Where is the Stratosphere today?

[TWCobra]

Advocates of Geo-Engineering state that any attempts at SRM must be made in the stratosphere. So where does the stratosphere begin? In the ICAO standard atmosphere that all pilots and meteorologists learn in Met 101, the stratosphere starts at the tropopause, which marks the height at which the temperature stops decreasing with increasing altitude (see lapse rate). In the ICAO standard atmosphere that point is just over 11 km-36,089 ft to be precise.

In the real world however there in a great variance in the height of the tropopause. So how can you quickly determine where it actually is on any given day? In a weather briefing given pre-flight to airline pilots, we are presented with a chart of significant weather along our route called the SIGWX. They can be found at this website.

http://aviationweather.gov/products/swh/
Updated version: http://aviationweather.gov/progchart

Clicking on the world chart will get you an area chart such as this.



The actual height of the tropopause in each region is marked in the rectangular boxes, one of which I have highlighted. You can see how the height of the tropopause is much higher in equatorial regions than in polar regions.

Here is the US chart for today which also illustrates that point. Also the positions of jetstreams are clearly marked.



One of the points of noting this is to see just how difficult it would be to spray anything in significant parts of the stratosphere. In most parts of the world it is too high for any large aircraft to reach. A 747 has an operational ceiling of 45,000 feet but cannot reach that altitude with any sort of load. I never flew one above 41,000 when carrying passengers and then it was right at the end of a sector with very little fuel aboard.

Anyway, now you know where to find the stratosphere over your place!

 

[TWCobra]

For anyone interested, the service ceiling of various large aircraft is as follows:
KC10 - 41,000 ft
C5-B - 36,000
C-141 - 36,000
C-17 - 45,000
A380 - 43, 000
767 - 43,000
A330 - 41,000
777 - 43,000

 

[George B]

For anyone interested, the service ceiling of various large aircraft is as follows:
KC10 - 41,000 ft
C5-B - 36,000
C-141 - 36,000
C-17 - 45,000
A380 - 43, 000
767 - 43,000
A330 - 41,000
777 - 43,000

Unlike ejecting passengers from your flight one can reduce weight as one would inject the aerosol such as SOx . . . some on ascent in the higher troposphere . . . especially near jet stream turbulence . . . would this not make higher cruising missions possible . . .

 

[Mick West]

There also seems to be also a more complex way of measuring where the troposphere ends and the stratosphere begins: Potential Vorticity. In this diagram the blue surface represents the tropopause as an isosurface (surface where a variable has a constant value) with PV of 1.6

http://www.fz-juelich.de/nic/Publikationen/Broschuere1998/umwelt-e.html

I don't entirely follow what it means though

 

[jvnk08]

Wow, very interesting. In reading other threads I saw mentions that the stratosphere begins at varying altitudes around the planet, but never really understood why. Thanks for sharing this.

Mick, very cool graphic. I can't pretend to understand fully either but it lends a much needed third dimension to the charts above in understanding just how much these things fluctuate.

 

[George B]

There also seems to be also a more complex way of measuring where the troposphere ends and the stratosphere begins: Potential Vorticity. In this diagram the blue surface represents the tropopause as an isosurface (surface where a variable has a constant value) with PV of 1.6

http://www.fz-juelich.de/nic/Publikationen/Broschuere1998/umwelt-e.html

I don't entirely follow what it means though

Seems the boundaries could be somewhat irregular . . . since Dr Minnis indicated persistent contrails are unlikely in the stratosphere . . . are some of the . . . on . . . off . . . on again . . . trails due to passing repeatedly across the tropopause . . . ??

 

[Mick West]

Seems the boundaries could be somewhat irregular . . . since Dr Minnis indicated persistent contrails are unlikely in the stratosphere . . . are some of the . . . on . . . off . . . on again . . . trails due to passing repeatedly across the tropopause . . . ??

Doubtful, if you look at the scale of the variations (see Europe in the image). It might be responsible for gaps in the order of many tens of miles, but not on-off - there's plenty of normal humidity variation that's responsible for that. See clouds.

 

[George B]

Doubtful, if you look at the scale of the variations (see Europe in the image). It might be responsible for gaps in the order of many tens of miles, but not on-off - there's plenty of normal humidity variation that's responsible for that. See clouds.

Well, an . . . on . . . off or off . . .on . . . situation would be possible, especially on ascent or descent . . .

 

[jvnk08]

Well, an . . . on . . . off or off . . .on . . . situation would be possible, especially on ascent or descent . . .

Perhaps, but Mick is correct in saying that varying humidity has more to do with "on off" contrails than the fluctuations described here. You must understand the distances involved in the graph are absolutely -vast-. Look at the portion of the earth beneath it, we're talking thousands of miles.

 

[George B]

Perhaps, but Mick is correct in saying that varying humidity has more to do with "on off" contrails than the fluctuations described here. You must understand the distances involved in the graph are absolutely -vast-. Look at the portion of the earth beneath it, we're talking thousands of miles.

I understand . . . but if the tropopause is in a more or less horizontal orientation and is an extensive consistent layer then what I said above is possibly true . . .

 

[TWCobra]

Unlike ejecting passengers from your flight one can reduce weight as one would inject the aerosol such as SOx . . . some on ascent in the higher troposphere . . . especially near jet stream turbulence . . . would this not make higher cruising missions possible . . .

A very lightly loaded 747 could get to 45000 with some load of sulphates... However... Isn't one of the tenets of your covert program that, for maximum effect it would have to be sprayed from equatorial regions? The 53000 feet we see in the chart near the equator is pretty much the default value. There are no large aircraft capable of flying at or above those altitudes. The SR71 and Concorde were the only candidates, both not particularly large and both retired with all copies accounted for.

 

[George B]

A very lightly loaded 747 could get to 45000 with some load of sulphates... However... Isn't one of the tenets of your covert program that, for maximum effect it would have to be sprayed from equatorial regions? The 53000 feet we see in the chart near the equator is pretty much the default value. There are no large aircraft capable of flying at or above those altitudes. The SR71 and Concorde were the only candidates, both not particularly large and both retired with all copies accounted for.

No it isn't . . . That is Jay's contention . . . I have suggest the northern latitudes or even polar routes . . . it is true the newest computer modeling suggests the aerosols would not stay in the stratosphere as long or be as effective; however, proposals as late as 2009 have suggested this approach . . . also, if such a program was engaged in . . . in the 1990s . . . they would use the aircraft available along with the operational limitations they possessed . . .

Can a Million Tons of Sulfur Dioxide Combat Climate Change?By Chris Mooney

http://www.wired.com/science/planetearth/magazine/16-07/ff_geoengineering?currentPage=all

The next question, of course, is how to get the particles up there. Various proposals have suggested using artillery, balloons, suspended hoses, military jets, or even converted 747s. Then there is the question of where to deposit the sulfur. There are different elevations to consider, as well as planetary location. A number of scientists, most recently Wood and Caldeira in a yet-unpublished paper, propose dispensing the gas over the Arctic — after all, that's where global warming is felt most powerfully and where cooler temperatures would help restore sea ice and stabilize Greenland.

 

[TWCobra]

Ok, must have misread it. I guess we are back to the "where - is - this - fleet - of - unaccounted - for - highly - modified - large - aircraft?" argument then.

 

[George B]

Ok, must have misread it. I guess we are back to the "where - is - this - fleet - of - unaccounted - for - highly - modified - large - aircraft?" argument then.

I don't think they thought the fleet needed to be that large . . .

Content from external source:




Cost Analysis Final Report
Prepared Under Contract to The University Of Calgary
Contract Number: __UC01-001______
Aurora Report Number: ____AR10-182__ October 30, 2010




http://www.agriculturedefensecoaliti...gary_Keith.pdf


http://www.agriculturedefensecoalit...2010_Aurora_Flight_Sciences_Geoengineering_Co st_Analysis_Final_Report_October_30_2010_AR10_182_ University_of_Calgary_Keith.pdf




2 Geoengineering Concept of Operations
This study focuses on airplane and airship operations to the stratosphere to release a geoengineering payload with the goal of reducing incoming solar flux. Airships are also considered for this mission. To provide a comparison to conventional aircraft opera- tions, more exotic concepts such as rockets, guns, and suspended pipes are also ex- amined.




For maximum cooling impact, the particulate payloads are best placed near the equator. This study assumes that the payload is released within latitudes 30°N and 30°S, though North-South basing location had minimal effect on cost. Transit operations, flying East- West between equally spaced bases around the equator, were examined as a method to ensure adequate dispersal of the payload around the equator. Global winds aid in East-West dispersal so a smaller number of bases and shorter range systems (referred to as Regional operations) can be employed with minimal impact on dispersal. Region- al operations allow the dispersal leg length to be dictated by the desired release rate of 0.03kg/m flown. This means the airplanes fly no further than they have to, on the order of 300-800 km, and fuel costs are minimized. Transit operations are not economical as the leg length is dictated by the distance between bases (for 8-base operations, legs are approximately 5,000 km) causing release rates to be low and fuel costs to be high.




A comparison of regional and transit operations utilizing Boeing 747s (at its service ceiling of 45,000 feet) is as follows:




x Regional: 747s operating regionally from multiple bases
o 14 airplanes, payload dispersed over 1,500 km cruise leg at a rate of
0.036 kg/m flown
o $0.8B for acquisition and $1B for one year of operations o 0.66M tonnes fuel burned per year




x Transit: 747s transiting from 8 bases
o 24 airplanes, payload dispersed over 5,000 km cruise leg at a rate of
0.012 kg/m flown
o $1.4 B for acquisition and $2.8B for one year of operations o 1.6M tonnes fuel burned per year




x Transit: 747s transiting from 4 bases
o 48 airplanes, payload dispersed over 11,000 km cruise leg at a rate of
0.005 kg/m flown
o $2.8B for acquisition and $4.5B for one year of operations o 3.24M tonnes fuel burned per year

 

[TWCobra]

A 747 is large.
.
And you are cherry-picking........

For maximum cooling impact, the particulate payloads are best placed near the equator.

 

[George B]

A 747 is large.
.
And you are cherry-picking........

Sure . . . it is best . . . I will not argue that but what is best is not always done . . . sometimes you do what you can do when a decision is made to do something . . . that is what I think possibly happened . . .

For maximum cooling impact, the particulate payloads are best placed near the equator.

 

[FreiZeitGeist]

A 747 is large.

And you are cherry-picking........

Sorry, Mr. George B, but you quote an over 70-Page "Article" (It isn´t a scientific Paper) from "Auroa Fligth Science", that is available here http://www.geoengineeringwatch.org/documents/AuroraGeoReport.pdf (PDF 4MB)

In this Article, they try to measure out how much a Airplane-SRM-Campaign would cost. And that there is absolutly no basic ground for trustfull Data. So even this avignaition-company has to speculate. And this is what they have done in this article....

.. so this article tries to calculate how much it would cost and did it worth it, and what are the Datas we´re have in Hand to calculate the costs...

And every time using this "cheapest" Variant in this "Article", they are warning, that some modificated 747 for the cheapest version doesn´t make the Goal- Because a 747 can´t fly high enogth to put the particles into the Stratosphere, where they can last for years and not just a week ore two to the next big rain washing all particals down

They put these Calculations with these Cheap 747s just for comparisment, because there is no real Data about "how much would this costs"

The Scenarios of this paper are not connected with real Geo-Engineering-purposes. It´s Data from Transport-Companies like "CargoLux" and small Arctic postal-flying-services. They have Costs and they delivering something. They made a Study "how much would it cost to make a "postal-Service with Geo-Engineering payload"...

And there cheapest option "rebuilded some 747" is cheap, just because the USA have some retired 747s from army-services and doesn´t have to buy them... No Cost for the "powers that be" to buy, but a many costs to rebuilt them for this purpose.

... The "Paper" itselfs prefers finally some special-build Airplanes, available to put some particles in the upper Atmosphere (exsepcially Straosphere) . In Dimensions like a Gulfstream-Learjet. These have the best Costs/Worth-Calculation...

(Please really sorry my bad english tomorrow. Just read the linked PDF relly in full, and I hope you´ll understand what I mean)

 

[George B]

Sorry, Mr. George B, but you quote an over 70-Page "Article" (It isn´t a scientific Paper) from "Auroa Fligth Science", that is available here http://www.geoengineeringwatch.org/documents/AuroraGeoReport.pdf (PDF 4MB)

In this Article, they try to measure out how much a Airplane-SRM-Campaign would cost. And that there is absolutly no basic ground for trustfull Data. So even this avignaition-company has to speculate. And this is what they have done in this article....

.. so this article tries to calculate how much it would cost and did it worth it, and what are the Datas we´re have in Hand to calculate the costs...

And every time using this "cheapest" Variant in this "Article", they are warning, that some modificated 747 for the cheapest version doesn´t make the Goal- Because a 747 can´t fly high enogth to put the particles into the Stratosphere, where they can last for years and not just a week ore two to the next big rain washing all particals down

They put these Calculations with these Cheap 747s just for comparisment, because there is no real Data about "how much would this costs"

The Scenarios of this paper are not connected with real Geo-Engineering-purposes. It´s Data from Transport-Companies like "CargoLux" and small Arctic postal-flying-services. They have Costs and they delivering something. They made a Study "how much would it cost to make a "postal-Service with Geo-Engineering payload"...

And there cheapest option "rebuilded some 747" is cheap, just because the USA have some retired 747s from army-services and doesn´t have to buy them... No Cost for the "powers that be" to buy, but a many costs to rebuilt them for this purpose.

... The "Paper" itselfs prefers finally some special-build Airplanes, available to put some particles in the upper Atmosphere (exsepcially Straosphere) . In Dimensions like a Gulfstream-Learjet. These have the best Costs/Worth-Calculation...

(Please really sorry my bad english tomorrow. Just read the linked PDF relly in full, and I hope you´ll understand what I mean)

I am fully aware of what a cost benefit analysis is (they used the only data available) and the limitations of the analysis quoted and cited above . . . there is from Rutgers University for example at least one proposal which suggests a similar approach . . . the question is were these limitations truly realized in the 1990s?? What we think now is not necessarily what was universally thought or understood when a decision to initiate geoengineering was possibly made . . .

http://climate.envsci.rutgers.edu/pdf/2009GL039209.pdf

 

[TWCobra]

....and here we go again....

 

[Jay Reynolds]

I wish George would stop this endless thread-hogging with his fantasy.

 

[George B]

I wish George would stop this endless thread-hogging with his fantasy.

Seems to me OP is making the point that large scale geoengineering isn't possible because of the service ceiling limitations of commercial heavy lift aircraft . . . I have shown in the literature cited here that is not necessarly a slam dunk . . . near polar injection of the stratosphere is and has been quite possible . . . if your objective is to limit the melting of the polar ice pack it is plausible . . .

 

[Jay Reynolds]

if your objective is to limit the melting of the polar ice pack it is plausible . . .

If your objective is to flog that jackass here until you create support for it, consider your progress over the past six months. You are not finding support when daily you derail even more threads. Maybe you need to flog it to the chemmies by making a website.
Murphy will put you in his next movie as a military insider and fame and fortune will surely follow. They will believe and your followers will be legion, guaranteed. It is clear you crave for people's attention about this George, but it isn't working out that way here for you, is it?

 

[George B]

If your objective is to flog that jackass here until you create support for it, consider your progress over the past six months. You are not finding support when daily you derail even more threads. Maybe you need to flog it to the chemmies by making a website. They will believe and your followers will be legion, guaranteed.
Murphy will put you in his next movie as a military insider and fame and fortune will surely follow.

I have no such motives . . . I could care whether you support my position or anyone else on this Forum . . . nor do I have any desire for a following . . . and I don't know most of the time who in the CT community you are talking about . . . I am here primarily because Noble challenged me to come to this Forum so if you want to blame someone for my presence blame him . . . LoL!!!

 

[Mick West]

The question then would be why do you stay? (Not that I'm trying to get rid of you, I'm just curious).

 

[George B]

The question then would be why do you stay? (Not that I'm trying to get rid of you, I'm just curious).

I think I enjoy the challenge . . . I see some benefit in practicing my debating skills and learning the strengths and weaknesses of my position and of my opposition . . . I have actually changed my original position very little from my research in 2009 . . . I am amazed at how little the positions on this Forum have altered my opinion. . . I never felt an injection program was visible nor could it be so for a covert program . . . nor do I believe those capable of such a program are NOT capable of maintaining secrecy . . . so most of your arguments here don't phase me . . .

I also believe one needs the loyal opposition to fully investigate and explain the logic of a significant position . . . if not challenged one begins to believe they know all the truth about an issue and becomes lazy and arrogant . . . I think I offer a service at some level here . . . LoL!!

Also, you think the government and its subdivisions are incapable of things I witnessed continually . . . they are incredibly capable, competent, efficient, and secretive when they need to be . . . In fact, it is institutionalized . . . we won't know for decades . . . or ever . . . many covert programs you have not even imagined . . .

PS . . . I also basically respect your hard work, dedication and offering an alternative to much of the nonsense on the Internet . . .

 

[AlexxJacobson]

I never felt an injection program was visible nor could it be so for a covert program (...) so most of your arguments here don't phase me

Even if a global covert program could maintain absolute secrecy over decades, it's effects should be measurable by now, right? The whole point of such a program would be having an effect, wouldn't it? This site has been an incredible resource to show you that this isn't the case.

many covert programs you have not even imagined

Is your evidence for those unimaginable covert programs as "strong" as for chemtrails, meaning no (un-debunked) evidence at all? How do you know about all this super-secret stuff if the agencies are so good at keeping secrecy as you claim?

 

[MikeC]

Unlike ejecting passengers from your flight one can reduce weight as one would inject the aerosol such as SOx . . . some on ascent in the higher troposphere . . . especially near jet stream turbulence . . . would this not make higher cruising missions possible . . .

Except of course you won't get to "spray height" with the full load in the first place, so you won't be lightening the SOx load untl you have burned enough fuel or you are carrying a reduced payload.

 

[George B]

Except of course you won't get to "spray height" with the full load in the first place, so you won't be lightening the SOx load untl you have burned enough fuel or you are carrying a reduced payload.

The difference is . . . because the destination may be very short and the ascent very gradual . . . . less fuel would be expended than on a typical fully loaded mission . . . and I would think a greater altitude could be reached for the relatively short mission . . . I realize more fuel is burned on take off and ascent but once at injection altitude little fuel would be needed for the return descent and landing . . .

 

[George B]

Even if a global covert program could maintain absolute secrecy over decades, it's effects should be measurable by now, right? The whole point of such a program would be having an effect, wouldn't it? This site has been an incredible resource to show you that this isn't the case.

Not necessarily . . . the idea is to have an effect but not be detected . . . there is simply no way to fingerprint the stratospheric sulfur that is presently found there as to source . . . if I designed such a program I would nudge the climate over several years and not risk catastrophic side effects and thereby risk detection as well . . .

Is your evidence for those unimaginable covert programs as "strong" as for chemtrails, meaning no (un-debunked) evidence at all? How do you know about all this super-secret stuff if the agencies are so good at keeping secrecy as you claim?

Are you doubting there were historical programs that we only found out because we were finally told . . . try Ultra decoding Enigma . . . http://en.m.wikipedia.org/wiki/Ultra

We were finally told about the Zinc Cadmium Sulfide injected over the US in 1950-60's in the mid 1990's . . .

 

[MikeC]

The difference is . . . because the destination may be very short and the ascent very gradual . . . . less fuel would be expended than on a typical fully loaded mission . . . and I would think a greater altitude could be reached for the relatively short mission . . .

If you load up a 747 to Max takeoff weight (MTOW) with passengers or SOx it is at MTOW in both cases. Therefore if it cannot get to "the stratosphere" with a full load of passengers and fuel it also cannot get there with a full load of SOx and fuel - the plane's climb performance does not care what the weight consists of.

therefore if you need to get to "the stratosphere" to spray SOx you have to be at less than MTOW in the first place - so less payload of SOx, or less fuel.

If you can offload a full load of SOx quickly enough then maybe you can takeoff with a full load of that ,and less fue,l and thus be at less than MTOW so as to get to the required altitude.

What are the design specs for the spray equipment??

I realize more fuel is burned on take off and ascent but once at injection altitude little fuel would be needed for the return descent and landing . . .

Indeed less fuel is burned in cruise and landing - which is prety much irrelevant since it is climb that gets you to "the stratosphere" and that depends on the weight carried.

 

[George B]

If you load up a 747 to Max takeoff weight (MTOW) with passengers or SOx it is at MTOW in both cases. Therefore if it cannot get to "the stratosphere" with a full load of passengers and fuel it also cannot get there with a full load of SOx and fuel - the plane's climb performance does not care what the weight consists of.

therefore if you need to get to "the stratosphere" to spray SOx you have to be at less than MTOW in the first place - so less payload of SOx, or less fuel.

If you can offload a full load of SOx quickly enough then maybe you can takeoff with a full load of that ,and less fue,l and thus be at less than MTOW so as to get to the required altitude.

What are the design specs for the spray equipment??



Indeed less fuel is burned in cruise and landing - which is prety much irrelevant since it is climb that gets you to "the stratosphere" and that depends on the weight carried.

Who said they couldn't reach the stratosphere in the more northern latitudes (31,680 feet, max ceiling at MTOW . . . 32,800 feet) . . . http://www.boeing.com/commercial/startup/pdf/747_perf.pdf

The stratosphere is situated between about 10 km (6 mi) and 50 km (30 mi) altitude above the surface at moderate latitudes, while at the poles it starts at about 8 km (5 mi) altitude.
http://en.m.wikipedia.org/wiki/Stratosphere#mw-mf-search

Is not the rate of ascent a factor . . . slower rate . . . less fuel used??? One usually tries to reach cruising altitude quickly for comfort and long range fuel efficiency reasons . . . both unnecessary with an injection mission . . .

Equipment specs are unknown . . . could be very complex or very simple . . . with oleum one only needs a low temperature heater and a hose to the exterior . . . pressure differential would force the liquid/gas overboard . . .

 

[TWCobra]

George.. Question. When the proponents of this sort of SRM mean the stratosphere, are they really thinking of the sorts of altitudes normally associated with the stratosphere or will any height do provided it is in the stratosphere of the day? What I am saying is, how effective would spraying be from lower altitudes? Serious question to you.

I am still trying to dig up 747 performance data. Getting to 45,000 feet in a 747 requires a seriously light aircraft. It was never a possibility with any sort of load. I will check with some friends of mine still flying it.

 

[MikeC]

Who said they couldn't reach the stratosphere in the more northern latitudes (31,680 feet, max ceiling at MTOW . . . 32,800 feet) . . . http://www.boeing.com/commercial/startup/pdf/747_perf.pdf

The stratosphere is situated between about 10 km (6 mi) and 50 km (30 mi) altitude above the surface at moderate latitudes, while at the poles it starts at about 8 km (5 mi) altitude.
http://en.m.wikipedia.org/wiki/Stratosphere#mw-mf-search

no one said it - but previous discussion was centered around doing so nearer teh equator, so a higher altitude required.

Is not the rate of ascent a factor . . . slower rate . . . less fuel used???

I dont' think so - the energy required to get to height "x" is a given - by taking more time to get there all you are doing is spending more time at lower altitudes where you are burning more fuel.

One usually tries to reach cruising altitude quickly for comfort and long range fuel efficiency reasons . . . both unnecessary with an injection mission . . .

Fuel efficiency is certainly a requirement for injection missions - every lb of extra fuel you have to carry is a lb of SOx you cannot carry and/or an increased and unnecessary cost.

Equipment specs are unknown . . . could be very complex or very simple . . . with oleum one only needs a low temperature heater and a hose to the exterior . . . pressure differential would force the liquid/gas overboard . . .

Of course pressure differential would force the material overboard - how else would it happen??

Without knowing what rate it is going to be pumped overboard you don't know how long your flight is going to be so how much fuel you can hypothesise carrying.

 

[Fred259]

Its understandable that you think this way but in reality if the aircraft climbs at a slower rate the time to the top of the climb will be greater. A slower rate of climb will actually burn more fuel as the aircraft remains in a higher density altitude (thicker air) for a longer period of time.


Other factors like outside air temperature and Mach number are also important. Also engines are designed to operate in a certain way; you cant just max them out like you do with the Toyota! If you do, its probable you will end up in a meeting without coffee and biscuits. That would not be good George would it.

 

[George B]

no one said it - but previous discussion was centered around doing so nearer teh equator, so a higher altitude required.




I dont' think so - the energy required to get to height "x" is a given - by taking more time to get there all you are doing is spending more time at lower altitudes where you are burning more fuel.



Fuel efficiency is certainly a requirement for injection missions - every lb of extra fuel you have to carry is a lb of SOx you cannot carry and/or an increased and unnecessary cost.



Of course pressure differential would force the material overboard - how else would it happen??

Without knowing what rate it is going to be pumped overboard you don't know how long your flight is going to be so how much fuel you can hypothesise carrying.

As far as location . . . Equitorial or northern latitudes . . . it could be a compromise motivated by cost and altitude ceiling limitation as well as an engineering decision . . . if the decision to slow polar ice pack melting . . . it was possibly the first choice . . . it also might have been decided to limit the time the aerosols would remain in the stratosphere . . . for fear of not being able to turn off the cooling effects in case a major volcanic eruption was to put 20 million tons of additional sulfur in the stratosphere like happened in 1991 . . .

As far as the rate of deposition . . . recent modeling has indicated the thinner the better . . . something like 1400 Km flight . . . however, older proposals suggested using cannon shells allowing normal high concentration to lower concentration dispersal to take place . . . which was hardly slow or spread thinly . . .

 

[George B]

Its understandable that you think this way but in reality if the aircraft climbs at a slower rate the time to the top of the climb will be greater. A slower rate of climb will actually burn more fuel as the aircraft remains in a higher density altitude (thicker air) for a longer period of time.


Other factors like outside air temperature and Mach number are also important. Also engines are designed to operate in a certain way; you cant just max them out like you do with the Toyota! If you do, its probable you will end up in a meeting without coffee and biscuits. That would not be good George would it.

Bottom line . . . Boeing says a 747 - 400 with maximum load can reach and cruise at 32,800 feet which is high enough to reach the stratosphere in the northern latitudes . . . http://www.boeing.com/commercial/startup/pdf/747_perf.pdf

 

[MikeC]

Bottom line . . . Boeing says a 747 - 400 with maximum load can reach and cruise at 32,800 feet which is high enough to reach the stratosphere in the northern latitudes . . . http://www.boeing.com/commercial/startup/pdf/747_perf.pdf

sometimes it will be, sometimes it won't - if you go back to the OP and look at the height given for the tropopause at the highest latitudes above the USA you will see it varies from Flight Level (FL) 270 (27,000 ft) to FL 340 (34000 ft)

 

[George B]

sometimes it will be, sometimes it won't - if you go back to the OP and look at the height given for the tropopause at the highest latitudes above the USA you will see it varies from Flight Level (FL) 270 (27,000 ft) to FL 340 (34000 ft)

Don't think that is much of a challenge to a sophisticated operation with access to the best predictive information and which according to at least one proposal need only operate about 270 days out of 365 . . .

 

[MikeC]

Don't think that is much of a challenge to a sophisticated operation with access to the best predictive information and which according to at least one proposal need only operate about 270 days out of 365 . . .

did you have a look at the size of the areas over which those flight levels apply? How often will an aircraft find it is in the wrong place - or alternatively have to carry extra fuel to find an area where the tropopause is low enough for proper "spraying"? I dont' know and I suspect you don't either, however it is yet another multiplier/difficulty that needs to be overcome to achieve the goal.

Edit: Having a look at the polar prognostic chart shows the entire polar area has a low tropopause FL220-270 - but of course to get there you have to fly from a 747-capable airport somewhere - shich will be essentially a major city in USA/Canada/Europe/Asia so you will need to be carrying essentially an intercontinental fuel load to do so.

 

[George B]

did you have a look at the size of the areas over which those flight levels apply? How often will an aircraft find it is in the wrong place - or alternatively have to carry extra fuel to find an area where the tropopause is low enough for proper "spraying"? I dont' know and I suspect you don't either, however it is yet another multiplier/difficulty that needs to be overcome to achieve the goal.

I am not saying you are not making good points but just like in a percentage of combat missions some are failures and have to be aborted . . . why would this be any different . . .