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Captain Pithart at 21:51 PM on 1 July 2010A Scientific Guide to the 'Skeptics Handbook'
are you planning on doing translations? nova has her book translated into the following languages: Spanish ("El Manual del Escéptico") Japanese ("スケプティックハンドブック") Danish ("Håndbog for skeptikere") Balkans Translation (Bosnia, Croatia, Serbia) Portuguese ("O Manual dos Céticos")[5]: Fake Climate Turkish ("Şüphecilerin El Kitabı") Finnish ("Ilmastoskeptikon käsikirja") Ilmastofoorumi (kasikirja@ilmastifoorumi.fi) Norwegian ("Skeptikerens håndbok") Swedish ("Handbok För Klimattänkare") French ("Manuel du Sceptique") German ("Das Skeptiker-Handbuch") i'm not sure that makes sense; as her book has a very low level of entry, and i guess that most copies are hawked online, i don't think that many non-english speakers will stumble about your fine book. however, if you think translations would make sense, i could do the German one.Response: Just like the translations of the skeptic arguments (see flags at top of page), translations are very welcome. Anyone interested in translating the scientific guide, please contact me. Captain Pithart, I'll email you directly to organize details. -
SNRatio at 21:45 PM on 1 July 2010What causes the tropospheric hot spot?
" Is it conceivable that the lower troposphere is warming at about the same rate?" Should of course be: Is it conceivable that the lower troposphere and the surface is warming at about the same rate? -
SNRatio at 21:40 PM on 1 July 2010What causes the tropospheric hot spot?
Baa Humbug, I think the discussion of models and model predictions can be very misleading, as there is a very strong tendency on one side to stick to the modeling assumptions and think that the measurements are wrong. The IPCC is open to the possibility that their modeling is wrong, but they don't really believe it can be. On the other side, there are lots of flawed conclusions as to what really implies what. The basic phenomena here are: - Is the stratospere cooling or, at best, at constant temperature? Yes, it is. And this cooling is to be considered separately from anything that could occur elsewhere. Stratospheric cooling is cooling regardless of what might happen in the troposphere. - Is the troposphere, as a whole, warming? Yes, it is. This, too, is to be seen independently from what might happen further up or down. - Could this divergence be explained by the sun? No, not by any plausible model anyone has been able to produce. So far then, we have an observation of a GHG signature. Yes or no? - Is it conceivable that the lower troposphere is warming at about the same rate? Yes, it is. And in fact, that is what we seem to observe, with both the RSS and UAH temperature series. In fact, it is only during El Ninos we have, regularly, seen something else, with more warming of the troposphere. - Does this parallel warming contradict any laws of physics? Not necessarily, as there are several transport and conversion phenomena that could interact to produce the results we can observe. Whenever we have transport phenomena coupled with combinations of positive and negative feedbacks, as we have here, the results can become rather unpredictable, maybe even seemingly "non-determinstic". -
David Grocott at 21:37 PM on 1 July 2010What causes the tropospheric hot spot?
Hi Baa Humbug, No worries, I don't doubt your integrity. I wouldn't disagree with the thrust of your second and third *s, but with regards to the first one, all the charts presented do show warming across all latitudes as a result of GHG forcing. A 0°C change would be shown as white on my charts and cream on yours. As you can see this is not the case. The charts do model more warming at 30N to 30S at 8-10km aloft, but that doesn't mean they don't also anticipate the troposphere as a whole to be warming. -
VoxRat at 20:57 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
The link to the Climate Crock of the Week video doesn't work (for me, anyway). I'm guessing this might be what was intended: http://go2.wordpress.com/?id=725X1342&site=greenfyre.wordpress.com&url=http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DvFGU6qvkmTI&sref=http%3A%2F%2Fgreenfyre.wordpress.com%2Fdenier-vs-skeptic%2Fdenier-myths-debunked%2Fclimate-denial-crock-of-the-week%2F%23dont ... but perhaps there's a shorter way to link to it. -
chris at 20:51 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
A relevant paper published in today's Nature [*]. This reiterates that any [CO2] effect requires enhanced N (nitrogen) nutrient as is well known, but the combined effects of [CO2]/N are likely to be counterproductive with respect to plant growth in natural ecosystems due to CO2/N-induced shifts in plant species. So natural ecosystems may respond poorly to enhanced [CO2] due to water and nutrient limitation and species shifts. In other words the terrestrial ecosystem is likely increasingly to falter as a sink to "mop up" large amounts of enhanced anthropogenic [CO2]. Managed agricultural production will cope with enhanced [CO2] but is likely to become more expensive to support due to nutrient and water limitations. [*] J.A. Langley & J. P. Megonigal (2010) Ecosystem response to elevated CO2 levels limited by nitrogen-induced plant species shift Nature 466, 96–99 -
Baa Humbug at 20:35 PM on 1 July 2010What causes the tropospheric hot spot?
Hi David I'm sorry for the late reply. Firstly I wish to state that at no time have I commented to mislead people. If I have, it is inadvertant. Secondly I have 2 apologies to make. First, I have been using the term "hot spot" to mean a warming of the tropospohere and a cooling of the stratosphere. Maybe posting during the wee hours hasn't helped. I apologise for the confusion this has created. But with due respect, I have gone thru your previous comments and didn't find where you made this distinction until your last comment at #63 My second apology is to e who posted the RSS images at #57 In his/her comments he/she does clearly state the distinction. Both are my misunderstandings therefore my fault. Hope I didn't frustrate you too much. I'm not going to trouble you further until I resolve the following issues.. * The statement "Stratospheric cooling is the cooling of the stratosphere while the troposphere warms across all latitudes. This prediction is unique to warming from GHG's." made by e at#57. The charts presented by numerous organizations do not show warming across all latitudes for ghg forcing. They distinctly show warming at 30N to 30S at 8-10km aloft (yes along with stratospheric cooling) * The papers cited (Sherwood, Heimberger Titchner etc) go some ways to reconcile the radiosonde data with satellites, but by no means do they show the 2-3 times warming at the "hot spot" (accompanied by stratospheric cooling) * The ensemble of 6 charts we've been discussing. yes they are simulations from 1890 to 1999. This is the period man has been adding CO2 to the atmosphere. This is the period that has warmed (due to ghg's according to the IPCC). Chart C clearly shows a "hot spot" along with a cooling stratosphere. Therefore, our observations should show that. I don't believe they do. So again, like you, I look forward to future papers on this subject. Thnk you for your efforts. -
Paul D at 20:33 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Re John Russel @ 35... Interesting about the greenhouses. So if we give them CO2 at night and stick a load of lights on, we could stress them out. A bit like human problems caused by changes in daylight, sleep and work patterns. -
John Russell at 20:07 PM on 1 July 2010A Scientific Guide to the 'Skeptics Handbook'
An excellent little booklet, John; I will circulate it to all my sceptical friends. Just a couple of points. Having titled it "A Scientific Guide to the 'Skeptics Handbook'", it then doesn't mention what the 'Skeptics Handbook' is and therefore will confuse some readers who might come across it (one would hope) out of context. It would be good at the start to put a thankyou to Jo Nova for inspiring this handbook, plus a very brief explanation as to why the booklet was necessary (my tongue is in my cheek slightly -- but I'm serious). The other point is that some of the graphs are very low resolution. Would it not be possible to redraw them? The same applies to the UWA logo on the back cover.Response: Good advice. Have mentioned the Handbook on the inside cover as well as my authorship, which I forgot to put in the first edition. Have also created the PDF with higher rez graphics. It pushes the filesize up from 330Kb to 800Kb which is still pretty small.
For the record, when Wendy created the initial PDF, it was the proper resolution. It was only when I got involved in the process that the file went fuzzy. -
David Grocott at 19:38 PM on 1 July 2010A Scientific Guide to the 'Skeptics Handbook'
JC, Nova's actual assertion is:The greenhouse signature is missing. Weather balloons have scanned the skies for years but can find no sign of the telltale "hot-spot" warming pattern that greenhouse gases would leave. There's not even a hint. Something else caused the warming
The problem for Nova is that the tropospheric hot spot is not a unique 'greenhouse signature'. What is a unique greenhouse signature is the fact the troposphere is warming and the stratosphere is cooling. Note there is a difference between the troposphere at large, and the tropospheric hot spot. The existence of the actual unique signature is supported by strong observational data. Nova just gets very confused and conflates the two points. There is a good argument to say the 'hot-spot' has been found - see here and here - but it's absence would not imply that humans are not causing warming, it would imply that there is no warming - something which would be at odds with all of the surface and satellite data. With this in mind I find John's arguments fairly persuasive. The hot-spot is very much not as much of an issue as Nova would like to have you believe. -
Doug Bostrom at 19:18 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
By the way, John, I wasted a few minutes looking at Wittwer's "paper." It cites no references, none. The tract is riddled with political content, takes a wide excursion to discuss climate change, criticizes even Republican responses to the issue and claims that scientists "disagree on the likely effects of additional carbon dioxide on global temperature," carefully couched language indeed, technically true but conveying a powerful impression. It does contain the earliest occurrence of the term "alarmist" I've seen, dating back to 1992 as the item does. Is that where you're getting all this business about the life-giving properties of C02? -
Doug Bostrom at 19:05 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
doug_bostrom at 12:17 PM, doug you should take the opportunity to check back from where you shop and see where it leads to. No, John, I want you to provide us with evidence for your assertion that grocery store shelves are replete with fruits and vegetables grown with enriched C02. Where's the data? You know your way around this stuff. What's the market penetration, in percentages? -
werafa at 18:52 PM on 1 July 2010A Scientific Guide to the 'Skeptics Handbook'
John, You have done a good job, and please pass on our thanks to Wendy (behind every great man....) My big issue with climate change is our failure to present a compelling case to people not caught up in the debate. To often we do not balance precision with impact. so, once again thanks, and job well done -
werafa at 18:41 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
A brief explanation of the CO2 fertiliser effect from a Forester (I harvest my crop in 30 years so I have to know this stuff - and thanks for the comments because one never knows it all!) Plants combine carbon, water and sunlight to produce carbohydrate. That, along with a few minerals and trace elements is what is in your breakfast bowl, in your lunch box and will be on your dinner plate tonight. The CO2 fertiliser effect occurs where an increase in atmospheric CO2 concentration leads to an increase in plant production like adding dynamic lifter or super phosphate does. This is a good thing, right? Yes, it is a good thing, but it doesn't work well in reality. Plant production is ultimately limited by the "most limiting factor". This might be phosphorus, so adding super phosphate will give a boost to growth. If there is not enough nitrogen however, the plant can not use the added phosphorus, and adding the fertiliser is a waste of money. This is why farmers spend money analysing their soils. And what if water is the most limiting factor? You can fertilise all you want and get nothing in return. The majority of Australia's soils are nutrient poor, and receive limited rainfall, so guess what? Increased CO2 levels do have an important effect however, and there are indications that it is already happening. Plants open their stomata to breathe in CO2, and loose water in the process (stomata are the microscopic pores on leaves, and are a bit like a cross between sweat glands and lungs). If there is more CO2 in the air, plants don't have to open their stomata so much to get it, and loose less water. This means that they don't need as much water, which is lucky because over the last few years in Australia they mostly didn't get it. So what does this mean for climate change? Many places are expected to receive less rainfall over time, and plants need water to grow. An enhanced CO2 fertiliser effect seems likely to increase the water use efficiency and drought tolerance of many plants. Large scale Free to Air Carbon Enrichment experiments seem to indicate that original laboratory results are often not repeated in real world environments, and that what you see is what you get. But who is complaining. I think I will rather appreciate a bit extra drought tolerance in the future. -
johnd at 18:40 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
doug_bostrom at 12:17 PM, doug you should take the opportunity to check back from where you shop and see where it leads to. This paper may provide some historical background for you. It was written by SYLVAN H. WITTWER, professor emeritus of horticulture at Michigan State University. He directed the Michigan Agricultural Experiment Station for 20 years, and chaired the Board on Agriculture of the National Research Council. He is the author of the world's leading textbook on greenhouse vegetables, at least in 1992 when this paper was written. An extract from the paper to whet your appetite:- "American commercial greenhouses have used carbon dioxide fertilization for tomatoes, lettuce, cucumbers, flower and foliage plants, and bedding plants for at least 30 years. The benefits of this enrichment were first discovered by nurserymen in Germany 100 years ago, and the practice is widely used in Sweden, Denmark, Holland, Germany, Australia, and Japan, as well as the United States and Canada." Rising Carbon Dioxide Is Great for Plants by Sylvan H. Wittwer What I think is forgotten by many who are adept at Google searches and cutting and pasting, is that not everything is available on the internet. A lot of what I have read over the years comes from industry specific publications and describes what is actually happening in the real world. It may be years, perhaps never, that it makes it to the stage of being published in a peer reviewed journal and becoming available on the internet. But that doesn't stop the information being spread through the industry and being put into practice by those who are more interested by the practical results than any endorsement by academic experts. -
John Russell at 18:30 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
I did a bit of research into the way glasshouse growers use CO2 to boost plant growth. To simplify; as one would expect, CO2 levels in greenhouses fluctuate throughout the day as the plants 'breathe' both oxygen and CO2. It appears that higher concentrations of CO2 do help growth at certain times of the day when, in glasshouses, CO2 levels would sink below levels that would otherwise pertain outside in the open air. QUOTE: "The best time to add CO2 is from dawn to dusk. CO2 ranges from 400 to 500 ppm during the night due to plant respiration. Right after sunrise a level will drop to about 300 ppm. After three to four hours of early sun light it will drop to 100 to 250 ppm at which time growth will stop. If you add CO2 during the winter months when ventilators are closed and CO2 concentrations are low, you will get increased yield and bloom which normally happens during the spring and summer." The above quote is from Advance Greenhouses Perhaps the issue is not as straightforward as some people think. Modern plants have evolved to grow at their 'ideal' rates in the CO2 concentrations that have pertained in the atmosphere over the last 100K+ years. Increased CO2 concentrations can only affect growth in a useful way when plants are in artificial conditions controlled by humans and 'quantity not quality' is the human goal. Could wild plants subjected to increased CO2 levels become susceptible to other problems? For instance could too-rapid growth make them structurally weak and unable to support themselves properly -- so that they're more likely to blow over in a gale? Something like this might not matter in a greenhouse but it would matter in the wild. There's also the point -- hinted at in the quote -- that higher levels of CO2 could lead to inappropriate growth at times when the plant should be resting. This is OK for a greenhouse plant whose destiny is to be eaten -- not so good for a plant that needs to survive and reproduce in the wild. Yet another damaging effect of climate change. -
Argus at 18:25 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
A comment to #6 villabolo and #7 Bern: Animals and humans use oxygen primarily to get energy to keep us going through the day. Plants use CO2 to keep building biomass. They get energy from sunlight. Therefore it is more correct to call CO2 "food" for plants than "air" for plants. CO2 does not give them energy. -
John Chapman at 18:21 PM on 1 July 2010A Scientific Guide to the 'Skeptics Handbook'
Jo Nova still asserts that weather balloons have failed to find the hotspot and she produces a temperature map to support her case. How does a layman deal with one side that says balloons have found a hot spot and the other side that says balloons have failed to find a hotspot? BTW .. the guide is well produced and it went into the hands of most attendees to the WUWT tour. Lets hope they all read it. -
Marcus at 18:04 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Gallopingcamel, do you actually ever bother to *read* the results of these studies? Have a look at the results of one of their papers, where they find "...that elevated CO2 increased disease incidence and severity in two Cercospora leaf spot pathosystems in some years." So much for CO2 being a good thing. What is of far greater importance for tree growth is *not* CO2, but access to *WATER* & *GOOD CLIMATE*, neither of which were properly simulated in the FACE studies you refer to! -
Paul D at 18:00 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
The 'fallacy of exclusion' link doesn't seem to work. -
DLB at 17:54 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
About the only statement I agree with in this rather dismissive post is “the globe is not a controlled environment, and its incredible sensitivity to a variety of factors is something that is often (not considered) when such narrow arguments are proffered”. Using the same logic laboratory scale experiments on the effects of CO2 and temperature on coral and other marine creatures should also be assessed with a grain of salt (excuse pun). -
Doug Bostrom at 17:47 PM on 1 July 2010Sea level rise is exaggerated
Daniel, Donnelly interprets his data as offering -no- detail between 1300 to 1850, instead chooses as much as possible to smooth his interpolation by taking a linear approach, you propose that there may be detail therein. Who is more liberal in interpretation? We disagree and I don't think either of us is going to change our minds. -
ScaredAmoeba at 17:29 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Logical Science has a collection of studies onThe CO2 will fertilize the plants and increase food production meme. There is also additional scientific evidence for increased CO2 resulting in: a) Increased toxicity http://www.biolsci.monash.edu.au/staff/gleadow/docs/2009-clover-cg-co2.pdf b) Reduced protein levels Effects of elevated CO 2 on the protein concentration of food crops: a meta-analysis - TAUB et al. 2008 c) Increased toxicity and reduced nutritional value http://www.biolsci.monash.edu.au/staff/gleadow/docs/gleadow-2009-cassava-online.pdf -
tobyjoyce at 17:22 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
@galloping camel, I checked the website and the "F" in FACE stands for "forest". It is not clear if the results are transferable to large scale commercial growing of vegetables for consumption, where some key nutrients may be under stress. The video seems to show a replicated experiment where all factors except one (CO2) are kept constant, possibly at a generous level. Interesting, but a poor experimental design and too simplistic to be conclusive. -
Berényi Péter at 17:20 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
You may be interested in the Bookhaven FACE Research (Free-Air CO2 Enrichment) site. There is an extensive publications list there and also links to all the FACE research sites around the world. EuroFACE has a brief RESULTS page and lots of online publications as well. Explore, enjoy. -
daniel at 17:15 PM on 1 July 2010Sea level rise is exaggerated
Yes pete I know that we are focused too much on the one paper here. But I am not going to take the blame for that one (nor am I suggesting that you're blaming me). When I used the infamously inflammatory "utter joke" comment (and I apologise for the severity) I made it clear that I was saying as much considering the paper "on it's own" see for yourself #19. Others decided to take offence and make it part of the focus of the discussion. I just wanted to examine the papers cited by the article and show the poor quality of conclusions that can come from what is supposed to be "peer reviewed" climate science and how this kind of data is then used to support AGW to the public. I feel that there is far too much public trust in the quality of work, not just in climate science, but in the entire body of technical literature out there across all fields. The kind of ad hominem rhetoric above is being used as a debate strategy by proponents of AGW and it is simply not science. Can we please just discuss the data and the quality of conclusions drawn. It is extremely unconvincing (or should be) to anyone who works in a technical field to simply quote your qualifications and report a list of published articles. All this proves is that you are active in the field and fairly knowledgeable. But your papers can still be scrutinised by others who have been educated in distant fields but still have an understanding of (and can easily read up on) how the basic underlying principles (Math, Stat, Phys, Chem, sampling techniques etc.) are used to perform the work in your field and whether you have gleaned logically valid conclusions from your study. To adress your points from #39 in order 1) I believe that Gehrels et. al. 2006 cited in the original article tried to address the low resolution issue and even mention it in the paper. But I will go on to argue that this paper is another insight into the nature of the methods used in these studies which appear to be creating large height uncertainties, coupled with time uncertainties, that undermine any detection of short term recent trends (even with high resolution data). I'm not saying that any significant errors in the methodologies have occurred, just that the methods employed have too much uncertainty to detected the trends described. Please cite the papers and I'll try and get a hold of them. If these studies suffer from the same problems I see in Gehrels 2006 then I will most likely not be convinced of recent rapid SLR. 2) Yes this is a good point there needs to be a driver of SLR. But given that my confidence in the quality climate science is currently very weak due to issues like those in my complaints above then I doubt that my appraisal of the Grinsted and other SLR (or other) articles (that also investigate other factors like paleo-climate etc.) will be similar to yours. I fear I will find the same skewed conclusions I have thus far read in the two papers cited. I will need time to read the Grinsted paper and the reviews/articles you have linked to. Thankyou for those please let me know of any others you think are relevant. Doug, you may almost get my point on the Donnely paper. You said in #40: "Your entire thesis depends on deriving -more- interpretive detail from a data series you yourself claim has insufficient power to describe -less- detail." Donnely's thesis is actually guilty of claiming -more- detail through 1300-1850 AD than is actually detected. I am saying that it is largely unclear as to what short term trends may or may not have existed in that time. Therefore the final conclusion by Donnely et. al. based on the data they have provided (not counting sea level data from any other papers) was invalid and may be just the tip of the iceberg when it comes to the true state of the quality of climate literature. If this, seemingly popular, website uses these papers to back it's message of AGW then I fear what else may be going on -
gallopingcamel at 16:44 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
I have always had sympathy for plants as they have to survive with such a low atmospheric concentration of CO2. Concentrations have been as low as ~200 ppm but now are (mercifully) approaching 400 ppm. Then it struck me that fish are more deserving of my sympathy as they are trying to survive in water that always has less than 10 ppm of oxygen. -
gallopingcamel at 16:31 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
John Cook, I love you. Who else could find such comical stuff. Here is a nice little animation which I am sure most of your readers are familiar with: http://www.youtube.com/watch?v=P2qVNK6zFgE&feature=player_embedded Mariana, you will no doubt claim that this is a laboratory experiment with no relevance to the real world. Guess what? Duke University and NASA took the experiment out doors into the Duke forest in North Carolina: http://face.env.duke.edu/main.cfm The FACE experiment showed a dramatic increase in the rate of plant growth stimulated by CO2 until limitations in other nutrients kicked in. -
ScaredAmoeba at 16:28 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Oops 1988 typo! Should be 1998! -
ScaredAmoeba at 16:27 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
The CO2 is plant food dates back at least to 1988 with Environmental Effects of Increased Atmospheric Carbon Dioxide - ROBINSON, BALIUNAS, SOON AND ROBINSON [may be a little slow] of the Oregon travesty of a Petition.[Final Paragraph from this document] Human activities are believed to be responsible for the rise in CO2 level of the atmosphere. Mankind is moving the carbon in coal, oil, and natural gas from below ground to the atmosphere and surface, where it is available for conversion into living things. We are living in an increasingly lush environment of plants and animals as a result of the CO2 increase. Our children will enjoy an Earth with far more plant and animal life as that with which we now are blessed. This is a wonderful and unexpected gift from the Industrial Revolution.
I haven't yet delved into the references regarding this. -
Marcus at 16:25 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Yes, apescape, that would be the result of increasing drought, which is causing trees to grow less each year-in spite of warmer conditions & higher CO2 overall. Another nail in the coffin of the CO2 is plant food argument. -
CBW at 15:35 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Increased CO2 improves plant growth. Warmer temperatures mean longer growing seasons, which means more plant growth. Therefore, the midwestern U.S. in the 1930s, which had both warmer temperatures and higher CO2 than previous decades must have been great for agriculture. QED. Oh... wait... -
apeescape at 15:34 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Links appear broken. Also, I believe I remember a small controversy about some stunted tree growth of the past few decades... -
Marcus at 15:02 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Jim Eager-that's exactly my point. The FACE studies *only* replicate the increase in CO2, not the commensurate increase in warmth (which leads to a shorter growing seasons) & decrease in fresh water availability (increasing the likelihood of plant stress & reduced yields). Even without including these factors, the FACE studies have shown only the most marginal increases in overall yield, yet these same studies have shown a decrease in quality & an increase in the cost to produce it (due to increased demand for nitrogen). Like I said, John D's argument is looking pretty flaky about now! -
John Brookes at 14:57 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
I like the "CO2 is good for plants" argument. Especially when you put it alongside the "CO2 is present in such small concentration in the atmosphere that it can't possibly do anything" argument. However, I'm quite happy to concede the "CO2 is good for plants argument". Its pretty much the same as the "at least he made the trains run on time" argument for Mussolini. -
Eamon at 14:53 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
That should be "factors proportionately". -
Eamon at 14:52 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
The funny thing about this whole "CO2 is Plant Food!!!" malarkey is that the science showing it's rubbish is from the early 19th Century: Liebig's Law of the Minimum In summary: its no use increasing one factor which contributes to plant growth without increasing the other factor proportionately. -
AWoL at 14:14 PM on 1 July 2010CO2 is not a pollutant
Well thanks for the replies. Doug Brostron makes a good point in favour of government with respect to cholera in London. However, when governments get involved in commercial activity they invariably mess up. The Russian cotton industry and the disaster of the Aral sea and the dismal performance of collectivisation. But you're right, and I shall have to add public health to the short list of those things that governments are good at. Regarding the effect of CO2 on plants and particularly crops. I checked and indeed much of which you say is true, especially in already drought prone marginal areas. However northern latitudes are expected to benefit. At least in the short- term. There could be problems later, if temperatures rise......but only if temperatures rise.Unfortunately throughout most of those articles, the assumption is made that because CO2 is going up and temperature is going up, then the two are inextricably linked. Whilst there are warnings about a decline in seed quality, growers in Holland are pumping CO2 into greenhouses to obtain increased output in the order of 20-30%. Benefits fall off after 1000ppm and indeed higher levels are harmful. If anyone says, as I have done up to now, that plants can't get enough of the stuff, then that is indeed plain wrong. However I have heard it said, that it will be very difficult to get above 600ppm(atmospheric) even with no brakes applied to hydrocarbon consumption.True or false? So far I haven't come across any complaints about CO2 enhancement being a waste of time and money. If world output is going to be affected, water availability and temperature would seem to be bigger factors than CO2 levels. Obviously there are going to be changes, and winners and losers, but overall won't things carry on much as they are? Scaddenp makes the point about rapidity of change. An example or two, if poss please? Can't say I've noticed very much different here in Britain and the continent. Drought seems to be problem in Australia... but what's unusual about that? And while we're at it, where are the drowned deltas? I thought I was fairly well clued up on Geography, but maybe not. Maybe, when making a statement, you could provide an example or two? -
Bern at 13:51 PM on 1 July 2010Heat stress: setting an upper limit on what we can adapt to
Monckhausen, if you do a bit of digging around this site, you'll find some figures for climate sensitivity. As the numbers on that page point out, various estimates range from 0.9ºC per doubling of CO2, right up to 7.7ºC per doubling. The average (and most likely value) seems to be around the 3 to 3.5ºC mark. I can't comment on the other numbers given, but the fact that everything neatly lines up with factor-of-ten differences immediately rings alarm bells to me. Nature is rarely that neat. -
Jim Eager at 13:37 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Marcus, one more key question to ask: Q 6) Do the elevated CO2 trials also elevate ambient temperature commensurate with the test levels of CO2? A 6) No, they do not. -
Marcus at 13:28 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
So, according to my admittedly brief reading on the FACE trials, the yield gains from a doubling in CO2 are 5%-7% for rice, & 8% for wheat. Of course this takes no account for the potential shortening of growing times-or reduced rainfall-caused by global warming. Nor does it take into account the reduced protein yield that was shown in the Horsham trial, & previously shown by Ziska et al (1997). Seneweera and Conroy also showed-in 1997-that plants grown in CO2-rich environments show decreased uptake of both iron & zinc. Given that the Horsham trial also showed an increased demand for nitrogen by wehat, such a small increase in yields is not going to sell farmers on the "benefits" of global warming. -
carrot eater at 13:13 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
villabolo: I don't know if it's worthwhile or instructive to get into semantic arguments over whether a necessity counts as "food" or not. There are better things to worry about. -
adelady at 12:40 PM on 1 July 2010What is Global Warming and the Greenhouse Effect?
Anyhow. Back to the original idea. This is exactly the kind of explanation that will work with a non-scientific audience. And the more people in the scientific community who can come up with these ideas the better. Or talk them through with PR or advertising types who can simplify and condense complex messages, the easier it will be to have a more informed community. -
Marcus at 12:31 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Yet again you miss the point John D, its becoming an increasingly bad habit for you. Every time you bring up this issue, you fail to answer the key questions: 1) does an enriched CO2 environment generate long-term, increased plant growth in the absence of ideal conditions? 2) does an enriched CO2 environment generate a significant increase in the quantity of *edible* biomass (usually seeds or fruit)? 3) does an enriched CO2 environment generate a significant increase in the nitrogen content of the edible biomass? 4) does an enriched CO2 environment lead to a decrease in demand for other limiting factors (like fertilizer & water)? 5) does an enriched CO2 environment have any other positive or negative impacts on cropping *in the real world*? Based on the experiences of the farmers I work with, & the results of the Horsham trial you love so much, the answers to those questions are: 1) No. Improvements have been shown only in the short term, & only under ideal conditions. 2) No. In most cases only the vegetative biomass has shown significant increase, wheras edible biomass has shown no significant increase. 3) No, the Horsham trials actually show a significant decrease in plant protein yields. 4) No, the Horsham trials actually show that plants grown under enriched CO2 have a *greater* demand for nitrogen than plants grown under regular conditions. 5) Yes-increased CO2 is resulting in global warming which-in turn-is leading to a general decline in fresh water availability (Autumn rainfall in South Australia alone has dropped by 30% in the last 30 years). Increased CO2 will also cause increased vegetative growth in weeds, which will place further cost constraints on farmers in terms of weed control &/or fertilizer/water. So you see that your arguments really don't stand up to close scrutiny Mr D. Its also worth noting that the people that I encounter who are *most* concerned with Global Warming are the farmers I collaborate with-many of whom have worked the land for 30 years or more. If increasing CO2 in the atmosphere was so good IN THE REAL WORLD, then why are so many farmers having an increasingly tough time in maintaining a viable enterprise? -
jimbo at 12:24 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
I would like to add here that there is a need for a more information on the various photosynthetic pathways for various plants i.e. C3, C4 and CAM. Ultimately how elevations in CO2 can be positive in some instances and negative in others. The negatives being erratic growth of certain food producing plants, and the impact on biodiversity and ecosystem services associated with increased CO2. Anyone have any expertise in this field? -
Chris G at 12:24 PM on 1 July 2010What is Global Warming and the Greenhouse Effect?
#67, I believe you are correct - distance from peak to trough, or some harmonic thereof. Sounds right. -
Doug Bostrom at 12:17 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Perhaps the next time anyone visits a supermarket and salivates over the well grown fresh produce, and admires the beautiful flowers, just check out how much of what has been admired, or has been put onto your dinner plate in recent decades has been grown in an enriched CO2 environment. Drawing on your expertise, would you please produce some statistics on what we might expect in that department, John? Typically speaking, when I visit my grocery here on the West Coast of the US, what might I expect to see in terms of fruit and produce grown as you imply is common? Depending on the season we typically in a week purchase zucchini, celery, lettuce, tomatoes, potatoes, broccoli, onions, garlic, asparagus, apples, plums, peaches, bananas plus of course other vegetables and fruit. Of the foods I've named, what percentages would I expect to have been grown in enhanced C02 environments? -
Marcus at 12:14 PM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Wow, what an incredibly long post to say almost *nothing* of value John D. You keep banging on about how *wonderful* the FACE trials are in showing that increased CO2 is a good thing, yet the Horsham trials you rely on show that-even in relatively optimum conditions (in terms of water & nutrients)-there was no significant improvement in grain yield for most varieties, a significant decline in protein yield & an increased demand for nitrogen by plants grown in the enhanced CO2 conditions. As nitrogen is one of the biggest costs facing farmers, this hardly represents GOOD NEWS for the farming community-which is probably why the investigators themselves are so circumspect about their findings-especially given that they were starting to see acclimation just a couple of years into the trial. Given that CO2-induced warming is also expected to cause declines in rainfall, then the prospects for enhanced agricultural output in an enriched CO2 world are looking far grimmer than you'd have us believe. The fact, Mr D, is that until you're prepared to provide more substantial REFERENCES to back up your claims, then people will dismiss you as yet another denialist who gets all his (mis)-information from Monckton et al. -
johnd at 11:53 AM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
villabolo at 11:00 AM, I doubt that Monckton is the originator of the CO2 is food for plants "meme". The technique has been in commercial use for decades and is well understood by agricultural experts. It is only the focus on CO2 atmospheric levels rising that has over the last couple of decades caused them to conduct trials to see if what was being done artificially by commercial operators will be replicated under real world conditions. -
johnd at 11:44 AM on 1 July 2010CO2 is Good for Plants: Another Red Herring in the Climate Change Debate
Rather than simply taking the quick look at the science behind the argument as the author believes is all that is necessary, perhaps a detailed study of the real world, and the real world trials, such as the FACE trials, which are not mentioned, that replicate projected growing conditions, including enhanced atmospheric CO2, higher temperatures and lower moisture levels would be even more enlightening. Perhaps even looking at the results of trials that studied how plant growth responded to depleted CO2 levels would bring even better understanding as to the central role CO2 plays as a growth regulator. The arguments against increased CO2 being a positive for plant growth seems to be based on a belief that the current balance of inputs that plants require is optimum, each in the correct ratio. Commercial greenhouse growers know that that is not correct. Even if they provide sufficient warmth, nutrients and moisture, the full growth potential is not achieved until the CO2 levels are increased to optimum levels as well. Perhaps the next time anyone visits a supermarket and salivates over the well grown fresh produce, and admires the beautiful flowers, just check out how much of what has been admired, or has been put onto your dinner plate in recent decades has been grown in an enriched CO2 environment. The examples of the negative aspects only illustrate a lack of appreciation of the real world. What weeds in agricultural crops love even more than CO2 is nutrients, especially nitrates, and most cropped land has been stuffed full of nutrients. One of the biggest inputs into cropping is weed control, and any competent farmer is gradually reducing the weed seed bank, with genetic modification helping produce crop varieties that are more and more resistant to herbicides. Whether in the past, now or in the future, any farmer who has not overcome the weeds before the crop is planted will not be viable for very long. From an Australian perspective, over the last 50 years, the amount of cereals produced per acre has risen to nearly 3 times the previous level. It is anticipated that the same increase can occur again over the next 50 years even allowing for climate change. That means that the area of weeds that need to be controlled is dramatically decreasing for the same amount of food harvested. That seems more like a positive rather than a negative. As far as the supply of nutrients go, irrespective of any other factors, to produce more food, more nutrients are required to be put into the growing system, that is a basic truth. If the argument is made that the supply of nutrients will not allow the increased growth due to CO2 fertilisation, then there will also not be enough nutrients to support increased food production even if CO2 levels remained constant, or even fell. Being able to put more nutrients onto a smaller unit of soil to produce even higher yields is a positive both for efficiency of nutrient usage and application. OT a bit, but the biggest challenge is that for every 20,000kj per person per day that is produced in the paddock, only about 8500kj ends up on a persons plate. The more developed the society, the greater the wastage, little ever being returned to be recycled productively, huge amounts instead making it into landfill, decomposing to produce CO2 and methane. Lamenting over whether there will be sufficient nutrients to support increased growth due to CO2 is misplaced whilst such wastage is allowed to continue. The IPCC states that globally averaged mean water vapour, evaporation and precipitation are projected to increase, though there may be some shift in rainfall patterns. For Australia, in the areas where the rainfall is projected to decrease, the IPCC project a decrease in evaporation of the same magnitude if their Fig.10.12 is any indication. As for the wild fires, the argument is not even relevant, a red herring if ever there was one. Wild fires only present a problem when humans choose to settle in the areas prone to fire and build inappropriate infrastructure that is unable to be defended. Fires are a natural part of most landscapes, and where mankind is upsetting the natural cycle is not by allowing fires to burn, but by putting out the fires that would burn more frequently in less extreme conditions keeping fuel loads lower. This interference means that when a wild fire does start that is unable to be controlled, the higher fuel loads, and the fact that the conditions are generally more extreme, the results are even more devastating.
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