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(can of worms alert) Globe hasn't warmed in the last 16 years 76

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ScottyUK,
Not nice to make me spit my evening beverage all over my keyboard.

Greg,
Good points. I wish to hell we had successfully made them 40 years ago when fabricated "science" killed DDT (the safest insecticide ever developed) and R-12 (the most cost-effective refrigerant ever developed) on the alter of made up crap. You can wash peregrine falcons in DDT without harming them or their eggs, but some enviro crusader fabricated a study that blamed DDT for causing falcon eggs to thin. Subsequent studies refuting the initial study didn't get the media traction and never made a difference. Millions of people have died from malaria (or from cancers caused by the really nasty chemicals that replaced DDT) as a direct result.

R-12 was on the brink of making refrigeration accessible to a significant portion of the poor of the world. Then someone in a media outlet discovered a study that said R-12 was destroying the ozone layer and that we were all going to die of skin cancer. The "study" was a [very early] computer model that had failed to predict a single thing that it was looking at. All of the alternatives to R-12 require significantly more power input and significantly higher purchase cost.

The west's track record for providing ways for the developing world to leapfrog stages of development has so far sucked.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
 
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David

20 years ago I saw data about HCFs and ozone depletion and predicted decline and recovery if all CFC release was stopped. The predicted a continuation in degradation for a further 10 years then a turn around.

20 years later the large hole in the ozone layer in the southern hemisphere has repaired itself.

At the time I was close to this as I worked in reasonably senior management for the only company in OZ producing CFCs. We had to close our plant and retrench about 150 people as a result.

The information from our internal experts was

1) CFCs definitely seriously damage the ozone layer.
2) Different natural occurrence both damage and replenish it to differing extents at different times.
3) It is at least partly self healing as the extra UV light entering the upper atmosphere helps to form ozone.
4) Replacements had some serious shortcomings including lack of lubricity, toxicity, flammability and potential to explode and environmental and financial costs of manufacture.
5) That DuPont, who invented CFCs for refrigeration, chose to blow the whistle when they had a head start developing substitutes AND CFCs had become a commodity as all patents where expired.

I believe (ie think without hard data) that CFCs did the damage but it healed ahead of time as the self healing aspect was not considered by those with agendas.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &
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Pat,
You were a lot closer to the problem than I was. I was in graduate school when R-12 was banned and wrote a paper on the lack of rigger in the "science" presented. The reports I reviewed went something like:
[ol 1]
[li]In small scale tests (less than 50 L) CFC reacted with 100% ozone in a closed system {amazing since ozone is one of the most reactive substances on earth}[/li]
[li]There are places in the atmosphere where the ozone layer was thinner than in other places[/li]
[li]ergo, CFC is damaging the ozone layer and we're all going to die with our flesh rotting off of our bodies[/li]
[/ol]

I have never seen any data that definitively proves that the "ozone layer" actually filters UV (as opposed to being a reaction product of high energy UV waves and atmospheric oxygen), that is, I was never able to find out with any confidence if the ozone layer is a cause or an effect. Everything I studied made dire predictions based on micro-scale experiments and early-days computer models (the output of the models was boxes of green and white paper, the input was Hollerith cards). That really was the start of my skepticism about the way people were going to (mis) use computer models.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
 
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pat's point 5 suggests du pont's self-interest, no?

dave, do you have a report to support your DDT version. I agree that it is an extremely effective insecticide, capable of saving millions to peopel in the developing world from insect-borne disease, but understood that it had serious side-effects (ok, we can live without falcons, but what else ?)

agree with greg. raising the living standards in the developing world will be the significant economic growth for this century. it'd be nice to think that people could learn and maybe copying our current energy model isn't the best way forward. maybe an electric economy is "better". but copying is cheaper, and besides it provides the developed world with a dumping ground for the old technology. yes, i am a cynic.
 
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Yes my point 5 was a cynical reference to self interest.

Also I think it is extremely hypocritical on both international and individual levels for the wealthy to live a life of wasteful opulence while asking the dirt poor to give up any hope of a basic secure living and go without things like safe water.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &
for site rules
 
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Here is where I might make a statement about how Third World countries lacking clean water, usable roads, affordable enery and so forth is mostly due to actions of their own governments (such as they are) rather than actions by developed countries, but not today.

Regards,

Mike
 
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Pat,

"I believe (ie think without hard data) that CFCs did the damage but it healed ahead of time as the self healing aspect was not considered by those with agendas. "

This isn't quite correct. The estimates that I've seen are that if the Montreal Protocol is followed, then the ozone will be healed around 2050. And the self healing was considered when the Montreal Protocol was adopted.
 
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I've actually seen a few different estimates ranging from 2050 to the end of the century. So I picked the soonest date of the estimates I've seen. My main point, of course, is that it isn't back a pre-CFC levels yet and it is still repairing itself. I'm more than willing to put a large tolerance on that 2050 year.

 
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The internet has significantly shut people up thereby reducing CO2 emissions.

I'll agree that 15 years isn't enough. Neither is 142 years all things considered.

Pamela K. Quillin, P.E.
Quillin Engineering, LLC
 
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The methods of measuring temperature have changed over the years. Capturing the daily maximum and minimum temperatures was not so easy as it is now. The highest temperature on record from 1922 was recently refuted ( Until we have similar temperature sensing equipment collecting data for several years, the data will be questionable. Based on measuring errors, I would like to know if the modern low temperatures are also getting lower than the historical data.
 
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I only have data as told to me by our own well recognised experts from conversations around 1990. My memory is far from fallible and I never bothered to read the reams of data they provided as it was not my business unit involved.

I do believe the hole in the ozone layer is currently repaired which I believe is ahead of scheduel. Maybe I am confusing the scheduel for ozone hole repair with back to pre CFC levels. I think actual holes potentially over our land mass where more threatening to us in Aus than a general thinning to less than pre CFC levels. They where quite convinced that DuPont was behind the discovery.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &
for site rules
 
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"My memory is far from fallible" ... that's just boasting pat! but i think you forgot a prefix ? in- maybe ??

i'd comment on the typing but that'd be like people in glass houses throwing stones ...
 
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rb1957,
I'm on the road this week and my internet connection is spotty, but a quick look at Google found: Science Shame (see the second story on that page). USA Today. The Wikipedia article on DDT reads like an EDF publication and I'm not going to link to it.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
 
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thx david, i found eco-imperial.com ... stunning, surprising that if this is reasonably true then why hasn't the original ban been overturned ? too much vested interest ? (and not enough vested in the truth ?). next time my mother-in-law (who's a "birder") has a little too much "sauce" i'll bring it up !

and yeah, i know ... "you can't handle the truth" ...
 
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DDT is a useful insecticide, especially when used strategically, i.e. on bed mosquito nets. However, DDT wasn't used strategically in the 1950s: it was broadcast sprayed on cotton fields etc. The result was that most of the target pests developed DDT resistance. DDT itself is very low in toxicity, but DDT manufacture (inevitably) makes dioxins and chlorofurans which have known environmental effects at very low concentrations- known, not suspected, as the mechanisms by which they do their damage are understood. The same goes for pentachlorophenol, PCBs, and numerous other very useful 1950s chemicals- the problem wasn't so much with the pure compound as with the co-contaminants, and with what you get when you improperly dispose of them.

Total bans of materials such as DDT are actually dangerous: they put people's lives needlessly at risk. But it's very hard to put in place regulations with effect worldwide that allow proper, strategic applications of these compounds. It's also VERY hard to regulate the manufacture, use and disposal of these materials such that the truly harmful contaminants are either never produced, or removed and disposed of properly.

As to CFCs: the trouble wasn't in the use as refrigerants, where they were very useful and safe- it was the use as aerosol propellants, and in the venting of refrigerants into the atmosphere when the devices leak or are scrapped- something that can be reduced but not eliminated unless you stop using them at all. Chlorine atoms in the upper atmosphere catalytically destroy ozone, with turnover numbers in the 100,000 range- that too has been demonstrated by good, solid testing and is not in dispute. The reason CFCs were a problem was that these molecules were photostable enough that they needed hard near-vacuum UV- of the same wavelength range necessary to make ozone from oxygen- to photolyze, so they had the ability to survive the conditions in the lower atmosphere long enough to get up high enough to do their damage. The "self healing" of the ozone layer has little to do with the regeneration of ozone itself, which is of course happening all the time in the upper atmosphere- it has to do with the (low) rate of processes which remove chlorine atoms from the upper atmosphere once they're generated there.

As to CO2, we need to stop wasting fossil carbon as a fuel to the extent that we're doing now. We have nearly doubled the atmospheric CO2 concentration as a result of burning fossil carbon- that is a fact based on measurements. CO2 is a greenhouse gas- yes, that too is a fact- only the extent of its effect is in dispute. Its mass emission acidifies the upper layers of the oceans- again, fact, not in dispute except for the extent of harm that can be expected from it. These risks of harm are only two of many reasons to price fossil carbon for fuels use in such a way that we treat it as what it is: a precious, finite resource that is VERY difficult to substitute for in just about every other use we put it to OTHER than its use as a fuel. Most of the non-fuels uses for fossil carbon can be considered just as a "parking place" for the material: at the end of their useful life, they can be either recycled OR used as a fuel.


 
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Like Pandora found, it truly is impossible to close the box once opened. The most egregious of these self-serving, scare-mongering topics was Ralph Nader's "Unsafe at any Speed" condemnation of the Corvair. He had zero data and has since admitted that he even invented the anecdotes, but the Corvair is still the poster child for bad things coming out of Detroit. People remember sound bytes (which is why both parties rely exclusively on them in the current US elections) and few things are more damning than "I read that ...", the more outrageous the better.

An example that hit me in the face last week--I've always "known" that Congressmen and Senators received their full salary for life after serving one term. I know this. Everyone I know knows this. It is a cornerstone of our disgust at Congress. And it isn't true. A Congressman who gets elected to a 10th term and completes it (i.e., he has 20 years in the job) gets a 50% pension like any government worker. If he stays for more than 30 years he gets a 75% pension. No pension for 2 years. It is just an urban legend that everyone knows. With that kind of power of misinformation how do you ever get the DDT ban, the CFC ban, or the Carbon taxes to ever go away?

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
 
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