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Global Warming - A Health Warning

Posted on 19 August 2012 by Riduna

Let there be no doubt, global warming is a killer. It is likely to contribute to or be the direct cause of premature death because of the way in which it causes:

  • Loss of human habitat
  • Greater incidence of disease and
  • Increased ozone production

Loss of human habitat:

Most humans can only live in a habitat where very limited climate conditions prevail, where for most of the time it is not too cold (above 0ºC) and not too hot (below 35ºC).  Habitat that is wet enough to cultivate food yet dry enough to avoid prolonged high humidity.  Outside these conditions, we struggle to survive and do not live for very long.  Loss of habitat due to the effects of global warming poses serious threats to our survival.

Humans and, no less importantly the animal and plant species they depend on for food, can only cope with anything outside these parameters for a relatively short period.  The effects of global warming and the increasing speed with which it is happening is of immediate and longer term importance to humans.

Global warming produces climate extremes resulting in longer, more frequent periods of severe heat, drought, high winds, precipitation, tidal surges and flooding.  Such conditions pose a threat to our health and wellbeing, as evidenced by the 2010 heatwave which struck central Russia, destroying over 20% of the national grain crop and causing the premature death of some 50,000 people.  It is nearly certain this event would not have occurred in the absence of global warming.

Heatwave conditions result in a greater incidence of bushfires, accompanied by very dry conditions and high winds.  These contribute to contraction of human habitat since they limit reliable food production and water supply needed to sustain a population of any size, particularly very large urban populations.  The latter then become dependent on food imported from more distant areas where it can be produced and on water saved and stored from recycling, less frequent rainfall and desalination.

Examples of this are already evident in areas of dense population such as Perth and Melbourne in Australia.  These areas are trying to cope with populations growing at such a rate that increased demand is placed on dwindling local water and food supplies.  Be it the Central Valley of California or heavily populated N.W. India, sustained food production has become increasingly dependent on unsustainable pumping of groundwater because of diminishing availability of water from rainfall and glacier fed rivers.

Global warming is already causing land based snow and ice to melt much faster than it is being formed with the result that, apart from the Greenland/Antarctic ice caps and some mountain ice cover, the planet is likely to be largely ice free by 2100.  The consequences of this have been described elsewhere.

Suffice it to say that this is likely to result in average sea level rises of 1-2 metres by 2100, inundating low lying coastal lands and fertile river deltas inhabited by over 4 billion people, resulting in loss of land currently used for production of the food on which they depend.  It will only be possible to maintain food security by reducing exports or by importing more.

If global population growth is not curtailed, the presently low incidence of malnutrition will increase significantly.  This will reduce resistance to diseases, particularly vector borne diseases, which either do not occur or are rare at present.

Disease increases:

Global temperatures are already rising so fast that some species of plant and animal life have no time to adapt.  They face extinction or, at best, much reduced habitat able to support far fewer numbers.  For other life forms, rising temperature increases their habitat and this is the case for mosquitoes and ticks, both of which carry diseases and infect humans with them.

These vectors are currently limited to habitat in warmer, more humid parts - in Australia mostly in and north of Townsville on the east coast. They are rare or do not occur further south where winter temperatures fall to levels which kill them.  However, as ambient temperatures increase, mosquitoes and ticks will move further south or north and survive winter in places such as Brisbane, the more densely populated southeast corner of Queensland and then move south into New South Wales.

In a few decades from now disease carrying ticks and that harbinger of so many ills, the Anopheles mosquito, will spread to new temperate regions and bring with them serious diseases at present rare or unheard of in those places.

The following Table shows the more common of these, treatment presently available and prognosis for those becoming infected. As mosquitoes and ticks spread further south and north, they will bring diseases for which, at present, there is limited treatment. Many of these diseases either kill or permanently and adversely affect humans, particularly those with impaired resistance to them which, in temperate regions, is the majority.

Encephalitis, Dengue Fever and some forms of Malaria and Tuberculosis are particularly difficult to cure and often prove fatal.  Others, such as Asthma are rarely fatal if well managed but are exacerbated, becoming much more serious due to the presence of micro particles in the air caused by bushfires and dust-storms or worse, by an increase of atmospheric ozone.

While diseases causing diarrhea can be successfully treated, they weaken and disable those who contract them, usually from inadequately treated water but also from contaminated food.  For example, rising sea surface temperatures can increase the presence of vibrio cholerae found in fish and increase the likelihood of contamination in imported food. Children are more susceptible to cholera than adults and more likely to die without timely treatment. 

Sources:  WHO, Wikipedia and Encyclopedia Britannica

The World Health Organisation estimates that global warming is already responsible for 150,000 deaths annually and that half of these occur in the Asia-Pacific region.  Mortality will increase as temperatures rise and vectors spread to more populated areas.

A particular danger is posed by the Asian tiger mosquito, Aedes Albopictus, which is now present in the Torres Strait islands and Christmas Island.  It is able to survive in all Australian climates and is a dangerous vector.  Fruit bats are common in tropical areas but with global warming, their range will spread further south.  As carriers of the Nipah and Hendra viruses, they pose a special threat.

Increased Ozone:

Ozone is a molecular form of oxygen occurring at very low levels in the lower atmosphere.  It is produced from oxides of nitrogen (NO and NO2) and other volatile substances emitted into the air by vehicles, fuel stations and power stations every day of the week.  At present temperatures and in the presence of sunlight some of these oxides are transformed into Ozone, though seldom in such quantity that the ozone produced exceeds 40 parts per billion (ppb) for more than a few hours.

As global warming raises ambient temperatures, more of these substances are converted into ozone and its concentration in the lower atmosphere or troposphere rises.  This is one of the major reasons why we need to avoid an increase of more than 2°C in global temperatures.  However unless there is international agreement on significant reduction of greenhouse gas emissions the amount of ozone produced from these substances could increase ozone to dangerous levels in the troposphere.

We can not live without oxygen (O2) but we can not live with ozone (O3).  The presence of ozone in the troposphere in concentrations above 40 parts per billion near the earths’ surface is corrosive and toxic to humans, other air breathing animals and many food plants.

Ozone attacks the cells of the airway and lungs causing them to swell, produce fluid and fail in their ability to provide us with sufficient oxygen or protect us from diseases such as asthma caused by allergy and emphysema caused by smoking cigarettes.

If global temperatures rise more than 2°C, ozone concentration in the lower atmosphere is likely to rise above 100 ppb, a level dangerous to health. The effects on humans of ozone at various concentrations for short periods of up to 8 hours exposure are known and indicated below: 



Effect on human health


No ill effects evident but may contribute to asthmatics being somewhat less well



Those sensitive to ozone may experience slight breathing difficulty with increased rate of respiration, possibly slight pain caused by inflammation of lung cells.  May cause healthy people to become asthmatic or experience longer times to recover from influenza.



Healthy individuals may experience the above.  Those sensitive to ozone will experience reduced lung function evidenced by the need to take deeper breaths more frequently, some pain arising from inflammation of lung cells and more frequent coughing.  Asthmatics are likely to experience an increase in breathing problems.



Healthy individuals will experience pain from inflammation and other damage of lungs, be limited in level of physical activity, frequent coughing and soreness, congestion with phlegm and other fluids emitted by damaged cells.  Those with pulmonary complaints (emphysema, asthma, tuberculosis, etc) or heart problems at increasing risk of dying.  Those without them are at increased risk of developing them.  Children and young adults at highest risk of lung damage and dying.


What is not known for certain is the effect of exposure to higher levels of ozone on a longer-term or permanent basis.  It is reasonable to assume that those effects would be more severe than indicated at Table 2 – and fatal.

Increased concentration of ozone in the atmosphere must and can be avoided by reducing emissions from which it is made and curbing global warming.


Global warming is a very real health risk and one which is already beginning to affect us.  It can kill us all and will do so if allowed to go unchecked.  We know the risks, we know the measures required to limit them.  The choice is ours.

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Comments 51 to 96 out of 96:

  1. Sph, methinks the phrase 'not a True Scotsman' applies...;( Also, by this time in the dialogue, I believe the correct terminology is "will not grasp the concept." I've seen 'spoon-fed' and 'denial' on here before least *I* have learned a great deal about GLO that I didn't know before! If you wanna *trust* all them scientists, that is. {:-)
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  2. Dale @49: You reference the article, Ozone Layer Depletion - The Importance Of Stratospheric Ozone posted on the Science Encyclopedia by JRank. The operative paragraph from this article is: “In addition, some stratospheric ozone makes its way to the lower atmosphere, where it contributes to ozone pollution. Ozone is an important pollutant in the lower troposphere where it damages agricultural and wild plants, weakens synthetic materials, and causes discomfort to humans. During events of great turbulence in the upper atmosphere, such as thunderstorms, stratospheric ozone may enter the troposphere. Usually this only affects the upper troposphere, although observations have been made of stratospheric ozone reaching ground level for short intervals of time. On average, stratospheric incursions account for about 18% of the ozone in the troposphere, while photochemical reactions within the lower atmosphere itself account for the remaining 82% of tropospheric ozone.” Unfortunately, none of the statements made in the above paragraph are documented by source. I have absolutely no idea who wrote this article and whether or not the statements made in it are actually derived from legitimate scientific resources.
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  3. The CA Air Resource Board has a very good review of tropospheric ozone chemistry see Chapters 3 and 4 from which most of this argument is taken. WRT this thread there are a few important points to be made. First, while storm driven intrusions of stratospheric ozone can push ozone down into the troposphere, the penetration decreases as the distance from the tropopause increases. There are effects high up in the mountains but the amount that gets down to the ground is miniscule, esp wrt ozone in urban areas during the summer. For the purposes of this thread that is a red herring, a tasty one perhaps, but not more. Second, the discussion has not touched on the role of volatile organic compounds of both natural and man made origin, which are both key, but also complex. The effect on ozone depends on the ration of [VOC]/[NO2]. Starting with NO2 photolysis between 420 and 310 nm NO2 + hν --> NO + O (1) The oxygen atoms react with oxygen molecules O + O2 + M --> O3 + M (2) and NO is converted back to NO2 by O3 + NO --> NO2 + O2 (3) Following the air pollution board, in an unperturbed atmosphere the NO2 concentration will reach a steady state and from reaction 1 and 3 [O3]= k1/k3 [NO2]/[NO] (4) k1, the photolysis rate (which is higher in the summer), is much slower than k3 and normally there is more NO emitted than NO2, so under normal conditions not much ozone will be found Enter VOCs, which can convert NO to NO2 via RO2 + NO --> NO2 + RO (5) (R stands for any organic molecule) altering the balance in Eq 4 and more. The source of the RO2 are the VOCs. From both human and biological sources, this is strongly temperature dependent. Vapor from all sources (solvents/trees) is strongly coupled to temperature. For example consider Atlanta and the Appalachians. Atlanta has a world class tropospheric ozone problem because of the nearby Appalachians, which are primarily a pine forest. There is no major ozone problem in the Appalachians because there are no major sources of NO. In Atlanta traffic and industry produce a lot of NO, which interacts with the VOCs from industry and the Appalachians.
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  4. Gee EliRabett, there nothing like someone who knows what they are talking about to ruin a good argument. Thank you for that valuable insight.
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  5. Thanks, Eli! I've always said, it's good to have a spare chemist lying around, just in case you need one. And if you can find one that refers to himself in the third person, that's all the better! As an aside, here's more commentary (second hand, in the form of an article) from the UK Royal Society and a Guardian article from 2004. Both explicitly reference increased ozone levels and health impacts in this decade, versus previous periods. Impacts of climate change? You decide.
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  6. (-Snip-) EliRabett: Thanks for the info. Can you please describe the role of temperature (heat not light obviously) in the formation/destruction of tropospheric ozone? Sphaerica: Please point me to an actual peer-reviewed paper which supports the premise that GW increases tropospheric ozone formation.
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    Moderator Response: [DB] Moderation complaints snipped.
  7. Try B. P. E. Clapeyron, “Mémoire sur la puissance motrice de la chaleur,” in Journal de l’École polytechnique, 14 (1834), 153–190. If you have an open container of VOCs they evaporate exponentially faster when it is warmer. The original reference Eli gave IS refereed BTW and has many citations about the role VOCs play in forming ozone near the surface. Enjoy your reading assignment.
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  8. Dale, Climate Change, Tropospheric Ozone and Particulate Matter, and Health Impacts (Kristie L. Ebi1 and Glenn McGregor, 2008) Climate change and allergic disease (Katherine M. Shea, MD, MPHa, et al, 2008) Climate change, ambient ozone, and health in 50 US cities (Michelle L. Bell et al, 2007) A review of surface ozone background levels and trends (Roxanne Vingarzan, 2004) Is that enough (for now)? There are lots more. Lots.
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  9. Dale, in the face of the *mountains* of PR'd articles, cited references, and ~150 years of understanding of this subject, perhaps you might just do the right thing, and admit that *maybe*, juuust *maybe* you're incorrect about the stand you've taken? The hallmark of a *good* skeptic (nee scientist) is to know when they've been shown to be utterly wrong, and then "man up" and admit that mistake. We all do it, we all will continue to do it (Pauling eventually did it), and, at this point, it seems a bit--pointless--to keep answering your questions, when they've been addressed ad nauseum in this very thread. Just an idea...
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  10. I also would like to point out--not that the regulars here didn't notice it--that there's been a goalpost shift? Dale, we were talking *primarily* about the formation of ground level ozone (GLO), *not* tropospheric ozone. In any case, temperature there still is an impotant, if slightly less so, factor in its formation.
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  11. Dale, By the way, please do not take the next logical climate ostrich step, which would be to comb through those papers looking for statements that you can take out of context to make it look like this is not an issue. Please drop this. You are wrong. I don't expect you to admit to that, because it would change your level of ostrichosity, and I know climate ostriches hate to lose their very ostrichness. But the information is there. It's science. It is irrefutable. This debate is over.
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  12. "Ostrichosity".....scribblin' like mad, in my notebook..;) I also nominate the term, "ostrichoid,' for those who, even though they begin by sounding vaguely like true skeptics, start to lapse into full-on ostrichitis, when backed into a logic corner. I suppose it could also be for those who are beginning to get a clue as to the untenebility of their denialatti views, too. The lexicon grows....
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  13. Sounds like we need to declare PRATT and move on...
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  14. I second the PRATT.....
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  15. EliRabett & sphaerica Thanks for the links. I will look when I get a chance. But one question, why the continuous insults? Seriously, is it warranted or mature? Why do you do that? I missed it at 46, but just to point out none of those quotes actually say how temperature ends up causing more ozone. Is it the O2 + O process, then NOx process, other process or even simply because more air conditioners on. They discuss a relationship, but not what that relationship is. That is the question, does GW increase the O3 creation rate, or just it lead to more pre-cursors being available to potentially become O3. Also vroomie just to clarify, the article talks of tropospheric ozone, and so have I through this discussion. I've been very clear on that I thought. I will also state I've learnt a bit more too. I will return when I have done some light reading. (Excuse any spelling errors, its the tablet I'm on currently)
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    Moderator Response: [DB] It is important to point out and note here that Dale is objecting to the usage of the term climate ostrich, which he apparently feels is a pejorative. It is being used as an alternative to fake-skeptic or "skeptic" or climate-denier, and is used to describe someone adhering to agenda over science and evidence to the contrary.
  16. Dale, Because at comment 20 you disingenuously presented yourself as someone who was "just curious" when you clearly have an agenda and an unwavering position. Because at comment 27 you authoritatively presented incorrect information on chemistry in order to support your own beliefs, when you are clearly not qualified to do so. Because at comment 27 you used the exceptionally annoying and childish tactic of saying "I'm glad you agree" when I clearly did not. Because at comment 36 you resorted to the Gish Gallop technique (see today's post), again in an area where you really have no knowledge, just copying what you could from Google, just to continue to support a position which was by that point clearly wrong. Because at comment 39 you flat out lied about the content of the links I had provided for you, proving that your position was 100% completely and totally wrong. Because at comment 49 you used an amateur's interpretation of a Wikipedia definition to try to claim that NASA, the EPA, the IPCC, and all of science was wrong. Because at comment 65 you continue to distract and dodge and weave (now the problem isn't that the quotes don't say temperature, it's that they don't explain how, as if that makes all of those statements false and inconsequential), despite all of the proof that has been presented to you. Because after 4 days of discussing this, after having been decisively proven wrong, you still refuse to fess up. Because you are a climate ostrich, and climate ostriches are contributing to turning a seriously bad but manageable situation into a catastrophic and unmanageable situation through disinformation and delay.
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  17. Dale@65: You wonder why the insults? Dale@65: "Also vroomie just to clarify, the article talks of tropospheric ozone, and so have I through this discussion." Dale, on your first thread comment: "I've just spent the last hour looking into ozone counts around the world (as I'd heard it was a non-issue in relation to GW). I have to question Agnostic where that information comes from because there are plenty of papers out there showing no trend in ozone in various locations around the world (or a conclusion that no trend is detectable) for decades. Europe especially shows some regions where surface ozone has decreased over the last decade. The only conclusion I can make from looking at numerous papers is that since the mid-70's (when accurate recordings began around the world) it's clear there's no increasing or decreasing trend in surface ozone." What was the queestion, again?
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  18. To all.. Related to this latest in multitudinous references to ostriches burying their heads in sand (which they don't) and why it's such a useful metaphor, despite its inaccuracy, I'd *highly recommend a book, "Standardization or Error," by Vilhjalmer Stefasson. It speaks not only to the usefulness of untrue allusions such as the ostrich meme, but *directly* speaks to how ostriches, like Dale et al, cloud up otherwise clear issues. Standardization of Error
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  19. "It is important to point out and note here that Dale is objecting to the usage of the term climate ostrich, which he apparently feels is a pejorative. It is being used as an alternative to fake-skeptic or "skeptic" or climate-denier, and is used to describe someone adhering to agenda over science and evidence to the contrary." it. To that, I say...we calls'em as we sees'em. Similar to many of the earlier SkS threads, back in 2007/2008, when moderation was a bit more lax, this thread stands as a testament to the time--*now*--when it is important to use a bit more--ah, how to say this?--forcefulness, in calling out....*ostriches*. Personally, I use the term NOT as an ad hom, per se, but a clearly-understood, useful allusion to the exact behavior seen here, and in so many of the early threads. I think it is WAY past time to do so, and with that, I'll not go further OT. After having done a few days' intensive reading, it's pretty darned clear to me that: -Heat does contribute to O3 production, and; -Heat that stems from GW counts as heat, inconvenient as that fact may be to....ostriches.
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  20. I could of course use the term "denier," but that is deemed distasteful in some circles, what with the possible confusion with that Holo thing, so I'm trying to mend my ways.
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  21. "Fake-skeptic" is truly the best generic name. It is entirely accurate and faithfully descriptive. Considering that it is accurate, it is not pejorative. A pejorative is used to deride, not to describe. Fake skepticism is exactly what is at work here. Considering also the kind of appeal to torture and murder seen on certain blogs (such as Judith Curry's), I would say that even calling someone denier is rather mild...
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  22. And Dale, if you hac actually done more work before coming here and saying everybody else has it wrong, you'd meet a different attitude. Then again, if you had done the homework and applied true skepticism, your own attitude would be different...
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  23. To be fair, Philippe, a term can have both descriptive and deprecative content. Certainly it is no compliment to refer to someone as a 'denier' or even a 'denialist' in the context of climate science; however to call someone the former is to describe someone undergoing the psychological process of denial, and the use of the latter term is to describe someone who is engaging in the rhetorical techniques common to the various forms of denialism, without reference to what is being denied. But as long as the terms are being applied accurately, I do not think it reasonable for observers to focus on the deprecative element of terms such as these or such as 'fake skeptic' and attempt to dismiss the use of the terms on those grounds alone.
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  24. Composer@73, as long as the book, "Denialism" is out there, I have *no compunction* whatso-[self-snipped]-ever, using the term when I see someone comporting to the the well-defined actions that identify such behavior. Not speaking to their *character*, but rather, to their ~actions~. Fair deal.
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  25. Ah yes, FWIW since the 50s there have been numerous laws passed to limit surface ozone, and great technical progress in doing so. Now some, not Eli to be sure, might say that had something to do with the fact that ground level ozone has leveled off. Counterexamples can be found in any Chinese city. See Fallows, James.
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  26. I am surprised that my blog has attracted on-going comment and little if any of it related to the subject matter – effects of AGW on health. Commentary largely relates to the following statement: “If global temperatures rise more than 2°C, ozone concentration in the lower atmosphere is likely to rise above 100 ppb”. However this should be read in context. I am not asserting that ozone concentration near the surface will rise to >100 ppb but that if ambient temperature rises by more than 2°C, such an increase is likely. I accept that this claim is imprecise – deliberately so since I do not fully understand the complex photochemistry associated with formation (and destruction) of ozone in the lower troposphere. At comment 17, I tried to clarify that I was referring to regional concentration of ozone, noting that highest levels of O3 were to be expected where the precursors for it were highest. Elsewhere the blog refers to the harmful effects on health as a result of exposure for periods of 8 hours or more, so I am not talking about a persistent increase in O3 but a regional increase resulting in human exposure having adverse health effects. In some major cities there has been a trend to reduction in tropospheric O3 presumably as a result of public policy aimed at reducing the presence of precursors. In other major cities and surrounding areas, tropospheric O3 has been increasing and in some cases has exceeded 100 ppb. One should not be looking for a trend in the global concentration of tropospheric O3 but in the incidence of regional increase for periods of 8 hours or more. The IPCC reports (1) that there is a trend of regional increase in the incidence and frequency of dangerous levels of O3. Claims that It hasn’t happened yet despite an increase in temperature over recent decades (~0.6°C) does not appear to be a valid argument since (a) recent increases in temperature are still a long way from more than 2°C globally and (b) as noted above there have been regional increases for short periods where O3 concentrations have exceeded 100 ppb, levels that are harmful to human and some plant health, including food crops. An assertion made is that temperature does not affect O3 formation but given that the precursors include volatile organic compounds (VOC’s) the claim appears to be that temperature does not affect those substances. Yet VOC’s increasingly enter the atmosphere as ambient temperature rises(2). Rising temperature increases availability and reaction of O3 precursors to sunlight and both the volume and speed with which O3 is formed according to the Technical Appendix of Climate Change and Your Health(2). This is confirmed by the IPCC (3) and has been shown to produce harmful concentrations(4) of O3 in some regions. The chemistry involved is explained with admirable clarity by EliRabett at comment 53. 1. 2. 3. 4.
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  27. Composer99 @73, the word "denier" has been used in the English language since at least 1532 to mean "one who denies". It has never had any other meaning than that, either as to specific doctrine, belief or facts denied; or as to the psychological processes involved in the denial. It certainly does not derive its meaning form pop-psychology, nor from its very recent use to describe a particular form of denial. "Denialist" is a recent construction which I would consider far more offensive than denier, suggesting as it does that denial is some form of professional activity on the denier's behalf. My view on the use of the word "denier" is that: 1) Once you let a small group declare words off limits for political reasons, you have lost the battle with that group already, as they control the allowable forms of expression; 2) If somebody finds a word offensive, it is up to them to find a suitably descriptive, and non-tendentious substitute. I spent considerable time at WUWT at one stage encouraging them to do that, and it became quite clear that they generally insisted that the only acceptable word to describe them was "skeptic", with the implication that they held a virtue they patently fail to practice. 3) Finally, if a word is offensive because of the behaviour it describes (which appears to be the case), then the behaviour is itself far more offensive; so people who indulge in that behaviour have no grounds for complaint when it is accurately described.
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  28. I want to point out that I fully agreed with GW increasing the amount of pre-cursors ages ago. I also now accept that heat will increase the rate of the cycle. I'm going to write down how I understand it this morning, and feel free to comment, denigrate whatever. In the cycle of formation/destruction of ozone, heat speeds it up. However heat can't result in more ozone in this process (as in can't create more of something than the building blocks to make them). What heat does do however, is increase pre-cursors. But increasing pre-cursors doesn't translate literally to increased ozone. There's numerous conditions required for the ozone cycle to work which must be in place for the cycle to operate. Is that about right?
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  29. To first order on the [VOC]/[NOx] ratio
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  30. Dale, I don't understand how you can say "increasing pre-cursors doesn't translate literally to increased ozone." Yes, it does, hence all of the statements that increased temperatures (from GW) will increase ground-level ozone.
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  31. Dale, In actuality, if you look at Eli's equations, what you see is that VOCs facilitate the conversion of NO to NO2. This leaves less NO to convert O3 back to O2, which in turn shifts the balance towards increasing amounts of O3 (ozone). Everything (well, almost everything) in chemistry is competing rates of reaction. You have two (or more) reactions occurring in balance. In one direction you produce product, in the other product breaks down into reactants. When the system is in equilibrium, you have a concentration of products and reactants that is steady, because the competing reactions are balanced. If you unbalance the reactions (changing the rate in either direction) then the concentration of products changes as well. In our case, a reaction (dependent on temperature) changes the amount of one component of one reaction (the reaction that destroys ozone). This reduces the frequency of that reaction, thereby leaving more of the product of the other reaction (the reaction that creates ozone). The end result is more ozone with increasing temperatures.
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  32. Hot and cloudy. Hot and windy. Not every hot day will result in high ozone levels. For instance here in Melbourne it's quite common in late Jan-Feb for the temp to be 40C+ with up to 100km/hr northerlies. We know these as our worst bushfire days. So whilst extra heat will result in more pre-cursors, that does not translate directly to increased ozone.
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  33. Dale is entitled to his own opinion but not his own facts. And the facts on this thread are inconveniently against him. The ostrichicity is palpable.
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  34. What you are saying to me Daniel, is that heat will create more ozone. An analogy. 5 blocks in a row and you move the first one to the back of the line repeatedly at the same speed. If heat speeds up this process, then you repeat this cycle quicker. What you're saying is that if you add heat, not only does the cycle speed up but suddenly there are 6 blocks. If heat creates more blocks scattered on the floor, as you speed up the first to back block cycle the chance of picking up another block is higher. So through a combination of moving faster and more blocks scattered on the floor, the CHANCE of picking up another block in the line increases. But just because there's more blocks on the floor doesn't guarantee you'll actually pick one up. And, if you don't even start the first to back block cycle you can scatter as many blocks as you want on the floor and you'll never pick them up. So heat !== more ozone. Heat == more pre-cursors (as well as faster reactions).
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  35. "What is not known for certain is the effect of exposure to higher levels of ozone on a longer-term or permanent basis. It is reasonable to assume that those effects would be more severe than indicated at Table 2 – and fatal." No offense to you, but based on my experience as a guinea pig in the large scale laboratory experiment called the Los Angeles Basin in the late 1950's to the late 1960's, I would have to say it was not reasonable to assume any such thing. Let me refer you to a table put out by the South Coast Air Quality Management District: It doesn't present any data prior to 1976 ... but although I can't present any confirming data at the moment, I would bet you paychecks that ozone levels were considerably worse prior to the passage of the Clean Air Act in 1970, the oil crisis of 1973 and the mandatory installation of catalytic converters in the 1975 model year Even so you will notice that in 1977 and 1978, the maximum eight hour readings, averaged over a basin encompassing several hundred square miles, was over 300 ppb. The hourly average could go as high as 450 ppb. The number of days when a health advisory was issued (over 150 ppb O3) was roughly half the year, every year. How much of a "longer-term basis" were you looking for? Yet I see no evidence of drastic changes in mortality figures that correspond to those highs ... higher, yes, but marginally so. I suggest that you would see similar results looking at the populations of Mexico City and Beijing today, since they are dealing with similar ozone levels now. In short, without rather more evidence from mortality data in the public record to support your claim, I think that "[i]t can kill us all and will do so if allowed to go unchecked." is exactly the sort of alarmism that the ostrichocracy is forever whining about, and does your argument for major changes in public policy no good at all. P.S. Sphaerica@38 'Plethora', and its evil twin, 'myriad' should be avoided like an invitation to a James Inhofe barbecue. Not only are they grossly overused, they lack any precision, and convey to the reader the meaning "a whole shitload, and don't I have an impressive vocabulary?", making you look a pedantic twit.
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  36. "Be it the Central Valley of California or heavily populated N.W. India, sustained food production has become increasingly dependent on unsustainable pumping of groundwater because of diminishing availability of water from rainfall and glacier fed rivers." Another minor quibble ... farmers in the San Joaquin valley haven't been pumping much of their increasingly toxic ground water for about fifty years now. Water for irrigation is provided by the state and federal water projects, piping water from the Sacramento river and its tributaries several hundred miles south.
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  37. Old Mole, A quick Google gives this quote from a New York Times report on water use: "groundwater supplies in the Upper Ganges of India and Pakistan, the Central Valley of California and the North China plain are heavily overexploited, something that was already well known before". my emphasis The abstract of the study is here, but the article is behind a paywall. They mention only four aquifers in this part of the article and one is the central vally. Please provide a reference to support your wild claims that the central Vally aquifer is not overexploited. When you make unsupported wild claims like this people think you are just a troll. Please try to provide evidence to support your wild claims on the ozone thread also.
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  38. Dale has big trouble with AND. In the case of trop ozone one needs: Heat and Light and an Inversion because it closes the reaction vessel. If you have a lot of wind it dilutes the reactants. There is another role that VOCs play, but it requires NO2, to generate OH which oxidizes the VOCs to forms which can create more NO2. That mechanism is a bit more complex, but it too increases with temperature. Simple stuff first.
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  39. Dale,
    This has already been discussed (see inversions). I started out by stating that there are certain areas whose whether patterns lend themselves to dangerously high ozone levels (see comment 19).
    Heat == more pre-cursors (as well as faster reactions)
    Okay, I'll take one more stab at this. This is basic chemistry. First, your block analogy fails because there are far more blocks than one needs. Ozone (O3) levels are normally below 60 ppb. That's "parts per billion". The availability of oxygen (O2) in the atmosphere is 210000000 ppb. So you have 210,000,000 "blocks of O2" with which to build 60 "blocks of O3". There is no shortage of blocks, as in your analogy. Second, as I've already explained, everything is competing rates of reaction. If I can make ozone molecules faster than you can smash them, then the number of ozone molecules in the room increases. But it's not one person making ozone and one person smashing it, it's 210,000,000 million molecules of O2 per billion slamming into each other making ozone, and very, very few NO molecules slamming into those 60 ozone molecules and turning them back into O2. VOCs and other reactions turn more NO into NO2. This provides a lessened chance of breaking down O3 into O2, so your ozone smashing is inhibited (less NO mallets to go around). So if you add VOCs, there is less chance of breaking O3 down. If you increase temperatures, VOC reactions become more efficient, they remove even more NO, and the chances skew even further. Now here is the part you don't seem to get. In an atmospheric soup of billions of molecules, these reactions are happening constantly, myriad a plethora many times per second. Ozone is constantly being created and destroyed. How much ozone the atmosphere contains is a question of how fast all of those competing reactions are going. If ozone is being created more quickly, or is not destroyed as quickly, you get more ozone. This is all basic chemistry. If you cannot grasp this, you do not get a seat at the table. From here on out, I declare DNFTT (DNFTO).
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  40. 85, Old Mole, You are repeating Dale's and many a climate ostrich's favorite line of defense, "it hasn't happened yet in a noticeable way, so we don't need to worry about it, ever." That doesn't require any further discussion or rebuttal. It is the ultimate climate ostrich stance, and I will again repeat my favorite parable: A manAn ostrich jumps from the top of a skyscraper. Every time he passes an open window, he is heard to say "so far, so good." Oh, and you might want to go back and read the many, many myriad links that I have provided. A fair number of them directly refute your statements and position.
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  41. "Ostrichocracy." and the Great Myriad-Plethora Battle...this thread is not only informative, it's fun! To all who are arguing honestly (and I need not point out who isn't) thanks...I learn something new everyday. Sph...."DNFTO?" Terrell Owens is around, summweres?...;-)
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  42. Old Mole @85 Thank you for your referenced material which I note records the number of days per annum when 8 hour exposure to O3 concentrations exceeding 80 ppb (0.08 ppm) anywhere in the South Coast Air Basin. Table 2 in the blog refers to the effects of O3 concentrations up to 300 ppb and is then followed by reference to the effects of concentrations in excess of 300 ppb concluding that it is reasonable to assume that prolonged or permanent exposure would be very serious, indeed fatal. The material you cite substantiates that view and the dangers of ozone to human health, including the observation that concentrations of 200 ppb or more pose a serious health risk. I note in comment 76 that in some major cities there has been a trend to reducing O3 emissions as a result of public policy aimed at reducing emission of its precursors. Thank you for confirming that this is the case in California. You point out that the population of Mexico City are exposed to smog for protracted periods. However Mexico City is located at 1,800 – 2,000 metres above sea level. At that elevation climate conditions are not conducive to release of sufficient VOC’s to convert NO to NO2 which, on exposure to sunlight, is converted to ozone. While smog can be very heavy, concentration of ozone is unlikely to reach toxic levels for more than short periods – at present. However Guangzhou and other Chinese cities are at or close to sea level and have very polluted air including quite high levels of NO which has the potential to be converted to NO2 by natural and human VOC emissions. For this reason – and the fact that smog is by itself injurious to public health – Chinese authorities have embarked on retrofitting scrubbers to reduce industrial pollutants entering the atmosphere.
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  43. Old Mole @86 My comments on over-pumping of ground water in the Central Valley is based on a report in Geophysical Research Letters (1), a report by the University of California-Irvine (2) and related links as well as an article in New Scientist (3). I note that your comment refers to the San Joaquin Valley only and, while I am not familiar with geography of the area, my understanding is that this constitutes only a part of the Central Valley. (1) (2) (3)
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    Moderator Response: [Sph] Hot-linked links.
  44. Old Mole @ 85 claims that there is no record of premature deaths as a result of exposure to O3 in the South Coast Air Quality Management District. Sam Atwood, a spokesman is reported (New Scientist 25 August, 2012) as saying that in 2010, some 5,000 premature deaths occurred as a result of exposure to much reduced levels of O3. It is reasonable to assume that premature deaths were much higher in the past when O3 concentration was higher.
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  45. Eli strongly suggests that Agnostic use the google. There is plenty of VOCs in Mexico City due to, among other things very incomplete combustion from crappy cars and buses. They are starting to control the problem but it is wrong to say that ozone is not a problem, along with aerosols and NOx. They got it all, in spaced. Mario Molina has spent a great deal of time trying to quantify and help relieve the problem there. Use the google.
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  46. EliRabett - You are right. Smog is a problem in Mexico City and so is ozone, more so than I thought.
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