You imply that the Russians had to have US help in order to screw up so badly. They screwed up quite capably on their own. It would be nice if you would do a little reading, because these facts have been in the public domain for quite some time.
Russian government stole a US design
Wrong. The Soviet RMBK design (graphite-moderated, water-cooled) has no counterpart among US power reactors. The closest you could get would be the Hanford N reactor (not a power reactor) or an HTGR (cooled by helium, not water).
there are still good reason for leaving part of the spaceship in orbit. First is radiation shielding:
The proposals for Mars missions do not have much radiation shielding. Mostly because they can't carry enough to deal with cosmic-ray secondaries (the products of cosmic rays hitting matter in the spacecraft and creating showers of lower-energy particles that are more damaging than the original). What you want is a thin hull just sufficient to stop solar X-rays and low-energy photons; for solar flares you retreat to a "storm shelter" shielded by your food, water, equipment etc. that stops the solar protons and tolerate the increased dose from cosmic-ray secondaries (which aren't as plentiful and won't cause an acute problem over the duration of a solar storm). To fully stop cosmic rays takes about ten feet of dirt, which is far too heavy for any mission being contemplated.
It might make sense to leave the engine in orbit because it's useless on the surface
You're assuming it makes sense to have two return engines at all. Leaving aside the problem of ensuring that the orbiting engine is still working after your surface mission, that engine has to justify itself. Consider the methane-oxygen engine at 375 sec, vs. Mars' escape velocity of 5.03 km/sec; the required mass-ratio is 3.9. To get to Mars orbit the mass-ratio would be
2.63, not a lot different. You are also adding the mission risk of the rendezvous (which kills you if it fails), and complicating the mission hardware with yet another set of engines, power supplies etc. that have to be developed and tested.
I can think of one thing that might justify such effort, and that is a solar sail which would help pull the crew return vehicles to Mars and then return to Earth for the next. This could reduce the fuel requirements for launching a CRV to that sufficient get to an orbit a few thousand miles up, rather than Earth escape velocity; the improvement in mass delivered to Mars might be sufficient to make it worthwhile for second-generation missions.
Then humans land, do their thing for a while (two years?) and get in the launch vehicle and go up to the orbiter.
Orbiters are the way you get to impossible budgets, schedules and difficulties; you really want to land everything and depart straight for Earth on your trip home. See this post for a short summary why.
The escape velocity of Mars is 5.03 km/sec (thanks to Acidic Diarrhea for the link). The velocity required just to get into Earth orbit is ~8.0 km/sec, and Earth's atmosphere is quite a bit more difficult to deal with.
5 km/sec is about 11,200 MPH. That's not even enough to make a good ICBM on Earth, but it'll get you completely off Mars. It is pretty obvious that we have had the rocket technology to get back from Mars for a long time, and getting back is much easier than getting there in the first place.
One of the things people keep claiming is that it's necessary to leave a return vehicle in Mars orbit. This is exactly how NASA got the $400 billion figure for a Mars mission; it is a huge mistake. Landing everything instead of leaving it in orbit has terrific advantages:
You can aerobrake your entire mission instead of having to insert into orbit with rockets. This eliminates the mass budget for the fuel.
You can manufacture your fuel supply for the return voyage from Martian atmosphere, instead of having to carry it with you. This buys you something like a 12:1 advantage.
You avoid having to rendezvous with an orbiting return vehicle to get home; if you cannot rendezvous, you're dead.
You avoid leaving your return ticket in orbit where you can't maintain or protect it, with its precious fuel in tanks which can be punctured by meteoroids, etc.
Not even NASA wanted to leave an orbiter for it's own sake after seeing Mars Direct. Zubrin has that much right.
the skill mix we need to send to Mars has to include a couple alchemists?
Apparently not. A lab-scale plant to make fuel from simulated Martian atmosphere was built by Robert Zubrin and an assistant. Zubrin is not a chemist, he is an engineer.
You can get a PDF of some of his later results here.
I've given my foes a -2 karma penalty. This puts my foes (currently, you and you exclusively) below my default threshold unless someone mods you up.
Again, nothing personal; this is part of attention-management. What I read is my business. How you react to what I decide to read is your problem, not mine. If you choose to waste your time writing flames I'll probably not see except as a response below my current threshold, it's your life (or lack thereof).
you've already admitted that logic and reason is not the purpose of the "Uma Thurman" posts.;)
Yep, I think you've got it surrounded.
Okay. As a consequence, I'm giving you an exclusive spot on my "foes" list. Not because I care either way about your politics, but because I think there's no point in reading illogical, unreasoned rants directed at others.
The forests in question are in Indonesia, where peat bogs full of old trees are first cut for lumber and then partially drained and planted as plantations. Drying out the peat makes it very susceptible to fire, which releases huge amounts of trapped carbon.
I bet you cringed when it was a liberal administration...
It's a made up definition of liberal, provided by people like Rush Limbaugh and Ann Coulter. And if you buy into that definition, you're being fooled.
Really? According to the Washington Times, Anthony Williams (the then-mayor of Washington DC) is black, as is 60% of the city. He's also a Democrat. Blacks also have a history of voting strongly to the left of the political spectrum, so if the Williams administration is not "liberal" in the political (not economic or charitable) sense of the term, what is it?
Also, I'm not ragging on "people". I'm ragging on the demonic right-wing swine that signed up for my abuse list. I'm polite to everyone else (those not in my freaks list.)
Interesting. You admit that the rants you post under this account are not intended to be logical, persuasive or anything but abusive, but someone who finds them not worth reading and puts you on their foes list so they can knock them below their default threshold is ipso facto a "demonic right-wing swine"?
I'd ask you if this isn't faulty logic, but you've already admitted that logic and reason is not the purpose of the "Uma Thurman" posts.;)
I recall reading some years ago that the forest/peat fires in Indonesia (which created a pall of smoke over much of the region and reduced visibility to a few feet over wide areas) dumped more CO2 into the atmosphere than all of the vehicles of Britain in the same year. Here's a paper which cites estimates of 0.6 to 3.5 gigatons from the 1994-5 fires and a similar figure for 1997-8.
Just goes to show that Kyoto isn't the solution, because it ignores emissions by "developing countries" regardless of origin.
Y'know, "Uma", it is one thing to rag on people who spout unthinking radical-right rhetoric (look, I alliterated!). It is a very different thing to post mindless and off-topic attacks against people who cite real examples of abuse from their own lives.
Besides, I bet you cringed when it was a liberal administration which tried to fire someone for using the word "niggardly", while the poster's experience sounds more like an embar-ass-ment of the right because a leftist isn't going to get bent out of shape for a three-letter-word.
Last, the pathetic state of knowlege of those who obtain teaching certificates is widely known, irrefutable and of no particular help to either side of the political spectrum.
It is difficult to conceive of a literate person in this day and age who would not know that "aster" and "asterOID" are two very different things. It's difficult to think of anyone in media who wouldn't have some idea about this either, after the films "Armageddon" and "Sudden Impact" just a few short years ago.
The person who let that piece be printed in that form deserves to be the laughingstock of the science-editor community from now until he leaves the business. There is no excuse for getting high-school-level science facts wrong.
The RFID tag is separated from the meat when the hide is pulled off, no? At that point the meat becomes un-tagged, and if testing takes long enough that people eat the meat before the test results come back the "protection" goes to zero. Do you really have any idea where the results of "advanced meat recovery" go once they're scraped from the skeleton? They could be in any number of patties, sausages and pot pies.
I hope that bar-coding can be used as an alternative to RFID for the small farmer, so that e.g. grass-fed operations can stay in business without having their costs driven up by the less-safe factory farms.
While I agree with you about nuclear, I have brontosaur femur-sized bones to pick with some of your other claims:
Wind: Nonviable (kills birds, not cost efficient.)
If you've looked at the price curve of wind power, it is already cheaper than fossil fuels with current tax incentives. Further, the industry is still gaining experience and turning it into new units which cost less per watt and produce power cheaper. The result is soon to be wind turbines which are cheaper than fossil without tax incentives. I favor incentives to keep the production up so we get there sooner (solar-thermal was snuffed prematurely by a sudden loss of tax incentives, google for "Luz" for gory details).
Solar: Nonviable (cost of production exceeds energy consumed, massive chemical waste byproducts)
Solar is quite viable and compares very favorably with the cost of extending utility service for more than a fraction of a mile. The energy cost of a solar panel is repaid within 2-5 years; the estimated useful life is upwards of 25 years.
Coal and gas: Viable (unless you believe in global warming, which most "greens" do)
North America is rapidly running out of gas (to the point where Alan Greenspan has noted the need for CNG terminals to import it from overseas lest shortages clobber the economy), and coal emits so much nasty shit in the form of sulfur and mercury that it is not usable without a complete overhaul of the technology; for instance, pulverized-coal combustion boilers have got to go or we won't have edible gamefish due to methyl mercury contamination.
Conservation: Nonscalable. Cut your energy consumption by 50%? Sure. But 50% of O(N^x, where x > 1) is still going to present you with unacceptable constraints on growth.
If you start stacking conservation measures (insulation, daylighting, complete replacement of incancescent lighting with fluorescent or better, hybrid vehicles) on top of local/alternative production (e.g. wind, microhydro, local concentrating solar) the remaining demand starts to look like something we can handle with fuel derived from crop byproducts or municipal refuse. If we ever get something like the ten-cent-a-watt solar film that was touted earlier this year, the cost of energy is going to fall so much that fossil fuels are just going to be left by the wayside, as spermaceti died after the development of the kerosene industry.
steadfastness: they have been working on UnixWare since before SCO became a legal bully, and since they have nothing to do with the top management or legal shenanigans they feel that they are doing the right thing by continuing to support SCO's software vendors and customers.
This is not to say that looking for a new job isn't a good idea, but someone who finds themselves writing UnixWare code for the Canopy Group through no fault of their own is not morally obligated to jump ship until they have another ship to jump to.
The point is that there are already commercial operations that do achieve these numbers. They do so in order to provide a valuable service: placing satellites in orbit.
Is there any commercial operation which offers manned suborbital flights at all, let alone inexpensively and flying a fully-reusable vehicle which can be re-flown in two weeks or less?
I have not heard of a commercial (or government, for that matter) effort to fill any one of those niches, let alone all of them.
Thus your comments on 200 mile orbit and acceleration are not relevant.
Nice attempt to back-pedal and change the subject after being proved wrong, but given that you now say the corrections are irrelevant you beg the question of why you made such blatantly wrong assertions in the first place.
Altitude alone is not especially useful since the pull of gravity will still exert its force upon the craft.
Wrong. At a not-atypical 200 mile orbital altitude, Earth pulls with roughly 90% as much acceleration as at the surface. The difference between an orbital flight and a sub-orbital one is that an orbiting craft moves fast enough that the curve of the earth falls away below it as fast as it falls toward the earth.
The hard part about space travel is achieving orbit, a state where the craft has effectively escaped the earth's gravity well.
Wrong again. The gravitational binding energy per kilogram is given by the simple equation -GMe/r, where G is the gravitational constant, Me is the mass of the earth and r is the distance from the center of the earth (taking Earth as a uniform sphere, which is good to a first approximation). You can trivially compare this to the kinetic energy of a craft in a uniform circular orbit (v^2=GMe/r^2, ke = 0.5 m v^2 -> ke =.5 GMe/r^2) and prove that orbit is only halfway, energetically, to actually escaping Earth.
Geosynchronous orbit...
has what to do with this, exactly?
These numbers are better than order of magnitude higher than the X-prize requirements.
So I wonder if the X-prize is really meaningful in the scale of realistic space flight?
Google for "Black Colt" or consider what the White Knight could do with a sub-vehicle like a Pegasus. That will let you ask better questions.
... was not a turboprop. Both the front and rear engines were rather conventional opposed piston types, though the rear one was liquid cooled. The IOL-200 (Injected, Opposed, Liquid-cooled, 200 cubic inch) engine from Voyager is in a display case at the Smithsonian; I have a picture of it.
I think Rutan's experience with the Predator, the Global Hawk and the aeroshell of the DC-X are far more indicative of his talents than Voyager; a very slow unpressurized aircraft is not much experience for a space-skimming vehicle which has to endure substantial heat loads on return to earth, but the others are much closer.
Commercial supersonic flight (at least at Mach 2) does not make economic sense. This was known many years ago; Concorde broke even on operating costs, but never paid for its development. Shutting down the aging, deteriorating fleet makes sense.
SpaceShipOne did more than break the sound barrier, it aimed toward altitudes and conditions unseen by private aviation. With those altitudes and conditions come possible markets, such as small-scale microgavity research on the cheap and even the mother of all roller-coaster rides. Here's hoping that it marks a realization that there are some things which don't work, and some things which do.
That's one option. Another (and possibly better) is just to put wires in conduit (run it 7 feet off the floor to avoid trip and head-banging hazards). You'll have to check your building codes to see if you can put a fat 3-wire cable inside conduit for the run through the air and down the wall to an outlet, or if you are required to run separate wires (better heat dissipation) and wire things directly into a junction box. That latter will certainly require intervention from building maintenance.
We do produce around two orders of magnitude more CO2 than volcanic activity each year. Damn. That is a sobering number.
Ain't it the truth. The real scandal is that millions of people "know" otherwise, due to false claims in media like talk radio.
The ash and aerosols from St. Helens and Pinatubo each caused a 2-3 year long 1-2C drop in global temperature.
This is a nit and I don't have time to research it, but I bet you'll find that while the effects might have been detectable for years, the time for which they were of that magnitude was much shorter.
You're proposing that, based on someone's unsubstantiated analysis, we expend Trillions of dollars to make changes that may be unnecessary.
It's not one analysis, it's a whole family of analyses, and even the ones postulating the smallest climactic changes project effects that would turn our world umop apisdn.
The USA has a $10 trillion economy, we are going to be spending trillions to add to, replace or repair infrastructure and durable goods (cars, appliances) anyway. The issue is that each dollar spent locks in the choices for many years into the future, so we need to spend those dollars wisely starting today. If additional money has to be spent (efficiency doesn't always cost more), it can often be recovered from savings down the line. We could recover far more if factors such as defense are considered (giving money to Arab oil producers leads to their promotion of radical Islam in madrassas, with results we can all recount by now). For one example of what we could do fairly easily, take a look at my other post here. I think that doing these things just as insurance is essential.
Where did I mention changing fuels? Did any of the improvements to date require exotic energy sources? No. We were burning coal, oil and natural gas (plus some hydropower) in 1950; with the exception of some hundreds of megawatts of wind, we're still burning coal, oil and natural gas today. We have a long way to go before we reach the limits of what's technically feasible to achieve, and there is one hell of a lot of low-hanging fruit that the advancing state of the art has left ripe and waiting to be picked with off-the-shelf technology.
That said, there are a lot of places where other sources of energy could fit in if we designed our systems flexibly enough to accomodate them. For instance, cheap concentrating solar could supply energy to hybrid cars on an as-available basis, cutting emissions of CO2 and all related pollutants in the bargain. You don't need to get fancy when simple will do; doubling efficiency and substituting for half of the remaining demand yields a 75% reduction, and those figures are definitely within reach with stuff we could make today. That's just one of many things that are feasible right now.
Why can't we buy this stuff off the shelf? Inertia and politics, I guess.
Dramatic decreases in emissions will most certainly have to be accomplished by decreased production. Retooling may now be an option, as Bush has relaxed some of the constraints on emission standards, the permit producers to make their plants more effecient, but may result in increased capacity for emissions. However, "environmentalists" and the media lambast Bush for this not because they care about the environment, but because they have an anti-capitalist agenda.
You're looking at (the text of) an environmentalist, who is also a capitalist who thinks that the political left is 80% loons. In short, you're wrong.
First, Kyoto did not require dramatic decreases in anything. A small reduction like 10% could be easily accomplished just by moving all new motor vehicles to hybrid technology, no other changes required. If you added some common-sense measures such as best-practice insulation standards in all building codes, you could take an even bigger whack out of emissions related to space heating and cooling (50% is fairly easy).
Second, some large improvements are easily accessible. If you combined an acid-rain abatement program with efficiency improvements and mandated that all old coal-fired powerplants be either retired or repowered with integrated-gasification combined-cycle plants, you'd boost efficiency from 30-33% to around 40%. This would give you a reduction in CO2 emissions between 20 and 25% per unit of electricity. It's been done; check this.
My beef with Bush is that he's obviously a pawn of the industrial interests. We created a regulatory regime for reducing pollution, but existing plants were grandfathered in and not required to do anything until they were replaced or upgraded. Industry's response was to game the system, failing to build new plants and claiming that their changes to old ones never met the requirements for having to clean them up. If you want to look at negative effects on the economy, think of all the employment that would have been generated in construction if those mandates had instead been on a timetable with no exceptions and those plants had been scrubbed, replaced or re-powered.
Bush's slimy acquiescence to the polluters is particularly galling to me, as I live in a state where the game fish are so loaded with mercury (mostly from coal-fired powerplants) that eating them steadily can cause acute mercury poisoning even in an adult. I don't even want to think what is happening to children (who are far more sensitive to heavy-metal poisoning), and when I see Bush touting his efforts on their behalf all I can think is "what a fucking liar".
We know (we've seen) that large volcanic eruptions can cause the global temperature to drop several degrees.
True, but this is due to ash and sulfate particulates which screen out sunlight. These fall out of the atmosphere over a period of months.
We also know a single volcano can spew out more CO2 during an eruption than all of industry for the past 200 years.
This statement is not just false, it is a damned lie. The CO2 content of the atmosphere has been measured on a frequent basis for decades. It shows almost no correlation with volcanic activity, but has a seasonal swing on top of an exponential upward curve which is all but certainly from human activity.
Historic volcanic eruptions can't even compete with human emissions of sulfur dioxide. That's how important we are. (If you don't believe me, look at DOE and EPA figures for sulfur emissions vs. recent volcanic eruptions like Pinatubo or El Chicon. If you actually think rather than hold blindly to an ideology, you will find it sobering.)
My point is: Although we have some data, it's inconclusive.
And you use this as a reason to continue a vast, uncontrolled experiment with possibly dire consequences. Why?
An analogy is to claim that you ought to glue yourself into a winter coat because it was cold last month. If it turns out to be hot tomorrow (solar activity continues to increase), the coat (extra greenhouse gases) could kill you from heatstroke. This is the kind of risk we're taking.
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I can think of one thing that might justify such effort, and that is a solar sail which would help pull the crew return vehicles to Mars and then return to Earth for the next. This could reduce the fuel requirements for launching a CRV to that sufficient get to an orbit a few thousand miles up, rather than Earth escape velocity; the improvement in mass delivered to Mars might be sufficient to make it worthwhile for second-generation missions.
You don't want to leave anything parked in orbit "just because". See this post.
5 km/sec is about 11,200 MPH. That's not even enough to make a good ICBM on Earth, but it'll get you completely off Mars. It is pretty obvious that we have had the rocket technology to get back from Mars for a long time, and getting back is much easier than getting there in the first place.
One of the things people keep claiming is that it's necessary to leave a return vehicle in Mars orbit. This is exactly how NASA got the $400 billion figure for a Mars mission; it is a huge mistake. Landing everything instead of leaving it in orbit has terrific advantages:
- You can aerobrake your entire mission instead of having to insert into orbit with rockets. This eliminates the mass budget for the fuel.
- You can manufacture your fuel supply for the return voyage from Martian atmosphere, instead of having to carry it with you. This buys you something like a 12:1 advantage.
- You avoid having to rendezvous with an orbiting return vehicle to get home; if you cannot rendezvous, you're dead.
- You avoid leaving your return ticket in orbit where you can't maintain or protect it, with its precious fuel in tanks which can be punctured by meteoroids, etc.
Not even NASA wanted to leave an orbiter for it's own sake after seeing Mars Direct. Zubrin has that much right.You can get a PDF of some of his later results here.
Again, nothing personal; this is part of attention-management. What I read is my business. How you react to what I decide to read is your problem, not mine. If you choose to waste your time writing flames I'll probably not see except as a response below my current threshold, it's your life (or lack thereof).
The forests in question are in Indonesia, where peat bogs full of old trees are first cut for lumber and then partially drained and planted as plantations. Drying out the peat makes it very susceptible to fire, which releases huge amounts of trapped carbon.
I'd ask you if this isn't faulty logic, but you've already admitted that logic and reason is not the purpose of the "Uma Thurman" posts. ;)
Just goes to show that Kyoto isn't the solution, because it ignores emissions by "developing countries" regardless of origin.
Besides, I bet you cringed when it was a liberal administration which tried to fire someone for using the word "niggardly", while the poster's experience sounds more like an embar-ass-ment of the right because a leftist isn't going to get bent out of shape for a three-letter-word.
Last, the pathetic state of knowlege of those who obtain teaching certificates is widely known, irrefutable and of no particular help to either side of the political spectrum.
The person who let that piece be printed in that form deserves to be the laughingstock of the science-editor community from now until he leaves the business. There is no excuse for getting high-school-level science facts wrong.
I hope that bar-coding can be used as an alternative to RFID for the small farmer, so that e.g. grass-fed operations can stay in business without having their costs driven up by the less-safe factory farms.
- steadfastness: they have been working on UnixWare since before SCO became a legal bully, and since they have nothing to do with the top management or legal shenanigans they feel that they are doing the right thing by continuing to support SCO's software vendors and customers.
This is not to say that looking for a new job isn't a good idea, but someone who finds themselves writing UnixWare code for the Canopy Group through no fault of their own is not morally obligated to jump ship until they have another ship to jump to.I have not heard of a commercial (or government, for that matter) effort to fill any one of those niches, let alone all of them.
Nice attempt to back-pedal and change the subject after being proved wrong, but given that you now say the corrections are irrelevant you beg the question of why you made such blatantly wrong assertions in the first place.I think Rutan's experience with the Predator, the Global Hawk and the aeroshell of the DC-X are far more indicative of his talents than Voyager; a very slow unpressurized aircraft is not much experience for a space-skimming vehicle which has to endure substantial heat loads on return to earth, but the others are much closer.
SpaceShipOne did more than break the sound barrier, it aimed toward altitudes and conditions unseen by private aviation. With those altitudes and conditions come possible markets, such as small-scale microgavity research on the cheap and even the mother of all roller-coaster rides. Here's hoping that it marks a realization that there are some things which don't work, and some things which do.
That's one option. Another (and possibly better) is just to put wires in conduit (run it 7 feet off the floor to avoid trip and head-banging hazards). You'll have to check your building codes to see if you can put a fat 3-wire cable inside conduit for the run through the air and down the wall to an outlet, or if you are required to run separate wires (better heat dissipation) and wire things directly into a junction box. That latter will certainly require intervention from building maintenance.
The USA has a $10 trillion economy, we are going to be spending trillions to add to, replace or repair infrastructure and durable goods (cars, appliances) anyway. The issue is that each dollar spent locks in the choices for many years into the future, so we need to spend those dollars wisely starting today. If additional money has to be spent (efficiency doesn't always cost more), it can often be recovered from savings down the line. We could recover far more if factors such as defense are considered (giving money to Arab oil producers leads to their promotion of radical Islam in madrassas, with results we can all recount by now). For one example of what we could do fairly easily, take a look at my other post here. I think that doing these things just as insurance is essential.
That said, there are a lot of places where other sources of energy could fit in if we designed our systems flexibly enough to accomodate them. For instance, cheap concentrating solar could supply energy to hybrid cars on an as-available basis, cutting emissions of CO2 and all related pollutants in the bargain. You don't need to get fancy when simple will do; doubling efficiency and substituting for half of the remaining demand yields a 75% reduction, and those figures are definitely within reach with stuff we could make today. That's just one of many things that are feasible right now.
Why can't we buy this stuff off the shelf? Inertia and politics, I guess.
First, Kyoto did not require dramatic decreases in anything. A small reduction like 10% could be easily accomplished just by moving all new motor vehicles to hybrid technology, no other changes required. If you added some common-sense measures such as best-practice insulation standards in all building codes, you could take an even bigger whack out of emissions related to space heating and cooling (50% is fairly easy).
Second, some large improvements are easily accessible. If you combined an acid-rain abatement program with efficiency improvements and mandated that all old coal-fired powerplants be either retired or repowered with integrated-gasification combined-cycle plants, you'd boost efficiency from 30-33% to around 40%. This would give you a reduction in CO2 emissions between 20 and 25% per unit of electricity. It's been done; check this.
My beef with Bush is that he's obviously a pawn of the industrial interests. We created a regulatory regime for reducing pollution, but existing plants were grandfathered in and not required to do anything until they were replaced or upgraded. Industry's response was to game the system, failing to build new plants and claiming that their changes to old ones never met the requirements for having to clean them up. If you want to look at negative effects on the economy, think of all the employment that would have been generated in construction if those mandates had instead been on a timetable with no exceptions and those plants had been scrubbed, replaced or re-powered.
Bush's slimy acquiescence to the polluters is particularly galling to me, as I live in a state where the game fish are so loaded with mercury (mostly from coal-fired powerplants) that eating them steadily can cause acute mercury poisoning even in an adult. I don't even want to think what is happening to children (who are far more sensitive to heavy-metal poisoning), and when I see Bush touting his efforts on their behalf all I can think is "what a fucking liar".
Historic volcanic eruptions can't even compete with human emissions of sulfur dioxide. That's how important we are. (If you don't believe me, look at DOE and EPA figures for sulfur emissions vs. recent volcanic eruptions like Pinatubo or El Chicon. If you actually think rather than hold blindly to an ideology, you will find it sobering.)
And you use this as a reason to continue a vast, uncontrolled experiment with possibly dire consequences. Why?An analogy is to claim that you ought to glue yourself into a winter coat because it was cold last month. If it turns out to be hot tomorrow (solar activity continues to increase), the coat (extra greenhouse gases) could kill you from heatstroke. This is the kind of risk we're taking.