Official Global Warming thread (merged)

[PKT_VOL]

We’ve been through the weather =/= climate discussion (even sandvol has conceded this), but I’ll rehash it. The essential difference between them is weather is chaotic while climate is weather averaged over time.

“A change in temperature of 7º Celsius from one day to the next is barely worth noting when you are discussing weather. Seven degrees, however, make a dramatic difference when talking about climate. When the Earth's AVERAGE temperature was 7ºC cooler than the present, ice sheets a mile thick were on top of Manhattan! A good analogy of the difference between weather and climate is to consider a swimming pool. Imagine that the pool is being slowly filled. If someone dives in there will be waves. The waves are weather, and the average water level is the climate. A diver jumping into the pool the next day will create more waves, but the water level (aka the climate) will be higher as more water flows into the pool. In the atmosphere the water hose is increasing greenhouse gases. They will cause the climate to warm but we will still have changing weather (waves). Climate scientists use models to forecast the average water level in the pool, not the waves.”

The difference between weather and climate

I am well aware of the difference between between "weather" and "climate". However, I think my point was lost on you.

My problem is not with the difference in the semantics or concepts of between "weather" and "climate", but rather with the ignorance of the physical dynamics/natural laws which underscores and determines both. There is no doubt that there are many, many different factors (physical dynamics) that go into the overall very complex natural laws of climate. With all the weather stations, radars, known topography, data, known past weather system, computer models, etc., we still look at the underlying physical dynamics/natural laws as a labyrinth yet to be solved or truly understood.

To use your analogy of the pool, feeling up the water and having the waves represent "weather" and the water level represent "climate", my point would be that we do not yet understand the fluid dynamics of the water that is filling up the pool. If we understood the fluid dynamics of the pool, we would be able to understand and predict BOTH the waves (weather) and water level (climate) with accuracy. Thus, I do not fundamentally view "weather" as "chaotic". Sure, it may seem (key word) chaotic, but it is following the same forces and dynamics that climate follows (since they are one in the same; different sides of the same coin if you will). I think such a notion, distinction without a difference, is a misnomer.

Do we know that carbon dioxide is a greenhouse gas based on our understanding of chemistry in the laboratory? Sure. Should we expect temperatures to rise with the pumping of carbon dioxide into the atmosphere assuming (key word) that all other factors/physical dynamics stay the same? Absolutely. Where I differ from ardent the global warming camp is in the assumption that all other factors (know or unknown) will stay constant. Additionally, since we do not know all those factors or how they truly interact, either spontaneously or over time, I find predictions and computer climate change models pretty worthless.

 

[PKT_VOL]

The earth is nowhere even close to running out of fossil fuels and it may never run out. It will likely be many decades before a suitable alternative to crude oil is developed. As long as there are machines with moving parts, gears etc that need lubrication, oil will always remain.

I did not state that we would never use fossil fuels. I merely stated:

the desire to relinquish fossil fuels has always been there. It is just a matter time until technological innovation makes ditching fossil fuels worthwhile on a significant scale.

The desire has been there for a number of different reasons; environmental, political, geopolitical, national security, etc. There will always be secondary needs for petroleum (grease as you mentioned) but those secondary needs are not the driving force for oil/fossil fuels. Furthermore, nobody knows when we are going to run out. The more we understand geology, the better tools/technology we have for geology, the better tools/technology we have for extraction, etc. the more oil becomes available. Having said that, there is no doubt it is a finite resource. As far a alternative technology is concerned, the basics are there. It is just a matter of improving the technology and making it cost effective. That will happen one way or another (either on it's own via technological innovation or the price of oil will make it cost effective).

As far as global warming goes, I have a question. If the whole earth reduced greenhouse gas emissions by say 90% by the end of this year, would it really make that much of a difference? Do people really think humans have a major effect on the weather?

I tend to think we overemphasize our impact. Then again, I think it comes from the same anthropocentric thinking that has plagued mankind since civilization began. One can look at Krakatoa, Yellowstone, Chicxulub asteroid, etc. and see that we are not nearly as important as we tend to think. That said, even though I don't think we are solely responsible (or necessarily the driving force of climate change of any type) I do think it is common sense that we are not helping the situation or ourselves by pumping out carbon dioxide.

 

[BartW]

I am well aware of the difference between between "weather" and "climate". However, I think my point was lost on you.

My problem is not with the difference in the semantics or concepts of between "weather" and "climate", but rather with the ignorance of the physical dynamics/natural laws which underscores and determines both. There is no doubt that there are many, many different factors (physical dynamics) that go into the overall very complex natural laws of climate. With all the weather stations, radars, known topography, data, known past weather system, computer models, etc., we still look at the underlying physical dynamics/natural laws as a labyrinth yet to be solved or truly understood.

To use your analogy of the pool, feeling up the water and having the waves represent "weather" and the water level represent "climate", my point would be that we do not yet understand the fluid dynamics of the water that is filling up the pool. If we understood the fluid dynamics of the pool, we would be able to understand and predict BOTH the waves (weather) and water level (climate) with accuracy. Thus, I do not fundamentally view "weather" as "chaotic". Sure, it may seem (key word) chaotic, but it is following the same forces and dynamics that climate follows (since they are one in the same; different sides of the same coin if you will). I think such a notion, distinction without a difference, is a misnomer.

Do we know that carbon dioxide is a greenhouse gas based on our understanding of chemistry in the laboratory? Sure. Should we expect temperatures to rise with the pumping of carbon dioxide into the atmosphere assuming (key word) that all other factors/physical dynamics stay the same? Absolutely. Where I differ from ardent the global warming camp is in the assumption that all other factors (know or unknown) will stay constant. Additionally, since we do not know all those factors or how they truly interact, either spontaneously or over time, I find predictions and computer climate change models pretty worthless.

You’re still missing the fundamental difference between weather and climate. Weather is chaotic because small differences in initial conditions can cause large differences in the evolution of that system (think chaos theory, butterfly effect). Fluid dynamics – the waves in the pool – are also chaotic. However climate – the average water level – is not chaotic. All you need to know is how much water is entering/leaving the pool. We know how much heat is entering and leaving the earth system. This is a measurable property.

Don’t you think climate scientists considered the possibility that the warming trend is part of a natural cycle? The fact is there is much more evidence besides the correlation between rising temperatures and increased greenhouse gases. We also see stratospheric/upper atmospheric cooling, increasing tropopause height, decreasing diurnal temperature range, increased downward longwave radiation, decreased upward longwave radiation, and much more. These are all predictions the AGW hypothesis made that turned out to be true, solidifying it as a theory. That’s how the scientific method works. There would be no reason for these phenomena if the warming is part of a natural cycle. Sure, it’s possible that we wake up tomorrow to a colder sun, but I wouldn’t count on it. We have to assume natural laws operate the same way in the past, present and future. Otherwise science would have no predictive power.

 

[PKT_VOL]

You’re still missing the fundamental difference between weather and climate. Weather is chaotic because small differences in initial conditions can cause large differences in the evolution of that system (think chaos theory, butterfly effect). Fluid dynamics – the waves in the pool – are also chaotic. However climate – the average water level – is not chaotic. All you need to know is how much water is entering/leaving the pool. We know how much heat is entering and leaving the earth system. This is a measurable property.

I totally disagree that there is a fundamental difference between "weather" and "climate". The only difference is the temporal state in which they are observed measured. They are bound by the same natural laws and physical factors.Thus, "weather" being truly chaotic is absurd to me.

Don’t you think climate scientists considered the possibility that the warming trend is part of a natural cycle? The fact is there is much more evidence besides the correlation between rising temperatures and increased greenhouse gases. We also see stratospheric/upper atmospheric cooling, increasing tropopause height, decreasing diurnal temperature range, increased downward longwave radiation, decreased upward longwave radiation, and much more. These are all predictions the AGW hypothesis made that turned out to be true, solidifying it as a theory. That’s how the scientific method works. There would be no reason for these phenomena if the warming is part of a natural cycle. Sure, it’s possible that we wake up tomorrow to a colder sun, but I wouldn’t count on it. We have to assume natural laws operate the same way in the past, present and future. Otherwise science would have no predictive power.

I don't see how the sentence before the bold supports the AGW exclusively over climate change by natural causes or climate change via a combination of natural causes and man-made causes.

 

[BartW]

I totally disagree that there is a fundamental difference between "weather" and "climate". The only difference is the temporal state in which they are observed measured. They are bound by the same natural laws and physical factors.Thus, "weather" being truly chaotic is absurd to me.

Take a look at the Chaos Theory wiki. I’m not using the word chaos in the descriptive sense: chaos is a very real mathematical/physical phenomenon. Notice under the applications Wikipedia lists meteorology and fluid dynamics among several fields but not climatology (now don't go edit the wiki ). Weather is difficult to pinpoint but climate is averaged over space and time. Forecasting weather is a completely different beast from modeling climate.

That said it’s worth noting that meteorology has improved significantly over the past decades. Everyone b!tches and moans about weather forecasters when it snows a few inches more or less than predicted but overall their forecasts have gotten pretty accurate. The underlying physical principles are well understood it’s just difficult to predict weather because immeasurably small changes in initial conditions can cause the system to evolve differently. Chaos Theory.

I don't see how the sentence before the bold supports the AGW exclusively over climate change by natural causes or climate change via a combination of natural causes and man-made causes.

If you can come up with a natural mechanism that explains these phenomena you will win a Nobel prize. It would be an awfully large coincidence if all lines of reasoning (and there are many) that led climate scientists to accept global warming were actually the side effects of some yet unknown natural phenomena.

 

[BigOrangeTrain]

I did not state that we would never use fossil fuels. I merely stated:



The desire has been there for a number of different reasons; environmental, political, geopolitical, national security, etc. There will always be secondary needs for petroleum (grease as you mentioned) but those secondary needs are not the driving force for oil/fossil fuels. Furthermore, nobody knows when we are going to run out. The more we understand geology, the better tools/technology we have for geology, the better tools/technology we have for extraction, etc. the more oil becomes available. Having said that, there is no doubt it is a finite resource. As far a alternative technology is concerned, the basics are there. It is just a matter of improving the technology and making it cost effective. That will happen one way or another (either on it's own via technological innovation or the price of oil will make it cost effective).



I tend to think we overemphasize our impact. Then again, I think it comes from the same anthropocentric thinking that has plagued mankind since civilization began. One can look at Krakatoa, Yellowstone, Chicxulub asteroid, etc. and see that we are not nearly as important as we tend to think. That said, even though I don't think we are solely responsible (or necessarily the driving force of climate change of any type) I do think it is common sense that we are not helping the situation or ourselves by pumping out carbon dioxide.

Sorry about the fossil fuel comment that was not meant to be derogatory against you. I agree that we are not helping by pumping out all that CO2. I just wonder exactly HOW MUCH we are hurting things. I mean volcanic eruptions eject massive amounts if CO2 into the atmosphere, even small eruptions. Honestly I really don't know. I just have this feeling that the climate is way too complex for us humans to effect it severely.

 

[BartW]

Sorry about the fossil fuel comment that was not meant to be derogatory against you. I agree that we are not helping by pumping out all that CO2. I just wonder exactly HOW MUCH we are hurting things. I mean volcanic eruptions eject massive amounts if CO2 into the atmosphere, even small eruptions. Honestly I really don't know. I just have this feeling that the climate is way too complex for us humans to effect it severely.

I think this is the common theme among most skeptics, and it's completely understandable. On the face of it the idea that we miniscule humans can significantly impact something as big as the Earth is incredible. But it is what the data shows.

Then again, it's not all that surprising when you consider that we emit several billion tons of CO2 into the atmosphere annually and have been doing so for decades. That's orders of magnitude greater the amount emitted by volcanoes (link). In fact major volcanic eruptions have a cooling effect due to the sulfides they shoot into the stratosphere.

 

[PKT_VOL]

Take a look at the Chaos Theory wiki. I’m not using the word chaos in the descriptive sense: chaos is a very real mathematical/physical phenomenon. Notice under the applications Wikipedia lists meteorology and fluid dynamics among several fields but not climatology (now don't go edit the wiki ). Weather is difficult to pinpoint but climate is averaged over space and time. Forecasting weather is a completely different beast from modeling climate.

That said it’s worth noting that meteorology has improved significantly over the past decades. Everyone b!tches and moans about weather forecasters when it snows a few inches more or less than predicted but overall their forecasts have gotten pretty accurate. The underlying physical principles are well understood it’s just difficult to predict weather because immeasurably small changes in initial conditions can cause the system to evolve differently. Chaos Theory.

Needless to say, I disagree with the bold. Then again, I am sure it is rooted in different meanings/definitions of "well understood".

I am fine with Chaos Theory. No doubt that seemingly subtle differences in starting points of a system can drastically alter the end results of the systems.

It doesn't change the equation for me. If one cannot understand how the various factors (in a system) work on their own, their starting points, how they work together, etc, it makes the overall system of prediction is pretty worthless.

To put another way, why would the computer models which predict the meteorology be subject to (and excused via) Chaos Theory but the models of predicting climate change wouldn't? "Averages" wouldn't make a damn bit of difference when the system is much larger (the Earth versus a particular area of Earth), over a much greater period of time, involving many more factors, etc. with respect to the same subtle changes needed for Chaos Theory to happen. Not to mention "averaging" in itself is intentionally altering/generalizing specific data points; seems to invite Chaos Theory rather than eliminating it. Applying Chaos Theory to meteorology models but not climate change models seems absurd to me.

Who knows, maybe we have drastically different understandings of Chaos Theory.

If you can come up with a natural mechanism that explains these phenomena you will win a Nobel prize. It would be an awfully large coincidence if all lines of reasoning (and there are many) that led climate scientists to accept global warming were actually the side effects of some yet unknown natural phenomena.

It is simple philosophy of science. Coincidence does not equal causation. Assuming one variable is the sole source of change in a system which other variables cannot be held constant (they are constantly in a state of flux), and in a system in which we are unsure if we know all possible variables of the system, whether they change in importance to the system over time or under different conditions, is painfully naive and jumping the gun.

Again, I will be the first to admit given our basic understanding of chemistry, pumping carbon dioxide, methane, etc. into the atmosphere is not a smart idea and will, at some point (if it hasn't already) if all other variables remain constant, result in high temperatures (otherwise known as "AGW").

I am just disturbed by the rush to an anthropocentric blameworthy judgement on climate and the foolhardy faith in climate models. Full truth be known, I am very suspicious of all anthropocentric sentiments; not just AGW.

 

[BartW]

Needless to say, I disagree with the bold. Then again, I am sure it is rooted in different meanings/definitions of "well understood".

I am fine with Chaos Theory. No doubt that seemingly subtle differences in starting points of a system can drastically alter the end results of the systems.

It doesn't change the equation for me. If one cannot understand how the various factors (in a system) work on their own, their starting points, how they work together, etc, it makes the overall system of prediction is pretty worthless.

To put another way, why would the computer models which predict the meteorology be subject to (and excused via) Chaos Theory but the models of predicting climate change wouldn't? "Averages" wouldn't make a damn bit of difference when the system is much larger (the Earth versus a particular area of Earth), over a much greater period of time, involving many more factors, etc. with respect to the same subtle changes needed for Chaos Theory to happen. Not to mention "averaging" in itself is intentionally altering/generalizing specific data points; seems to invite Chaos Theory rather than eliminating it. Applying Chaos Theory to meteorology models but not climate change models seems absurd to me.

Who knows, maybe we have drastically different understandings of Chaos Theory.

The inherent averaging nature of climate is what smoothens weather’s chaotic behavior. The previous analogy is pretty good. If someone jumps in the pool it’s difficult to predict the water level at some specific point (X,Y) in the pool at some specific time t in the future. But predicting the average water level is straightforward and doesn’t depend on the waves in the pool. I can try another analogy if you like. Heck you can just look at a graph of global average temperature vs. time and see that it is nothing like the plot of a chaotic system. We may have different understandings of Chaos Theory. I spent quite a bit of time studying it in my classical mechanics sequence in undergrad so hopefully I can explain it to you properly.

It is simple philosophy of science. Coincidence does not equal causation. Assuming one variable is the sole source of change in a system which other variables cannot be held constant (they are constantly in a state of flux), and in a system in which we are unsure if we know all possible variables of the system, whether they change in importance to the system over time or under different conditions, is painfully naive and jumping the gun.

Again, I will be the first to admit given our basic understanding of chemistry, pumping carbon dioxide, methane, etc. into the atmosphere is not a smart idea and will, at some point (if it hasn't already) if all other variables remain constant, result in high temperatures (otherwise known as "AGW").

I am just disturbed by the rush to an anthropocentric blameworthy judgement on climate and the foolhardy faith in climate models. Full truth be known, I am very suspicious of all anthropocentric sentiments; not just AGW.

So we should assume every independent line of evidence - including many predictions based on the AGW hypothesis that, upon further research, turned out to be correct – is a coincidence? That’s not how the scientific method works. Hypothesis -> prediction -> test -> observations -> support/reject hypothesis. Nowhere do we disregard the results.

To you PKT, and the skeptics in general, what evidence would convince you?

 

[zreeves]

To you PKT, and the skeptics in general, what evidence would convince you?

if the surface of the planet spontaneously combusted

 

[Sandvol]

Just trying to spark conversation but we can stay in flat earth society and continue debating the science. I'd be more interested in discussing the actual politics but this has been entertaining enough.

If historical records are accurate there was a "scientific consensus" the Earth was flat. It was that minority denier Columbus who proved them wrong.

Historically when there is a scientific consensus the consensus is usually wrong. Scientific theory or law usually emanates from one lone investigator dissenter like Newton or Einstein. AGW is nothing more than a liberal hoax. Most of the people on this board aren't scientists but there are a lot of professionals and smart people and they recognize BS.

 

[BartW]

If historical records are accurate there was a "scientific consensus" the Earth was flat. It was that minority denier Columbus who proved them wrong.

Historically when there is a scientific consensus the consensus is usually wrong. Scientific theory or law usually emanates from one lone investigator dissenter like Newton or Einstein. AGW is nothing more than a liberal hoax. Most of the people on this board aren't scientists but there are a lot of professionals and smart people and they recognize BS.

LMAO. Let me guess, Fred Singer is today’s Albert Einstein? So we should ignore every scientific consensus because it’s probably wrong? Revert to the Stone Age? I already posted this, but the fact that the earth is round was discovered millennia ago. Eratosthenes even measured the Earth’s circumference to an impressive degree of accuracy in the 3rd century BC. It was a scientific consensus long before Columbus. The general public is always slower to accept paradigm-shifting discoveries. I’m sure there were plenty of blacksmiths, farmers, bakers, and other professionals back in the day that thought, “It looks pretty darn flat to me!”

This is one of the sillier bones to pick.

 

[Hurd That]

Global warming is an obvious scam. Anyone who disagrees, I challenge to prove me wrong

 

[PKT_VOL]

The inherent averaging nature of climate is what smoothens weather’s chaotic behavior. The previous analogy is pretty good. If someone jumps in the pool it’s difficult to predict the water level at some specific point (X,Y) in the pool at some specific time t in the future. But predicting the average water level is straightforward and doesn’t depend on the waves in the pool. I can try another analogy if you like. Heck you can just look at a graph of global average temperature vs. time and see that it is nothing like the plot of a chaotic system. We may have different understandings of Chaos Theory. I spent quite a bit of time studying it in my classical mechanics sequence in undergrad so hopefully I can explain it to you properly.

Again, we are talking about the same system, same natural laws. Chaos Theory would apply uniformly.

As for the pool example, if one has all relevant information of the system, it would not be that hard providing the fluid dynamics (natural laws of the system in question) are correct and the information/data entered into the system/simulation is correct. However, as your analogy correctly points out, that is a big "if" and is why climate/meteorology models are unreliable.

So we should assume every independent line of evidence - including many predictions based on the AGW hypothesis that, upon further research, turned out to be correct – is a coincidence? That’s not how the scientific method works. Hypothesis -> prediction -> test -> observations -> support/reject hypothesis. Nowhere do we disregard the results.

1) If H (Hypothesis) is true, then P (Prediction) is also true
2) Test and Observations say P is true
__________________________________________

Conclusion: H is true.

This is invalid reasoning. It is known formally as "affirming the consequent". In other words, H is not logically only sufficient for P to be true. It could be that some other factors or hypothesis (X) account for why P is true.

We could easily turn this around with the ridiculous hypothesis that "God was angry and wanted humans to feel the discomfort of hell on Earth due to their sin, hence he wanted to warm the Earth." Such a hypothesis would predict that there would be various physical/environmental signs of the Earth warming. Finding those indicators would not necessitate that the hypothesis be true. It would only speak to the general prediction.

To apply it to AGW, it is not that I reject AGW as a possible valid hypothesis for the observed data (I have stated otherwise many times), it is that I don't believe it necessitates that AGW is necessarily a comprehensive hypothesis (in and of itself) for the observed phenomena; meaning that I don't see AGW as a logically sufficient hypothesis for the observable data.

In other words, since I don't reject AGW outright, and I don't know why anyone should (including many on this board), I do question to what extent AGW is involved verse "natural" causes. That is what seems very unclear to me. It seems that AGW + other causes would be a reasonable alternative as well as AGW (minimally) + natural causes.

To you PKT, and the skeptics in general, what evidence would convince you?

I can't speak for others on this board or in life. I tend to think I have a much more narrow skepticism of AGW then they do as I have no doubt that AGW via CO2, methane, etc. certainly is a part of the problem. The real questions being to what extent and how accurate the predictions.

I will say, I do not know what evidence would convince me as I do not know how climate scientists could isolate CO2, methane, or other human affects on the environment as an independent variable. They would have to be able to vastly increase their understanding of all natural causes for the historical cycles of global warming and cooling and then juxtapose them to our current situation to rule them out; leaving only AGW or overwhelmingly AGW. I just don't think that is possible.

 

[Sandvol]

LMAO. Let me guess, Fred Singer is today’s Albert Einstein? So we should ignore every scientific consensus because it’s probably wrong? Revert to the Stone Age? I already posted this, but the fact that the earth is round was discovered millennia ago. Eratosthenes even measured the Earth’s circumference to an impressive degree of accuracy in the 3rd century BC. It was a scientific consensus long before Columbus. The general public is always slower to accept paradigm-shifting discoveries. I’m sure there were plenty of blacksmiths, farmers, bakers, and other professionals back in the day that thought, “It looks pretty darn flat to me!”

This is one of the sillier bones to pick.

The Catholic Church wasn't around in Eratosthenes day. Fred Singer is not proposing an alternate theory. He is just saying it is a hoax because there is no proof. But in Columbus' day scientists supported the Church's view that the Earth was flat for fear of retribution like many scientists today support AGW for fear of retribution or for fear of no funding.

 

[BartW]

Again, we are talking about the same system, same natural laws. Chaos Theory would apply uniformly.

As for the pool example, if one has all relevant information of the system, it would not be that hard providing the fluid dynamics (natural laws of the system in question) are correct and the information/data entered into the system/simulation is correct. However, as your analogy correctly points out, that is a big "if" and is why climate/meteorology models are unreliable.

No, it would still be impossible to determine H(x,y,t) for large t because it’s a chaotic system. If the initial conditions are the tiniest fraction of a millimeter off somewhere the whole system will evolve differently.

Here’s another example of chaotic behavior: predator-prey population curves.

While it’s impossible to determine either population at some point in the future with a high degree of accuracy, we can still predict how the curves will trend based on the system’s parameters (e.g. population capacity). Notice how those curves aren’t regular, like we see for global average temperature.

If anything you could argue that solar irradiance is slightly chaotic because orbital dynamics/the n-body problem is chaotic, but I wouldn’t count on the Milankovitch cycles changing anytime soon. We have begun and will continue to diverge from this regular behavior due to AGW though.

1) If H (Hypothesis) is true, then P (Prediction) is also true
2) Test and Observations say P is true
__________________________________________

Conclusion: H is true.

This is invalid reasoning. It is known formally as "affirming the consequent". In other words, H is not logically only sufficient for P to be true. It could be that some other factors or hypothesis (X) account for why P is true.

We could easily turn this around with the ridiculous hypothesis that "God was angry and wanted humans to feel the discomfort of hell on Earth due to their sin, hence he wanted to warm the Earth." Such a hypothesis would predict that there would be various physical/environmental signs of the Earth warming. Finding those indicators would not necessitate that the hypothesis be true. It would only speak to the general prediction.

To apply it to AGW, it is not that I reject AGW as a possible valid hypothesis for the observed data (I have stated otherwise many times), it is that I don't believe it necessitates that AGW is necessarily a comprehensive hypothesis (in and of itself) for the observed phenomena; meaning that I don't see AGW as a logically sufficient hypothesis for the observable data.

In other words, since I don't reject AGW outright, and I don't know why anyone should (including many on this board), I do question to what extent AGW is involved verse "natural" causes. That is what seems very unclear to me. It seems that AGW + other causes would be a reasonable alternative as well as AGW (minimally) + natural causes.

But the scientific method doesn’t end at support/reject hypothesis (also note that the options are support/reject, not confirm/reject). You go back to the hypothesis step and repeat the cycle over and over. So far all the data supports AGW and none has caused scientists to reject AGW. Science never claims 100% certainty, and denialists (not you – I mean those that actively participate in the smear campaign) are quick to misrepresent this scientific uncertainty as real doubt. At this point, there is no real doubt among scientists.

I can't speak for others on this board or in life. I tend to think I have a much more narrow skepticism of AGW then they do as I have no doubt that AGW via CO2, methane, etc. certainly is a part of the problem. The real questions being to what extent and how accurate the predictions.

I will say, I do not know what evidence would convince me as I do not know how climate scientists could isolate CO2, methane, or other human affects on the environment as an independent variable. They would have to be able to vastly increase their understanding of all natural causes for the historical cycles of global warming and cooling and then juxtapose them to our current situation to rule them out; leaving only AGW or overwhelmingly AGW. I just don't think that is possible.

There actually has been a lot of work done in isolating the component of warming due to increased greenhouse gases. You’d be surprised just how much we know about climate forcings. Models based on these forcings are backcasted to test if they replicate historical cycles of warming, such as in the Vostok ice core plot above. If you are interested in the topic and would like to know more here are some good places to start: link1 link2. I wouldn't discount AGW based on your perception that we don't have a good grasp on the variables when you aren't actually aware of what we do and don't know. No offense. This is in part a problem on the scientists' side of communicating science to the public.

If you don't know what would convince you, let me ask a follow up question. How long do we wait before we admit that we have a problem that requires action?

 

[BartW]

The Catholic Church wasn't around in Eratosthenes day. Fred Singer is not proposing an alternate theory. He is just saying it is a hoax because there is no proof. But in Columbus' day scientists supported the Church's view that the Earth was flat for fear of retribution like many scientists today support AGW for fear of retribution or for fear of no funding.

"The Flat Earth model is an archaic belief that the Earth's shape is a plane or disk. Many ancient cultures have had conceptions of a flat Earth, including Greece until the classical period, the Bronze Age and Iron Age civilizations of the Near East until the Hellenistic period, India until the Gupta period (early centuries AD) and China until the 17th century. It was also typically held in the aboriginal cultures of the Americas, and a flat Earth domed by the firmament in the shape of an inverted bowl is common in pre-scientific societies.[1]

The paradigm of a spherical Earth was developed in Greek astronomy, beginning with Pythagoras (6th century BC), although most Pre-Socratics retained the flat Earth model. Aristotle accepted the spherical shape of the Earth on empirical grounds around 330 BC, and knowledge of the spherical Earth gradually began to spread beyond the Hellenistic world from then on.[2][3][4][5]

The modern misconception that educated Europeans at the time of Columbus believed in a flat Earth, and that his voyages refuted that belief, has been referred to as the Myth of the Flat Earth.[6]"

-Intro to Flat Earth wiki

Ironically it appears the Myth of the Flat Earth gained popularity in the 19th century due to religious opposition to Darwin's Theory of Evolution. Creationists were (and still are) using the same flawed argument as you in an attempt to discredit science.

The wiki for Myth of the Flat Earth and Conflict Thesis are pretty interesting too.

 

[Sandvol]

"The Flat Earth model is an archaic belief that the Earth's shape is a plane or disk. Many ancient cultures have had conceptions of a flat Earth, including Greece until the classical period, the Bronze Age and Iron Age civilizations of the Near East until the Hellenistic period, India until the Gupta period (early centuries AD) and China until the 17th century. It was also typically held in the aboriginal cultures of the Americas, and a flat Earth domed by the firmament in the shape of an inverted bowl is common in pre-scientific societies.[1]

The paradigm of a spherical Earth was developed in Greek astronomy, beginning with Pythagoras (6th century BC), although most Pre-Socratics retained the flat Earth model. Aristotle accepted the spherical shape of the Earth on empirical grounds around 330 BC, and knowledge of the spherical Earth gradually began to spread beyond the Hellenistic world from then on.[2][3][4][5]

The modern misconception that educated Europeans at the time of Columbus believed in a flat Earth, and that his voyages refuted that belief, has been referred to as the Myth of the Flat Earth.[6]"

-Intro to Flat Earth wiki

Ironically it appears the Myth of the Flat Earth gained popularity in the 19th century due to religious opposition to Darwin's Theory of Evolution. Creationists were (and still are) using the same flawed argument as you in an attempt to discredit science.

The wiki for Myth of the Flat Earth and Conflict Thesis are pretty interesting too.

Why don't you stop quoting Wiki and read some books about Columbus? Scientists like Copernicus battled the Church to advance science at their own peril. Many scholars acquiesced whether they really believed it or not. The Church was the consensus. I understand Columbus wasn't the only one who believed in a spherical Earth. That is not my point. You keep going off on tangents. I'm arguing from the point that Scientific Fact is not born out of consensus. It is born out of truth. No amount of consensus can make something true if it isn't true.

 

[Sandvol]

No, it would still be impossible to determine H(x,y,t) for large t because it’s a chaotic system. If the initial conditions are the tiniest fraction of a millimeter off somewhere the whole system will evolve differently.

Here’s another example of chaotic behavior: predator-prey population curves.

While it’s impossible to determine either population at some point in the future with a high degree of accuracy, we can still predict how the curves will trend based on the system’s parameters (e.g. population capacity). Notice how those curves aren’t regular, like we see for global average temperature.

If anything you could argue that solar irradiance is slightly chaotic because orbital dynamics/the n-body problem is chaotic, but I wouldn’t count on the Milankovitch cycles changing anytime soon. We have begun and will continue to diverge from this regular behavior due to AGW though.



But the scientific method doesn’t end at support/reject hypothesis (also note that the options are support/reject, not confirm/reject). You go back to the hypothesis step and repeat the cycle over and over. So far all the data supports AGW and none has caused scientists to reject AGW. Science never claims 100% certainty, and denialists (not you – I mean those that actively participate in the smear campaign) are quick to misrepresent this scientific uncertainty as real doubt. At this point, there is no real doubt among scientists.



There actually has been a lot of work done in isolating the component of warming due to increased greenhouse gases. You’d be surprised just how much we know about climate forcings. Models based on these forcings are backcasted to test if they replicate historical cycles of warming, such as in the Vostok ice core plot above. If you are interested in the topic and would like to know more here are some good places to start: link1 link2. I wouldn't discount AGW based on your perception that we don't have a good grasp on the variables when you aren't actually aware of what we do and don't know. No offense. This is in part a problem on the scientists' side of communicating science to the public.

If you don't know what would convince you, let me ask a follow up question. How long do we wait before we admit that we have a problem that requires action?

If those forcing models were accurate you might have a point. I don't understand why you continually display an inaccurate model as if it had any validity.

 

[Velo Vol]

Global Analysis - January 2014 | State of the Climate | National Climatic Data Center (NCDC)

 

[zreeves]

Arctic Ice Cover Decrease 1978-2010 Time Lapse - YouTube

 

[BartW]

Why don't you stop quoting Wiki and read some books about Columbus? Scientists like Copernicus battled the Church to advance science at their own peril. Many scholars acquiesced whether they really believed it or not. The Church was the consensus. I understand Columbus wasn't the only one who believed in a spherical Earth. That is not my point. You keep going off on tangents. I'm arguing from the point that Scientific Fact is not born out of consensus. It is born out of truth. No amount of consensus can make something true if it isn't true.

You keep accusing me of going off on tangents when I’m directly responding to the content of your posts. You brought up Columbus. I could look up the Myth of the Flat Earth in books and I would know exactly where to go because wiki has citations. Keep believing the myth if you like. Your argument that AGW is a hoax because “the scientific consensus is usually wrong” is absurd.

If those forcing models were accurate you might have a point. I don't understand why you continually display an inaccurate model as if it had any validity.

I don’t understand why you continually speak out of your arse. Here are Hansen’s 1988 predictions:

Hansen even said the most likely scenario would be scenario B (linear increase in GHG). If you factor in that CO2 emissions have actually been slightly lower than the scenario B projection, the modelled temperature trend would be even closer to the observations. Heck, Hansen even predicted a major volcanic eruption (Pinatubo) in his model to within a couple of years (impressive eh?). Here are some more:

How reliable are climate models?

 

[Sandvol]

You keep accusing me of going off on tangents when I’m directly responding to the content of your posts. You brought up Columbus. I could look up the Myth of the Flat Earth in books and I would know exactly where to go because wiki has citations. Keep believing the myth if you like. Your argument that AGW is a hoax because “the scientific consensus is usually wrong” is absurd.



I don’t understand why you continually speak out of your arse. Here are Hansen’s 1988 predictions:

Hansen even said the most likely scenario would be scenario B (linear increase in GHG). If you factor in that CO2 emissions have actually been slightly lower than the scenario B projection, the modelled temperature trend would be even closer to the observations. Heck, Hansen even predicted a major volcanic eruption (Pinatubo) in his model to within a couple of years (impressive eh?). Here are some more:

How reliable are climate models?

Very good at massaging to fit old data but when it comes to predicting not very good. The models never get out of the testing stage until they have been sufficiently reworked to match historical data.

 

[BartW]

Very good at massaging to fit old data but when it comes to predicting not very good. The models never get out of the testing stage until they have been sufficiently reworked to match historical data.

Hansen made his prediction in 1988. The sea level rise and arctic ice decline plots were model predictions as well. The Pinatubo plot is just to show Hansen's model's consistency. Models should be (and are) backcasted to check for consistency with historical data.

Sandvol, what evidence would convince you?

 

[hog88]

Arctic Ice Cover Decrease 1978-2010 Time Lapse - YouTube

Didn't watch your video but less ice up there would be a good thing for a newly minted geologist. More area for energy exploration = more employment opportunities your you.