Real survey of scientists about Global Warming

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smokeyjoe

Senior member
Dec 13, 1999
265
1
81
Originally posted by: miniMUNCH
PhD chemical engineer here... several of my PhD friends did climate/polution modeling for their PhD (one of the top groups in the world).

Sorry... the conclusions being drawn from the data and models are bullshit. Even most of my climate modeling friends would never go so far as make any of claims being put forth by the IPCC.

Look OP and others on here... many of you don't understand the math, the modeling, how the data is acquired, processed, massaged and then statistically mapped and compared to the models. They are making way more claims than the radical uncertainty of their data and models merit. Bottom line.

Many renown climate experts have said the same... some even who authored the original IPCC report.

So scientists like Dr. Kiminori Itoh, William Happer and AAAS member David Bromwich are not alone?

A few more and we might have a "consensus".
 

Craig234

Lifer
May 1, 2006
38,548
350
126
Originally posted by: BigDH01
No one will be dented here because GW has become politicized. Once this subject stepped into the realm of politics, any possibility of scientific debate, consensus, and action disappeared. This applies to everyone in my opinion.

Politics serve a huge disservice to mankind.

Uh, for all its problems, politics is still the only way the public generaly expesses its desired policies. Without politics, not much would get done in public policy.

It'd just be a fast return to the primitive societal model where the few powerful enslave the rest of the population. Deal with the issue of GW.
 

Jaskalas

Lifer
Jun 23, 2004
36,070
10,408
136
Originally posted by: BigDH01
No one will be dented here because GW has become politicized. Once this subject stepped into the realm of politics, any possibility of scientific debate, consensus, and action disappeared. This applies to everyone in my opinion.

Politics serve a huge disservice to mankind.

Your aim is wrong. Our two party system is the problem with our politics. It's right and wrong, good and evil, there are dangerous extremes and absolutes born from it.

In this case, hot and cold.
 

chess9

Elite member
Apr 15, 2000
7,748
0
0
Originally posted by: NeoV
Holy ownage? Can you even read something and comprehend it?

"Interesting that for question 1, 100% didn't say yes"

97% of the scientists WHO STUDY CLIMATOLOGY answered yes.

Other scientists polled - like meteorologists and petroleum scientists, had far lower percentages - 64 and 47 % respectively - Hence the comment -"The more you know about the field of climate science, the more likely you're to believe in global warming and humankind's contribution to it". The fact pointed out in the survey is that 97% of climatologists - the scientists that know these facts/studies/theories inside and out, agree that humans are influencing the warming trend we are experiencing.

Thanks Sagalore, what was I thinking - you of course know more about how to conduct a survey of scientists than the people involved here - they should have just contacted you.

Some of you are so blinded that you can't even comprehend what you are reading - mods included - Fern - I was pointing out that Corn-based ethanol was an example of a 'painful step', but I do believe that the work done in that field of research will lead to more promising uses, such as switchgrass, but if we don't start now, we'll never get there.

Brilliant reposte! Oh, and great OP.

CO2 is important because humans need oxygen in their air. If the air has high levels of carbon dioxide, and other gases noxious to humans, then human life is impacted. As I mentioned in another post, rates of COPD are now very high and asthma rates are rising alarmingly. Asthma rates may not be related to pollution issues, as the connection is hardly settled, but as someone who has very bad asthma, I can tell you that air pollution greatly exacerbates my asthma symptoms and almost everyone I know who has asthma avoids polluted air.

-Robert
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
I think you might also want to consider other reason behind the correlation between climate knowledge and belief in global warming. Usually, when I see something like this I would try to think of other logical reason why this coloration exists. And there is a VERY obvious one here which is the most basic one of all, MONEY. Climate scientists stand to make alot of money by having global warming be a big issue, that means people will fund more glimate research, and people in that field will get more grants and money etc. Maybe that seems silly to those who believe in global warming without question, but think of it this way, the people who know the most about fossil fuels believe its not bad for us. And the environmentalists all say that the only reason they believe that is because they stand to make money be believing it, well the same motivation exists for people working to prove global warming as it does to disprove it.

I'm sure many people have heard the quote:

"It"s very hard to convince a man of something if his job depends on him not believing it."

This applies to BOTH sides in any argument. And I have a heard time believing people who have such CLEAR monetary reasons for holding one view over another.
 

fskimospy

Elite Member
Mar 10, 2006
88,153
55,699
136
Originally posted by: BrownTown
I think you might also want to consider other reason behind the correlation between climate knowledge and belief in global warming. Usually, when I see something like this I would try to think of other logical reason why this coloration exists. And there is a VERY obvious one here which is the most basic one of all, MONEY. Climate scientists stand to make alot of money by having global warming be a big issue, that means people will fund more glimate research, and people in that field will get more grants and money etc. Maybe that seems silly to those who believe in global warming without question, but think of it this way, the people who know the most about fossil fuels believe its not bad for us. And the environmentalists all say that the only reason they believe that is because they stand to make money be believing it, well the same motivation exists for people working to prove global warming as it does to disprove it.

I'm sure many people have heard the quote:

"It"s very hard to convince a man of something if his job depends on him not believing it."

This applies to BOTH sides in any argument. And I have a heard time believing people who have such CLEAR monetary reasons for holding one view over another.

You have your incentives all mixed up.

Climatologists are not some sort of cartel that work together to give each other jobs. Science is a dog-eat-dog world. You do realize that the first scientist to disprove global warming will personally make a mint, probably get a Nobel prize, and will be famous for the rest of his life, right?

The incentives for scientists are to DISPROVE what the majority currently thinks, that's where the money is.
 

smokeyjoe

Senior member
Dec 13, 1999
265
1
81
Originally posted by: eskimospyScience is a dog-eat-dog world.


In a world of ruthless competition, is there no incentive to go along with a popular theory in order to keep your job and funding and not risk losing it by dissenting?


 

fskimospy

Elite Member
Mar 10, 2006
88,153
55,699
136
Originally posted by: smokeyjoe

In a world of ruthless competition, is there no incentive to go along with a popular theory in order to keep your job and funding and not risk losing it by dissenting?

What are all the richest, most famous, and most respected scientists all known for? Flipping the ruling paradigm on its head. I'm sure there are some people who just want to keep their heads down and get paid, but there are people like that in every walk of life. There are massive incentives for scientists to disprove the current system. Hell, look at all the notoriety individual scientists get for coming out against MMGW. Do you see that level of recognition for people who publish papers in support of it? Of course not. Now imagine how famous and rich one of those dissenters would be if they were actually correct.
 

Atheus

Diamond Member
Jun 7, 2005
7,313
2
0
Originally posted by: eskimospy
Originally posted by: BrownTown
I think you might also want to consider other reason behind the correlation between climate knowledge and belief in global warming. Usually, when I see something like this I would try to think of other logical reason why this coloration exists. And there is a VERY obvious one here which is the most basic one of all, MONEY. Climate scientists stand to make alot of money by having global warming be a big issue, that means people will fund more glimate research, and people in that field will get more grants and money etc. Maybe that seems silly to those who believe in global warming without question, but think of it this way, the people who know the most about fossil fuels believe its not bad for us. And the environmentalists all say that the only reason they believe that is because they stand to make money be believing it, well the same motivation exists for people working to prove global warming as it does to disprove it.

I'm sure many people have heard the quote:

"It"s very hard to convince a man of something if his job depends on him not believing it."

This applies to BOTH sides in any argument. And I have a heard time believing people who have such CLEAR monetary reasons for holding one view over another.

You have your incentives all mixed up.

Climatologists are not some sort of cartel that work together to give each other jobs. Science is a dog-eat-dog world. You do realize that the first scientist to disprove global warming will personally make a mint, probably get a Nobel prize, and will be famous for the rest of his life, right?

The incentives for scientists are to DISPROVE what the majority currently thinks, that's where the money is.

Not to mention kickbacks from the oil companies. How much money do hippies have floating around to bribe scientists? Not a lot I'd wager. I'd also wager that 90% of research scientists are almost unbribable - if they wanted money they'd be developing technology for some huge corporation.
 
Sep 12, 2004
16,852
59
86
Originally posted by: Atheus
Originally posted by: eskimospy
Originally posted by: BrownTown
I think you might also want to consider other reason behind the correlation between climate knowledge and belief in global warming. Usually, when I see something like this I would try to think of other logical reason why this coloration exists. And there is a VERY obvious one here which is the most basic one of all, MONEY. Climate scientists stand to make alot of money by having global warming be a big issue, that means people will fund more glimate research, and people in that field will get more grants and money etc. Maybe that seems silly to those who believe in global warming without question, but think of it this way, the people who know the most about fossil fuels believe its not bad for us. And the environmentalists all say that the only reason they believe that is because they stand to make money be believing it, well the same motivation exists for people working to prove global warming as it does to disprove it.

I'm sure many people have heard the quote:

"It"s very hard to convince a man of something if his job depends on him not believing it."

This applies to BOTH sides in any argument. And I have a heard time believing people who have such CLEAR monetary reasons for holding one view over another.

You have your incentives all mixed up.

Climatologists are not some sort of cartel that work together to give each other jobs. Science is a dog-eat-dog world. You do realize that the first scientist to disprove global warming will personally make a mint, probably get a Nobel prize, and will be famous for the rest of his life, right?

The incentives for scientists are to DISPROVE what the majority currently thinks, that's where the money is.

Not to mention kickbacks from the oil companies. How much money do hippies have floating around to bribe scientists? Not a lot I'd wager. I'd also wager that 90% of research scientists are almost unbribable - if they wanted money they'd be developing technology for some huge corporation.
Do you realize how many large companies are working R&D on technologies like CO2 sequestration, carbon scrubbers, alternatie energy, etc.? Imagining it's only hippies and greens on the side of MMGW is patently ridiculous. MMGW has become such an accepted belief before it has any proof there is tons of money being thrown its way by governments and SIGs. Go ask a climatologist how much funding is out there for studies that disprove MMGW. In fact, quite a few of the climatologists that don't buy into MMGW mention that very issue. If you don't ride the MMGW train, you very likely don't get funded.
 

charrison

Lifer
Oct 13, 1999
17,033
1
81
Originally posted by: chess9
Originally posted by: NeoV
Holy ownage? Can you even read something and comprehend it?

"Interesting that for question 1, 100% didn't say yes"

97% of the scientists WHO STUDY CLIMATOLOGY answered yes.

Other scientists polled - like meteorologists and petroleum scientists, had far lower percentages - 64 and 47 % respectively - Hence the comment -"The more you know about the field of climate science, the more likely you're to believe in global warming and humankind's contribution to it". The fact pointed out in the survey is that 97% of climatologists - the scientists that know these facts/studies/theories inside and out, agree that humans are influencing the warming trend we are experiencing.

Thanks Sagalore, what was I thinking - you of course know more about how to conduct a survey of scientists than the people involved here - they should have just contacted you.

Some of you are so blinded that you can't even comprehend what you are reading - mods included - Fern - I was pointing out that Corn-based ethanol was an example of a 'painful step', but I do believe that the work done in that field of research will lead to more promising uses, such as switchgrass, but if we don't start now, we'll never get there.

Brilliant reposte! Oh, and great OP.

CO2 is important because humans need oxygen in their air. If the air has high levels of carbon dioxide, and other gases noxious to humans, then human life is impacted. As I mentioned in another post, rates of COPD are now very high and asthma rates are rising alarmingly. Asthma rates may not be related to pollution issues, as the connection is hardly settled, but as someone who has very bad asthma, I can tell you that air pollution greatly exacerbates my asthma symptoms and almost everyone I know who has asthma avoids polluted air.

-Robert

asthma rates are trending, polluting is down significantly. There seems to be little correlation between the two.
 

smokeyjoe

Senior member
Dec 13, 1999
265
1
81
Originally posted by: BrownTown
yay for clean coal extending our lives?


Clean coal technology is comical.. they want to bury the CO2 underground or gasify coal to reduce the harmful pollutants.. both are unproven and the latter has been shown to be very expensive so far. I really don't understand why no one talks more about georthermal energy since we have a few plants in the US already and there are numerous countries already using it. Pros, Cons?
 

BigDH01

Golden Member
Jul 8, 2005
1,631
88
91
Originally posted by: Craig234
Originally posted by: BigDH01
No one will be dented here because GW has become politicized. Once this subject stepped into the realm of politics, any possibility of scientific debate, consensus, and action disappeared. This applies to everyone in my opinion.

Politics serve a huge disservice to mankind.

Uh, for all its problems, politics is still the only way the public generaly expesses its desired policies. Without politics, not much would get done in public policy.

It'd just be a fast return to the primitive societal model where the few powerful enslave the rest of the population. Deal with the issue of GW.

I should have said modern identity politics. The term "politics" simply refers to the interactions that occur within any social group.

Modern politics have stripped people of any sense of reason and instead replaces that void with a sense of identity. This process is quite obvious even on these boards. Many posters here think of a tree hugging hippie from San Francisco when they hear the word liberal and confederate-flag-waving redneck from Alabama when they think of conservative. Amazingly enough, those individuals that fit the above stereotypes are likely proud of their political identity and ideology.

The point is, modern politics have not only separated us based on what we believe, it has separated us based on who we are. There are definitely some truths in the aforementioned stereotypes. And the political leaders play on this when they try to appear to be a part of such groups and degrade other groups of people. Look at the Republican rally videos. Sure, you heard cries of "Socialist," etc, but you also heard, "go back to Europe." It's as if people believe that by simply being European, you are the liberal enemy.

As long as people have internalized their party (and their party's beliefs) as being part of their identity, there will be no logical discourse. It is impossible to take an unbiased view of a scientific matter if that matter has become part of your party's platform and therefore part of your own identity. To criticize that theory or belief is to not only criticize the science, or lack thereof, but the people who've adopted that belief as part of their political identity.

In the case of GW, there is plenty of blame to go around. Over-eager scientists attempting to get funding pushed this issue into our political realms. The cause is taken to extreme by Al Gore (who is despised by Republicans) and Rush Limbaugh (similarly despised by Democrats). With this sort of activism, it didn't take long for the parties to adopt these views and for Republicans and Democrats to internalize them. As such, I find it very hard to believe that any consensus will be reached and any real conclusion made one way or the other about man-made global warming.
 

kylebisme

Diamond Member
Mar 25, 2000
9,396
0
0
Originally posted by: BigDH01
The point is, modern politics have not only separated us based on what we believe, it has separated us based on who we are.

On the contrary, people divide themselves from others based on what they choose to believe, rather than understanding the reality of what they are.
 

BigDH01

Golden Member
Jul 8, 2005
1,631
88
91
Originally posted by: TheSnowman
Originally posted by: BigDH01
The point is, modern politics have not only separated us based on what we believe, it has separated us based on who we are.

On the contrary, people divide themselves from others based on what they choose to believe, rather than understanding the reality of what they are.

And we can get into a long discussion about what people really are and what they perceive themselves to be, but I'm tired of explaining to a friend that makes 30k/yr that her taxes aren't going to be crippling under the Obama administration. Hannity has sold her the identity of an upper middle-class, government-oppressed, white worker who's money is going to be taken and given to poor people. I know specifically that it was Hannity as she as said as such.

This is a girl that's really burdened by her student loan debt and the increasing costs of education. Her parents had no money to help her as her father died when she was young. She's trying to go back to nursing school now but can't afford it. She could benefit greatly from social programs that subsidize education and reduce those costs. She's the working lower middle-class in every way but her perception. She hates Obama. Our identities and our realities are often two entirely different things.
 
Nov 30, 2006
15,456
389
121
Originally posted by: BigDH01
Originally posted by: Craig234
Originally posted by: BigDH01
No one will be dented here because GW has become politicized. Once this subject stepped into the realm of politics, any possibility of scientific debate, consensus, and action disappeared. This applies to everyone in my opinion.

Politics serve a huge disservice to mankind.

Uh, for all its problems, politics is still the only way the public generaly expesses its desired policies. Without politics, not much would get done in public policy.

It'd just be a fast return to the primitive societal model where the few powerful enslave the rest of the population. Deal with the issue of GW.

I should have said modern identity politics. The term "politics" simply refers to the interactions that occur within any social group.

Modern politics have stripped people of any sense of reason and instead replaces that void with a sense of identity. This process is quite obvious even on these boards. Many posters here think of a tree hugging hippie from San Francisco when they hear the word liberal and confederate-flag-waving redneck from Alabama when they think of conservative. Amazingly enough, those individuals that fit the above stereotypes are likely proud of their political identity and ideology.

The point is, modern politics have not only separated us based on what we believe, it has separated us based on who we are. There are definitely some truths in the aforementioned stereotypes. And the political leaders play on this when they try to appear to be a part of such groups and degrade other groups of people. Look at the Republican rally videos. Sure, you heard cries of "Socialist," etc, but you also heard, "go back to Europe." It's as if people believe that by simply being European, you are the liberal enemy.

As long as people have internalized their party (and their party's beliefs) as being part of their identity, there will be no logical discourse. It is impossible to take an unbiased view of a scientific matter if that matter has become part of your party's platform and therefore part of your own identity. To criticize that theory or belief is to not only criticize the science, or lack thereof, but the people who've adopted that belief as part of their political identity.

In the case of GW, there is plenty of blame to go around. Over-eager scientists attempting to get funding pushed this issue into our political realms. The cause is taken to extreme by Al Gore (who is despised by Republicans) and Rush Limbaugh (similarly despised by Democrats). With this sort of activism, it didn't take long for the parties to adopt these views and for Republicans and Democrats to internalize them. As such, I find it very hard to believe that any consensus will be reached and any real conclusion made one way or the other about man-made global warming.
Your post is an excellent synopsis of the truth. It's like 90% of the population have become zombies with their identity and self worth totally based upon flimsy and abstract partisan ideologies. They must fill the void and this is how they do it. It's amazing on how blind we've become.
 

SagaLore

Elite Member
Dec 18, 2001
24,036
21
81
Originally posted by: Marlin1975
Antarctica Getting Warmer After All (From Fox)

"Antarctica is warming, and it's warming at the same rate as the rest of the planet,"

In stark contrast, a large part of the continent ? the East Antarctic Ice Sheet ? was found to be getting colder. The cooling was linked to another anthropogenic (human-caused) effect: ozone depletion.

...

"Efforts to repair the ozone layer eventually will begin taking effect and the hole could be eliminated by the middle of this century. If that happens, all of Antarctica could begin warming on a par with the rest of the world," Steig said.

Crap. We need to start depleting the ozone layer again! :shocked:
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
Originally posted by: smokeyjoe
Originally posted by: BrownTown
yay for clean coal extending our lives?


Clean coal technology is comical.. they want to bury the CO2 underground or gasify coal to reduce the harmful pollutants.. both are unproven and the latter has been shown to be very expensive so far. I really don't understand why no one talks more about georthermal energy since we have a few plants in the US already and there are numerous countries already using it. Pros, Cons?


- Coal gassification (though idiotic IMO) is not unproven, its been sued for over 50+ years, long than most "green" technologies (except windmills :p)

- The reason geothermal isn't used is because only in a very few places is the heat close enough to the surface to tap. IF you drill down far enough anywhere then you will reach heat, but then you lose it all trying to pump it up thousands of feet.
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
Originally posted by: BigDH01
And we can get into a long discussion about what people really are and what they perceive themselves to be, but I'm tired of explaining to a friend that makes 30k/yr that her taxes aren't going to be crippling under the Obama administration. Hannity has sold her the identity of an upper middle-class, government-oppressed, white worker who's money is going to be taken and given to poor people. I know specifically that it was Hannity as she as said as such.

This is a girl that's really burdened by her student loan debt and the increasing costs of education. Her parents had no money to help her as her father died when she was young. She's trying to go back to nursing school now but can't afford it. She could benefit greatly from social programs that subsidize education and reduce those costs. She's the working lower middle-class in every way but her perception. She hates Obama. Our identities and our realities are often two entirely different things.

she sounds exactly like the type of person who would become a Republican (working hard in life and only asking that the government get out of her way, not for handouts). kinda like the woman BrownTown wants to marry some day :p... is she hot?
 

smokeyjoe

Senior member
Dec 13, 1999
265
1
81
Originally posted by: BrownTown

- The reason geothermal isn't used is because only in a very few places is the heat close enough to the surface to tap. IF you drill down far enough anywhere then you will reach heat, but then you lose it all trying to pump it up thousands of feet.


I haven't seen that stated anywhere. Just wondering where you heard that? I have been perusing this 2006 MIT report on the subject - http://geothermal.inel.gov/pub..._geothermal_energy.pdf

Found it through wiki (http://en.wikipedia.org/wiki/E...ced_Geothermal_System) where it stated these major findings -

Major Findings

1) Resource Size: The MIT report calculated the United States total EGS resources from 3-10 km to be over 13,000 zettajoules, of which over 200 ZJ would be extractable, with the potential to increase this to over 2,000 ZJ with technology improvements - sufficient to provide all the world's current energy needs for several millennia[3]. The report found that total geothermal resources, including hydrothermal and geo-pressured resources, to equal 14,000 ZJ - or roughly 140,000 times total U.S. annual primary energy use.

2) Development Potential: With a modest R&D investment of $1 billion over 15 years (or the cost of one coal power plant), the report estimated that 100 GWe (gigawatts of electricity) or more could be installed by 2050 in the United States. The report further found that the "recoverable" resource (that accessible with today's technology) to be between 1.2-12.2 million MW for the conservative and moderate recovery scenarios respectively.

3) Cost: The report found EGS could be capable of producing electricity for free. EGS costs were found to be sensitive to four main factors: (All of which could be government subsidized) 1) Temperature of the resource 2) Fluid flow through the system measured in liters/second 3) Drilling Costs 4) Power conversion efficiency. This technology has the potential to power the world at little or no cost to the population.

In addition the report has a wealth of data on EGS technology, trial wells and EGS economics.

Seems rather promising to me and extremely cost effective.

edit: oh look, the Department of Energy is funding a geothermal project - http://e-center.doe.gov/doebiz.nsf/UNID/CDD241865BE570348525752300577395?OpenDocument

Let's hope they use it for more than providing energy for government buildings.
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
Originally posted by: smokeyjoe
Originally posted by: BrownTown

- The reason geothermal isn't used is because only in a very few places is the heat close enough to the surface to tap. IF you drill down far enough anywhere then you will reach heat, but then you lose it all trying to pump it up thousands of feet.


I haven't seen that stated anywhere. Just wondering where you heard that? I have been perusing this 2006 MIT report on the subject - http://geothermal.inel.gov/pub..._geothermal_energy.pdf

Found it through wiki (http://en.wikipedia.org/wiki/E...ced_Geothermal_System) where it stated these major findings -

Major Findings

1) Resource Size: The MIT report calculated the United States total EGS resources from 3-10 km to be over 13,000 zettajoules, of which over 200 ZJ would be extractable, with the potential to increase this to over 2,000 ZJ with technology improvements - sufficient to provide all the world's current energy needs for several millennia[3]. The report found that total geothermal resources, including hydrothermal and geo-pressured resources, to equal 14,000 ZJ - or roughly 140,000 times total U.S. annual primary energy use.

2) Development Potential: With a modest R&D investment of $1 billion over 15 years (or the cost of one coal power plant), the report estimated that 100 GWe (gigawatts of electricity) or more could be installed by 2050 in the United States. The report further found that the "recoverable" resource (that accessible with today's technology) to be between 1.2-12.2 million MW for the conservative and moderate recovery scenarios respectively.

3) Cost: The report found EGS could be capable of producing electricity for free. EGS costs were found to be sensitive to four main factors: (All of which could be government subsidized) 1) Temperature of the resource 2) Fluid flow through the system measured in liters/second 3) Drilling Costs 4) Power conversion efficiency. This technology has the potential to power the world at little or no cost to the population.

In addition the report has a wealth of data on EGS technology, trial wells and EGS economics.

Seems rather promising to me and extremely cost effective.

edit: oh look, the Department of Energy is funding a geothermal project - http://e-center.doe.gov/doebiz.nsf/UNID/CDD241865BE570348525752300577395?OpenDocument

Let's hope they use it for more than providing energy for government buildings.


Pretty simple really, it takes energy to push water (or other working fluid) through thousands of feet of piping, at a point the amount of energy to pump the working fluid is more then the energy being brought up. Also of note is the fact that the heat will be relatively very low, so the temperature difference between the heat source (underground) and heat sink (cooling tower) meaning very poor efficiency. Also, as soon as you get away from teh heat source you are still pumping the water up a considerable distance through COLD rock, so again you are losing energy. ITs not necessarily a physical limit as to how far you can go down until you reach hot enough rock, but the farther you go the cost will increase exponentially (since you are using more and more energy to get less and less efficiency).