Hot Air Performance as a (Cost) Consideration for Flying and Future Aircraft

kolibri282

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The article below describes the impact of increased temperatures on flight performance and revenue for airlines, so it concerns almost all of us. For the builder of a recreational aircraft it might not seem to be that relevant, since you have more freedom regarding when and where to fly. Yet if you build your aircraft for the average weather conditions of the past it means that in the future you will either be grounded more often or you'll have to put yourself on a very dreary diet to bring down your weight....and there's a natural limit for that.........;-)
So you might want to add a little extra power to your project and (living in the relevant US danger zones) factor in some extra money to harden your hangar against exceptionally violent hurricanes which are bound to become much more frequent.

http://www.popularmechanics.com/flight/airlines/a27641/hot-weather-climate-change-flights/
 
In the seventies, the climatologists foresaw the beginning of a new glacial age, according the clear climate cooling from 1940 .
They proposed few solutions, such as by covering the Arctic ice cap with black soot, or diverting arctic rivers, but the governments leaders have not applyed them.
Here: http://www.denisdutton.com/newsweek_coolingworld.pdf
 
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Perhaps those scientists from the seventies would have been better off reading the article that had been published in the March issue of "Popular Mechanics" in 1912 where this piece of information was to be found: Screen-Shot-2016-10-26-at-7.17.17-AM.png








from here:

http://www.snopes.com/1912-article-global-warming/

the only thing he got wrong was that it didn't take a few centuries until the effect made itself felt but rather one, as this hurricane season with its unprecedented record in sustained category 5 hurricanes has shown.

The bottom line is: there are far sighted scientists and then there are others.....;-)






PS: I had thrown this sentence at Google Translate and got:
La seule chose à laquelle il s'est trompé, c'est qu'il n'a pas fallu quelques siècles jusqu'à ce que l'effet se fasse sentir, mais plutôt un, car cette saison des ouragans avec son record sans précédent dans les ouragans de catégorie 5 soutenus a montré.


which I think is damned good, the only error being that "car" should be "comme" like:


La seule chose à laquelle il s'est trompé, c'est qu'il n'a pas fallu quelques siècles jusqu'à ce que l'effet se fasse sentir, mais plutôt un, comme cette saison des ouragans avec son record sans précédent dans les ouragans de catégorie 5 soutenus a montré.

what do you think?
 
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If it is the combustion of fossil carbon that is responsible for the warming, then why it stopped for forty years from 1940, in full expansion of energy consumption?

PS: Yes, best translator is "comme" instead "car"
 

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The problem is that the climatologists got it wrong in 1912, as well as today. We, as a species, are very egotistical in our thinking that we have that much effect on air temperatures. The fact is that it is the sun that very much controls our planetary areal climate shifts.

What we have done, and are still doing is that by creating 6 billion tons of CO2 each year, we are acidifying the worlds oceans by truly measurable amounts. 1/3 of the CO2 we create has been continuously measured as taken up by the oceans, and converted into carbonic acid, the result of which has been to prevent the creation of shells by phytoplankton. Without this plankton, the seas food chains will starve, then die.
 
And I thought this was going to be resolved, Saturday the world was suppose to have ended,oh well maybe next time.
 
It would of course be nice, Jean-Claude, if you could explain every detail of a phenomenon, but this is actually not important. The one thing that matters is whether you get the overall trend right, and here our chap from 1912 did a remarkable job: according to the World Metereological Organisation fourteen of the fifteen hottest summers have occurred since the year 2000. (from here: https://www.theguardian.com/environm...global-warming ) and the reason why Hurricane Irma was able to stay a category five hurricane for several days, something not seen before in the Atlantic, are the unusual high ocean temperatures in the Caribbean so global warming is not a Chinese hoax as some people say.

As to acidifying the ocean Frank, you are of course right in that there are more good reasons why the use of fossil fuels should be stopped immediately but climate change definitely is one of them

PS: If you want to read a bit more about climate change and hurricanes have a look here: http://www.climatecentral.org/gallery/graphics/hurricanes-and-climate-change-what-we-know
 
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The climatological system that spans our planet is goverened by massively non-linear, intricately interdependent effects which are in turn influenced by a huge number of variables of which we have discovered a handful. Drawing far reaching conclusions and making sweeping statements, to me, seems very risky.

It is pretty uncontested that the prevailing climate is steadily getting warmer. The explanation why this is and the prediction how it is going to continue is on very shaky ground. Over the millennia the climate has always changed and rarely stayed constant for very long. It is due to our short life span compared to those over which the climate changes that gives us a slightly stilted view of things. We would like the climate to stay as it is now because that's how "it's always been". And that's what causes the least amount of problem for our species.

Whether the reduction of CO2 emission which we are -- rather unsuccessfully -- implementing has any appreciable effect on the currently prevailing global warming trend remains to be seen.

I am, however, strongly in favor of increasing our effort to reduce CO2 for three reasons:

1) As we don't really know how our CO2 emission affects climate, it is only prudent to minimize it.

2) As a species we have the obligation to use reasources responsibly as a matter of principle; global warming or no global warming.

3) Reducing CO2 stimulates us to become more creative and furthers technological progress, preventing us from becoming too complacent.

Greetings, -- Chris.
 
Nobody denies the warming trend, Juergen. It is just the cause by human activity is far from proven .
If this "detail" of forty years of non-warming is unexplained, then it seems to me that the warming trend is not explained either.
 
I fully agree with Chris, you would only be allowed to go on like you did in the past (burning fossile fuels, deforestation etc.) if you can give positive proof that this does NOT contribute to global warming. Since that proof does not exist everyone has a moral obligation to do everything to avoid possible contributions to climate change.
 
But the burden of proof lies with those who affirm that the climate change has something to do with human activity, something that hasn't been proved.
 
I'm afraid this notion is wrong, Javier. In court the onus of proof may be reversed if a case of especially dangerous and harmful crimes like e.g. terrorist, drug or child sex offences is heared. In drug trafficking as far as I know you are asked to prove that your possession were acquired legally, without using money made by criminal activities.

Now causing climate change is a terrible crime since you are affecting not only all people around the globe, think all the victims of the recent hurricanes, but even future generations. It is therefor up to you to prove you're not guilty.
 
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kolibri282;n1125151 said:
as this hurricane season with its unprecedented record in sustained category 5 hurricanes has shown.

Does this mean if we have a mild hurricane season next year, the earth is healing? The only thing having a series of strong hurricanes prove is that we had a bad season. Hurricane seasons are sometimes worse than others. Hell, back in 1900 a hurricane destroyed damn near every structure on Galveston Island. If I recall, 1900 was before the "industrial revolution". The only difference I see is how the media sensationalizes the storms more and more each year.
Now don't get me wrong. We are in an 'up-trend' of temps, but a 1/2 of a degree here or there is not the end of the word, let alone a problem to general aviation.
 
kolibri282;n1125181 said:
I'm afraid this notion is wrong, Chavier. In court the onus of proof may be reversed if a case of especially dangerous and harmful crimes like e.g. terrorist, drug or child sex offences is heared. In drug trafficking as far as I know you are asked to prove that your possession were acquired legally, without using money made by criminal activities.

Now causing climate change is a terrible crime since you are affecting not only all people around the globe, think all the victims of the recent hurricanes, but even future generations. It is therefor up to you to prove you're not guilty.

It's true that the burden of proof is sometimes reversed, for example in the labor courts here in Spain (and elsewhere), but stating that the reversal should be applied to the problem of the 'anthropogenic climate change' would mean to accept that that 'problem' really exists, something that hasn't been proved...
 
Does this mean if we have a mild hurricane season next year, the earth is healing?

Of course it doesn't, Bob, since it is just one piece of the puzzle. There are so many other facts that point in the same direction:

- earlier in this thread I quoted the World Metereological Organisation which states that 14 of the 15 hottest years on record have occurred since 2000
- glaciers worldwide vanish at an alarming rate
- several Pacific islands that were habitable for hundreds of years now are almost constantly flooded
- the west Arctic shelf ice became unstable a year or so ago and will now inevitably melt. This single event alone will lead to a sea level rise of three to four feet until the end of this century

you could go on and on. There is overwhelming evidence that the climate is changing and we are obliged to counteract that with everything we have. Ask the thousands of hurricane victims who stand in front of their ruined homes how many of them would advocate to just close our eyes and carry on the way mankind did in the past.
 
kolibri282;n1125220 said:
Of course it doesn't, Bob, since it is just one piece of the puzzle. There are so many other facts that point in the same direction:

- earlier in this thread I quoted the World Metereological Organisation which states that 14 of the 15 hottest years on record have occurred since 2000
- glaciers worldwide vanish at an alarming rate
- several Pacific islands that were habitable for hundreds of years now are almost constantly flooded
- the west Arctic shelf ice became unstable a year or so ago and will now inevitably melt. This single event alone will lead to a sea level rise of three to four feet until the end of this century

you could go on and on. There is overwhelming evidence that the climate is changing and we are obliged to counteract that with everything we have. Ask the thousands of hurricane victims who stand in front of their ruined homes how many of them would advocate to just close our eyes and carry on the way mankind did in the past.

Should we stop industry, driving cars, and farming land? Where do you draw the line? We could pic a date in history and strive to return the earth how it was on that date, but what date would we choose? Why don't we go back to the ice age? My point is that we have very little to do with climate change. If we were to go back to stone aged emission standards I'm not convinced the earth would cool. Climate change is real, but 'man made' , I wouldn't bet on it.
 
kolibri282;n1125220 said:
There is overwhelming evidence that the climate is changing and we are obliged to counteract that with everything we have.
Climato-skeptics do not dispute climate warming or rising sea levels. They simply dispute the human activity is the cause. Climate already changed much more in the past, when human activity wass less than that beavers.
 
Should we stop industry, driving cars, and farming land?
Of course not! There are alternatives to burning fossile fuels which will allow us to keep or even improve our standard of living in a sustainable way. Some US states are actually way ahead of Germany regarding the use of renewable energies. It would help if those would get more support. It would be possible to accelerate this development even more would that be made an all American issue like Kennedy did with the space program. A few hundred square miles of desert can provide all the energy used in the US today and modern high voltage direct current transmission allows to transport this energy to every point in the US, and this is just one of many possible ways towards a sustainable future!
 
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