Arguments
Recent Comments
Prev 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 Next
Comments 106051 to 106100:
-
mistermack at 08:12 AM on 23 October 2010CO2 lags temperature
Tom, to call it physics is stretching it. It's the brand-new science of climate prediction, that has no previous experience to draw on, and a track record of no successful predictions thus far. You are waaaay overstating the solidness of the science. If it was as straight-forward as physics, they could tell us the climate for next year.Moderator Response: Regarding success of models, you really need to comment on (after reading) the thread "Models are Unreliable." Type that into the Search field at the top left of this page. -
archiesteel at 08:12 AM on 23 October 2010Newcomers, Start Here
@David: welcome to this site, you'll find a treasure trove of scientific material here. As for yuor question, there's several things to note: A 10-year old trend for HADCRUT3 NH data doesn't show a decrease, but a small increase:The second is that 10 years is much too short to derive a statistically significant trend. Otherwise, you'd be able to say temperatures have risen by 2C/decade in the Norther hemisphere since 2008... (the short blue line above). That doesn't mean much. In climate science, the longer the data set, the more accurate the trends. Finally, why only consider the NH hemisphere? The two hemispheres are part of the same system.
-
mistermack at 08:03 AM on 23 October 2010CO2 lags temperature
Hi e, thanks for the link. But I immediatly noticed that the graduations are in 100,000 year sections, which makes it look spikey. Also, this is not "whole planet, whole year" insolation, it's one single day, at one single line of latitude. -
CO2 lags temperature
mistermack, it's not valid to assume how big, or significant that would be, or that it can go past certain limits. Nobody is assuming. Predictions are made by the physical theory and tested via experiment and evidence. Inventing "limits" where the physics predicts none is certainly not valid. You seem to have a profound misconception of how climate science makes its predictions. It is not a guessing game based on historical reconstructions. It is a direct physical prediction given specific explanations of the mechanisms at play in our climate. Historical data only serves as evidence to support these physical theories. -
Tom Dayton at 07:54 AM on 23 October 2010CO2 lags temperature
No, mistermack, it is not "guesswork." It's basic physics plus advanced physics plus sophisticated but perfectly sensible and comprehensible models of how all that works together, validated against observations. Really, you should start reading more, because you are claiming total absence of evidence when there is a lot of evidence. -
David Wrathall at 07:50 AM on 23 October 2010Newcomers, Start Here
I'm a science teacher and coordinator for sustainable development at a secondary school in England. I've been following a debate on climate change between Alastair McIntosh, author of "Hell and High Water" and Peter Taylor, author of "CHILL". ECOS Climate Change Debate It's definately worth a look; particularly the most recent post from Peter. Dr. Wilson Flood from the Royal Society of Chemistry has joined the debate and contributed a link to interpretation of data from Meteosat that shows cooling in the Northern Hemisphere since 2001. Meteosat data interpreted by Dutch meteorological analysts What do you make of this? What could have caused this phenomenon? -
CO2 lags temperature
mistermack> I have read plenty on the Milankovitch cycles, and I can assure you that there is nothing in the calculated insolation rates that could possibly cause such sudden changes. The changes in the insolation curve are plenty sudden in relation to the temperature cycles. Also, here is an example of a model that accurately recreates these temperature trends using insolation as the primary driver. -
Doug Bostrom at 07:39 AM on 23 October 2010The 2nd law of thermodynamics and the greenhouse effect
Here's a nice little analogy, rigorously tested and free of convection and other distractions: The equipment compartments are insulated by multi-layered blankets of aluminized plastic. Temperature-responsive louvers at the bottom of the equipment compartment, opened by bi-metallic springs, allow controlled escape of excess heat. Other equipment has individual thermal insulation and is warmed by electric heaters and 12 one-watt radioisotope heaters, fueled with plutonium-238. The Pioneer Jupiter Spacecraft That's a technique often used for thermal control of spacecraft: The thermal control of the spacecraft was intended to be as passive or automatic as possible. The greatest part of the heat load came from the Sun and a lesser amount from the onboard electronics equipment, the latter also being among the most heat-sensitive components. For passive control, materials with different absorption and emission properties were used to radiatively balance the heat within the spacecraft. In addition, one of the six [25] boxes around the hexagonal structure was fitted with louvers activated by a temperature-sensitive bimetallic element. If temperatures within the box rose too high, the louvers opened to radiate the heat to black space; when temperatures were too low, the louvers closed to keep in the heat generated by electronic components. SP-480 Far Travelers: The Exploring Machines: Creating an Exploring Machine Were these louvers cooler than the spacecraft? Were they heating the spacecraft? CO2, water vapor. Louvers. -
mistermack at 07:38 AM on 23 October 2010CO2 lags temperature
It's valid to assume a greenhouse effect for CO2, it's not valid to assume how big, or significant that would be, or that it can go past certain limits. Take the example of heating a nail in a flame. It's dead easy to take the chill from the nail. It's harder to get it very hot, and harder still to make it glow red-hot. This is because hot surfaces radiate heat faster. The earth may well have a mechanism that stops it getting hotter, once it reaches the tipping point of the spikes on that graph. You can point to hotter times millions of years ago, but we are now in an ice-age. It's different now. There's no evidence for or against warming with co2 levels as high as they are now, with global temperatures as they are now. You are assuming current levels of co2 can push it higher. There is no previous circumstance to base that model on. Fair enough you can "claim" that the extra co2 we have now will have the power to push it past previous limits. But that's all it is, someone's guesswork. -
Waste heat vs greenhouse warming
Small amusement (if the moderators let this by) - here's a nuclear powered car. No CO2 contribution at all, although I'm not fond of the idea of riding in front of a hot neutron source...
Moderator Response: That would be a perfect fit in the "Are we too stupid" topic. :-) -
archiesteel at 07:33 AM on 23 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Also, you have been asked repeatedly: could you provide the data you used to generate your graphs? Thanks. -
archiesteel at 07:32 AM on 23 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
@FLansner: "As I see it DMI data, mostly ERA-40 data shows that GISS data over the Arctic are not accurate." ...and yet both GISS and DMI show the same warming trend, as demonstrated above. How do you respond to this? Your site is under attack because the science presented on it is of shoddy quality. You were right before caving in to peer pressure from your friends, who were wrong on the science. Here, however, is a lot of scientific literature about the subject. I suggest you stop posting and start reading instead. -
Waste heat vs greenhouse warming
RSVP - As a thought experiment, consider a world where all of our power came from non-CO2 sources (Nuclear, perhaps?). Change in regards to radiative forcings (energy input) is formulated as: dT = λ*dF Where dT is the temperature change, λ the sensitivity, and dF the radiative forcing change. Given an anthropogenic heat flux of 0.028 W/m^2, and a climate sensitivity of 0.54 to 1.2°C/(W-m-2) for λ, you can calculate that: The expected equilibrium global warming contribution from AHF would be 0.01512°C to 0.0336°C. That amount is totally lost in climate noise. We've seen a change of 0.8°C in just the last 40 years, and we're far from equilibrium. AHF contributes, but it's only a tiny contribution. It's not the dominant cause by two orders of magnitude. -
archiesteel at 07:26 AM on 23 October 2010Waste heat vs greenhouse warming
@RSVP: "When this post got started, the reason AWH was being ignored was due to numbers, now it appears to be impossible according to what you are saying in 277." Actually, that's not what he said at all. He specified it does have an effect, but such a small one it would get drowned in the noise. -
FLansner at 07:24 AM on 23 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Ok, Bikliovermis, it was just not my intension to do name calling. Skeptics are called skeptics, but what can we call the other fraction? I have seen "Alarmists" , "warmies" etc etc, but whats is the correct term?? "Conspiracy": I think that some people in good intension has exaggerated. But im not allowed to say more here. Antarctic: I was asked about how/why i turned skeptic, and Antarctic was a key explanation here. And im just not used to blogs so strict on the topic. And then is would like to defend my site hidethedecline that is under attack in coments, but its outside this blog. So back to the subject: As I see it DMI data, mostly ERA-40 data shows that GISS data over the Arctic are not accurate. My original article also showed that GISS temperatures projected over ocean matches Hadley SST poorly. Any objections when all comes to all? K.R. Frank -
archiesteel at 07:17 AM on 23 October 2010CO2 lags temperature
@mistermack: "According to the models, 800 years of steeply rising co2 should cause at least 750 years of more temperature rises, not a steep plunge." Check out CO2 is not the only driver of climate change for more details on how temperatures could have started to decrease even though CO2 concentrations were still near the high "normal" range (again, much lower than current CO2 concentrations). -
archiesteel at 07:12 AM on 23 October 2010CO2 lags temperature
@mistermack: "Thanks archiesteel, but you're using your conclusion in your argument there." No, I'm not. I'm basing my argument on established science, i.e. the greenhouse effect. Are you going to argue the greenhouse effect isn't real? I remember another skeptic in another thread who recently said "no one disputes the greenhouse effect..." "Why did an obvious violent feedback mechanism suddenly stop, and go into equally violent reverse?" If you're speaking about Young Dryas specifically, it seems the lingering Laurentide ice sheet played a major impact in it. As far as the glacial/interglacial cycle goes, Milankovitch cycles are primarily responsible for that. BTW, CO2 is not a feedback, it's a forcing (though heating does release some CO2 from the oceans, so I guess it's both, ultimately). "Until you can answer that, it's surely unjustified to claim that the warming that's happening today won't meet the same "barrier" that warming did in the past." It won't meet the same barrier because CO2 concentrations are much higher today than they've been throughout the current Ice Age. -
Adam C at 07:05 AM on 23 October 2010The 2nd law of thermodynamics and the greenhouse effect
I like the description of the blanket analogy in #3 better than in the post. It seems to me important to point out that the blanket makes you warmer despite the fact that the blanket is colder than you are. By denialist logic blankets also violate the 2nd Law. -
RSVP at 07:03 AM on 23 October 2010Waste heat vs greenhouse warming
KR #277 "You've long since left the realm of scientific discussion." Since you seem to know so much, I would ask if you think it even be possible for anthropogenic waste heat to cause global warming? Not the amount that we are currently putting out, but some other larger amount. When this post got started, the reason AWH was being ignored was due to numbers, now it appears to be impossible according to what you are saying in 277. Which does it happen to be, or does the reason change with the zodiac? -
Doug Bostrom at 06:43 AM on 23 October 2010CO2 lags temperature
BTW Mistermack, it would be helpful if you could confirm you have noticed the difference in CO2 concentration between the graph above and today. -
Tom Dayton at 06:38 AM on 23 October 2010The science isn't settled
mistermack, there is a condensed list of claims with their certainties on this EPA page "State of Knowledge". If you are unhappy with the lack of detail there, then look in the IPCC Working Group I Summary for Policymakers. If you are unhappy the lack of detail there, then dig into the body of that IPCC report. You might also want to ask for a copy of the content of a poster presented at the AGU conference in 2009, by Martin Vezer, titled A Defence of the AR4's Bayesian Approach to Quantifying Uncertainty. -
Doug Bostrom at 06:25 AM on 23 October 2010CO2 lags temperature
Mistermack, when you speak of models being wrong, do you mean somebody has attempted to model past glacial episodes and has failed? As to sensitivity being "guesswork," the largest ball of uncertainty remaining in the air and the one most people studying climate agree is most likely to surprise is the role of clouds. Characterizing sensitivity as guesswork is a departure into hyperbole. Specific discussion of uncertainty might better be conducted on the What is our planet's climate sensitivity?" thread. -
Bibliovermis at 06:25 AM on 23 October 2010The science isn't settled
If there was a 90% certainty, based on scientific analysis, that a given model of plane would fall out of the sky, would you board that plane? Or would you dismiss those claims because there is still quite a lot we are missing in the study of aerodynamics? -
Tom Dayton at 06:19 AM on 23 October 2010The science isn't settled
mistermack, that "90% certainty" is for a very particular claim. It's not just for the non-technical masses. Other claims have less or more certainty. I suggest you read a January 2010 article by Trenberth, "More Knowledge, Less Certainty", about the lower certainties that will come along with the IPCC's next report's projections. -
Tarcisio José D at 06:16 AM on 23 October 2010The 2nd law of thermodynamics and the greenhouse effect
Argumentação muito fraca frente a um processo extremamente complexo como o aquecimento da atmosfera. Vejamos. O sol envia para a terra 1368 W/m2 de energia radiante. Ao penetrar na atmosfera (troposfera) esta energia encontra nuvens e as converte em vapor de agua e reflete algo de volta ao espaço. Chegam ao solo algo em torno de 965,6 W/m2. No solo aquecido encontramos; 1- Calor irradiado (IR) 595,3 W/m2 2- Calor transferido ao ar por contato 616,3 W/m2. (convecção) 3- Calor absorvido pelo solo 246,3 W/m2 Somatorio da energia no solo 1457,9 W/m2 assim distribuidos 492,3 W/m2 irradiados pela atmosfera e 965,6 W/m2 provenientes do sol. Este 492,3 W/m2 é que representa o efeito estufa aqui em Manaus. Dum total de 1457,9 W/m2 apenas 616,3 (item 2) estão sujeitos à segunda lei da termodinamica que é respeitada em sua integra. A segunda lei da termodinamoca refere-se a transferecia de calor entre os corpos pelo processo de condução e neste caso só é aplicavel à convecção (item 2) pois o restante segue a lei da irradiação. Este exemplo é de condições local entre as 14 e 15 horas, pois a transferencia por convecção requer que o solo esteja mais quente que o ar ambiente. O que não ocorre à noite. Efeito estufa em Manaus... Very weak argument against an extremely complex process like the heating of the atmosphere. Let's see. The sun sends to earth 1368 W/m2 of radiant energy. By penetrating the atmosphere (troposphere) this energy convert the clouds into water vapor and reflects something back to space. Reach the ground somewhere around 965.6 W/m2. In the soil heated encounter; 1 - Heat irradiated (IR) 595.3 W/m2 2 - Heat transferred to the air by contact 616.3 W/m2. (Convection) 3 - Heat absorbed by the soil 246.3 W/m2 Sum of the energy in the soil 1457.9 W/m2 distributed, 492,3 W/m2 irradiated by the atmosphere and 965.6 W/m2 from the sun. This 492.3 W/m2 represents the greenhouse effect here in Manaus. Of a total of 1457.9 W/m2 only 616.3 W/m2(item 2) are subject to the second law of thermodynamics and is respected in its entirety. The second law of thermodynamics concerns of transfer of heat between the bodies and the process of conducting this case is only applicable to convection (item 2) because the remainder follows the law of irradiation. This example is from local conditions between 14 and 15 hours, for transfer by convection requires that the soil is warmer than the ambient air. What does not occur at night. -
mistermack at 05:57 AM on 23 October 2010The science isn't settled
This 90% certainty that the IPCC claim is hugely simplified, for the non-techincal masses. I would say it's near 100% for some effect, but as to how much warming corresponds to how much CO2, that 90% figure for most of it is just a shot in the dark by the IPCC. It assumes our understanding of climate-forcing factors is nearly complete. I think there is still quite a lot we are missing. -
mistermack at 05:39 AM on 23 October 2010CO2 lags temperature
Tom, thanks for that link about the "burp from the deep". It's interesting, but tantalisingly low on detail. And I can't make out if they are talking about CO or CO2. They write CO, but talk about CO2. I'll try to find more on it. It doesn't apply to the peaks I was talking about, but could be involved in the troughs, the ending of the ice age. I would have thought though, that such an event would show clearly in the Vostok ice-cores. -
Are we too stupid?
There's a nice feasibility study of converting the US (and the world) to completely renewable energy sources, Jacobson et al 2009, also Jacobson 2009. Total world power needs est. for 2030: 17 TW. Solar power in likely-to-develop locations (high insolation): 340 TW for photovoltaic, ~240 for concentrating thermal solar. Wind power in likely-to-develop locations: 70-170 TW. Likely to develop locations for wind (high wind density) include the Great Plains of the U.S. and Canada, Northern Europe, the Gobi and Sahara Deserts, much of the Australian desert areas, and parts of South Africa and Southern South America. For the US alone the Great Plains and off the East Coast would be sufficient. Slide 18 of Jacobson 2009 is particularly interesting - demonstrating the relative area required to produce sufficient electricity for all US vehicles. Both wind turbine area and area with turbine spacings (which can be dual use) are shown. This looks quite feasible. -
Bibliovermis at 05:06 AM on 23 October 2010DMI and GISS Arctic Temperatures: Hide the Increase?
Frank, The very name of your site is a conspiracy notion. You started the name calling with terms such as "warmies", alarmist & believers. Indignation does not trump moderation. This page is on the topic of DMI data, not on the notion of widespread malfeasance in the scientific community. -
mistermack at 04:59 AM on 23 October 2010CO2 lags temperature
Doug and Tom, thanks for your comments. I of course don't dispute co2 acting as a greenhouse gas. But the amount of warming, for a specific increase, is only guesswork at the moment. (otherwise, why is the IPCC only claiming 90% certainty? That leave 10% chance that the current levels are not to blame, does it not?) The problem I'm pointing out with the graphs above, is that at the peak of previous warming, you get an 800 year period, when co2 levels are high, and rising steeply, and yet temperatures are plummeting. This is in stark contrast to todays models. And our point in the cycle now is at or near that historic maximum. I don't see any explanation why the models are so wrong, for so long, for these events. The Milankovitch cycles just don't cut it. The insolation curves are extremely gentle.Moderator Response: Regarding uncertainty, please read (and comment there) the Argument "The science isn’t settled". Be sure to check out both the Basic and Advanced tabbed pages there. -
Tom Dayton at 04:53 AM on 23 October 2010CO2 lags temperature
mistermack, Multiple, interrelated, not entirely synchronous factors were responsible for both the onset and offset of ice ages. They are not understood completely, to say the least. But just one example of how those factors can have sudden onsets and offsets is the recently discovered CO2 "burp" from the deep ocean. -
CO2 lags temperature
mistermack, Yes, which is why feedbacks are required to account for the degree of temperature swings. The models accurately recreate these temperature swings, so your claim that the models are inconsistent with the models is wrong and nonsensical. -
Doug Bostrom at 04:45 AM on 23 October 2010Do critics of the hockey stick realise what they're arguing for?
The title of Lamb's paper is wholly ironic considering how it was deployed here. So, a laugh at least. :-) -
Tom Dayton at 04:40 AM on 23 October 2010CO2 lags temperature
mistermack, Amplifying e's comment about your point 2: The main evidence for CO2's warming effect is not passive observation of its historic relationship to temperature. Rather, it is fundamental physics. CO2's warming effect was postulated in the early 1800s, long before there was evidence of its historic relationship to global temperatures. The exact mechanism by which CO2 does that was discovered in the early 1900s, again before there was much historic evidence. Later the historic relationships were discovered and found to match those predictions. For a good summary of the physics see Ramanathan's paper. For a good history see Weart's The Discovery of Global Warming. -
Doug Bostrom at 04:39 AM on 23 October 2010CO2 lags temperature
Mistermack, you related yesterday's behavior to today's behavior, yourself suggesting that yesterday's behavior is cause to doubt what will happen today. As has been pointed out to you, today is different. Again, look at the CO2 concentration in times you refer to, compared to today. On a side note, it's not an "assumption" that increasing concentrations of CO2 cause the atmosphere to be a more efficient insulator. If you want to argue about that, however, use the search function to find a suitable venue for chasing that topic. -
mistermack at 04:37 AM on 23 October 2010CO2 lags temperature
Hi e, I have read plenty on the Milankovitch cycles, and I can assure you that there is nothing in the calculated insolation rates that could possibly cause such sudden changes. And nothing in any Milankovitch cycle that could suddenly negate 800 years of steeply rising co2 levels, if the models are correct. -
Stephen Baines at 04:36 AM on 23 October 2010Climate cherry pickers: Falling humidity
Obviously, when I wrote "So the effect of temperature is indirect..." I meant "the effect of solar radiation." Basically the discussion boils down to this, so to speak. You should get more water vapor as earth's temperature warms. If that didn't happen, it would be really really interesting scientifically - a potential Nature or Science paper and fame for anyone who could prove it. However, the strength of the physics behind the expectation, the fact that most data collected to date clearly shows a response of water vapor to atmospheric temperatures, and the difficulty in accomodating for past climate change in the absence of such a relationship suggests we should look at countervailing evidence with a very critical eye, especially when we know how easy it is to misinterpretation radiosonde data. -
CBDunkerson at 04:31 AM on 23 October 2010Are we too stupid?
BP #129: "All the other alternative energy sources one by one or all together do not even come close to replace carbon based fuels, just do the math." Ok. Current world energy consumption: ~16 TW Estimated exploitable world renewable resources with current technology; Hydro: 2 TW (out of 7 total) Geothermal: 1 TW (out of 30 total) Wind: 70 TW (out of 850 total) Solar: Estimates vary widely, but 600 TW is the lowest I could find. (out of 120,000 total). Somehow I'm not seeing the problem in getting up to 16 TW. Must be 'new math'. "With solar you need storage" No, with solar you need storage, a backup power source to smooth out fluctuations, a large/efficient enough grid to always have power available somewhere from the network, OR some combination of the above. Viable options exist for all three solutions with current technology. "Present consumption could be covered using just about half a million km2 (0.3% of land surface). However, we can't go much above this level before this kind of energy supply starts to compete with plants for sunlight." What? If there are no plants where you put the solar collectors then they aren't competing with plants for sunlight. Deserts, rooftops, blacktop... each of these can provide a 'plant free' area of more than 0.3% of the planet's land surface. BTW, plant photosynthesis uses less than 0.1% of the solar energy which strikes the planet's surface each year. -
CO2 lags temperature
mistermack, On point 1) You were told to read up on Milankovitch cycles. Milankovitch cycles are periodic shifts in the earths orbit. When the orbit moves closer to the sun we get the warming trend, when the orbit moves further from the sun the warming trend is reversed and we get a cooling trend. The orbital cycles drive the direction of temperature change while CO2 only acts as a feedback or amplifier of said changes. Get it? On point 2) You asked how current theory explains the temperature trends. You can't very well expect someone to explain current theory without using the theory itself. Also, Milankovitch cycles on their own have nothing to with CO2, CO2 just acts as a feedback. If your question is what evidence do we have that CO2 levels are causing GW, then that is a separate topic and is covered here. -
mistermack at 04:19 AM on 23 October 2010CO2 lags temperature
Ah, sorry about the caps. I wasn't intending it as a yell, just as emphasis, like underlining. -
mistermack at 04:04 AM on 23 October 2010CO2 lags temperature
I'm sorry, Tom, Doug and Biblio, but 1) that was no answer to why warming stopped before, and 2) You're using an assumption that GW is caused by CO2 levels, to argue for it. I think about the four peaks in temp. in the graph above. Just before that peak, temp was rising at an enormous rate, and so was CO2. Something stopped it suddenly, and sent it the other way, EVEN THOUGH CO2 WOULD CONTINUE RISING STEEPLY FOR ANOTHER 800 YEARS !! According to the models, 800 years of steeply rising co2 should cause at least 750 years of more temperature rises, not a steep plunge.Moderator Response: Please don't use all caps. It's considered yelling. See the Comments Policy. -
Tom Dayton at 04:02 AM on 23 October 2010CO2 lags temperature
mistermack, another difference between then and now is the time scale. The "sudden," "steep" rises and drops you see in those graphs of olden times are not so sudden or steep when plotted on the timescale of the recent, human-caused temperature rise of the past 150 years. -
JMurphy at 03:46 AM on 23 October 2010Do critics of the hockey stick realise what they're arguing for?
I agree, doug_bostrom. There is more about this (and its appearance in Wegman's dodgy report, and The Great Global Warming Swindle(sic) - which is probably where so-called skeptics get it from) at Stoat, where you will also learn that the graph is for Central England only - not global. As it says at Stoat : So: just in case it isn't clear from the above: fig 7.1.c isn't useful anymore. It was vaguely useful then because there was nothing better available. It was a hurridly drawn sourceless schematic that no-one uses nowadays; and if anyone *did* use it they would be roundly criticised. You can also read about it here at Skeptical Science. Try again, please, craig. -
rab at 03:34 AM on 23 October 2010The 2nd law of thermodynamics and the greenhouse effect
"If you put the blanket on a tailors dummy, which does not generate heat, it will have no effect. The dummy will not spontaneously get warmer. That's obvious too!" Don't be so sure about it being obvious. I once went hiking with a fairly intelligent but non-scientist friend, and having no good "thermos" (vacuum-insulated) bottle for our cold drinking water, took a plastic bottle, filled with ice water, and wrapped it in a sweater. She asked "What are you doing?". She assumed that the insulation would warm it up, not keep it cold. I think this is fairly typical thinking among non-scientists. -
Doug Bostrom at 03:28 AM on 23 October 2010Do critics of the hockey stick realise what they're arguing for?
"Recent" according to Craig: H. H. LAMB, 1965, THE EARLY MEDIEVAL WARM EPOCH AND ITS SEQUEL Palaeogeography, Palaeoclimatology, Palaeoecology -
Bibliovermis at 03:23 AM on 23 October 2010CO2 lags temperature
Mistermack, The information you are looking for is available on this site. I can't post direct links, since this is being tapped out from my phone. Read up on the Milankovitch cycles and climate sensitivity in regards to CO2 as a feedback agent. Currently, CO2 is the forcing agent rather than a feedback. This is why archiesteel's comment was spot on. -
Doug Bostrom at 03:20 AM on 23 October 2010CO2 lags temperature
Further to Tom's remarks, look at the ppm levels in the graph in John's post. We're at ~386ppm today, off that chart, in a new mode. "...it's surely unjustified to claim that the warming that's happening today won't meet the same "barrier" that warming did in the past. " The present warming's not going to meet the same barrier, that barrier's efficacy won't be the same today because we've created a novel situation. "Past is prologue" arguments always face the fundamental problem that we're not living in the past, we're living in the present, us and our effluent. -
Lou Grinzo at 03:13 AM on 23 October 2010The 2nd law of thermodynamics and the greenhouse effect
I would suggest that those who haven't seen the discussion on Spencer's site about this take the time (and you'll need a lot of it) to look it up and wade through it. Spencer and a very small number of commenters (as I recall) do a heroic job of convincing the hard core deniers how reality works. It's about as perfect an example as I can imagine of how difficult communication can be. -
Are we too stupid?
There are certainly multiple renewable and non-renewable options. Nuclear options would require fast breeder reactors and/or thorium reactors; both are technically possible, although politically 'hot' due to the radionuclide and fissionable materials availability. They do require cooling water, which is a different resource issue. Solar is entirely possible with current technology (doesn't require nano-machining); it's currently still a bit too pricey to be economic, but that's dropping fairly fast. The big requirements there are (a) reliable wide-area transmission lines, (b) scattered siting to minimize regional cloud issues, and (c) the needs some solar tech have for rare elements. Covering a portion of the Saudi peninsula with panels would power the planet if we could distribute it, without competing for any food. There's some excellent work going on in terms of energy storage, including molten salt, and simple approaches such as pressurized underground reservoirs - pump air into a mine shaft, run turbines off it when needed. Wind power is plentiful, although not as large a supply as solar - it would be a good adjunct to solar systems, sharing some of the same storage/distribution framework needed. Both do require considerable excess capacity to handle low wind/light conditions. Further down the line are orbital solar (gets around clouds and some distribution problems), some interesting approaches such as fusion (not tokamaks, I suspect those will never work), like the Polywell reactor or some of the other geometries. However - all of these require infrastructure development, time to be built, investment to drop the prices to economically feasible levels, and the political will to choose low CO2 technologies over "business as usual". -
Stephen Baines at 03:10 AM on 23 October 2010Climate cherry pickers: Falling humidity
JohnD, the effect of solar radiation on evaporation is not "direct." Evaporation (and water vapor content) increases when the surface waters and wet soils warm, when the air warms and when wind allows the air near air/water interfaces to be replaced quickly before it saturates with water vapor. So the effect of temperature is indirect, through it's effect on surface and air temperatures. Since climate models are built on the fact that solar radiation is the primary source of heat energy into the system, variations in solar energy are built into predictions of atmospheric water vapor. They can't be causing the apparent increase in water vapor because there has been no recent increasing trend in solar inputs. In any case the existence of the water vapor feedback is not related to whether sun or GHGs are driving the temperature change. If the sun were causing the current warming, there should still be a water vapor feedback for that warming, just like there is for warming induced by icreases in GHGs. If there were no water vapor feedback, the climate system much more insensitive as a whole than it apparently is. It would be very hard to explain past climate variations, including those that have been caused by changes in solar radiation. As for the ocean discussion, we can quibble about how deep the skin is (I think of it as much thinner than a millimeter) and what consitutes a fraction that is large (13% still seems low to me). But there are several points your graphs bring up. First, whereas on land all the visible light waverlengths would be absorbed/reflected near the surface, visible light penetrates pretty deeply into the water column. That's the point I was trying to make about the difference between the ocean and land. Second, most of the solar radiation absorbed near the ocean surface is in the infrared range. If you were to extend that x-axis out, you'd find that the contribution of downwelling thermal IR to the near surface radiation budget is actually larger than that of downwelling solar IR. That downwelling thermal IR is of course a function of air temperature not solar radiation. Finally, the point of where the radiation is absorbed is moot in the ocean because that heat gets dispersed through the water column pretty quickly, as evidenced by the fact that you don't see strong persistent gradients in temperature near the surface. Sometimes this forum makes me feel like I'm reliving my prelims all over again!
Prev 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 Next
