -
michael sweet at 23:07 PM on 18 May 2010The significance of the CO2 lag
Mythago: The answer to your question is that in the past the temperature was forced (changed) by some other cause (like solar variation). CO2 was released by the ocean as temperatures increased. In the current situation, CO2 is being released by humans. This CO2 causes (forces)the temperature to rise. The ocean absorbs CO2 from the atmosphere now, changing ocean pH (and decreasing temperature rise). It is not yet known how long the oceans will continue to absorb CO2, or how much will be absorbed. Because the change in temperature is caused by a different forcing, the CO2 response (release, absorbtion) in the ocean is different. The CO2 lead/lag is also caused by the difference in the forcing. -
Ned at 22:58 PM on 18 May 2010Species extinctions happening before our eyes
nofreewind writes: This is the only blog that I would bother to read regarding the warmers point of view. Some of the science is over my head, but I appreciate and enjoy reading it never the less. I'm not sure what a "warmer" is. But if you like this site, you might also check out the thread about Science of Doom. I just added a comment that lists a few other useful and less well known climate science blogs. -
Ned at 22:51 PM on 18 May 2010Woody Guthrie award to The Science of Doom
I too am a fan of the Science of Doom blog. For those who are interested, here are a few more climate science related websites that I like. I'm omitting ones that are already widely known (RealClimate, Tamino) and those that focus more on policy, politics, etc., in favor of less-well-known sites that focus on the data and the science: Climate Change (Chris Colose's blog) Climate Charts & Graphs (Kelly O'Day's blog) The Whiteboard (Ron Broberg's blog) moyhu (Nick Barnes's blog) Clear Climate Code I would add these to the list of links, but that seems to be more intended for people to submit their own blogs as links ... -
Tom Dayton at 22:43 PM on 18 May 2010Species extinctions happening before our eyes
Nofreewind, the Science article that this post is about, is behind a paywall. But a huge number of libraries have that journal. If you're unwilling to get to a copy of the journal, you should at least listen to the radio interview I linked to in my earlier comment. As John explained in his post, the lizards can't forage sufficiently while they are sitting quietly in the shade. Also, they can't find mates. -
Ned at 22:23 PM on 18 May 2010CO2 measurements are suspect
Okay, one last comment. I wrote "Of course, the trends are actually increasing exponentially, but over short periods of time they don't diverge much from a linear trend." To be precise, the CO2 curves are actually increasing faster than an exponential trend. -
Ned at 22:18 PM on 18 May 2010CO2 measurements are suspect
FYI, here are the linear trends in CO2 concentration, 1990-2008, at the stations shown in the above graph:
Of course, the trends are actually increasing exponentially, but over short periods of time they don't diverge much from a linear trend. There are lots of additional stations all over the world that show the same thing. Anyone who still claims that the Keeling Curve is somehow contaminated by proximity to a volcano and unrepresentative of the rest of the world needs to explain why every other non-urban site shows the same pattern.Mauna Loa, Hawaii: +1.79 ppmv/year Barrow, Alaska: +1.78 Cape Ferguson, Australia: +1.79 Halley Bay, Antarctica: +1.78 Key Biscayne, Florida: +1.78 Ocean Station M, Norway: +1.78 Niwot Ridge, Colorado: +1.79 -
Ned at 22:00 PM on 18 May 2010CO2 measurements are suspect
As Tom Dayton suggests, if the question is whether CO2 has a short residence time, that should be discussed in the thread CO2 has a short residence time. If anyone is still uncertain about how consistent CO2 measurements are globally, please go to the World Data Center for Greenhouse Gases, search for CO2 data from various stations, and look at them yourself. Here are some examples of graphs. These data haven't been "normalized" or "fixed" to match each other; they're completely independent data sets. Some are from the polar regions, some from the tropics, some from the northern hemisphere, some from the southern, some from ocean sites, and some from inland sites.
[BW 2015-08-22 - link to graphic on imageshack (co2stnsfull.png) no longer valid]
Here's an enlargement showing 1990 to the present:
[BW 2015-08-22 - link to graphic on imageshack (co2stnspost1990.png) no longer valid]
Note how consistent the following are: the actual value, the upward trend, and the seasonal cycle.
Moderator Response:[BW 2015-08-22 - embedded graphics deleted as no longer showing valid content (were showing advertisments instead) and were breaking page formatting]
-
nofreewind at 21:59 PM on 18 May 2010Species extinctions happening before our eyes
Quokka: >There is only so much WUWT I can take in one sitting. I could say the same about here, but I won't. This is the only blog that I would bother to read regarding the warmers point of view. Some of the science is over my head, but I appreciate and enjoy reading it never the less. But when I see the majority of you completely accept the premise that global warming in Mexico is making these lizards go locally extinct, what I can say but Oh Well, LOL. You mean, that a one to two degree change in temperature, from 92 to 94F say, is wiping out these lizards, I am supposed to believe that is the conclusion?? Sorry, but it just doesn't make any what I call, "common sense" to me. Could someone point me in the direction of the Mexico temperature data. -
nofreewind at 21:54 PM on 18 May 2010Species extinctions happening before our eyes
Quokka: >I didn't get past the abstract. the author stated that he didn't consider Australia a continent, but an island. -
Arkadiusz Semczyszak at 21:46 PM on 18 May 2010Species extinctions happening before our eyes
and ... "... and continually hark back to 12 year old papers ..." - The UNEP Climate Change Science Compendium 2009, on page 5, first version ... -
neilrieck at 21:33 PM on 18 May 2010The significance of the CO2 lag
During previous interglacial periods, natural warming (initially caused by Milankovitch Cycles) cause the oceans to release CO2 into the atmosphere. Milankovitch Cycles are base upon sine-waves but feedback processes (from CO2, water vapor, albedo, etc) change the sine-waves into a resultant saw-tooth wave. See the second graphic on this page: www.southwestclimatechange.org/climate/global/past-present The problem with the current interglacial (which started 11,700 years ago) is that industrial humans have precharged the atmosphere with industrial CO2. As the oceans continue to warm, dissolved CO2 will fizz out then add to the CO2 we have already released. Humanity will be hit with a double whammy. Scientists "have speculated" that our oceans hold 50 CO2 molecules for every CO2 molecule in the atmosphere. Let's hope the warming oceans are able to retain some of it. -
sleepership at 21:22 PM on 18 May 2010The significance of the CO2 lag
So what does this mean in our present time frame? In the current decade- 2010-2020? Would we see a global rise of around .3 degree F? Most climate models see this decade warming as much as the period of 1970-2010. -
boba10960 at 21:21 PM on 18 May 2010The significance of the CO2 lag
John, Thanks for reminding everyone that CO served as a feedback in past climate change and therefore MUST follow the initial climate forcing (e.g., the warming at the end of an ice age). However, temperature is not the main factor causing CO2 to change. The temperature dependence of CO2 solubility in seawater is well known. On glacial time scales the combined effects of changes in the temperature and salinity of seawater could have accounted for only about a fifth of the observed changes in atmospheric CO2 (e.g., W.S. Broecker, Glacial to interglacial changes in ocean chemistry, Progress in Oceanography 2(1982) 151-197). Over the time period covered by the ice core CO2 record the primary factors regulating atmospheric CO2 involved changes in ocean and atmospheric circulation that determine the amount of CO2 stored in the deep ocean, as shown by a number of recent studies. See for example: Anderson et al., Science 323(2009) 1443-1448, and the related Perspective by Toggweiler (same issue, p. 1434). Skinner et al., to appear in Science next week, and the related perspective. George Denton and coworkers have a review (in press) in Science that documents the complete sequence of conditions and events at the end of the last ice age, including the ocean and atmospheric processes that caused CO2 to rise. They emphasize and the importance of CO2 as a feedback to complete the termination of the last ice age. The science is certainly not settled on this issue, and competing hypotheses warrant further examination. But it’s an exciting time to see so many new insights concerning the links between past climate change and CO2. -
Arkadiusz Semczyszak at 21:17 PM on 18 May 2010Species extinctions happening before our eyes
# 50 Chris NOAA Paleoclimatology: "Imagine that over the course of a decade or two, the long, snowy winters of northern New England were replaced by the milder winters of a place like Washington, D.C. Or that a sharp decrease in rainfall turned the short-grass prairie of the western Great Plains into a desert landscape like you would see in Arizona. Changes of this sort would obviously have important impacts on humans, affecting the crops we grow, the availability of water, and our energy usage. These scenarios are not science fiction. Paleoclimate records indicate that climate changes of this size and speed have occurred at many times in the past. Past human civilizations were sometimes successful in adapting to the climate changes and at other times they were not. Because they occur relatively rapidly, these sorts of climate change are called abrupt climate change. Our understanding of past abrupt climate changes and their causes is still in its infancy; most of the research on this topic has been completed since the early 1990s. Scientists have made significant progress, however, in identifying and describing various abrupt events of the past and forming hypotheses about their causes. This paleo perspective will describe the evidence for past abrupt climate change and explore some of the possible causes." (2004,2008) - sorry for so long a quotation -
Mythago at 20:23 PM on 18 May 2010The significance of the CO2 lag
Okay I almost fully understand the principles of CO2 temperature lag but there is still another aspect which suddenly doesn't seem to fit, unless it is an effect that occurs during the time lag period which still doesn't seem to fit. I am referring to Ocean acidification which is (stating the obvious I know) the absorption of CO2. Now you say that the oceans releases CO2 as the temperature rises(first paragraph). So where does CO2 get absorbed into the oceans in this great cycle of events to bring about all this acidification that the oceanographers are screaming about? Are they simply getting jealous about the atmospheric scientists getting all the publicity? :-0) Only joking honest! I know acidification does destroy coral reefs but there seems to be a contradiction here. Has anyone done any research as to this aspect other than to say 'oceans get more acidic and this leads to the destruction of corals etc'? It happens to be a very pertinent point which if a mere amateur like me can spot it then I am sure the idiots who insist its all a scam will no doubt have spotted it too and be busy refuting climate science as another excuse to increase taxes (well here in the UK at least). So can you point me in the direction of some very simple research that will allow me to get my head around that sequence of events so that I can then set the record straight if anyone starts arguing the point. Specifically how CO2 gets absorbed by the oceans, yet is released by the oceans when the temperature increases. Yet there is a temperature lag from increased CO2 in the atmosphere, but the oceans are getting more acidic as atmospheric CO2 increases. But the increased atmospheric CO2 increases atmospheric temperature which increases ocean emissions of CO2. Which surely must reducer oceanic CO2 concentrations which must in turn reduce the acidification unless there is something that I have missed which says that CO2 is absorbed by the oceans from some other third party source. But which source would that be or by which mechanism does this occur? Its one of those silly niggling points that will bug me all day now.:-0) Any help with that would be very gratefully appreciated. -
Arkadiusz Semczyszak at 20:15 PM on 18 May 2010The significance of the CO2 lag
"However, this is complicated by the fact that different carbon cycle processes operate on different time scales." ... and it is very important: the essence - the heart of the matter. There is a huge range of uncertainty as "... Carbon Cycle Processes Operate On Different time scales ..." react (respond) to the temperature rise. For example, land. 11 the computer models, gave for 2,100 years (as projected in different p.CO2 for 2100 - 730 - 1020 ppm) results differ by up to circa 20 GtC/yr ! (Fig 1. (e), (f) - Climate–Carbon Cycle Feedback Analysis: Results from the C4MIP Model Intercomparison, Friedlingstein P. et al., 2006). # 2. MarkR It would be worth on this issue, once again to discuss (on this website) Segalstad's these words: "The IPCC postulates an atmospheric doubling of CO2, meaning that the oceans would need to receive 50 times more CO2 to obtain chemical equilibrium ..." According to me about the amount of CO2 in the atmosphere does not decide the ocean. That soil. I am currently working hypothesis - the scheme: the beginning of warming = increase soil respiration = increase of CO2 in the atmosphere. Remember that, with the highest content of soil humus, there are a temperate climate - warmer version (ie 4% of northern Ukraine, southern 7% humus in the soil). There synthesizing microbes humic acids dominate. The proposal - in the long term warming stimulates the synthesis of humus. Warming (especially tundra) = first increases respiration (p.CO2 increase in the atmosphere), then the succession of microbial groups, biocoenoses synthesize humus (final result: taiga) = increase in humus content = decrease of CO2 in the atmosphere. Delay (tens of years), is due to the fact that there is no simultaneous microbial succession of the whole team. Different species move at different speeds with the progressive warming. I recommend a very interesting publication: Temperature-associated increases in the global soil respiration record. Bond-Lamberty B, Thomson A, Nature. 2010. -
chris at 20:08 PM on 18 May 2010The significance of the CO2 lag
This paper should also be included in this discussion. Like Scheffer et al, Frank et al (2010) analyse pre-industrial Holocone temperature/CO2 relationships to extract a range of likely [CO2] feedback response to temperature change. They consider high values to be rather unlikely. So probably not quite so scary as the numbers in the top article might imply tadzio! That's not to say that there won't be nasty surprises ahead, since these analyses are for relatively non-perturbed natural environments, and unexpected responses to rapid temperature increases might push us into new regimes where theses analyses don't apply (e.g. heat-stressed rain forest die-back and the accompanying loss of carbon sequestration)..... Also it would be good if we would stop cutting down rainforest.... -
Ned at 19:45 PM on 18 May 2010The significance of the CO2 lag
RSVP writes: "warming causes more CO2 and more CO2 causes warming" Taken to its logical conclusion, this statement implies a runaway effect... (assuming an unlimited supply of CO2). Nope, that's wrong. In addition to Chris's explanation, see this other thread here and the graphs here. A given forcing (of either CO2 or warming) will produce more CO2 and more warming, because of the positive feedbacks. But unless the forcing keeps increasing, both CO2 and temperature will converge on some new, higher value, with no runaway effect (unless you add enough heat or CO2 to cause a regime shift a la Venus). -
Daved Green at 19:32 PM on 18 May 2010The significance of the CO2 lag
does not anyone find this a bit scary ?? -
chris at 18:39 PM on 18 May 2010The significance of the CO2 lag
no it doesn't RSVP let's take the value of a [CO2] response to warming of 15 ppm (equilibium rise in [CO2]) per oC. let's say that during the early Holcene (no human contribution to changes in atmospheric [CO2]) the Earth temperature was suddenly to rise by 1 oC. Atmospheric [CO2] would slowly rise from 270 ppm to 270 +15 = 285 ppm. We can esily calculate the consequent temperature response. Let's assume a climate sensitivity of 3 oC (of Earth surface warming at equilibrium per doubling of [CO2]). The temperature rise is close to 0.23 oC. This will induce a recruitment of more [CO2] (the CO2 response to enhanced temperature). This is 15 ppm x 0.23 = 3.6 ppm. The temperature response from this enhanced [CO2] (285 + 3.6 ppm = 288.6 ppm) is around 0.05 oC. This will recruit an extra 15 ppm x 0.05 = 0.75 ppm of [CO2]... ...and so on. In other words the two feedacks: [CO2] feedback (15 + 3.6 + 0.75 + .....) ppm temperature feedback (0.23 + 0.05 + ...) oC converge to new equilibrium values. i.e. no "runway effect" -
RSVP at 18:03 PM on 18 May 2010The significance of the CO2 lag
"warming causes more CO2 and more CO2 causes warming" Taken to its logical conclusion, this statement implies a runaway effect... (assuming an unlimited supply of CO2). -
MarkR at 18:01 PM on 18 May 2010The significance of the CO2 lag
I don't have time to read the paper yet, but I do wonder: as I understand it, a lo of the feedback is mostly from the oceans. Henry's Law says that both temperature and partial pressure of CO2 control the rate of CO2 dissolving. We now have drastically increased partial pressure by a factor of larger than the temperature change: might this not stop the CO2 feedback? At most, we should just expect a declining percentage of dissolving CO2 and eventually an increasing airborne fraction. -
babelsguy at 17:50 PM on 18 May 2010Increasing CO2 has little to no effect
doug_bostrom, well, that is the interesting thing: He claims that his "study" would avoid all discussion of other issues but just show that CO2 (and the other GHGs) *cannot* be the culprit due to what he calls the energy balance question... -
Riccardo at 17:40 PM on 18 May 2010There's no empirical evidence
PaulK, the heat balance equation can be solved analytically for a forcing linear in time F=b*t (Schwartz 2007); neglecting feedbacks: DT(t) = b*((t-tau)+tau*exp(-t/tau))/l where tau is the response time (=C/l with C heat capacity) and l is the climate sensitivity. For small deviations from equilibrium, i.e. DT<< Te, the increasing thermal radiation E is proportional to DT, E=c1*DT. If the linear forcing is due to an increasing IR absorption (e.g. exponentially increasing CO2 concentration), the total OLR is: OLR(t) = E - F = c1*DT - b*t which, grouping all the constants together for simplicity, can be written as: OLR(t) = c*((t-tau)+tau*exp(-t/tau))-b*t The first term in the equation above is linear for t>>tau and one can write: OLR(t) ~ (c-b)*t - c*tau ; for t>>tau what governs the slope of the OLR is then the term (c-b) which can be positive or negative. For short times, instead, the slope of the OLR is always negative: d OLR/dt = c*(1-exp(-t/tau))-b*t ~ -b*t ; for small t In a few words, with a linear forcing DT will always increase linearly for time much longer than the characteristic response time of the system while OLR may increase or decrease depending on the strength of the forcing. What I (inappropiately) called runaway warming is when you have a continuosly decreasing OLR. -
quokka at 16:58 PM on 18 May 2010Species extinctions happening before our eyes
#52 nofreewind: In the abstract Eschenbach states "Very few continental birds or mammals are recorded as having gone extinct, and none have gone extinct from habitat reduction alone. No continental forest bird or mammal is recorded as having gone extinct from any cause." Having a look at the Australian government's list of extinct species, there are 27 mammals: http://www.environment.gov.au/cgi-bin/sprat/public/publicthreatenedlist.pl?wanted=fauna#mammals_extinct Among them is the Crescent Nail-tail Wallaby, which inhabited woodlands. Among the extinct birds are the Rufous Bristlebird (western), South-western Rufous Bristlebird which lived in forests. I didn't get past the abstract. There is only so much WUWT I can take in one sitting. -
PaulK at 16:04 PM on 18 May 2010There's no empirical evidence
As above but with some corrected subscript problems in this version. Riccardo #53 Thanks for the response. I don’t actually disagree with anything you have written, but I believe that you need to follow your conclusions to the next logical step. I wrote initially: “For an idealised system the OLR perturbation response to a year-on-year geometric growth in CO2 should be a monotonic decrease in OLR upto the equilibration time and a constant (negative perturbation) value thereafter.” I think that you are agreeing with this, but let me expand a little. Consider a single ANNUAL pulse of CO2 and an OLR response function in time, f(t), on (0,te), where te is the equilibration time. This function has the properties:- f(t) = 0 at t=0 f(t) <0 for all 0 is less than t is less than te, and f(t) = 0 for all t>=te. Let us define the integral of this function between 0 and t as F(t). The area subtended by the curve at t=te is the FINITE net energy received by the planet as a result of the single year pulse. Call this absolute value Ea. Or we can write F(te) = -Ea. Ea can be related to an increase in the temperature of the planet at equilibrium via the specific heat of the system. For a geometric growth model of CO2, the second year pulse yields an identical response to the first year with an energy commitment of Ea, and the third year is the same as the second and so on. In fact, each year we are adding the same energy commitment, for as long as the geometric growth continues. Now consider the multiyear solution obtained by stacking (superposing) the single year solutions. The stacked solution for OLR approximates to F(t) for t is less than te and becomes a constant negative Ea thereafter. (This is an algebraic identity. I won’t prove this here, but you can confirm it numerically for yourself on a spreadsheet in a matter of minutes.) This is not “runaway” warming. It corresponds to a linear increase in planetary temperature after time te - exactly what one would expect given a logarithmic relationship between CO2 and equilibrium temperature and a geometric growth in CO2. Note also that since f(t) all sits on one side of the zero line, the integral form F(t) is MONOTONIC decreasing (or increasing in a negative direction) irrespective of the choice of functional form for f(t). In the real world, we would not expect to see the monotonic OLR response implied by this solution, but we would expect to see a decreasing trend in OLR if CO2 were the PRIMARY driver of the temperature change - for the reasons I stated in my earlier post. During this period, if CO2 were the primary driver, we therefore should have seen simultaneously a decreasing trend in OLR, a decreasing trend in brightness temperature and an increasing trend in surface temperature. The reason for the opposite signs in brightness temperature and surface temperature come from the increase in downwelling radiation from the continuously added CO2. I do not believe that one can argue (as you seem to) that thermal emissions have overtaken the effects of CO2 on OLR and at the same time that CO2 is the PRIMARY driver of heating over this period. The two things cannot be readily reconciled and indeed this position probably threatens 2nd Law. -
Marcus at 14:52 PM on 18 May 2010Species extinctions happening before our eyes
Please do cite your sources Arkadiusz. I've spent a lot of time looking at close to a dozen paleo-climate reconstructions, & the range of warming over the Medieval Warm Period is usually the same-roughly +0.7 degrees (wrt 1961-1990 average) between 600 AD & 1200 AD (or delta T of +0.012 degrees/decade) & a cooling of 0.6 degrees between 1300 AD & 1600 AD, or -0.02 degrees per decade. Neither of these climate change events come even *close* to the warming of +0.12 degrees per decade that we've seen in the last 50 years, or the almost +0.16 degrees per decade we've seen in the last 30 years-especially when one considers the lack of forcings! -
quokka at 14:39 PM on 18 May 2010Skeptical Science housekeeping: navigation, comments and Thai translation
Wrt to a glossary, one of the easiest ways of getting started may be to contact other friendly sites that have one and ask permission to reproduce portions (or even the whole thing) with appropriate acknowledgements. Even organizations such as NOAA might be agreeable. I'd expect some conditions such as verbatim transcription, and a commitment to keep it up to date, which is fair enough. -
Tom Dayton at 14:22 PM on 18 May 2010CO2 measurements are suspect
johnd, you're now moving on to the topic of CO2 residence time, which has a considerable number of facts and links on a different thread: CO2 has a short residence time. We all can continue this conversation over there, if that's the topic onto which you are moving. -
johnd at 13:56 PM on 18 May 2010CO2 measurements are suspect
Tom Dayton at 12:26 PM, thanks for that article, it goes part of the way, the other part being how the variations in CO2 levels interacts with plants that are far closer to CO2 starvation levels than optimum. Do they take in more when the CO2 levels are higher, thus stripping the CO2 out at a higher rate? What the article indicates firstly is that understanding of the processes is still very limited, and that what occurs in the real world of complex and infinitely variable conditions is vastly different, not only from what is at times studied in laboratories under fixed and tightly controlled conditions, but also from some of the rather simplistic generalisations by which many of the AGW subjects are understood by many. This limited understanding of the processes as indicated in the article is perhaps reflected in the differences between some of the modelled and observed data. What is also clear from the article is that the transportation of CO2 at the near surface occurs as part of the weather system which is all about the redistribution of heat energy. What is does not address is the relationship between the belief that CO2 has a residence time of a century or more when the movement of CO2 near the surface satisfies the more immediate requirements of the plants, soil and oceans as both a source and a sink for carbon that requires an equivalent amount of the total atmosphere to be turned over every 3.5 years approximately. Is it that the CO2 high in the atmosphere plays no part in the surface exchanges and is merely the remainder left over? If so does the measurement of this non active participant include or allow for the more variable and highly mobile CO2 at the surface? One wonders whether a statistician studying the utilisation of a swimming pool only counts those passive sunbathers lying on the lawn soaking up the solar energy, using them as a convenient indicator, or does he also count those swimmers who are constantly climbing out of the pool onto the edge and shaking off moisture before diving in again. Getting an accurate count of one group would be easy, nigh impossible for the other in a crowded pool. -
Tom Dayton at 13:46 PM on 18 May 2010CO2 measurements are suspect
johnd, a less technical and much shorter explanation of CO2's thorough mixing in the atmosphere is given on page 8 of the EPA's Response to Public Comments, Volume 2, in the section "Response 2-8":"...turbulent mixing (e.g., through wind and convection) dominates the distribution of gases throughout the atmosphere (below 100 kilometers in altitude). The mixing of substances in a gas or fluid is only dependent on mass when the gas or fluid is perfectly still, or when the pressure of the gas is low enough that there is not much interaction between the molecules. Therefore, all long-lived gases become well-mixed at large distances from their sources or sinks over a period of one to two years...."
You should also read Response 2-3, regarding lifetime. And some of the nearby Responses. -
Ned at 12:51 PM on 18 May 2010On the reliability of the U.S. Surface Temperature Record
For a while Watts et al. were saying the problem was the decline in numbers of rural stations, or high-latitude stations. When it became clear that neither of these affects the temperature trend, I began noticing more and more contrarians saying that it's all because of airports. Now, Clear Climate Code has done a nice analysis showing no real difference in trend between airport and non-airport sites -- or, insofar as there is a difference, airport sites have had less warming than non-airports. So, once again, Watts etc have been quick to jump to conclusions with no evidence, and then were proved wrong when somebody actually bothered to sit down and do a quantitative analysis. It's, like, deja vu all over again! -
Tom Dayton at 12:26 PM on 18 May 2010CO2 measurements are suspect
johnd, maybe this article by Parazoo et al. has the kind of info you're looking for. -
nofreewind at 11:25 AM on 18 May 2010Species extinctions happening before our eyes
Can anyone comment on why this article,Where Are The Corpses?, is not valid. It does not discuss reptiles and amphibians, but looks at birds and mammals. -
Ned at 11:21 AM on 18 May 2010CO2 measurements are suspect
I agree with Doug that johnd needs to be more clear about what specifically he's claiming. Looking back up-thread to johnd's comment here, I see the question "What would be the means that allows CO2 to be well mixed in the atmosphere whereas heat is not." The main answer to that is "residence time." The residence time of CO2 in the atmosphere is very long (on the order of a century or so). The residence time of heat in the atmosphere is very short. (Water vapor, one of the vehicles for heat in the atmosphere, has a residence time of about nine or ten days). Thus, CO2 sticks around long enough to become well-mixed, while heat does not. -
Doug Bostrom at 09:49 AM on 18 May 2010CO2 measurements are suspect
Sorry johnd, you've lost me, I don't understand what you're driving at. I think you're saying that heat has something to do with the carbon cycle, and that unless CO2 is "stirred" up somehow and driven into contact with the surface the carbon cycle can't work? That's what I take from your post here, anyway. I don't know why you're asking me whether I think there's a carbon cycle in operation. Something to do with my question about mixing of other gases, I suppose. -
johnd at 09:41 AM on 18 May 2010CO2 measurements are suspect
doug_bostrom at 09:04 AM, please correct me if I am wrong, but the carbon cycle and the sequestration and liberation of CO2 at the earths surface by plants, soil and oceans has been established as a fact, and gone beyond being a hypothesis. Yes or no? With regards to heat, perhaps if you provided some data regarding the processes that you feel surely would apply to the mixing of O2 as they do to CO2, then we will have some basis to examine as to whether they do or not. Given oxygen makes up over 20% of the atmosphere whereas CO2 is a minor trace gas, the means that would have to be applied so that such a minor trace gas will become evenly distributed could be expected to apply to all other elements present in the atmosphere, including heat which always seeks to find equilibrium. -
Doug Bostrom at 09:04 AM on 18 May 2010CO2 measurements are suspect
Johnd, just so we're clear, I understand you to hypothesize that some concentration of C02 is required at the surface in order for the carbon cycle to work? Or are you saying that we -ought- to see a concentration of C02 at the surface -if- there is a carbon cycle? Your original explanation is leaving me scratching my head. What does heat have to do with it? -
johnd at 07:27 AM on 18 May 2010CO2 measurements are suspect
doug_bostrom at 05:01 AM, since when has the sequestration and liberation of carbon between the atmosphere and the plants, soil and ocean been returned to being a mere hypothesis. Perhaps the data on what proportion of atmospheric oxygen is involved in similar exchange processes at the surface as CO2 would provide a clue. What does that tell you? The carbon cycle requires CO2 to be sequestered at the very surface of the planet from where it is also liberated. On an annual basis about 200Gt of C is sequestered and 200Gt liberated by processes that occur at the surface. This is out of a total of 750Gt of C present in the air giving an equivalent total turnover time of 3.5 years. If a similarly high proportion of oxygen does turnover within a similar time frame than surely you would agree that heat distribution throughout the atmosphere would also be well mixed, oxygen being such a high proportion of the atmosphere rather than a trace gas?
Prev 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 Next
